Re: Linux 5.4.217

From: Greg Kroah-Hartman
Date: Fri Oct 07 2022 - 03:27:33 EST


diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index db9d53b879f8..8f71a17ad544 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -4298,6 +4298,18 @@

retain_initrd [RAM] Keep initrd memory after extraction

+ retbleed= [X86] Control mitigation of RETBleed (Arbitrary
+ Speculative Code Execution with Return Instructions)
+ vulnerability.
+
+ off - unconditionally disable
+ auto - automatically select a migitation
+
+ Selecting 'auto' will choose a mitigation method at run
+ time according to the CPU.
+
+ Not specifying this option is equivalent to retbleed=auto.
+
rfkill.default_state=
0 "airplane mode". All wifi, bluetooth, wimax, gps, fm,
etc. communication is blocked by default.
@@ -4541,6 +4553,7 @@
eibrs - enhanced IBRS
eibrs,retpoline - enhanced IBRS + Retpolines
eibrs,lfence - enhanced IBRS + LFENCE
+ ibrs - use IBRS to protect kernel

Not specifying this option is equivalent to
spectre_v2=auto.
diff --git a/Documentation/process/code-of-conduct-interpretation.rst b/Documentation/process/code-of-conduct-interpretation.rst
index e899f14a4ba2..4f8a06b00f60 100644
--- a/Documentation/process/code-of-conduct-interpretation.rst
+++ b/Documentation/process/code-of-conduct-interpretation.rst
@@ -51,7 +51,7 @@ the Technical Advisory Board (TAB) or other maintainers if you're
uncertain how to handle situations that come up. It will not be
considered a violation report unless you want it to be. If you are
uncertain about approaching the TAB or any other maintainers, please
-reach out to our conflict mediator, Mishi Choudhary <mishi@xxxxxxxxx>.
+reach out to our conflict mediator, Joanna Lee <joanna.lee@xxxxxxxxxx>.

In the end, "be kind to each other" is really what the end goal is for
everybody. We know everyone is human and we all fail at times, but the
diff --git a/Makefile b/Makefile
index 3d9d7ef6f8bf..201ac8e410a9 100644
--- a/Makefile
+++ b/Makefile
@@ -1,7 +1,7 @@
# SPDX-License-Identifier: GPL-2.0
VERSION = 5
PATCHLEVEL = 4
-SUBLEVEL = 216
+SUBLEVEL = 217
EXTRAVERSION =
NAME = Kleptomaniac Octopus

diff --git a/arch/x86/entry/calling.h b/arch/x86/entry/calling.h
index b3f121478738..29e5675c6d4f 100644
--- a/arch/x86/entry/calling.h
+++ b/arch/x86/entry/calling.h
@@ -6,6 +6,8 @@
#include <asm/percpu.h>
#include <asm/asm-offsets.h>
#include <asm/processor-flags.h>
+#include <asm/msr.h>
+#include <asm/nospec-branch.h>

/*

@@ -146,27 +148,19 @@ For 32-bit we have the following conventions - kernel is built with

.endm

-.macro POP_REGS pop_rdi=1 skip_r11rcx=0
+.macro POP_REGS pop_rdi=1
popq %r15
popq %r14
popq %r13
popq %r12
popq %rbp
popq %rbx
- .if \skip_r11rcx
- popq %rsi
- .else
popq %r11
- .endif
popq %r10
popq %r9
popq %r8
popq %rax
- .if \skip_r11rcx
- popq %rsi
- .else
popq %rcx
- .endif
popq %rdx
popq %rsi
.if \pop_rdi
@@ -316,6 +310,62 @@ For 32-bit we have the following conventions - kernel is built with

#endif

+/*
+ * IBRS kernel mitigation for Spectre_v2.
+ *
+ * Assumes full context is established (PUSH_REGS, CR3 and GS) and it clobbers
+ * the regs it uses (AX, CX, DX). Must be called before the first RET
+ * instruction (NOTE! UNTRAIN_RET includes a RET instruction)
+ *
+ * The optional argument is used to save/restore the current value,
+ * which is used on the paranoid paths.
+ *
+ * Assumes x86_spec_ctrl_{base,current} to have SPEC_CTRL_IBRS set.
+ */
+.macro IBRS_ENTER save_reg
+ ALTERNATIVE "jmp .Lend_\@", "", X86_FEATURE_KERNEL_IBRS
+ movl $MSR_IA32_SPEC_CTRL, %ecx
+
+.ifnb \save_reg
+ rdmsr
+ shl $32, %rdx
+ or %rdx, %rax
+ mov %rax, \save_reg
+ test $SPEC_CTRL_IBRS, %eax
+ jz .Ldo_wrmsr_\@
+ lfence
+ jmp .Lend_\@
+.Ldo_wrmsr_\@:
+.endif
+
+ movq PER_CPU_VAR(x86_spec_ctrl_current), %rdx
+ movl %edx, %eax
+ shr $32, %rdx
+ wrmsr
+.Lend_\@:
+.endm
+
+/*
+ * Similar to IBRS_ENTER, requires KERNEL GS,CR3 and clobbers (AX, CX, DX)
+ * regs. Must be called after the last RET.
+ */
+.macro IBRS_EXIT save_reg
+ ALTERNATIVE "jmp .Lend_\@", "", X86_FEATURE_KERNEL_IBRS
+ movl $MSR_IA32_SPEC_CTRL, %ecx
+
+.ifnb \save_reg
+ mov \save_reg, %rdx
+.else
+ movq PER_CPU_VAR(x86_spec_ctrl_current), %rdx
+ andl $(~SPEC_CTRL_IBRS), %edx
+.endif
+
+ movl %edx, %eax
+ shr $32, %rdx
+ wrmsr
+.Lend_\@:
+.endm
+
/*
* Mitigate Spectre v1 for conditional swapgs code paths.
*
diff --git a/arch/x86/entry/entry_32.S b/arch/x86/entry/entry_32.S
index bde3e0f85425..2d837fb54c31 100644
--- a/arch/x86/entry/entry_32.S
+++ b/arch/x86/entry/entry_32.S
@@ -750,7 +750,6 @@ ENTRY(__switch_to_asm)
movl %ebx, PER_CPU_VAR(stack_canary)+stack_canary_offset
#endif

-#ifdef CONFIG_RETPOLINE
/*
* When switching from a shallower to a deeper call stack
* the RSB may either underflow or use entries populated
@@ -759,7 +758,6 @@ ENTRY(__switch_to_asm)
* speculative execution to prevent attack.
*/
FILL_RETURN_BUFFER %ebx, RSB_CLEAR_LOOPS, X86_FEATURE_RSB_CTXSW
-#endif

/* restore callee-saved registers */
popfl
diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S
index 2ba3d53ac5b1..c82136030d58 100644
--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -172,6 +172,10 @@ GLOBAL(entry_SYSCALL_64_after_hwframe)
/* IRQs are off. */
movq %rax, %rdi
movq %rsp, %rsi
+
+ /* clobbers %rax, make sure it is after saving the syscall nr */
+ IBRS_ENTER
+
call do_syscall_64 /* returns with IRQs disabled */

TRACE_IRQS_IRETQ /* we're about to change IF */
@@ -248,8 +252,8 @@ GLOBAL(entry_SYSCALL_64_after_hwframe)
* perf profiles. Nothing jumps here.
*/
syscall_return_via_sysret:
- /* rcx and r11 are already restored (see code above) */
- POP_REGS pop_rdi=0 skip_r11rcx=1
+ IBRS_EXIT
+ POP_REGS pop_rdi=0

/*
* Now all regs are restored except RSP and RDI.
@@ -301,7 +305,6 @@ ENTRY(__switch_to_asm)
movq %rbx, PER_CPU_VAR(fixed_percpu_data) + stack_canary_offset
#endif

-#ifdef CONFIG_RETPOLINE
/*
* When switching from a shallower to a deeper call stack
* the RSB may either underflow or use entries populated
@@ -310,7 +313,6 @@ ENTRY(__switch_to_asm)
* speculative execution to prevent attack.
*/
FILL_RETURN_BUFFER %r12, RSB_CLEAR_LOOPS, X86_FEATURE_RSB_CTXSW
-#endif

/* restore callee-saved registers */
popq %r15
@@ -622,6 +624,7 @@ GLOBAL(retint_user)
TRACE_IRQS_IRETQ

GLOBAL(swapgs_restore_regs_and_return_to_usermode)
+ IBRS_EXIT
#ifdef CONFIG_DEBUG_ENTRY
/* Assert that pt_regs indicates user mode. */
testb $3, CS(%rsp)
@@ -1248,7 +1251,13 @@ ENTRY(paranoid_entry)
*/
FENCE_SWAPGS_KERNEL_ENTRY

- ret
+ /*
+ * Once we have CR3 and %GS setup save and set SPEC_CTRL. Just like
+ * CR3 above, keep the old value in a callee saved register.
+ */
+ IBRS_ENTER save_reg=%r15
+
+ RET
END(paranoid_entry)

/*
@@ -1276,12 +1285,20 @@ ENTRY(paranoid_exit)
jmp .Lparanoid_exit_restore
.Lparanoid_exit_no_swapgs:
TRACE_IRQS_IRETQ_DEBUG
+
+ /*
+ * Must restore IBRS state before both CR3 and %GS since we need access
+ * to the per-CPU x86_spec_ctrl_shadow variable.
+ */
+ IBRS_EXIT save_reg=%r15
+
/* Always restore stashed CR3 value (see paranoid_entry) */
RESTORE_CR3 scratch_reg=%rbx save_reg=%r14
.Lparanoid_exit_restore:
jmp restore_regs_and_return_to_kernel
END(paranoid_exit)

+
/*
* Save all registers in pt_regs, and switch GS if needed.
*/
@@ -1301,6 +1318,7 @@ ENTRY(error_entry)
FENCE_SWAPGS_USER_ENTRY
/* We have user CR3. Change to kernel CR3. */
SWITCH_TO_KERNEL_CR3 scratch_reg=%rax
+ IBRS_ENTER

.Lerror_entry_from_usermode_after_swapgs:
/* Put us onto the real thread stack. */
@@ -1356,6 +1374,7 @@ ENTRY(error_entry)
SWAPGS
FENCE_SWAPGS_USER_ENTRY
SWITCH_TO_KERNEL_CR3 scratch_reg=%rax
+ IBRS_ENTER

/*
* Pretend that the exception came from user mode: set up pt_regs
@@ -1461,6 +1480,8 @@ ENTRY(nmi)
PUSH_AND_CLEAR_REGS rdx=(%rdx)
ENCODE_FRAME_POINTER

+ IBRS_ENTER
+
/*
* At this point we no longer need to worry about stack damage
* due to nesting -- we're on the normal thread stack and we're
@@ -1684,6 +1705,9 @@ end_repeat_nmi:
movq $-1, %rsi
call do_nmi

+ /* Always restore stashed SPEC_CTRL value (see paranoid_entry) */
+ IBRS_EXIT save_reg=%r15
+
/* Always restore stashed CR3 value (see paranoid_entry) */
RESTORE_CR3 scratch_reg=%r15 save_reg=%r14

diff --git a/arch/x86/entry/entry_64_compat.S b/arch/x86/entry/entry_64_compat.S
index 39913770a44d..c3c4ea4a6711 100644
--- a/arch/x86/entry/entry_64_compat.S
+++ b/arch/x86/entry/entry_64_compat.S
@@ -4,7 +4,6 @@
*
* Copyright 2000-2002 Andi Kleen, SuSE Labs.
*/
-#include "calling.h"
#include <asm/asm-offsets.h>
#include <asm/current.h>
#include <asm/errno.h>
@@ -17,6 +16,8 @@
#include <linux/linkage.h>
#include <linux/err.h>

+#include "calling.h"
+
.section .entry.text, "ax"

/*
@@ -106,6 +107,8 @@ ENTRY(entry_SYSENTER_compat)
xorl %r15d, %r15d /* nospec r15 */
cld

+ IBRS_ENTER
+
/*
* SYSENTER doesn't filter flags, so we need to clear NT and AC
* ourselves. To save a few cycles, we can check whether
@@ -253,6 +256,8 @@ GLOBAL(entry_SYSCALL_compat_after_hwframe)
*/
TRACE_IRQS_OFF

+ IBRS_ENTER
+
movq %rsp, %rdi
call do_fast_syscall_32
/* XEN PV guests always use IRET path */
@@ -267,6 +272,9 @@ sysret32_from_system_call:
*/
STACKLEAK_ERASE
TRACE_IRQS_ON /* User mode traces as IRQs on. */
+
+ IBRS_EXIT
+
movq RBX(%rsp), %rbx /* pt_regs->rbx */
movq RBP(%rsp), %rbp /* pt_regs->rbp */
movq EFLAGS(%rsp), %r11 /* pt_regs->flags (in r11) */
@@ -408,6 +416,7 @@ ENTRY(entry_INT80_compat)
* gate turned them off.
*/
TRACE_IRQS_OFF
+ IBRS_ENTER

movq %rsp, %rdi
call do_int80_syscall_32
diff --git a/arch/x86/include/asm/cpu_device_id.h b/arch/x86/include/asm/cpu_device_id.h
index 0c814cd9ea42..cdf39decf734 100644
--- a/arch/x86/include/asm/cpu_device_id.h
+++ b/arch/x86/include/asm/cpu_device_id.h
@@ -5,15 +5,22 @@
/*
* Declare drivers belonging to specific x86 CPUs
* Similar in spirit to pci_device_id and related PCI functions
+ *
+ * The wildcard initializers are in mod_devicetable.h because
+ * file2alias needs them. Sigh.
*/
-
#include <linux/mod_devicetable.h>
+/* Get the INTEL_FAM* model defines */
+#include <asm/intel-family.h>
+/* And the X86_VENDOR_* ones */
+#include <asm/processor.h>

+/* Centaur FAM6 models */
+#define X86_CENTAUR_FAM6_C7_A 0xa
#define X86_CENTAUR_FAM6_C7_D 0xd
#define X86_CENTAUR_FAM6_NANO 0xf

#define X86_STEPPINGS(mins, maxs) GENMASK(maxs, mins)
-
/**
* X86_MATCH_VENDOR_FAM_MODEL_STEPPINGS_FEATURE - Base macro for CPU matching
* @_vendor: The vendor name, e.g. INTEL, AMD, HYGON, ..., ANY
@@ -26,8 +33,11 @@
* format is unsigned long. The supplied value, pointer
* etc. is casted to unsigned long internally.
*
- * Backport version to keep the SRBDS pile consistant. No shorter variants
- * required for this.
+ * Use only if you need all selectors. Otherwise use one of the shorter
+ * macros of the X86_MATCH_* family. If there is no matching shorthand
+ * macro, consider to add one. If you really need to wrap one of the macros
+ * into another macro at the usage site for good reasons, then please
+ * start this local macro with X86_MATCH to allow easy grepping.
*/
#define X86_MATCH_VENDOR_FAM_MODEL_STEPPINGS_FEATURE(_vendor, _family, _model, \
_steppings, _feature, _data) { \
@@ -39,6 +49,120 @@
.driver_data = (unsigned long) _data \
}

+/**
+ * X86_MATCH_VENDOR_FAM_MODEL_FEATURE - Macro for CPU matching
+ * @_vendor: The vendor name, e.g. INTEL, AMD, HYGON, ..., ANY
+ * The name is expanded to X86_VENDOR_@_vendor
+ * @_family: The family number or X86_FAMILY_ANY
+ * @_model: The model number, model constant or X86_MODEL_ANY
+ * @_feature: A X86_FEATURE bit or X86_FEATURE_ANY
+ * @_data: Driver specific data or NULL. The internal storage
+ * format is unsigned long. The supplied value, pointer
+ * etc. is casted to unsigned long internally.
+ *
+ * The steppings arguments of X86_MATCH_VENDOR_FAM_MODEL_STEPPINGS_FEATURE() is
+ * set to wildcards.
+ */
+#define X86_MATCH_VENDOR_FAM_MODEL_FEATURE(vendor, family, model, feature, data) \
+ X86_MATCH_VENDOR_FAM_MODEL_STEPPINGS_FEATURE(vendor, family, model, \
+ X86_STEPPING_ANY, feature, data)
+
+/**
+ * X86_MATCH_VENDOR_FAM_FEATURE - Macro for matching vendor, family and CPU feature
+ * @vendor: The vendor name, e.g. INTEL, AMD, HYGON, ..., ANY
+ * The name is expanded to X86_VENDOR_@vendor
+ * @family: The family number or X86_FAMILY_ANY
+ * @feature: A X86_FEATURE bit
+ * @data: Driver specific data or NULL. The internal storage
+ * format is unsigned long. The supplied value, pointer
+ * etc. is casted to unsigned long internally.
+ *
+ * All other missing arguments of X86_MATCH_VENDOR_FAM_MODEL_FEATURE() are
+ * set to wildcards.
+ */
+#define X86_MATCH_VENDOR_FAM_FEATURE(vendor, family, feature, data) \
+ X86_MATCH_VENDOR_FAM_MODEL_FEATURE(vendor, family, \
+ X86_MODEL_ANY, feature, data)
+
+/**
+ * X86_MATCH_VENDOR_FEATURE - Macro for matching vendor and CPU feature
+ * @vendor: The vendor name, e.g. INTEL, AMD, HYGON, ..., ANY
+ * The name is expanded to X86_VENDOR_@vendor
+ * @feature: A X86_FEATURE bit
+ * @data: Driver specific data or NULL. The internal storage
+ * format is unsigned long. The supplied value, pointer
+ * etc. is casted to unsigned long internally.
+ *
+ * All other missing arguments of X86_MATCH_VENDOR_FAM_MODEL_FEATURE() are
+ * set to wildcards.
+ */
+#define X86_MATCH_VENDOR_FEATURE(vendor, feature, data) \
+ X86_MATCH_VENDOR_FAM_FEATURE(vendor, X86_FAMILY_ANY, feature, data)
+
+/**
+ * X86_MATCH_FEATURE - Macro for matching a CPU feature
+ * @feature: A X86_FEATURE bit
+ * @data: Driver specific data or NULL. The internal storage
+ * format is unsigned long. The supplied value, pointer
+ * etc. is casted to unsigned long internally.
+ *
+ * All other missing arguments of X86_MATCH_VENDOR_FAM_MODEL_FEATURE() are
+ * set to wildcards.
+ */
+#define X86_MATCH_FEATURE(feature, data) \
+ X86_MATCH_VENDOR_FEATURE(ANY, feature, data)
+
+/* Transitional to keep the existing code working */
+#define X86_FEATURE_MATCH(feature) X86_MATCH_FEATURE(feature, NULL)
+
+/**
+ * X86_MATCH_VENDOR_FAM_MODEL - Match vendor, family and model
+ * @vendor: The vendor name, e.g. INTEL, AMD, HYGON, ..., ANY
+ * The name is expanded to X86_VENDOR_@vendor
+ * @family: The family number or X86_FAMILY_ANY
+ * @model: The model number, model constant or X86_MODEL_ANY
+ * @data: Driver specific data or NULL. The internal storage
+ * format is unsigned long. The supplied value, pointer
+ * etc. is casted to unsigned long internally.
+ *
+ * All other missing arguments of X86_MATCH_VENDOR_FAM_MODEL_FEATURE() are
+ * set to wildcards.
+ */
+#define X86_MATCH_VENDOR_FAM_MODEL(vendor, family, model, data) \
+ X86_MATCH_VENDOR_FAM_MODEL_FEATURE(vendor, family, model, \
+ X86_FEATURE_ANY, data)
+
+/**
+ * X86_MATCH_VENDOR_FAM - Match vendor and family
+ * @vendor: The vendor name, e.g. INTEL, AMD, HYGON, ..., ANY
+ * The name is expanded to X86_VENDOR_@vendor
+ * @family: The family number or X86_FAMILY_ANY
+ * @data: Driver specific data or NULL. The internal storage
+ * format is unsigned long. The supplied value, pointer
+ * etc. is casted to unsigned long internally.
+ *
+ * All other missing arguments to X86_MATCH_VENDOR_FAM_MODEL_FEATURE() are
+ * set of wildcards.
+ */
+#define X86_MATCH_VENDOR_FAM(vendor, family, data) \
+ X86_MATCH_VENDOR_FAM_MODEL(vendor, family, X86_MODEL_ANY, data)
+
+/**
+ * X86_MATCH_INTEL_FAM6_MODEL - Match vendor INTEL, family 6 and model
+ * @model: The model name without the INTEL_FAM6_ prefix or ANY
+ * The model name is expanded to INTEL_FAM6_@model internally
+ * @data: Driver specific data or NULL. The internal storage
+ * format is unsigned long. The supplied value, pointer
+ * etc. is casted to unsigned long internally.
+ *
+ * The vendor is set to INTEL, the family to 6 and all other missing
+ * arguments of X86_MATCH_VENDOR_FAM_MODEL_FEATURE() are set to wildcards.
+ *
+ * See X86_MATCH_VENDOR_FAM_MODEL_FEATURE() for further information.
+ */
+#define X86_MATCH_INTEL_FAM6_MODEL(model, data) \
+ X86_MATCH_VENDOR_FAM_MODEL(INTEL, 6, INTEL_FAM6_##model, data)
+
/*
* Match specific microcode revisions.
*
diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h
index 736b0e412344..2ec85d7bfdff 100644
--- a/arch/x86/include/asm/cpufeatures.h
+++ b/arch/x86/include/asm/cpufeatures.h
@@ -203,8 +203,8 @@
#define X86_FEATURE_PROC_FEEDBACK ( 7*32+ 9) /* AMD ProcFeedbackInterface */
#define X86_FEATURE_SME ( 7*32+10) /* AMD Secure Memory Encryption */
#define X86_FEATURE_PTI ( 7*32+11) /* Kernel Page Table Isolation enabled */
-#define X86_FEATURE_RETPOLINE ( 7*32+12) /* "" Generic Retpoline mitigation for Spectre variant 2 */
-#define X86_FEATURE_RETPOLINE_LFENCE ( 7*32+13) /* "" Use LFENCE for Spectre variant 2 */
+#define X86_FEATURE_KERNEL_IBRS ( 7*32+12) /* "" Set/clear IBRS on kernel entry/exit */
+#define X86_FEATURE_RSB_VMEXIT ( 7*32+13) /* "" Fill RSB on VM-Exit */
#define X86_FEATURE_INTEL_PPIN ( 7*32+14) /* Intel Processor Inventory Number */
#define X86_FEATURE_CDP_L2 ( 7*32+15) /* Code and Data Prioritization L2 */
#define X86_FEATURE_MSR_SPEC_CTRL ( 7*32+16) /* "" MSR SPEC_CTRL is implemented */
@@ -286,7 +286,10 @@
#define X86_FEATURE_CQM_MBM_LOCAL (11*32+ 3) /* LLC Local MBM monitoring */
#define X86_FEATURE_FENCE_SWAPGS_USER (11*32+ 4) /* "" LFENCE in user entry SWAPGS path */
#define X86_FEATURE_FENCE_SWAPGS_KERNEL (11*32+ 5) /* "" LFENCE in kernel entry SWAPGS path */
-#define X86_FEATURE_RSB_VMEXIT_LITE (11*32+ 6) /* "" Fill RSB on VM exit when EIBRS is enabled */
+#define X86_FEATURE_RRSBA_CTRL (11*32+11) /* "" RET prediction control */
+#define X86_FEATURE_RETPOLINE (11*32+12) /* "" Generic Retpoline mitigation for Spectre variant 2 */
+#define X86_FEATURE_RETPOLINE_LFENCE (11*32+13) /* "" Use LFENCE for Spectre variant 2 */
+#define X86_FEATURE_RSB_VMEXIT_LITE (11*32+17) /* "" Fill RSB on VM exit when EIBRS is enabled */

/* Intel-defined CPU features, CPUID level 0x00000007:1 (EAX), word 12 */
#define X86_FEATURE_AVX512_BF16 (12*32+ 5) /* AVX512 BFLOAT16 instructions */
@@ -303,6 +306,7 @@
#define X86_FEATURE_AMD_SSBD (13*32+24) /* "" Speculative Store Bypass Disable */
#define X86_FEATURE_VIRT_SSBD (13*32+25) /* Virtualized Speculative Store Bypass Disable */
#define X86_FEATURE_AMD_SSB_NO (13*32+26) /* "" Speculative Store Bypass is fixed in hardware. */
+#define X86_FEATURE_BTC_NO (13*32+29) /* "" Not vulnerable to Branch Type Confusion */

/* Thermal and Power Management Leaf, CPUID level 0x00000006 (EAX), word 14 */
#define X86_FEATURE_DTHERM (14*32+ 0) /* Digital Thermal Sensor */
@@ -407,7 +411,8 @@
#define X86_BUG_ITLB_MULTIHIT X86_BUG(23) /* CPU may incur MCE during certain page attribute changes */
#define X86_BUG_SRBDS X86_BUG(24) /* CPU may leak RNG bits if not mitigated */
#define X86_BUG_MMIO_STALE_DATA X86_BUG(25) /* CPU is affected by Processor MMIO Stale Data vulnerabilities */
-#define X86_BUG_MMIO_UNKNOWN X86_BUG(26) /* CPU is too old and its MMIO Stale Data status is unknown */
+#define X86_BUG_RETBLEED X86_BUG(26) /* CPU is affected by RETBleed */
#define X86_BUG_EIBRS_PBRSB X86_BUG(27) /* EIBRS is vulnerable to Post Barrier RSB Predictions */
+#define X86_BUG_MMIO_UNKNOWN X86_BUG(28) /* CPU is too old and its MMIO Stale Data status is unknown */

#endif /* _ASM_X86_CPUFEATURES_H */
diff --git a/arch/x86/include/asm/intel-family.h b/arch/x86/include/asm/intel-family.h
index 5b07573c3bc8..c1d6d8bbb7da 100644
--- a/arch/x86/include/asm/intel-family.h
+++ b/arch/x86/include/asm/intel-family.h
@@ -35,6 +35,9 @@
* The #define line may optionally include a comment including platform names.
*/

+/* Wildcard match for FAM6 so X86_MATCH_INTEL_FAM6_MODEL(ANY) works */
+#define INTEL_FAM6_ANY X86_MODEL_ANY
+
#define INTEL_FAM6_CORE_YONAH 0x0E

#define INTEL_FAM6_CORE2_MEROM 0x0F
@@ -126,6 +129,9 @@
#define INTEL_FAM6_XEON_PHI_KNL 0x57 /* Knights Landing */
#define INTEL_FAM6_XEON_PHI_KNM 0x85 /* Knights Mill */

+/* Family 5 */
+#define INTEL_FAM5_QUARK_X1000 0x09 /* Quark X1000 SoC */
+
/* Useful macros */
#define INTEL_CPU_FAM_ANY(_family, _model, _driver_data) \
{ \
diff --git a/arch/x86/include/asm/msr-index.h b/arch/x86/include/asm/msr-index.h
index cef4eba03ff3..713886d5493a 100644
--- a/arch/x86/include/asm/msr-index.h
+++ b/arch/x86/include/asm/msr-index.h
@@ -47,6 +47,8 @@
#define SPEC_CTRL_STIBP BIT(SPEC_CTRL_STIBP_SHIFT) /* STIBP mask */
#define SPEC_CTRL_SSBD_SHIFT 2 /* Speculative Store Bypass Disable bit */
#define SPEC_CTRL_SSBD BIT(SPEC_CTRL_SSBD_SHIFT) /* Speculative Store Bypass Disable */
+#define SPEC_CTRL_RRSBA_DIS_S_SHIFT 6 /* Disable RRSBA behavior */
+#define SPEC_CTRL_RRSBA_DIS_S BIT(SPEC_CTRL_RRSBA_DIS_S_SHIFT)

#define MSR_IA32_PRED_CMD 0x00000049 /* Prediction Command */
#define PRED_CMD_IBPB BIT(0) /* Indirect Branch Prediction Barrier */
@@ -82,6 +84,7 @@
#define MSR_IA32_ARCH_CAPABILITIES 0x0000010a
#define ARCH_CAP_RDCL_NO BIT(0) /* Not susceptible to Meltdown */
#define ARCH_CAP_IBRS_ALL BIT(1) /* Enhanced IBRS support */
+#define ARCH_CAP_RSBA BIT(2) /* RET may use alternative branch predictors */
#define ARCH_CAP_SKIP_VMENTRY_L1DFLUSH BIT(3) /* Skip L1D flush on vmentry */
#define ARCH_CAP_SSB_NO BIT(4) /*
* Not susceptible to Speculative Store Bypass
@@ -129,6 +132,13 @@
* bit available to control VERW
* behavior.
*/
+#define ARCH_CAP_RRSBA BIT(19) /*
+ * Indicates RET may use predictors
+ * other than the RSB. With eIBRS
+ * enabled predictions in kernel mode
+ * are restricted to targets in
+ * kernel.
+ */
#define ARCH_CAP_PBRSB_NO BIT(24) /*
* Not susceptible to Post-Barrier
* Return Stack Buffer Predictions.
diff --git a/arch/x86/include/asm/nospec-branch.h b/arch/x86/include/asm/nospec-branch.h
index a1ee1a760c3e..8c898eed2894 100644
--- a/arch/x86/include/asm/nospec-branch.h
+++ b/arch/x86/include/asm/nospec-branch.h
@@ -4,11 +4,14 @@
#define _ASM_X86_NOSPEC_BRANCH_H_

#include <linux/static_key.h>
+#include <linux/frame.h>

#include <asm/alternative.h>
#include <asm/alternative-asm.h>
#include <asm/cpufeatures.h>
#include <asm/msr-index.h>
+#include <asm/unwind_hints.h>
+#include <asm/percpu.h>

/*
* This should be used immediately before a retpoline alternative. It tells
@@ -60,9 +63,9 @@
lfence; \
jmp 775b; \
774: \
+ add $(BITS_PER_LONG/8) * 2, sp; \
dec reg; \
jnz 771b; \
- add $(BITS_PER_LONG/8) * nr, sp; \
/* barrier for jnz misprediction */ \
lfence;
#else
@@ -79,13 +82,6 @@
add $(BITS_PER_LONG/8) * nr, sp;
#endif

-#define __ISSUE_UNBALANCED_RET_GUARD(sp) \
- call 881f; \
- int3; \
-881: \
- add $(BITS_PER_LONG/8), sp; \
- lfence;
-
#ifdef __ASSEMBLY__

/*
@@ -155,26 +151,28 @@
#endif
.endm

-.macro ISSUE_UNBALANCED_RET_GUARD ftr:req
- ANNOTATE_NOSPEC_ALTERNATIVE
- ALTERNATIVE "jmp .Lskip_pbrsb_\@", \
- __stringify(__ISSUE_UNBALANCED_RET_GUARD(%_ASM_SP)) \
- \ftr
-.Lskip_pbrsb_\@:
+.macro ISSUE_UNBALANCED_RET_GUARD
+ call .Lunbalanced_ret_guard_\@
+ int3
+.Lunbalanced_ret_guard_\@:
+ add $(BITS_PER_LONG/8), %_ASM_SP
+ lfence
.endm

/*
* A simpler FILL_RETURN_BUFFER macro. Don't make people use the CPP
* monstrosity above, manually.
*/
-.macro FILL_RETURN_BUFFER reg:req nr:req ftr:req
-#ifdef CONFIG_RETPOLINE
- ANNOTATE_NOSPEC_ALTERNATIVE
- ALTERNATIVE "jmp .Lskip_rsb_\@", \
- __stringify(__FILL_RETURN_BUFFER(\reg,\nr,%_ASM_SP)) \
- \ftr
+.macro FILL_RETURN_BUFFER reg:req nr:req ftr:req ftr2
+.ifb \ftr2
+ ALTERNATIVE "jmp .Lskip_rsb_\@", "", \ftr
+.else
+ ALTERNATIVE_2 "jmp .Lskip_rsb_\@", "", \ftr, "jmp .Lunbalanced_\@", \ftr2
+.endif
+ __FILL_RETURN_BUFFER(\reg,\nr,%_ASM_SP)
+.Lunbalanced_\@:
+ ISSUE_UNBALANCED_RET_GUARD
.Lskip_rsb_\@:
-#endif
.endm

#else /* __ASSEMBLY__ */
@@ -249,6 +247,7 @@ enum spectre_v2_mitigation {
SPECTRE_V2_EIBRS,
SPECTRE_V2_EIBRS_RETPOLINE,
SPECTRE_V2_EIBRS_LFENCE,
+ SPECTRE_V2_IBRS,
};

/* The indirect branch speculation control variants */
@@ -312,6 +311,9 @@ static inline void indirect_branch_prediction_barrier(void)

/* The Intel SPEC CTRL MSR base value cache */
extern u64 x86_spec_ctrl_base;
+DECLARE_PER_CPU(u64, x86_spec_ctrl_current);
+extern void write_spec_ctrl_current(u64 val, bool force);
+extern u64 spec_ctrl_current(void);

/*
* With retpoline, we must use IBRS to restrict branch prediction
@@ -321,18 +323,16 @@ extern u64 x86_spec_ctrl_base;
*/
#define firmware_restrict_branch_speculation_start() \
do { \
- u64 val = x86_spec_ctrl_base | SPEC_CTRL_IBRS; \
- \
preempt_disable(); \
- alternative_msr_write(MSR_IA32_SPEC_CTRL, val, \
+ alternative_msr_write(MSR_IA32_SPEC_CTRL, \
+ spec_ctrl_current() | SPEC_CTRL_IBRS, \
X86_FEATURE_USE_IBRS_FW); \
} while (0)

#define firmware_restrict_branch_speculation_end() \
do { \
- u64 val = x86_spec_ctrl_base; \
- \
- alternative_msr_write(MSR_IA32_SPEC_CTRL, val, \
+ alternative_msr_write(MSR_IA32_SPEC_CTRL, \
+ spec_ctrl_current(), \
X86_FEATURE_USE_IBRS_FW); \
preempt_enable(); \
} while (0)
diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index 88cef978380b..5571b28d35b6 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -894,12 +894,21 @@ static void init_amd_zn(struct cpuinfo_x86 *c)
node_reclaim_distance = 32;
#endif

- /*
- * Fix erratum 1076: CPB feature bit not being set in CPUID.
- * Always set it, except when running under a hypervisor.
- */
- if (!cpu_has(c, X86_FEATURE_HYPERVISOR) && !cpu_has(c, X86_FEATURE_CPB))
- set_cpu_cap(c, X86_FEATURE_CPB);
+ /* Fix up CPUID bits, but only if not virtualised. */
+ if (!cpu_has(c, X86_FEATURE_HYPERVISOR)) {
+
+ /* Erratum 1076: CPB feature bit not being set in CPUID. */
+ if (!cpu_has(c, X86_FEATURE_CPB))
+ set_cpu_cap(c, X86_FEATURE_CPB);
+
+ /*
+ * Zen3 (Fam19 model < 0x10) parts are not susceptible to
+ * Branch Type Confusion, but predate the allocation of the
+ * BTC_NO bit.
+ */
+ if (c->x86 == 0x19 && !cpu_has(c, X86_FEATURE_BTC_NO))
+ set_cpu_cap(c, X86_FEATURE_BTC_NO);
+ }
}

static void init_amd(struct cpuinfo_x86 *c)
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index c90d91cb1434..cf5a18e261e3 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -37,6 +37,8 @@

static void __init spectre_v1_select_mitigation(void);
static void __init spectre_v2_select_mitigation(void);
+static void __init retbleed_select_mitigation(void);
+static void __init spectre_v2_user_select_mitigation(void);
static void __init ssb_select_mitigation(void);
static void __init l1tf_select_mitigation(void);
static void __init mds_select_mitigation(void);
@@ -46,16 +48,40 @@ static void __init taa_select_mitigation(void);
static void __init mmio_select_mitigation(void);
static void __init srbds_select_mitigation(void);

-/* The base value of the SPEC_CTRL MSR that always has to be preserved. */
+/* The base value of the SPEC_CTRL MSR without task-specific bits set */
u64 x86_spec_ctrl_base;
EXPORT_SYMBOL_GPL(x86_spec_ctrl_base);
+
+/* The current value of the SPEC_CTRL MSR with task-specific bits set */
+DEFINE_PER_CPU(u64, x86_spec_ctrl_current);
+EXPORT_SYMBOL_GPL(x86_spec_ctrl_current);
+
static DEFINE_MUTEX(spec_ctrl_mutex);

/*
- * The vendor and possibly platform specific bits which can be modified in
- * x86_spec_ctrl_base.
+ * Keep track of the SPEC_CTRL MSR value for the current task, which may differ
+ * from x86_spec_ctrl_base due to STIBP/SSB in __speculation_ctrl_update().
*/
-static u64 __ro_after_init x86_spec_ctrl_mask = SPEC_CTRL_IBRS;
+void write_spec_ctrl_current(u64 val, bool force)
+{
+ if (this_cpu_read(x86_spec_ctrl_current) == val)
+ return;
+
+ this_cpu_write(x86_spec_ctrl_current, val);
+
+ /*
+ * When KERNEL_IBRS this MSR is written on return-to-user, unless
+ * forced the update can be delayed until that time.
+ */
+ if (force || !cpu_feature_enabled(X86_FEATURE_KERNEL_IBRS))
+ wrmsrl(MSR_IA32_SPEC_CTRL, val);
+}
+
+u64 spec_ctrl_current(void)
+{
+ return this_cpu_read(x86_spec_ctrl_current);
+}
+EXPORT_SYMBOL_GPL(spec_ctrl_current);

/*
* AMD specific MSR info for Speculative Store Bypass control.
@@ -105,13 +131,21 @@ void __init check_bugs(void)
if (boot_cpu_has(X86_FEATURE_MSR_SPEC_CTRL))
rdmsrl(MSR_IA32_SPEC_CTRL, x86_spec_ctrl_base);

- /* Allow STIBP in MSR_SPEC_CTRL if supported */
- if (boot_cpu_has(X86_FEATURE_STIBP))
- x86_spec_ctrl_mask |= SPEC_CTRL_STIBP;
-
/* Select the proper CPU mitigations before patching alternatives: */
spectre_v1_select_mitigation();
spectre_v2_select_mitigation();
+ /*
+ * retbleed_select_mitigation() relies on the state set by
+ * spectre_v2_select_mitigation(); specifically it wants to know about
+ * spectre_v2=ibrs.
+ */
+ retbleed_select_mitigation();
+ /*
+ * spectre_v2_user_select_mitigation() relies on the state set by
+ * retbleed_select_mitigation(); specifically the STIBP selection is
+ * forced for UNRET.
+ */
+ spectre_v2_user_select_mitigation();
ssb_select_mitigation();
l1tf_select_mitigation();
md_clear_select_mitigation();
@@ -151,31 +185,17 @@ void __init check_bugs(void)
#endif
}

+/*
+ * NOTE: For VMX, this function is not called in the vmexit path.
+ * It uses vmx_spec_ctrl_restore_host() instead.
+ */
void
x86_virt_spec_ctrl(u64 guest_spec_ctrl, u64 guest_virt_spec_ctrl, bool setguest)
{
- u64 msrval, guestval, hostval = x86_spec_ctrl_base;
+ u64 msrval, guestval = guest_spec_ctrl, hostval = spec_ctrl_current();
struct thread_info *ti = current_thread_info();

- /* Is MSR_SPEC_CTRL implemented ? */
if (static_cpu_has(X86_FEATURE_MSR_SPEC_CTRL)) {
- /*
- * Restrict guest_spec_ctrl to supported values. Clear the
- * modifiable bits in the host base value and or the
- * modifiable bits from the guest value.
- */
- guestval = hostval & ~x86_spec_ctrl_mask;
- guestval |= guest_spec_ctrl & x86_spec_ctrl_mask;
-
- /* SSBD controlled in MSR_SPEC_CTRL */
- if (static_cpu_has(X86_FEATURE_SPEC_CTRL_SSBD) ||
- static_cpu_has(X86_FEATURE_AMD_SSBD))
- hostval |= ssbd_tif_to_spec_ctrl(ti->flags);
-
- /* Conditional STIBP enabled? */
- if (static_branch_unlikely(&switch_to_cond_stibp))
- hostval |= stibp_tif_to_spec_ctrl(ti->flags);
-
if (hostval != guestval) {
msrval = setguest ? guestval : hostval;
wrmsrl(MSR_IA32_SPEC_CTRL, msrval);
@@ -705,12 +725,103 @@ static int __init nospectre_v1_cmdline(char *str)
}
early_param("nospectre_v1", nospectre_v1_cmdline);

-#undef pr_fmt
-#define pr_fmt(fmt) "Spectre V2 : " fmt
-
static enum spectre_v2_mitigation spectre_v2_enabled __ro_after_init =
SPECTRE_V2_NONE;

+#undef pr_fmt
+#define pr_fmt(fmt) "RETBleed: " fmt
+
+enum retbleed_mitigation {
+ RETBLEED_MITIGATION_NONE,
+ RETBLEED_MITIGATION_IBRS,
+ RETBLEED_MITIGATION_EIBRS,
+};
+
+enum retbleed_mitigation_cmd {
+ RETBLEED_CMD_OFF,
+ RETBLEED_CMD_AUTO,
+};
+
+const char * const retbleed_strings[] = {
+ [RETBLEED_MITIGATION_NONE] = "Vulnerable",
+ [RETBLEED_MITIGATION_IBRS] = "Mitigation: IBRS",
+ [RETBLEED_MITIGATION_EIBRS] = "Mitigation: Enhanced IBRS",
+};
+
+static enum retbleed_mitigation retbleed_mitigation __ro_after_init =
+ RETBLEED_MITIGATION_NONE;
+static enum retbleed_mitigation_cmd retbleed_cmd __ro_after_init =
+ RETBLEED_CMD_AUTO;
+
+static int __init retbleed_parse_cmdline(char *str)
+{
+ if (!str)
+ return -EINVAL;
+
+ if (!strcmp(str, "off"))
+ retbleed_cmd = RETBLEED_CMD_OFF;
+ else if (!strcmp(str, "auto"))
+ retbleed_cmd = RETBLEED_CMD_AUTO;
+ else
+ pr_err("Unknown retbleed option (%s). Defaulting to 'auto'\n", str);
+
+ return 0;
+}
+early_param("retbleed", retbleed_parse_cmdline);
+
+#define RETBLEED_UNTRAIN_MSG "WARNING: BTB untrained return thunk mitigation is only effective on AMD/Hygon!\n"
+#define RETBLEED_COMPILER_MSG "WARNING: kernel not compiled with RETPOLINE or -mfunction-return capable compiler!\n"
+#define RETBLEED_INTEL_MSG "WARNING: Spectre v2 mitigation leaves CPU vulnerable to RETBleed attacks, data leaks possible!\n"
+
+static void __init retbleed_select_mitigation(void)
+{
+ if (!boot_cpu_has_bug(X86_BUG_RETBLEED) || cpu_mitigations_off())
+ return;
+
+ switch (retbleed_cmd) {
+ case RETBLEED_CMD_OFF:
+ return;
+
+ case RETBLEED_CMD_AUTO:
+ default:
+ /*
+ * The Intel mitigation (IBRS) was already selected in
+ * spectre_v2_select_mitigation().
+ */
+
+ break;
+ }
+
+ switch (retbleed_mitigation) {
+ default:
+ break;
+ }
+
+ /*
+ * Let IBRS trump all on Intel without affecting the effects of the
+ * retbleed= cmdline option.
+ */
+ if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) {
+ switch (spectre_v2_enabled) {
+ case SPECTRE_V2_IBRS:
+ retbleed_mitigation = RETBLEED_MITIGATION_IBRS;
+ break;
+ case SPECTRE_V2_EIBRS:
+ case SPECTRE_V2_EIBRS_RETPOLINE:
+ case SPECTRE_V2_EIBRS_LFENCE:
+ retbleed_mitigation = RETBLEED_MITIGATION_EIBRS;
+ break;
+ default:
+ pr_err(RETBLEED_INTEL_MSG);
+ }
+ }
+
+ pr_info("%s\n", retbleed_strings[retbleed_mitigation]);
+}
+
+#undef pr_fmt
+#define pr_fmt(fmt) "Spectre V2 : " fmt
+
static enum spectre_v2_user_mitigation spectre_v2_user_stibp __ro_after_init =
SPECTRE_V2_USER_NONE;
static enum spectre_v2_user_mitigation spectre_v2_user_ibpb __ro_after_init =
@@ -740,6 +851,7 @@ static inline const char *spectre_v2_module_string(void) { return ""; }
#define SPECTRE_V2_LFENCE_MSG "WARNING: LFENCE mitigation is not recommended for this CPU, data leaks possible!\n"
#define SPECTRE_V2_EIBRS_EBPF_MSG "WARNING: Unprivileged eBPF is enabled with eIBRS on, data leaks possible via Spectre v2 BHB attacks!\n"
#define SPECTRE_V2_EIBRS_LFENCE_EBPF_SMT_MSG "WARNING: Unprivileged eBPF is enabled with eIBRS+LFENCE mitigation and SMT, data leaks possible via Spectre v2 BHB attacks!\n"
+#define SPECTRE_V2_IBRS_PERF_MSG "WARNING: IBRS mitigation selected on Enhanced IBRS CPU, this may cause unnecessary performance loss\n"

#ifdef CONFIG_BPF_SYSCALL
void unpriv_ebpf_notify(int new_state)
@@ -781,6 +893,7 @@ enum spectre_v2_mitigation_cmd {
SPECTRE_V2_CMD_EIBRS,
SPECTRE_V2_CMD_EIBRS_RETPOLINE,
SPECTRE_V2_CMD_EIBRS_LFENCE,
+ SPECTRE_V2_CMD_IBRS,
};

enum spectre_v2_user_cmd {
@@ -821,13 +934,15 @@ static void __init spec_v2_user_print_cond(const char *reason, bool secure)
pr_info("spectre_v2_user=%s forced on command line.\n", reason);
}

+static __ro_after_init enum spectre_v2_mitigation_cmd spectre_v2_cmd;
+
static enum spectre_v2_user_cmd __init
-spectre_v2_parse_user_cmdline(enum spectre_v2_mitigation_cmd v2_cmd)
+spectre_v2_parse_user_cmdline(void)
{
char arg[20];
int ret, i;

- switch (v2_cmd) {
+ switch (spectre_v2_cmd) {
case SPECTRE_V2_CMD_NONE:
return SPECTRE_V2_USER_CMD_NONE;
case SPECTRE_V2_CMD_FORCE:
@@ -853,15 +968,16 @@ spectre_v2_parse_user_cmdline(enum spectre_v2_mitigation_cmd v2_cmd)
return SPECTRE_V2_USER_CMD_AUTO;
}

-static inline bool spectre_v2_in_eibrs_mode(enum spectre_v2_mitigation mode)
+static inline bool spectre_v2_in_ibrs_mode(enum spectre_v2_mitigation mode)
{
- return (mode == SPECTRE_V2_EIBRS ||
- mode == SPECTRE_V2_EIBRS_RETPOLINE ||
- mode == SPECTRE_V2_EIBRS_LFENCE);
+ return mode == SPECTRE_V2_IBRS ||
+ mode == SPECTRE_V2_EIBRS ||
+ mode == SPECTRE_V2_EIBRS_RETPOLINE ||
+ mode == SPECTRE_V2_EIBRS_LFENCE;
}

static void __init
-spectre_v2_user_select_mitigation(enum spectre_v2_mitigation_cmd v2_cmd)
+spectre_v2_user_select_mitigation(void)
{
enum spectre_v2_user_mitigation mode = SPECTRE_V2_USER_NONE;
bool smt_possible = IS_ENABLED(CONFIG_SMP);
@@ -874,7 +990,7 @@ spectre_v2_user_select_mitigation(enum spectre_v2_mitigation_cmd v2_cmd)
cpu_smt_control == CPU_SMT_NOT_SUPPORTED)
smt_possible = false;

- cmd = spectre_v2_parse_user_cmdline(v2_cmd);
+ cmd = spectre_v2_parse_user_cmdline();
switch (cmd) {
case SPECTRE_V2_USER_CMD_NONE:
goto set_mode;
@@ -922,12 +1038,12 @@ spectre_v2_user_select_mitigation(enum spectre_v2_mitigation_cmd v2_cmd)
}

/*
- * If no STIBP, enhanced IBRS is enabled or SMT impossible, STIBP is not
- * required.
+ * If no STIBP, IBRS or enhanced IBRS is enabled, or SMT impossible,
+ * STIBP is not required.
*/
if (!boot_cpu_has(X86_FEATURE_STIBP) ||
!smt_possible ||
- spectre_v2_in_eibrs_mode(spectre_v2_enabled))
+ spectre_v2_in_ibrs_mode(spectre_v2_enabled))
return;

/*
@@ -952,6 +1068,7 @@ static const char * const spectre_v2_strings[] = {
[SPECTRE_V2_EIBRS] = "Mitigation: Enhanced IBRS",
[SPECTRE_V2_EIBRS_LFENCE] = "Mitigation: Enhanced IBRS + LFENCE",
[SPECTRE_V2_EIBRS_RETPOLINE] = "Mitigation: Enhanced IBRS + Retpolines",
+ [SPECTRE_V2_IBRS] = "Mitigation: IBRS",
};

static const struct {
@@ -969,6 +1086,7 @@ static const struct {
{ "eibrs,lfence", SPECTRE_V2_CMD_EIBRS_LFENCE, false },
{ "eibrs,retpoline", SPECTRE_V2_CMD_EIBRS_RETPOLINE, false },
{ "auto", SPECTRE_V2_CMD_AUTO, false },
+ { "ibrs", SPECTRE_V2_CMD_IBRS, false },
};

static void __init spec_v2_print_cond(const char *reason, bool secure)
@@ -1031,6 +1149,24 @@ static enum spectre_v2_mitigation_cmd __init spectre_v2_parse_cmdline(void)
return SPECTRE_V2_CMD_AUTO;
}

+ if (cmd == SPECTRE_V2_CMD_IBRS && boot_cpu_data.x86_vendor != X86_VENDOR_INTEL) {
+ pr_err("%s selected but not Intel CPU. Switching to AUTO select\n",
+ mitigation_options[i].option);
+ return SPECTRE_V2_CMD_AUTO;
+ }
+
+ if (cmd == SPECTRE_V2_CMD_IBRS && !boot_cpu_has(X86_FEATURE_IBRS)) {
+ pr_err("%s selected but CPU doesn't have IBRS. Switching to AUTO select\n",
+ mitigation_options[i].option);
+ return SPECTRE_V2_CMD_AUTO;
+ }
+
+ if (cmd == SPECTRE_V2_CMD_IBRS && boot_cpu_has(X86_FEATURE_XENPV)) {
+ pr_err("%s selected but running as XenPV guest. Switching to AUTO select\n",
+ mitigation_options[i].option);
+ return SPECTRE_V2_CMD_AUTO;
+ }
+
spec_v2_print_cond(mitigation_options[i].option,
mitigation_options[i].secure);
return cmd;
@@ -1046,6 +1182,22 @@ static enum spectre_v2_mitigation __init spectre_v2_select_retpoline(void)
return SPECTRE_V2_RETPOLINE;
}

+/* Disable in-kernel use of non-RSB RET predictors */
+static void __init spec_ctrl_disable_kernel_rrsba(void)
+{
+ u64 ia32_cap;
+
+ if (!boot_cpu_has(X86_FEATURE_RRSBA_CTRL))
+ return;
+
+ ia32_cap = x86_read_arch_cap_msr();
+
+ if (ia32_cap & ARCH_CAP_RRSBA) {
+ x86_spec_ctrl_base |= SPEC_CTRL_RRSBA_DIS_S;
+ write_spec_ctrl_current(x86_spec_ctrl_base, true);
+ }
+}
+
static void __init spectre_v2_determine_rsb_fill_type_at_vmexit(enum spectre_v2_mitigation mode)
{
/*
@@ -1070,10 +1222,6 @@ static void __init spectre_v2_determine_rsb_fill_type_at_vmexit(enum spectre_v2_
*/
switch (mode) {
case SPECTRE_V2_NONE:
- /* These modes already fill RSB at vmexit */
- case SPECTRE_V2_LFENCE:
- case SPECTRE_V2_RETPOLINE:
- case SPECTRE_V2_EIBRS_RETPOLINE:
return;

case SPECTRE_V2_EIBRS_LFENCE:
@@ -1083,6 +1231,14 @@ static void __init spectre_v2_determine_rsb_fill_type_at_vmexit(enum spectre_v2_
pr_info("Spectre v2 / PBRSB-eIBRS: Retire a single CALL on VMEXIT\n");
}
return;
+
+ case SPECTRE_V2_EIBRS_RETPOLINE:
+ case SPECTRE_V2_RETPOLINE:
+ case SPECTRE_V2_LFENCE:
+ case SPECTRE_V2_IBRS:
+ setup_force_cpu_cap(X86_FEATURE_RSB_VMEXIT);
+ pr_info("Spectre v2 / SpectreRSB : Filling RSB on VMEXIT\n");
+ return;
}

pr_warn_once("Unknown Spectre v2 mode, disabling RSB mitigation at VM exit");
@@ -1113,6 +1269,14 @@ static void __init spectre_v2_select_mitigation(void)
break;
}

+ if (boot_cpu_has_bug(X86_BUG_RETBLEED) &&
+ retbleed_cmd != RETBLEED_CMD_OFF &&
+ boot_cpu_has(X86_FEATURE_IBRS) &&
+ boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) {
+ mode = SPECTRE_V2_IBRS;
+ break;
+ }
+
mode = spectre_v2_select_retpoline();
break;

@@ -1129,6 +1293,10 @@ static void __init spectre_v2_select_mitigation(void)
mode = spectre_v2_select_retpoline();
break;

+ case SPECTRE_V2_CMD_IBRS:
+ mode = SPECTRE_V2_IBRS;
+ break;
+
case SPECTRE_V2_CMD_EIBRS:
mode = SPECTRE_V2_EIBRS;
break;
@@ -1145,10 +1313,9 @@ static void __init spectre_v2_select_mitigation(void)
if (mode == SPECTRE_V2_EIBRS && unprivileged_ebpf_enabled())
pr_err(SPECTRE_V2_EIBRS_EBPF_MSG);

- if (spectre_v2_in_eibrs_mode(mode)) {
- /* Force it so VMEXIT will restore correctly */
+ if (spectre_v2_in_ibrs_mode(mode)) {
x86_spec_ctrl_base |= SPEC_CTRL_IBRS;
- wrmsrl(MSR_IA32_SPEC_CTRL, x86_spec_ctrl_base);
+ write_spec_ctrl_current(x86_spec_ctrl_base, true);
}

switch (mode) {
@@ -1156,6 +1323,12 @@ static void __init spectre_v2_select_mitigation(void)
case SPECTRE_V2_EIBRS:
break;

+ case SPECTRE_V2_IBRS:
+ setup_force_cpu_cap(X86_FEATURE_KERNEL_IBRS);
+ if (boot_cpu_has(X86_FEATURE_IBRS_ENHANCED))
+ pr_warn(SPECTRE_V2_IBRS_PERF_MSG);
+ break;
+
case SPECTRE_V2_LFENCE:
case SPECTRE_V2_EIBRS_LFENCE:
setup_force_cpu_cap(X86_FEATURE_RETPOLINE_LFENCE);
@@ -1167,16 +1340,56 @@ static void __init spectre_v2_select_mitigation(void)
break;
}

+ /*
+ * Disable alternate RSB predictions in kernel when indirect CALLs and
+ * JMPs gets protection against BHI and Intramode-BTI, but RET
+ * prediction from a non-RSB predictor is still a risk.
+ */
+ if (mode == SPECTRE_V2_EIBRS_LFENCE ||
+ mode == SPECTRE_V2_EIBRS_RETPOLINE ||
+ mode == SPECTRE_V2_RETPOLINE)
+ spec_ctrl_disable_kernel_rrsba();
+
spectre_v2_enabled = mode;
pr_info("%s\n", spectre_v2_strings[mode]);

/*
- * If spectre v2 protection has been enabled, unconditionally fill
- * RSB during a context switch; this protects against two independent
- * issues:
+ * If Spectre v2 protection has been enabled, fill the RSB during a
+ * context switch. In general there are two types of RSB attacks
+ * across context switches, for which the CALLs/RETs may be unbalanced.
+ *
+ * 1) RSB underflow
+ *
+ * Some Intel parts have "bottomless RSB". When the RSB is empty,
+ * speculated return targets may come from the branch predictor,
+ * which could have a user-poisoned BTB or BHB entry.
+ *
+ * AMD has it even worse: *all* returns are speculated from the BTB,
+ * regardless of the state of the RSB.
+ *
+ * When IBRS or eIBRS is enabled, the "user -> kernel" attack
+ * scenario is mitigated by the IBRS branch prediction isolation
+ * properties, so the RSB buffer filling wouldn't be necessary to
+ * protect against this type of attack.
+ *
+ * The "user -> user" attack scenario is mitigated by RSB filling.
*
- * - RSB underflow (and switch to BTB) on Skylake+
- * - SpectreRSB variant of spectre v2 on X86_BUG_SPECTRE_V2 CPUs
+ * 2) Poisoned RSB entry
+ *
+ * If the 'next' in-kernel return stack is shorter than 'prev',
+ * 'next' could be tricked into speculating with a user-poisoned RSB
+ * entry.
+ *
+ * The "user -> kernel" attack scenario is mitigated by SMEP and
+ * eIBRS.
+ *
+ * The "user -> user" scenario, also known as SpectreBHB, requires
+ * RSB clearing.
+ *
+ * So to mitigate all cases, unconditionally fill RSB on context
+ * switches.
+ *
+ * FIXME: Is this pointless for retbleed-affected AMD?
*/
setup_force_cpu_cap(X86_FEATURE_RSB_CTXSW);
pr_info("Spectre v2 / SpectreRSB mitigation: Filling RSB on context switch\n");
@@ -1184,28 +1397,29 @@ static void __init spectre_v2_select_mitigation(void)
spectre_v2_determine_rsb_fill_type_at_vmexit(mode);

/*
- * Retpoline means the kernel is safe because it has no indirect
- * branches. Enhanced IBRS protects firmware too, so, enable restricted
- * speculation around firmware calls only when Enhanced IBRS isn't
- * supported.
+ * Retpoline protects the kernel, but doesn't protect firmware. IBRS
+ * and Enhanced IBRS protect firmware too, so enable IBRS around
+ * firmware calls only when IBRS / Enhanced IBRS aren't otherwise
+ * enabled.
*
* Use "mode" to check Enhanced IBRS instead of boot_cpu_has(), because
* the user might select retpoline on the kernel command line and if
* the CPU supports Enhanced IBRS, kernel might un-intentionally not
* enable IBRS around firmware calls.
*/
- if (boot_cpu_has(X86_FEATURE_IBRS) && !spectre_v2_in_eibrs_mode(mode)) {
+ if (boot_cpu_has(X86_FEATURE_IBRS) && !spectre_v2_in_ibrs_mode(mode)) {
setup_force_cpu_cap(X86_FEATURE_USE_IBRS_FW);
pr_info("Enabling Restricted Speculation for firmware calls\n");
}

/* Set up IBPB and STIBP depending on the general spectre V2 command */
- spectre_v2_user_select_mitigation(cmd);
+ spectre_v2_cmd = cmd;
}

static void update_stibp_msr(void * __unused)
{
- wrmsrl(MSR_IA32_SPEC_CTRL, x86_spec_ctrl_base);
+ u64 val = spec_ctrl_current() | (x86_spec_ctrl_base & SPEC_CTRL_STIBP);
+ write_spec_ctrl_current(val, true);
}

/* Update x86_spec_ctrl_base in case SMT state changed. */
@@ -1421,16 +1635,6 @@ static enum ssb_mitigation __init __ssb_select_mitigation(void)
break;
}

- /*
- * If SSBD is controlled by the SPEC_CTRL MSR, then set the proper
- * bit in the mask to allow guests to use the mitigation even in the
- * case where the host does not enable it.
- */
- if (static_cpu_has(X86_FEATURE_SPEC_CTRL_SSBD) ||
- static_cpu_has(X86_FEATURE_AMD_SSBD)) {
- x86_spec_ctrl_mask |= SPEC_CTRL_SSBD;
- }
-
/*
* We have three CPU feature flags that are in play here:
* - X86_BUG_SPEC_STORE_BYPASS - CPU is susceptible.
@@ -1448,7 +1652,7 @@ static enum ssb_mitigation __init __ssb_select_mitigation(void)
x86_amd_ssb_disable();
} else {
x86_spec_ctrl_base |= SPEC_CTRL_SSBD;
- wrmsrl(MSR_IA32_SPEC_CTRL, x86_spec_ctrl_base);
+ write_spec_ctrl_current(x86_spec_ctrl_base, true);
}
}

@@ -1665,7 +1869,7 @@ int arch_prctl_spec_ctrl_get(struct task_struct *task, unsigned long which)
void x86_spec_ctrl_setup_ap(void)
{
if (boot_cpu_has(X86_FEATURE_MSR_SPEC_CTRL))
- wrmsrl(MSR_IA32_SPEC_CTRL, x86_spec_ctrl_base);
+ write_spec_ctrl_current(x86_spec_ctrl_base, true);

if (ssb_mode == SPEC_STORE_BYPASS_DISABLE)
x86_amd_ssb_disable();
@@ -1900,7 +2104,7 @@ static ssize_t mmio_stale_data_show_state(char *buf)

static char *stibp_state(void)
{
- if (spectre_v2_in_eibrs_mode(spectre_v2_enabled))
+ if (spectre_v2_in_ibrs_mode(spectre_v2_enabled))
return "";

switch (spectre_v2_user_stibp) {
@@ -1934,7 +2138,7 @@ static char *pbrsb_eibrs_state(void)
{
if (boot_cpu_has_bug(X86_BUG_EIBRS_PBRSB)) {
if (boot_cpu_has(X86_FEATURE_RSB_VMEXIT_LITE) ||
- boot_cpu_has(X86_FEATURE_RETPOLINE))
+ boot_cpu_has(X86_FEATURE_RSB_VMEXIT))
return ", PBRSB-eIBRS: SW sequence";
else
return ", PBRSB-eIBRS: Vulnerable";
@@ -1970,6 +2174,11 @@ static ssize_t srbds_show_state(char *buf)
return sprintf(buf, "%s\n", srbds_strings[srbds_mitigation]);
}

+static ssize_t retbleed_show_state(char *buf)
+{
+ return sprintf(buf, "%s\n", retbleed_strings[retbleed_mitigation]);
+}
+
static ssize_t cpu_show_common(struct device *dev, struct device_attribute *attr,
char *buf, unsigned int bug)
{
@@ -2016,6 +2225,9 @@ static ssize_t cpu_show_common(struct device *dev, struct device_attribute *attr
case X86_BUG_MMIO_UNKNOWN:
return mmio_stale_data_show_state(buf);

+ case X86_BUG_RETBLEED:
+ return retbleed_show_state(buf);
+
default:
break;
}
@@ -2075,4 +2287,9 @@ ssize_t cpu_show_mmio_stale_data(struct device *dev, struct device_attribute *at
else
return cpu_show_common(dev, attr, buf, X86_BUG_MMIO_STALE_DATA);
}
+
+ssize_t cpu_show_retbleed(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ return cpu_show_common(dev, attr, buf, X86_BUG_RETBLEED);
+}
#endif
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 59413e741ecf..5e1e32f1086b 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -1102,48 +1102,60 @@ static const __initconst struct x86_cpu_id cpu_vuln_whitelist[] = {
{}
};

+#define VULNBL(vendor, family, model, blacklist) \
+ X86_MATCH_VENDOR_FAM_MODEL(vendor, family, model, blacklist)
+
#define VULNBL_INTEL_STEPPINGS(model, steppings, issues) \
X86_MATCH_VENDOR_FAM_MODEL_STEPPINGS_FEATURE(INTEL, 6, \
INTEL_FAM6_##model, steppings, \
X86_FEATURE_ANY, issues)

+#define VULNBL_AMD(family, blacklist) \
+ VULNBL(AMD, family, X86_MODEL_ANY, blacklist)
+
+#define VULNBL_HYGON(family, blacklist) \
+ VULNBL(HYGON, family, X86_MODEL_ANY, blacklist)
+
#define SRBDS BIT(0)
/* CPU is affected by X86_BUG_MMIO_STALE_DATA */
#define MMIO BIT(1)
/* CPU is affected by Shared Buffers Data Sampling (SBDS), a variant of X86_BUG_MMIO_STALE_DATA */
#define MMIO_SBDS BIT(2)
+/* CPU is affected by RETbleed, speculating where you would not expect it */
+#define RETBLEED BIT(3)

static const struct x86_cpu_id cpu_vuln_blacklist[] __initconst = {
VULNBL_INTEL_STEPPINGS(IVYBRIDGE, X86_STEPPING_ANY, SRBDS),
VULNBL_INTEL_STEPPINGS(HASWELL, X86_STEPPING_ANY, SRBDS),
VULNBL_INTEL_STEPPINGS(HASWELL_L, X86_STEPPING_ANY, SRBDS),
VULNBL_INTEL_STEPPINGS(HASWELL_G, X86_STEPPING_ANY, SRBDS),
- VULNBL_INTEL_STEPPINGS(HASWELL_X, BIT(2) | BIT(4), MMIO),
- VULNBL_INTEL_STEPPINGS(BROADWELL_D, X86_STEPPINGS(0x3, 0x5), MMIO),
+ VULNBL_INTEL_STEPPINGS(HASWELL_X, X86_STEPPING_ANY, MMIO),
+ VULNBL_INTEL_STEPPINGS(BROADWELL_D, X86_STEPPING_ANY, MMIO),
VULNBL_INTEL_STEPPINGS(BROADWELL_G, X86_STEPPING_ANY, SRBDS),
VULNBL_INTEL_STEPPINGS(BROADWELL_X, X86_STEPPING_ANY, MMIO),
VULNBL_INTEL_STEPPINGS(BROADWELL, X86_STEPPING_ANY, SRBDS),
- VULNBL_INTEL_STEPPINGS(SKYLAKE_L, X86_STEPPINGS(0x3, 0x3), SRBDS | MMIO),
- VULNBL_INTEL_STEPPINGS(SKYLAKE_L, X86_STEPPING_ANY, SRBDS),
- VULNBL_INTEL_STEPPINGS(SKYLAKE_X, BIT(3) | BIT(4) | BIT(6) |
- BIT(7) | BIT(0xB), MMIO),
- VULNBL_INTEL_STEPPINGS(SKYLAKE, X86_STEPPINGS(0x3, 0x3), SRBDS | MMIO),
- VULNBL_INTEL_STEPPINGS(SKYLAKE, X86_STEPPING_ANY, SRBDS),
- VULNBL_INTEL_STEPPINGS(KABYLAKE_L, X86_STEPPINGS(0x9, 0xC), SRBDS | MMIO),
- VULNBL_INTEL_STEPPINGS(KABYLAKE_L, X86_STEPPINGS(0x0, 0x8), SRBDS),
- VULNBL_INTEL_STEPPINGS(KABYLAKE, X86_STEPPINGS(0x9, 0xD), SRBDS | MMIO),
- VULNBL_INTEL_STEPPINGS(KABYLAKE, X86_STEPPINGS(0x0, 0x8), SRBDS),
- VULNBL_INTEL_STEPPINGS(ICELAKE_L, X86_STEPPINGS(0x5, 0x5), MMIO | MMIO_SBDS),
- VULNBL_INTEL_STEPPINGS(ICELAKE_D, X86_STEPPINGS(0x1, 0x1), MMIO),
- VULNBL_INTEL_STEPPINGS(ICELAKE_X, X86_STEPPINGS(0x4, 0x6), MMIO),
- VULNBL_INTEL_STEPPINGS(COMETLAKE, BIT(2) | BIT(3) | BIT(5), MMIO | MMIO_SBDS),
- VULNBL_INTEL_STEPPINGS(COMETLAKE_L, X86_STEPPINGS(0x1, 0x1), MMIO | MMIO_SBDS),
- VULNBL_INTEL_STEPPINGS(COMETLAKE_L, X86_STEPPINGS(0x0, 0x0), MMIO),
- VULNBL_INTEL_STEPPINGS(LAKEFIELD, X86_STEPPINGS(0x1, 0x1), MMIO | MMIO_SBDS),
- VULNBL_INTEL_STEPPINGS(ROCKETLAKE, X86_STEPPINGS(0x1, 0x1), MMIO),
- VULNBL_INTEL_STEPPINGS(ATOM_TREMONT, X86_STEPPINGS(0x1, 0x1), MMIO | MMIO_SBDS),
+ VULNBL_INTEL_STEPPINGS(SKYLAKE_L, X86_STEPPING_ANY, SRBDS | MMIO | RETBLEED),
+ VULNBL_INTEL_STEPPINGS(SKYLAKE_X, X86_STEPPING_ANY, MMIO | RETBLEED),
+ VULNBL_INTEL_STEPPINGS(SKYLAKE, X86_STEPPING_ANY, SRBDS | MMIO | RETBLEED),
+ VULNBL_INTEL_STEPPINGS(KABYLAKE_L, X86_STEPPING_ANY, SRBDS | MMIO | RETBLEED),
+ VULNBL_INTEL_STEPPINGS(KABYLAKE, X86_STEPPING_ANY, SRBDS | MMIO | RETBLEED),
+ VULNBL_INTEL_STEPPINGS(CANNONLAKE_L, X86_STEPPING_ANY, RETBLEED),
+ VULNBL_INTEL_STEPPINGS(ICELAKE_L, X86_STEPPING_ANY, MMIO | MMIO_SBDS | RETBLEED),
+ VULNBL_INTEL_STEPPINGS(ICELAKE_D, X86_STEPPING_ANY, MMIO),
+ VULNBL_INTEL_STEPPINGS(ICELAKE_X, X86_STEPPING_ANY, MMIO),
+ VULNBL_INTEL_STEPPINGS(COMETLAKE, X86_STEPPING_ANY, MMIO | MMIO_SBDS | RETBLEED),
+ VULNBL_INTEL_STEPPINGS(COMETLAKE_L, X86_STEPPINGS(0x0, 0x0), MMIO | RETBLEED),
+ VULNBL_INTEL_STEPPINGS(COMETLAKE_L, X86_STEPPING_ANY, MMIO | MMIO_SBDS | RETBLEED),
+ VULNBL_INTEL_STEPPINGS(LAKEFIELD, X86_STEPPING_ANY, MMIO | MMIO_SBDS | RETBLEED),
+ VULNBL_INTEL_STEPPINGS(ROCKETLAKE, X86_STEPPING_ANY, MMIO | RETBLEED),
+ VULNBL_INTEL_STEPPINGS(ATOM_TREMONT, X86_STEPPING_ANY, MMIO | MMIO_SBDS),
VULNBL_INTEL_STEPPINGS(ATOM_TREMONT_D, X86_STEPPING_ANY, MMIO),
- VULNBL_INTEL_STEPPINGS(ATOM_TREMONT_L, X86_STEPPINGS(0x0, 0x0), MMIO | MMIO_SBDS),
+ VULNBL_INTEL_STEPPINGS(ATOM_TREMONT_L, X86_STEPPING_ANY, MMIO | MMIO_SBDS),
+
+ VULNBL_AMD(0x15, RETBLEED),
+ VULNBL_AMD(0x16, RETBLEED),
+ VULNBL_AMD(0x17, RETBLEED),
+ VULNBL_HYGON(0x18, RETBLEED),
{}
};

@@ -1251,6 +1263,11 @@ static void __init cpu_set_bug_bits(struct cpuinfo_x86 *c)
setup_force_cpu_bug(X86_BUG_MMIO_UNKNOWN);
}

+ if (!cpu_has(c, X86_FEATURE_BTC_NO)) {
+ if (cpu_matches(cpu_vuln_blacklist, RETBLEED) || (ia32_cap & ARCH_CAP_RSBA))
+ setup_force_cpu_bug(X86_BUG_RETBLEED);
+ }
+
if (cpu_has(c, X86_FEATURE_IBRS_ENHANCED) &&
!cpu_matches(cpu_vuln_whitelist, NO_EIBRS_PBRSB) &&
!(ia32_cap & ARCH_CAP_PBRSB_NO))
diff --git a/arch/x86/kernel/cpu/match.c b/arch/x86/kernel/cpu/match.c
index 2f163e6646b6..ad6776081e60 100644
--- a/arch/x86/kernel/cpu/match.c
+++ b/arch/x86/kernel/cpu/match.c
@@ -16,12 +16,17 @@
* respective wildcard entries.
*
* A typical table entry would be to match a specific CPU
- * { X86_VENDOR_INTEL, 6, 0x12 }
- * or to match a specific CPU feature
- * { X86_FEATURE_MATCH(X86_FEATURE_FOOBAR) }
+ *
+ * X86_MATCH_VENDOR_FAM_MODEL_FEATURE(INTEL, 6, INTEL_FAM6_BROADWELL,
+ * X86_FEATURE_ANY, NULL);
*
* Fields can be wildcarded with %X86_VENDOR_ANY, %X86_FAMILY_ANY,
- * %X86_MODEL_ANY, %X86_FEATURE_ANY or 0 (except for vendor)
+ * %X86_MODEL_ANY, %X86_FEATURE_ANY (except for vendor)
+ *
+ * asm/cpu_device_id.h contains a set of useful macros which are shortcuts
+ * for various common selections. The above can be shortened to:
+ *
+ * X86_MATCH_INTEL_FAM6_MODEL(BROADWELL, NULL);
*
* Arrays used to match for this should also be declared using
* MODULE_DEVICE_TABLE(x86cpu, ...)
diff --git a/arch/x86/kernel/cpu/scattered.c b/arch/x86/kernel/cpu/scattered.c
index 53004dbd55c4..a03e309a0ac5 100644
--- a/arch/x86/kernel/cpu/scattered.c
+++ b/arch/x86/kernel/cpu/scattered.c
@@ -26,6 +26,7 @@ struct cpuid_bit {
static const struct cpuid_bit cpuid_bits[] = {
{ X86_FEATURE_APERFMPERF, CPUID_ECX, 0, 0x00000006, 0 },
{ X86_FEATURE_EPB, CPUID_ECX, 3, 0x00000006, 0 },
+ { X86_FEATURE_RRSBA_CTRL, CPUID_EDX, 2, 0x00000007, 2 },
{ X86_FEATURE_CQM_LLC, CPUID_EDX, 1, 0x0000000f, 0 },
{ X86_FEATURE_CQM_OCCUP_LLC, CPUID_EDX, 0, 0x0000000f, 1 },
{ X86_FEATURE_CQM_MBM_TOTAL, CPUID_EDX, 1, 0x0000000f, 1 },
diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index 068715a52ac1..87cfd2ee9ca0 100644
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -449,7 +449,7 @@ static __always_inline void __speculation_ctrl_update(unsigned long tifp,
}

if (updmsr)
- wrmsrl(MSR_IA32_SPEC_CTRL, msr);
+ write_spec_ctrl_current(msr, false);
}

static unsigned long speculation_ctrl_update_tif(struct task_struct *tsk)
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 1efcc7d4bc88..3db407e3c416 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -47,6 +47,7 @@
#include <asm/kvm_para.h>
#include <asm/irq_remapping.h>
#include <asm/spec-ctrl.h>
+#include <asm/cpu_device_id.h>

#include <asm/virtext.h>
#include "trace.h"
diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index 34ee4835b017..a7b62a00913e 100644
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -11,6 +11,7 @@
#include "mmu.h"
#include "nested.h"
#include "trace.h"
+#include "vmx.h"
#include "x86.h"

static bool __read_mostly enable_shadow_vmcs = 1;
@@ -2863,35 +2864,8 @@ static int nested_vmx_check_vmentry_hw(struct kvm_vcpu *vcpu)
vmx->loaded_vmcs->host_state.cr4 = cr4;
}

- asm(
- "sub $%c[wordsize], %%" _ASM_SP "\n\t" /* temporarily adjust RSP for CALL */
- "cmp %%" _ASM_SP ", %c[host_state_rsp](%[loaded_vmcs]) \n\t"
- "je 1f \n\t"
- __ex("vmwrite %%" _ASM_SP ", %[HOST_RSP]") "\n\t"
- "mov %%" _ASM_SP ", %c[host_state_rsp](%[loaded_vmcs]) \n\t"
- "1: \n\t"
- "add $%c[wordsize], %%" _ASM_SP "\n\t" /* un-adjust RSP */
-
- /* Check if vmlaunch or vmresume is needed */
- "cmpb $0, %c[launched](%[loaded_vmcs])\n\t"
-
- /*
- * VMLAUNCH and VMRESUME clear RFLAGS.{CF,ZF} on VM-Exit, set
- * RFLAGS.CF on VM-Fail Invalid and set RFLAGS.ZF on VM-Fail
- * Valid. vmx_vmenter() directly "returns" RFLAGS, and so the
- * results of VM-Enter is captured via CC_{SET,OUT} to vm_fail.
- */
- "call vmx_vmenter\n\t"
-
- CC_SET(be)
- : ASM_CALL_CONSTRAINT, CC_OUT(be) (vm_fail)
- : [HOST_RSP]"r"((unsigned long)HOST_RSP),
- [loaded_vmcs]"r"(vmx->loaded_vmcs),
- [launched]"i"(offsetof(struct loaded_vmcs, launched)),
- [host_state_rsp]"i"(offsetof(struct loaded_vmcs, host_state.rsp)),
- [wordsize]"i"(sizeof(ulong))
- : "memory"
- );
+ vm_fail = __vmx_vcpu_run(vmx, (unsigned long *)&vcpu->arch.regs,
+ __vmx_vcpu_run_flags(vmx));

if (vmx->msr_autoload.host.nr)
vmcs_write32(VM_EXIT_MSR_LOAD_COUNT, vmx->msr_autoload.host.nr);
diff --git a/arch/x86/kvm/vmx/run_flags.h b/arch/x86/kvm/vmx/run_flags.h
new file mode 100644
index 000000000000..edc3f16cc189
--- /dev/null
+++ b/arch/x86/kvm/vmx/run_flags.h
@@ -0,0 +1,8 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __KVM_X86_VMX_RUN_FLAGS_H
+#define __KVM_X86_VMX_RUN_FLAGS_H
+
+#define VMX_RUN_VMRESUME (1 << 0)
+#define VMX_RUN_SAVE_SPEC_CTRL (1 << 1)
+
+#endif /* __KVM_X86_VMX_RUN_FLAGS_H */
diff --git a/arch/x86/kvm/vmx/vmenter.S b/arch/x86/kvm/vmx/vmenter.S
index 946d9205c3b6..2850670c38bb 100644
--- a/arch/x86/kvm/vmx/vmenter.S
+++ b/arch/x86/kvm/vmx/vmenter.S
@@ -4,6 +4,7 @@
#include <asm/bitsperlong.h>
#include <asm/kvm_vcpu_regs.h>
#include <asm/nospec-branch.h>
+#include "run_flags.h"

#define WORD_SIZE (BITS_PER_LONG / 8)

@@ -29,78 +30,12 @@

.text

-/**
- * vmx_vmenter - VM-Enter the current loaded VMCS
- *
- * %RFLAGS.ZF: !VMCS.LAUNCHED, i.e. controls VMLAUNCH vs. VMRESUME
- *
- * Returns:
- * %RFLAGS.CF is set on VM-Fail Invalid
- * %RFLAGS.ZF is set on VM-Fail Valid
- * %RFLAGS.{CF,ZF} are cleared on VM-Success, i.e. VM-Exit
- *
- * Note that VMRESUME/VMLAUNCH fall-through and return directly if
- * they VM-Fail, whereas a successful VM-Enter + VM-Exit will jump
- * to vmx_vmexit.
- */
-ENTRY(vmx_vmenter)
- /* EFLAGS.ZF is set if VMCS.LAUNCHED == 0 */
- je 2f
-
-1: vmresume
- ret
-
-2: vmlaunch
- ret
-
-3: cmpb $0, kvm_rebooting
- je 4f
- ret
-4: ud2
-
- .pushsection .fixup, "ax"
-5: jmp 3b
- .popsection
-
- _ASM_EXTABLE(1b, 5b)
- _ASM_EXTABLE(2b, 5b)
-
-ENDPROC(vmx_vmenter)
-
-/**
- * vmx_vmexit - Handle a VMX VM-Exit
- *
- * Returns:
- * %RFLAGS.{CF,ZF} are cleared on VM-Success, i.e. VM-Exit
- *
- * This is vmx_vmenter's partner in crime. On a VM-Exit, control will jump
- * here after hardware loads the host's state, i.e. this is the destination
- * referred to by VMCS.HOST_RIP.
- */
-ENTRY(vmx_vmexit)
-#ifdef CONFIG_RETPOLINE
- ALTERNATIVE "jmp .Lvmexit_skip_rsb", "", X86_FEATURE_RETPOLINE
- /* Preserve guest's RAX, it's used to stuff the RSB. */
- push %_ASM_AX
-
- /* IMPORTANT: Stuff the RSB immediately after VM-Exit, before RET! */
- FILL_RETURN_BUFFER %_ASM_AX, RSB_CLEAR_LOOPS, X86_FEATURE_RETPOLINE
-
- /* Clear RFLAGS.CF and RFLAGS.ZF to preserve VM-Exit, i.e. !VM-Fail. */
- or $1, %_ASM_AX
-
- pop %_ASM_AX
-.Lvmexit_skip_rsb:
-#endif
- ISSUE_UNBALANCED_RET_GUARD X86_FEATURE_RSB_VMEXIT_LITE
- ret
-ENDPROC(vmx_vmexit)
-
/**
* __vmx_vcpu_run - Run a vCPU via a transition to VMX guest mode
- * @vmx: struct vcpu_vmx * (forwarded to vmx_update_host_rsp)
+ * @vmx: struct vcpu_vmx *
* @regs: unsigned long * (to guest registers)
- * @launched: %true if the VMCS has been launched
+ * @flags: VMX_RUN_VMRESUME: use VMRESUME instead of VMLAUNCH
+ * VMX_RUN_SAVE_SPEC_CTRL: save guest SPEC_CTRL into vmx->spec_ctrl
*
* Returns:
* 0 on VM-Exit, 1 on VM-Fail
@@ -119,24 +54,29 @@ ENTRY(__vmx_vcpu_run)
#endif
push %_ASM_BX

+ /* Save @vmx for SPEC_CTRL handling */
+ push %_ASM_ARG1
+
+ /* Save @flags for SPEC_CTRL handling */
+ push %_ASM_ARG3
+
/*
* Save @regs, _ASM_ARG2 may be modified by vmx_update_host_rsp() and
* @regs is needed after VM-Exit to save the guest's register values.
*/
push %_ASM_ARG2

- /* Copy @launched to BL, _ASM_ARG3 is volatile. */
+ /* Copy @flags to BL, _ASM_ARG3 is volatile. */
mov %_ASM_ARG3B, %bl

- /* Adjust RSP to account for the CALL to vmx_vmenter(). */
- lea -WORD_SIZE(%_ASM_SP), %_ASM_ARG2
+ lea (%_ASM_SP), %_ASM_ARG2
call vmx_update_host_rsp

/* Load @regs to RAX. */
mov (%_ASM_SP), %_ASM_AX

/* Check if vmlaunch or vmresume is needed */
- cmpb $0, %bl
+ testb $VMX_RUN_VMRESUME, %bl

/* Load guest registers. Don't clobber flags. */
mov VCPU_RBX(%_ASM_AX), %_ASM_BX
@@ -158,11 +98,25 @@ ENTRY(__vmx_vcpu_run)
/* Load guest RAX. This kills the @regs pointer! */
mov VCPU_RAX(%_ASM_AX), %_ASM_AX

- /* Enter guest mode */
- call vmx_vmenter
+ /* Check EFLAGS.ZF from 'testb' above */
+ jz .Lvmlaunch

- /* Jump on VM-Fail. */
- jbe 2f
+/*
+ * If VMRESUME/VMLAUNCH and corresponding vmexit succeed, execution resumes at
+ * the 'vmx_vmexit' label below.
+ */
+.Lvmresume:
+ vmresume
+ jmp .Lvmfail
+
+.Lvmlaunch:
+ vmlaunch
+ jmp .Lvmfail
+
+ _ASM_EXTABLE(.Lvmresume, .Lfixup)
+ _ASM_EXTABLE(.Lvmlaunch, .Lfixup)
+
+SYM_INNER_LABEL(vmx_vmexit, SYM_L_GLOBAL)

/* Temporarily save guest's RAX. */
push %_ASM_AX
@@ -189,19 +143,21 @@ ENTRY(__vmx_vcpu_run)
mov %r15, VCPU_R15(%_ASM_AX)
#endif

- /* Clear RAX to indicate VM-Exit (as opposed to VM-Fail). */
- xor %eax, %eax
+ /* Clear return value to indicate VM-Exit (as opposed to VM-Fail). */
+ xor %ebx, %ebx

+.Lclear_regs:
/*
- * Clear all general purpose registers except RSP and RAX to prevent
+ * Clear all general purpose registers except RSP and RBX to prevent
* speculative use of the guest's values, even those that are reloaded
* via the stack. In theory, an L1 cache miss when restoring registers
* could lead to speculative execution with the guest's values.
* Zeroing XORs are dirt cheap, i.e. the extra paranoia is essentially
* free. RSP and RAX are exempt as RSP is restored by hardware during
- * VM-Exit and RAX is explicitly loaded with 0 or 1 to return VM-Fail.
+ * VM-Exit and RBX is explicitly loaded with 0 or 1 to hold the return
+ * value.
*/
-1: xor %ebx, %ebx
+ xor %eax, %eax
xor %ecx, %ecx
xor %edx, %edx
xor %esi, %esi
@@ -220,8 +176,32 @@ ENTRY(__vmx_vcpu_run)

/* "POP" @regs. */
add $WORD_SIZE, %_ASM_SP
- pop %_ASM_BX

+ /*
+ * IMPORTANT: RSB filling and SPEC_CTRL handling must be done before
+ * the first unbalanced RET after vmexit!
+ *
+ * For retpoline or IBRS, RSB filling is needed to prevent poisoned RSB
+ * entries and (in some cases) RSB underflow.
+ *
+ * eIBRS has its own protection against poisoned RSB, so it doesn't
+ * need the RSB filling sequence. But it does need to be enabled, and a
+ * single call to retire, before the first unbalanced RET.
+ */
+
+ FILL_RETURN_BUFFER %_ASM_CX, RSB_CLEAR_LOOPS, X86_FEATURE_RSB_VMEXIT,\
+ X86_FEATURE_RSB_VMEXIT_LITE
+
+
+ pop %_ASM_ARG2 /* @flags */
+ pop %_ASM_ARG1 /* @vmx */
+
+ call vmx_spec_ctrl_restore_host
+
+ /* Put return value in AX */
+ mov %_ASM_BX, %_ASM_AX
+
+ pop %_ASM_BX
#ifdef CONFIG_X86_64
pop %r12
pop %r13
@@ -234,11 +214,20 @@ ENTRY(__vmx_vcpu_run)
pop %_ASM_BP
ret

- /* VM-Fail. Out-of-line to avoid a taken Jcc after VM-Exit. */
-2: mov $1, %eax
- jmp 1b
+.Lfixup:
+ cmpb $0, kvm_rebooting
+ jne .Lvmfail
+ ud2
+.Lvmfail:
+ /* VM-Fail: set return value to 1 */
+ mov $1, %_ASM_BX
+ jmp .Lclear_regs
+
ENDPROC(__vmx_vcpu_run)

+
+.section .text, "ax"
+
/**
* vmread_error_trampoline - Trampoline from inline asm to vmread_error()
* @field: VMCS field encoding that failed
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 4bd1bf6214ee..d522c9de41df 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -31,6 +31,7 @@
#include <asm/apic.h>
#include <asm/asm.h>
#include <asm/cpu.h>
+#include <asm/cpu_device_id.h>
#include <asm/debugreg.h>
#include <asm/desc.h>
#include <asm/fpu/internal.h>
@@ -358,9 +359,9 @@ static __always_inline void vmx_disable_fb_clear(struct vcpu_vmx *vmx)
if (!vmx->disable_fb_clear)
return;

- rdmsrl(MSR_IA32_MCU_OPT_CTRL, msr);
+ msr = __rdmsr(MSR_IA32_MCU_OPT_CTRL);
msr |= FB_CLEAR_DIS;
- wrmsrl(MSR_IA32_MCU_OPT_CTRL, msr);
+ native_wrmsrl(MSR_IA32_MCU_OPT_CTRL, msr);
/* Cache the MSR value to avoid reading it later */
vmx->msr_ia32_mcu_opt_ctrl = msr;
}
@@ -371,7 +372,7 @@ static __always_inline void vmx_enable_fb_clear(struct vcpu_vmx *vmx)
return;

vmx->msr_ia32_mcu_opt_ctrl &= ~FB_CLEAR_DIS;
- wrmsrl(MSR_IA32_MCU_OPT_CTRL, vmx->msr_ia32_mcu_opt_ctrl);
+ native_wrmsrl(MSR_IA32_MCU_OPT_CTRL, vmx->msr_ia32_mcu_opt_ctrl);
}

static void vmx_update_fb_clear_dis(struct kvm_vcpu *vcpu, struct vcpu_vmx *vmx)
@@ -862,6 +863,24 @@ static bool msr_write_intercepted(struct vcpu_vmx *vmx, u32 msr)
return true;
}

+unsigned int __vmx_vcpu_run_flags(struct vcpu_vmx *vmx)
+{
+ unsigned int flags = 0;
+
+ if (vmx->loaded_vmcs->launched)
+ flags |= VMX_RUN_VMRESUME;
+
+ /*
+ * If writes to the SPEC_CTRL MSR aren't intercepted, the guest is free
+ * to change it directly without causing a vmexit. In that case read
+ * it after vmexit and store it in vmx->spec_ctrl.
+ */
+ if (unlikely(!msr_write_intercepted(vmx, MSR_IA32_SPEC_CTRL)))
+ flags |= VMX_RUN_SAVE_SPEC_CTRL;
+
+ return flags;
+}
+
static void clear_atomic_switch_msr_special(struct vcpu_vmx *vmx,
unsigned long entry, unsigned long exit)
{
@@ -6539,7 +6558,30 @@ void vmx_update_host_rsp(struct vcpu_vmx *vmx, unsigned long host_rsp)
}
}

-bool __vmx_vcpu_run(struct vcpu_vmx *vmx, unsigned long *regs, bool launched);
+void noinstr vmx_spec_ctrl_restore_host(struct vcpu_vmx *vmx,
+ unsigned int flags)
+{
+ u64 hostval = this_cpu_read(x86_spec_ctrl_current);
+
+ if (!cpu_feature_enabled(X86_FEATURE_MSR_SPEC_CTRL))
+ return;
+
+ if (flags & VMX_RUN_SAVE_SPEC_CTRL)
+ vmx->spec_ctrl = __rdmsr(MSR_IA32_SPEC_CTRL);
+
+ /*
+ * If the guest/host SPEC_CTRL values differ, restore the host value.
+ *
+ * For legacy IBRS, the IBRS bit always needs to be written after
+ * transitioning from a less privileged predictor mode, regardless of
+ * whether the guest/host values differ.
+ */
+ if (cpu_feature_enabled(X86_FEATURE_KERNEL_IBRS) ||
+ vmx->spec_ctrl != hostval)
+ native_wrmsrl(MSR_IA32_SPEC_CTRL, hostval);
+
+ barrier_nospec();
+}

static void vmx_vcpu_run(struct kvm_vcpu *vcpu)
{
@@ -6628,32 +6670,12 @@ static void vmx_vcpu_run(struct kvm_vcpu *vcpu)
write_cr2(vcpu->arch.cr2);

vmx->fail = __vmx_vcpu_run(vmx, (unsigned long *)&vcpu->arch.regs,
- vmx->loaded_vmcs->launched);
+ __vmx_vcpu_run_flags(vmx));

vcpu->arch.cr2 = read_cr2();

vmx_enable_fb_clear(vmx);

- /*
- * We do not use IBRS in the kernel. If this vCPU has used the
- * SPEC_CTRL MSR it may have left it on; save the value and
- * turn it off. This is much more efficient than blindly adding
- * it to the atomic save/restore list. Especially as the former
- * (Saving guest MSRs on vmexit) doesn't even exist in KVM.
- *
- * For non-nested case:
- * If the L01 MSR bitmap does not intercept the MSR, then we need to
- * save it.
- *
- * For nested case:
- * If the L02 MSR bitmap does not intercept the MSR, then we need to
- * save it.
- */
- if (unlikely(!msr_write_intercepted(vmx, MSR_IA32_SPEC_CTRL)))
- vmx->spec_ctrl = native_read_msr(MSR_IA32_SPEC_CTRL);
-
- x86_spec_ctrl_restore_host(vmx->spec_ctrl, 0);
-
/* All fields are clean at this point */
if (static_branch_unlikely(&enable_evmcs))
current_evmcs->hv_clean_fields |=
diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h
index 7a3362ab5986..4d5be4610af8 100644
--- a/arch/x86/kvm/vmx/vmx.h
+++ b/arch/x86/kvm/vmx/vmx.h
@@ -10,6 +10,7 @@
#include "capabilities.h"
#include "ops.h"
#include "vmcs.h"
+#include "run_flags.h"

extern const u32 vmx_msr_index[];
extern u64 host_efer;
@@ -336,6 +337,10 @@ void vmx_set_virtual_apic_mode(struct kvm_vcpu *vcpu);
struct shared_msr_entry *find_msr_entry(struct vcpu_vmx *vmx, u32 msr);
void pt_update_intercept_for_msr(struct vcpu_vmx *vmx);
void vmx_update_host_rsp(struct vcpu_vmx *vmx, unsigned long host_rsp);
+void vmx_spec_ctrl_restore_host(struct vcpu_vmx *vmx, unsigned int flags);
+unsigned int __vmx_vcpu_run_flags(struct vcpu_vmx *vmx);
+bool __vmx_vcpu_run(struct vcpu_vmx *vmx, unsigned long *regs,
+ unsigned int flags);

#define POSTED_INTR_ON 0
#define POSTED_INTR_SN 1
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index d0b297583df8..c431a34522d6 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -10329,9 +10329,9 @@ void kvm_arch_end_assignment(struct kvm *kvm)
}
EXPORT_SYMBOL_GPL(kvm_arch_end_assignment);

-bool kvm_arch_has_assigned_device(struct kvm *kvm)
+bool noinstr kvm_arch_has_assigned_device(struct kvm *kvm)
{
- return atomic_read(&kvm->arch.assigned_device_count);
+ return arch_atomic_read(&kvm->arch.assigned_device_count);
}
EXPORT_SYMBOL_GPL(kvm_arch_has_assigned_device);

diff --git a/drivers/base/cpu.c b/drivers/base/cpu.c
index 9b5edf1dfe9e..7000c836951c 100644
--- a/drivers/base/cpu.c
+++ b/drivers/base/cpu.c
@@ -574,6 +574,12 @@ ssize_t __weak cpu_show_mmio_stale_data(struct device *dev,
return sysfs_emit(buf, "Not affected\n");
}

+ssize_t __weak cpu_show_retbleed(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ return sysfs_emit(buf, "Not affected\n");
+}
+
static DEVICE_ATTR(meltdown, 0444, cpu_show_meltdown, NULL);
static DEVICE_ATTR(spectre_v1, 0444, cpu_show_spectre_v1, NULL);
static DEVICE_ATTR(spectre_v2, 0444, cpu_show_spectre_v2, NULL);
@@ -584,6 +590,7 @@ static DEVICE_ATTR(tsx_async_abort, 0444, cpu_show_tsx_async_abort, NULL);
static DEVICE_ATTR(itlb_multihit, 0444, cpu_show_itlb_multihit, NULL);
static DEVICE_ATTR(srbds, 0444, cpu_show_srbds, NULL);
static DEVICE_ATTR(mmio_stale_data, 0444, cpu_show_mmio_stale_data, NULL);
+static DEVICE_ATTR(retbleed, 0444, cpu_show_retbleed, NULL);

static struct attribute *cpu_root_vulnerabilities_attrs[] = {
&dev_attr_meltdown.attr,
@@ -596,6 +603,7 @@ static struct attribute *cpu_root_vulnerabilities_attrs[] = {
&dev_attr_itlb_multihit.attr,
&dev_attr_srbds.attr,
&dev_attr_mmio_stale_data.attr,
+ &dev_attr_retbleed.attr,
NULL
};

diff --git a/drivers/cpufreq/acpi-cpufreq.c b/drivers/cpufreq/acpi-cpufreq.c
index 4195834a4591..cf7ebe3bd1ad 100644
--- a/drivers/cpufreq/acpi-cpufreq.c
+++ b/drivers/cpufreq/acpi-cpufreq.c
@@ -30,6 +30,7 @@
#include <asm/msr.h>
#include <asm/processor.h>
#include <asm/cpufeature.h>
+#include <asm/cpu_device_id.h>

MODULE_AUTHOR("Paul Diefenbaugh, Dominik Brodowski");
MODULE_DESCRIPTION("ACPI Processor P-States Driver");
diff --git a/drivers/cpufreq/amd_freq_sensitivity.c b/drivers/cpufreq/amd_freq_sensitivity.c
index e2df9d112106..5107cbe2d64d 100644
--- a/drivers/cpufreq/amd_freq_sensitivity.c
+++ b/drivers/cpufreq/amd_freq_sensitivity.c
@@ -18,6 +18,7 @@

#include <asm/msr.h>
#include <asm/cpufeature.h>
+#include <asm/cpu_device_id.h>

#include "cpufreq_ondemand.h"

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c
index d8687868407d..b588e0e409e7 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c
@@ -35,7 +35,6 @@
#include <linux/pci.h>
#include <linux/pm_runtime.h>
#include <drm/drm_crtc_helper.h>
-#include <drm/drm_damage_helper.h>
#include <drm/drm_edid.h>
#include <drm/drm_gem_framebuffer_helper.h>
#include <drm/drm_fb_helper.h>
@@ -496,7 +495,6 @@ bool amdgpu_display_ddc_probe(struct amdgpu_connector *amdgpu_connector,
static const struct drm_framebuffer_funcs amdgpu_fb_funcs = {
.destroy = drm_gem_fb_destroy,
.create_handle = drm_gem_fb_create_handle,
- .dirty = drm_atomic_helper_dirtyfb,
};

uint32_t amdgpu_display_supported_domains(struct amdgpu_device *adev,
diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c
index 347b08b56042..63b221226261 100644
--- a/drivers/idle/intel_idle.c
+++ b/drivers/idle/intel_idle.c
@@ -46,11 +46,13 @@
#include <linux/tick.h>
#include <trace/events/power.h>
#include <linux/sched.h>
+#include <linux/sched/smt.h>
#include <linux/notifier.h>
#include <linux/cpu.h>
#include <linux/moduleparam.h>
#include <asm/cpu_device_id.h>
#include <asm/intel-family.h>
+#include <asm/nospec-branch.h>
#include <asm/mwait.h>
#include <asm/msr.h>

@@ -97,6 +99,12 @@ static struct cpuidle_state *cpuidle_state_table;
*/
#define CPUIDLE_FLAG_TLB_FLUSHED 0x10000

+/*
+ * Disable IBRS across idle (when KERNEL_IBRS), is exclusive vs IRQ_ENABLE
+ * above.
+ */
+#define CPUIDLE_FLAG_IBRS BIT(16)
+
/*
* MWAIT takes an 8-bit "hint" in EAX "suggesting"
* the C-state (top nibble) and sub-state (bottom nibble)
@@ -107,6 +115,24 @@ static struct cpuidle_state *cpuidle_state_table;
#define flg2MWAIT(flags) (((flags) >> 24) & 0xFF)
#define MWAIT2flg(eax) ((eax & 0xFF) << 24)

+static __cpuidle int intel_idle_ibrs(struct cpuidle_device *dev,
+ struct cpuidle_driver *drv, int index)
+{
+ bool smt_active = sched_smt_active();
+ u64 spec_ctrl = spec_ctrl_current();
+ int ret;
+
+ if (smt_active)
+ wrmsrl(MSR_IA32_SPEC_CTRL, 0);
+
+ ret = intel_idle(dev, drv, index);
+
+ if (smt_active)
+ wrmsrl(MSR_IA32_SPEC_CTRL, spec_ctrl);
+
+ return ret;
+}
+
/*
* States are indexed by the cstate number,
* which is also the index into the MWAIT hint array.
@@ -605,7 +631,7 @@ static struct cpuidle_state skl_cstates[] = {
{
.name = "C6",
.desc = "MWAIT 0x20",
- .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
+ .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED | CPUIDLE_FLAG_IBRS,
.exit_latency = 85,
.target_residency = 200,
.enter = &intel_idle,
@@ -613,7 +639,7 @@ static struct cpuidle_state skl_cstates[] = {
{
.name = "C7s",
.desc = "MWAIT 0x33",
- .flags = MWAIT2flg(0x33) | CPUIDLE_FLAG_TLB_FLUSHED,
+ .flags = MWAIT2flg(0x33) | CPUIDLE_FLAG_TLB_FLUSHED | CPUIDLE_FLAG_IBRS,
.exit_latency = 124,
.target_residency = 800,
.enter = &intel_idle,
@@ -621,7 +647,7 @@ static struct cpuidle_state skl_cstates[] = {
{
.name = "C8",
.desc = "MWAIT 0x40",
- .flags = MWAIT2flg(0x40) | CPUIDLE_FLAG_TLB_FLUSHED,
+ .flags = MWAIT2flg(0x40) | CPUIDLE_FLAG_TLB_FLUSHED | CPUIDLE_FLAG_IBRS,
.exit_latency = 200,
.target_residency = 800,
.enter = &intel_idle,
@@ -629,7 +655,7 @@ static struct cpuidle_state skl_cstates[] = {
{
.name = "C9",
.desc = "MWAIT 0x50",
- .flags = MWAIT2flg(0x50) | CPUIDLE_FLAG_TLB_FLUSHED,
+ .flags = MWAIT2flg(0x50) | CPUIDLE_FLAG_TLB_FLUSHED | CPUIDLE_FLAG_IBRS,
.exit_latency = 480,
.target_residency = 5000,
.enter = &intel_idle,
@@ -637,7 +663,7 @@ static struct cpuidle_state skl_cstates[] = {
{
.name = "C10",
.desc = "MWAIT 0x60",
- .flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED,
+ .flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED | CPUIDLE_FLAG_IBRS,
.exit_latency = 890,
.target_residency = 5000,
.enter = &intel_idle,
@@ -666,7 +692,7 @@ static struct cpuidle_state skx_cstates[] = {
{
.name = "C6",
.desc = "MWAIT 0x20",
- .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
+ .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED | CPUIDLE_FLAG_IBRS,
.exit_latency = 133,
.target_residency = 600,
.enter = &intel_idle,
@@ -1370,6 +1396,11 @@ static void __init intel_idle_cpuidle_driver_init(void)
drv->states[drv->state_count] = /* structure copy */
cpuidle_state_table[cstate];

+ if (cpu_feature_enabled(X86_FEATURE_KERNEL_IBRS) &&
+ cpuidle_state_table[cstate].flags & CPUIDLE_FLAG_IBRS) {
+ drv->states[drv->state_count].enter = intel_idle_ibrs;
+ }
+
drv->state_count += 1;
}

diff --git a/fs/xfs/libxfs/xfs_attr.c b/fs/xfs/libxfs/xfs_attr.c
index 510ca6974604..c83ff610ecb6 100644
--- a/fs/xfs/libxfs/xfs_attr.c
+++ b/fs/xfs/libxfs/xfs_attr.c
@@ -1007,7 +1007,7 @@ xfs_attr_node_addname(
* The INCOMPLETE flag means that we will find the "old"
* attr, not the "new" one.
*/
- args->flags |= XFS_ATTR_INCOMPLETE;
+ args->op_flags |= XFS_DA_OP_INCOMPLETE;
state = xfs_da_state_alloc();
state->args = args;
state->mp = mp;
diff --git a/fs/xfs/libxfs/xfs_attr_leaf.c b/fs/xfs/libxfs/xfs_attr_leaf.c
index 0c23127347ac..c86ddbf6d105 100644
--- a/fs/xfs/libxfs/xfs_attr_leaf.c
+++ b/fs/xfs/libxfs/xfs_attr_leaf.c
@@ -2345,8 +2345,8 @@ xfs_attr3_leaf_lookup_int(
* If we are looking for INCOMPLETE entries, show only those.
* If we are looking for complete entries, show only those.
*/
- if ((args->flags & XFS_ATTR_INCOMPLETE) !=
- (entry->flags & XFS_ATTR_INCOMPLETE)) {
+ if (!!(args->op_flags & XFS_DA_OP_INCOMPLETE) !=
+ !!(entry->flags & XFS_ATTR_INCOMPLETE)) {
continue;
}
if (entry->flags & XFS_ATTR_LOCAL) {
diff --git a/fs/xfs/libxfs/xfs_attr_leaf.h b/fs/xfs/libxfs/xfs_attr_leaf.h
index 7b74e18becff..38c05d6ae2aa 100644
--- a/fs/xfs/libxfs/xfs_attr_leaf.h
+++ b/fs/xfs/libxfs/xfs_attr_leaf.h
@@ -17,13 +17,27 @@ struct xfs_inode;
struct xfs_trans;

/*
- * Used to keep a list of "remote value" extents when unlinking an inode.
+ * Incore version of the attribute leaf header.
*/
-typedef struct xfs_attr_inactive_list {
- xfs_dablk_t valueblk; /* block number of value bytes */
- int valuelen; /* number of bytes in value */
-} xfs_attr_inactive_list_t;
-
+struct xfs_attr3_icleaf_hdr {
+ uint32_t forw;
+ uint32_t back;
+ uint16_t magic;
+ uint16_t count;
+ uint16_t usedbytes;
+ /*
+ * Firstused is 32-bit here instead of 16-bit like the on-disk variant
+ * to support maximum fsb size of 64k without overflow issues throughout
+ * the attr code. Instead, the overflow condition is handled on
+ * conversion to/from disk.
+ */
+ uint32_t firstused;
+ __u8 holes;
+ struct {
+ uint16_t base;
+ uint16_t size;
+ } freemap[XFS_ATTR_LEAF_MAPSIZE];
+};

/*========================================================================
* Function prototypes for the kernel.
diff --git a/fs/xfs/libxfs/xfs_attr_remote.c b/fs/xfs/libxfs/xfs_attr_remote.c
index 3e39b7d40f25..de9096b8a47c 100644
--- a/fs/xfs/libxfs/xfs_attr_remote.c
+++ b/fs/xfs/libxfs/xfs_attr_remote.c
@@ -24,6 +24,23 @@

#define ATTR_RMTVALUE_MAPSIZE 1 /* # of map entries at once */

+/*
+ * Remote Attribute Values
+ * =======================
+ *
+ * Remote extended attribute values are conceptually simple -- they're written
+ * to data blocks mapped by an inode's attribute fork, and they have an upper
+ * size limit of 64k. Setting a value does not involve the XFS log.
+ *
+ * However, on a v5 filesystem, maximally sized remote attr values require one
+ * block more than 64k worth of space to hold both the remote attribute value
+ * header (64 bytes). On a 4k block filesystem this results in a 68k buffer;
+ * on a 64k block filesystem, this would be a 128k buffer. Note that the log
+ * format can only handle a dirty buffer of XFS_MAX_BLOCKSIZE length (64k).
+ * Therefore, we /must/ ensure that remote attribute value buffers never touch
+ * the logging system and therefore never have a log item.
+ */
+
/*
* Each contiguous block has a header, so it is not just a simple attribute
* length to FSB conversion.
@@ -400,17 +417,25 @@ xfs_attr_rmtval_get(
(map[i].br_startblock != HOLESTARTBLOCK));
dblkno = XFS_FSB_TO_DADDR(mp, map[i].br_startblock);
dblkcnt = XFS_FSB_TO_BB(mp, map[i].br_blockcount);
- error = xfs_trans_read_buf(mp, args->trans,
- mp->m_ddev_targp,
- dblkno, dblkcnt, 0, &bp,
- &xfs_attr3_rmt_buf_ops);
- if (error)
+ bp = xfs_buf_read(mp->m_ddev_targp, dblkno, dblkcnt, 0,
+ &xfs_attr3_rmt_buf_ops);
+ if (!bp)
+ return -ENOMEM;
+ error = bp->b_error;
+ if (error) {
+ xfs_buf_ioerror_alert(bp, __func__);
+ xfs_buf_relse(bp);
+
+ /* bad CRC means corrupted metadata */
+ if (error == -EFSBADCRC)
+ error = -EFSCORRUPTED;
return error;
+ }

error = xfs_attr_rmtval_copyout(mp, bp, args->dp->i_ino,
&offset, &valuelen,
&dst);
- xfs_trans_brelse(args->trans, bp);
+ xfs_buf_relse(bp);
if (error)
return error;

@@ -551,6 +576,32 @@ xfs_attr_rmtval_set(
return 0;
}

+/* Mark stale any incore buffers for the remote value. */
+int
+xfs_attr_rmtval_stale(
+ struct xfs_inode *ip,
+ struct xfs_bmbt_irec *map,
+ xfs_buf_flags_t incore_flags)
+{
+ struct xfs_mount *mp = ip->i_mount;
+ struct xfs_buf *bp;
+
+ ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
+
+ ASSERT((map->br_startblock != DELAYSTARTBLOCK) &&
+ (map->br_startblock != HOLESTARTBLOCK));
+
+ bp = xfs_buf_incore(mp->m_ddev_targp,
+ XFS_FSB_TO_DADDR(mp, map->br_startblock),
+ XFS_FSB_TO_BB(mp, map->br_blockcount), incore_flags);
+ if (bp) {
+ xfs_buf_stale(bp);
+ xfs_buf_relse(bp);
+ }
+
+ return 0;
+}
+
/*
* Remove the value associated with an attribute by deleting the
* out-of-line buffer that it is stored on.
@@ -559,7 +610,6 @@ int
xfs_attr_rmtval_remove(
struct xfs_da_args *args)
{
- struct xfs_mount *mp = args->dp->i_mount;
xfs_dablk_t lblkno;
int blkcnt;
int error;
@@ -574,9 +624,6 @@ xfs_attr_rmtval_remove(
blkcnt = args->rmtblkcnt;
while (blkcnt > 0) {
struct xfs_bmbt_irec map;
- struct xfs_buf *bp;
- xfs_daddr_t dblkno;
- int dblkcnt;
int nmap;

/*
@@ -588,21 +635,9 @@ xfs_attr_rmtval_remove(
if (error)
return error;
ASSERT(nmap == 1);
- ASSERT((map.br_startblock != DELAYSTARTBLOCK) &&
- (map.br_startblock != HOLESTARTBLOCK));
-
- dblkno = XFS_FSB_TO_DADDR(mp, map.br_startblock),
- dblkcnt = XFS_FSB_TO_BB(mp, map.br_blockcount);
-
- /*
- * If the "remote" value is in the cache, remove it.
- */
- bp = xfs_buf_incore(mp->m_ddev_targp, dblkno, dblkcnt, XBF_TRYLOCK);
- if (bp) {
- xfs_buf_stale(bp);
- xfs_buf_relse(bp);
- bp = NULL;
- }
+ error = xfs_attr_rmtval_stale(args->dp, &map, XBF_TRYLOCK);
+ if (error)
+ return error;

lblkno += map.br_blockcount;
blkcnt -= map.br_blockcount;
diff --git a/fs/xfs/libxfs/xfs_attr_remote.h b/fs/xfs/libxfs/xfs_attr_remote.h
index 9d20b66ad379..6fb4572845ce 100644
--- a/fs/xfs/libxfs/xfs_attr_remote.h
+++ b/fs/xfs/libxfs/xfs_attr_remote.h
@@ -11,5 +11,7 @@ int xfs_attr3_rmt_blocks(struct xfs_mount *mp, int attrlen);
int xfs_attr_rmtval_get(struct xfs_da_args *args);
int xfs_attr_rmtval_set(struct xfs_da_args *args);
int xfs_attr_rmtval_remove(struct xfs_da_args *args);
+int xfs_attr_rmtval_stale(struct xfs_inode *ip, struct xfs_bmbt_irec *map,
+ xfs_buf_flags_t incore_flags);

#endif /* __XFS_ATTR_REMOTE_H__ */
diff --git a/fs/xfs/libxfs/xfs_da_btree.h b/fs/xfs/libxfs/xfs_da_btree.h
index ae0bbd20d9ca..588e4674e931 100644
--- a/fs/xfs/libxfs/xfs_da_btree.h
+++ b/fs/xfs/libxfs/xfs_da_btree.h
@@ -82,6 +82,7 @@ typedef struct xfs_da_args {
#define XFS_DA_OP_OKNOENT 0x0008 /* lookup/add op, ENOENT ok, else die */
#define XFS_DA_OP_CILOOKUP 0x0010 /* lookup to return CI name if found */
#define XFS_DA_OP_ALLOCVAL 0x0020 /* lookup to alloc buffer if found */
+#define XFS_DA_OP_INCOMPLETE 0x0040 /* lookup INCOMPLETE attr keys */

#define XFS_DA_OP_FLAGS \
{ XFS_DA_OP_JUSTCHECK, "JUSTCHECK" }, \
@@ -89,7 +90,8 @@ typedef struct xfs_da_args {
{ XFS_DA_OP_ADDNAME, "ADDNAME" }, \
{ XFS_DA_OP_OKNOENT, "OKNOENT" }, \
{ XFS_DA_OP_CILOOKUP, "CILOOKUP" }, \
- { XFS_DA_OP_ALLOCVAL, "ALLOCVAL" }
+ { XFS_DA_OP_ALLOCVAL, "ALLOCVAL" }, \
+ { XFS_DA_OP_INCOMPLETE, "INCOMPLETE" }

/*
* Storage for holding state during Btree searches and split/join ops.
@@ -124,6 +126,19 @@ typedef struct xfs_da_state {
/* for dirv2 extrablk is data */
} xfs_da_state_t;

+/*
+ * In-core version of the node header to abstract the differences in the v2 and
+ * v3 disk format of the headers. Callers need to convert to/from disk format as
+ * appropriate.
+ */
+struct xfs_da3_icnode_hdr {
+ uint32_t forw;
+ uint32_t back;
+ uint16_t magic;
+ uint16_t count;
+ uint16_t level;
+};
+
/*
* Utility macros to aid in logging changed structure fields.
*/
diff --git a/fs/xfs/libxfs/xfs_da_format.c b/fs/xfs/libxfs/xfs_da_format.c
index b1ae572496b6..31bb250c1899 100644
--- a/fs/xfs/libxfs/xfs_da_format.c
+++ b/fs/xfs/libxfs/xfs_da_format.c
@@ -13,6 +13,7 @@
#include "xfs_mount.h"
#include "xfs_inode.h"
#include "xfs_dir2.h"
+#include "xfs_dir2_priv.h"

/*
* Shortform directory ops
diff --git a/fs/xfs/libxfs/xfs_da_format.h b/fs/xfs/libxfs/xfs_da_format.h
index ae654e06b2fb..222ee48da5e8 100644
--- a/fs/xfs/libxfs/xfs_da_format.h
+++ b/fs/xfs/libxfs/xfs_da_format.h
@@ -93,19 +93,6 @@ struct xfs_da3_intnode {
struct xfs_da_node_entry __btree[];
};

-/*
- * In-core version of the node header to abstract the differences in the v2 and
- * v3 disk format of the headers. Callers need to convert to/from disk format as
- * appropriate.
- */
-struct xfs_da3_icnode_hdr {
- uint32_t forw;
- uint32_t back;
- uint16_t magic;
- uint16_t count;
- uint16_t level;
-};
-
/*
* Directory version 2.
*
@@ -434,14 +421,6 @@ struct xfs_dir3_leaf_hdr {
__be32 pad; /* 64 bit alignment */
};

-struct xfs_dir3_icleaf_hdr {
- uint32_t forw;
- uint32_t back;
- uint16_t magic;
- uint16_t count;
- uint16_t stale;
-};
-
/*
* Leaf block entry.
*/
@@ -520,19 +499,6 @@ struct xfs_dir3_free {

#define XFS_DIR3_FREE_CRC_OFF offsetof(struct xfs_dir3_free, hdr.hdr.crc)

-/*
- * In core version of the free block header, abstracted away from on-disk format
- * differences. Use this in the code, and convert to/from the disk version using
- * xfs_dir3_free_hdr_from_disk/xfs_dir3_free_hdr_to_disk.
- */
-struct xfs_dir3_icfree_hdr {
- uint32_t magic;
- uint32_t firstdb;
- uint32_t nvalid;
- uint32_t nused;
-
-};
-
/*
* Single block format.
*
@@ -709,29 +675,6 @@ struct xfs_attr3_leafblock {
*/
};

-/*
- * incore, neutral version of the attribute leaf header
- */
-struct xfs_attr3_icleaf_hdr {
- uint32_t forw;
- uint32_t back;
- uint16_t magic;
- uint16_t count;
- uint16_t usedbytes;
- /*
- * firstused is 32-bit here instead of 16-bit like the on-disk variant
- * to support maximum fsb size of 64k without overflow issues throughout
- * the attr code. Instead, the overflow condition is handled on
- * conversion to/from disk.
- */
- uint32_t firstused;
- __u8 holes;
- struct {
- uint16_t base;
- uint16_t size;
- } freemap[XFS_ATTR_LEAF_MAPSIZE];
-};
-
/*
* Special value to represent fs block size in the leaf header firstused field.
* Only used when block size overflows the 2-bytes available on disk.
@@ -740,8 +683,6 @@ struct xfs_attr3_icleaf_hdr {

/*
* Flags used in the leaf_entry[i].flags field.
- * NOTE: the INCOMPLETE bit must not collide with the flags bits specified
- * on the system call, they are "or"ed together for various operations.
*/
#define XFS_ATTR_LOCAL_BIT 0 /* attr is stored locally */
#define XFS_ATTR_ROOT_BIT 1 /* limit access to trusted attrs */
diff --git a/fs/xfs/libxfs/xfs_dir2.h b/fs/xfs/libxfs/xfs_dir2.h
index f54244779492..e170792c0acc 100644
--- a/fs/xfs/libxfs/xfs_dir2.h
+++ b/fs/xfs/libxfs/xfs_dir2.h
@@ -18,6 +18,8 @@ struct xfs_dir2_sf_entry;
struct xfs_dir2_data_hdr;
struct xfs_dir2_data_entry;
struct xfs_dir2_data_unused;
+struct xfs_dir3_icfree_hdr;
+struct xfs_dir3_icleaf_hdr;

extern struct xfs_name xfs_name_dotdot;

diff --git a/fs/xfs/libxfs/xfs_dir2_priv.h b/fs/xfs/libxfs/xfs_dir2_priv.h
index 59f9fb2241a5..d2eaea663e7f 100644
--- a/fs/xfs/libxfs/xfs_dir2_priv.h
+++ b/fs/xfs/libxfs/xfs_dir2_priv.h
@@ -8,6 +8,25 @@

struct dir_context;

+/*
+ * In-core version of the leaf and free block headers to abstract the
+ * differences in the v2 and v3 disk format of the headers.
+ */
+struct xfs_dir3_icleaf_hdr {
+ uint32_t forw;
+ uint32_t back;
+ uint16_t magic;
+ uint16_t count;
+ uint16_t stale;
+};
+
+struct xfs_dir3_icfree_hdr {
+ uint32_t magic;
+ uint32_t firstdb;
+ uint32_t nvalid;
+ uint32_t nused;
+};
+
/* xfs_dir2.c */
extern int xfs_dir2_grow_inode(struct xfs_da_args *args, int space,
xfs_dir2_db_t *dbp);
diff --git a/fs/xfs/libxfs/xfs_format.h b/fs/xfs/libxfs/xfs_format.h
index c968b60cee15..28203b626f6a 100644
--- a/fs/xfs/libxfs/xfs_format.h
+++ b/fs/xfs/libxfs/xfs_format.h
@@ -1540,6 +1540,13 @@ typedef struct xfs_bmdr_block {
#define BMBT_BLOCKCOUNT_BITLEN 21

#define BMBT_STARTOFF_MASK ((1ULL << BMBT_STARTOFF_BITLEN) - 1)
+#define BMBT_BLOCKCOUNT_MASK ((1ULL << BMBT_BLOCKCOUNT_BITLEN) - 1)
+
+/*
+ * bmbt records have a file offset (block) field that is 54 bits wide, so this
+ * is the largest xfs_fileoff_t that we ever expect to see.
+ */
+#define XFS_MAX_FILEOFF (BMBT_STARTOFF_MASK + BMBT_BLOCKCOUNT_MASK)

typedef struct xfs_bmbt_rec {
__be64 l0, l1;
diff --git a/fs/xfs/xfs_attr_inactive.c b/fs/xfs/xfs_attr_inactive.c
index 766b1386402a..9c88203b537b 100644
--- a/fs/xfs/xfs_attr_inactive.c
+++ b/fs/xfs/xfs_attr_inactive.c
@@ -25,22 +25,18 @@
#include "xfs_error.h"

/*
- * Look at all the extents for this logical region,
- * invalidate any buffers that are incore/in transactions.
+ * Invalidate any incore buffers associated with this remote attribute value
+ * extent. We never log remote attribute value buffers, which means that they
+ * won't be attached to a transaction and are therefore safe to mark stale.
+ * The actual bunmapi will be taken care of later.
*/
STATIC int
-xfs_attr3_leaf_freextent(
- struct xfs_trans **trans,
+xfs_attr3_rmt_stale(
struct xfs_inode *dp,
xfs_dablk_t blkno,
int blkcnt)
{
struct xfs_bmbt_irec map;
- struct xfs_buf *bp;
- xfs_dablk_t tblkno;
- xfs_daddr_t dblkno;
- int tblkcnt;
- int dblkcnt;
int nmap;
int error;

@@ -48,47 +44,28 @@ xfs_attr3_leaf_freextent(
* Roll through the "value", invalidating the attribute value's
* blocks.
*/
- tblkno = blkno;
- tblkcnt = blkcnt;
- while (tblkcnt > 0) {
+ while (blkcnt > 0) {
/*
* Try to remember where we decided to put the value.
*/
nmap = 1;
- error = xfs_bmapi_read(dp, (xfs_fileoff_t)tblkno, tblkcnt,
+ error = xfs_bmapi_read(dp, (xfs_fileoff_t)blkno, blkcnt,
&map, &nmap, XFS_BMAPI_ATTRFORK);
- if (error) {
+ if (error)
return error;
- }
ASSERT(nmap == 1);
- ASSERT(map.br_startblock != DELAYSTARTBLOCK);

/*
- * If it's a hole, these are already unmapped
- * so there's nothing to invalidate.
+ * Mark any incore buffers for the remote value as stale. We
+ * never log remote attr value buffers, so the buffer should be
+ * easy to kill.
*/
- if (map.br_startblock != HOLESTARTBLOCK) {
-
- dblkno = XFS_FSB_TO_DADDR(dp->i_mount,
- map.br_startblock);
- dblkcnt = XFS_FSB_TO_BB(dp->i_mount,
- map.br_blockcount);
- bp = xfs_trans_get_buf(*trans,
- dp->i_mount->m_ddev_targp,
- dblkno, dblkcnt, 0);
- if (!bp)
- return -ENOMEM;
- xfs_trans_binval(*trans, bp);
- /*
- * Roll to next transaction.
- */
- error = xfs_trans_roll_inode(trans, dp);
- if (error)
- return error;
- }
+ error = xfs_attr_rmtval_stale(dp, &map, 0);
+ if (error)
+ return error;

- tblkno += map.br_blockcount;
- tblkcnt -= map.br_blockcount;
+ blkno += map.br_blockcount;
+ blkcnt -= map.br_blockcount;
}

return 0;
@@ -102,86 +79,45 @@ xfs_attr3_leaf_freextent(
*/
STATIC int
xfs_attr3_leaf_inactive(
- struct xfs_trans **trans,
- struct xfs_inode *dp,
- struct xfs_buf *bp)
+ struct xfs_trans **trans,
+ struct xfs_inode *dp,
+ struct xfs_buf *bp)
{
- struct xfs_attr_leafblock *leaf;
- struct xfs_attr3_icleaf_hdr ichdr;
- struct xfs_attr_leaf_entry *entry;
+ struct xfs_attr3_icleaf_hdr ichdr;
+ struct xfs_mount *mp = bp->b_mount;
+ struct xfs_attr_leafblock *leaf = bp->b_addr;
+ struct xfs_attr_leaf_entry *entry;
struct xfs_attr_leaf_name_remote *name_rmt;
- struct xfs_attr_inactive_list *list;
- struct xfs_attr_inactive_list *lp;
- int error;
- int count;
- int size;
- int tmp;
- int i;
- struct xfs_mount *mp = bp->b_mount;
+ int error = 0;
+ int i;

- leaf = bp->b_addr;
xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &ichdr, leaf);

/*
- * Count the number of "remote" value extents.
+ * Find the remote value extents for this leaf and invalidate their
+ * incore buffers.
*/
- count = 0;
entry = xfs_attr3_leaf_entryp(leaf);
for (i = 0; i < ichdr.count; entry++, i++) {
- if (be16_to_cpu(entry->nameidx) &&
- ((entry->flags & XFS_ATTR_LOCAL) == 0)) {
- name_rmt = xfs_attr3_leaf_name_remote(leaf, i);
- if (name_rmt->valueblk)
- count++;
- }
- }
-
- /*
- * If there are no "remote" values, we're done.
- */
- if (count == 0) {
- xfs_trans_brelse(*trans, bp);
- return 0;
- }
+ int blkcnt;

- /*
- * Allocate storage for a list of all the "remote" value extents.
- */
- size = count * sizeof(xfs_attr_inactive_list_t);
- list = kmem_alloc(size, 0);
-
- /*
- * Identify each of the "remote" value extents.
- */
- lp = list;
- entry = xfs_attr3_leaf_entryp(leaf);
- for (i = 0; i < ichdr.count; entry++, i++) {
- if (be16_to_cpu(entry->nameidx) &&
- ((entry->flags & XFS_ATTR_LOCAL) == 0)) {
- name_rmt = xfs_attr3_leaf_name_remote(leaf, i);
- if (name_rmt->valueblk) {
- lp->valueblk = be32_to_cpu(name_rmt->valueblk);
- lp->valuelen = xfs_attr3_rmt_blocks(dp->i_mount,
- be32_to_cpu(name_rmt->valuelen));
- lp++;
- }
- }
- }
- xfs_trans_brelse(*trans, bp); /* unlock for trans. in freextent() */
+ if (!entry->nameidx || (entry->flags & XFS_ATTR_LOCAL))
+ continue;

- /*
- * Invalidate each of the "remote" value extents.
- */
- error = 0;
- for (lp = list, i = 0; i < count; i++, lp++) {
- tmp = xfs_attr3_leaf_freextent(trans, dp,
- lp->valueblk, lp->valuelen);
+ name_rmt = xfs_attr3_leaf_name_remote(leaf, i);
+ if (!name_rmt->valueblk)
+ continue;

- if (error == 0)
- error = tmp; /* save only the 1st errno */
+ blkcnt = xfs_attr3_rmt_blocks(dp->i_mount,
+ be32_to_cpu(name_rmt->valuelen));
+ error = xfs_attr3_rmt_stale(dp,
+ be32_to_cpu(name_rmt->valueblk), blkcnt);
+ if (error)
+ goto err;
}

- kmem_free(list);
+ xfs_trans_brelse(*trans, bp);
+err:
return error;
}

diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
index 203065a64765..e41c13ffa5a4 100644
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -187,7 +187,12 @@ xfs_file_dio_aio_read(

file_accessed(iocb->ki_filp);

- xfs_ilock(ip, XFS_IOLOCK_SHARED);
+ if (iocb->ki_flags & IOCB_NOWAIT) {
+ if (!xfs_ilock_nowait(ip, XFS_IOLOCK_SHARED))
+ return -EAGAIN;
+ } else {
+ xfs_ilock(ip, XFS_IOLOCK_SHARED);
+ }
ret = iomap_dio_rw(iocb, to, &xfs_iomap_ops, NULL);
xfs_iunlock(ip, XFS_IOLOCK_SHARED);

diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c
index 7b72c189cff0..30202d8c25e4 100644
--- a/fs/xfs/xfs_inode.c
+++ b/fs/xfs/xfs_inode.c
@@ -1513,10 +1513,8 @@ xfs_itruncate_extents_flags(
struct xfs_mount *mp = ip->i_mount;
struct xfs_trans *tp = *tpp;
xfs_fileoff_t first_unmap_block;
- xfs_fileoff_t last_block;
xfs_filblks_t unmap_len;
int error = 0;
- int done = 0;

ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
ASSERT(!atomic_read(&VFS_I(ip)->i_count) ||
@@ -1536,21 +1534,22 @@ xfs_itruncate_extents_flags(
* the end of the file (in a crash where the space is allocated
* but the inode size is not yet updated), simply remove any
* blocks which show up between the new EOF and the maximum
- * possible file size. If the first block to be removed is
- * beyond the maximum file size (ie it is the same as last_block),
- * then there is nothing to do.
+ * possible file size.
+ *
+ * We have to free all the blocks to the bmbt maximum offset, even if
+ * the page cache can't scale that far.
*/
first_unmap_block = XFS_B_TO_FSB(mp, (xfs_ufsize_t)new_size);
- last_block = XFS_B_TO_FSB(mp, mp->m_super->s_maxbytes);
- if (first_unmap_block == last_block)
+ if (first_unmap_block >= XFS_MAX_FILEOFF) {
+ WARN_ON_ONCE(first_unmap_block > XFS_MAX_FILEOFF);
return 0;
+ }

- ASSERT(first_unmap_block < last_block);
- unmap_len = last_block - first_unmap_block + 1;
- while (!done) {
+ unmap_len = XFS_MAX_FILEOFF - first_unmap_block + 1;
+ while (unmap_len > 0) {
ASSERT(tp->t_firstblock == NULLFSBLOCK);
- error = xfs_bunmapi(tp, ip, first_unmap_block, unmap_len, flags,
- XFS_ITRUNC_MAX_EXTENTS, &done);
+ error = __xfs_bunmapi(tp, ip, first_unmap_block, &unmap_len,
+ flags, XFS_ITRUNC_MAX_EXTENTS);
if (error)
goto out;

@@ -1570,7 +1569,7 @@ xfs_itruncate_extents_flags(
if (whichfork == XFS_DATA_FORK) {
/* Remove all pending CoW reservations. */
error = xfs_reflink_cancel_cow_blocks(ip, &tp,
- first_unmap_block, last_block, true);
+ first_unmap_block, XFS_MAX_FILEOFF, true);
if (error)
goto out;

diff --git a/fs/xfs/xfs_reflink.c b/fs/xfs/xfs_reflink.c
index 904d8285c226..dfbf3f8f1ec8 100644
--- a/fs/xfs/xfs_reflink.c
+++ b/fs/xfs/xfs_reflink.c
@@ -1544,7 +1544,8 @@ xfs_reflink_clear_inode_flag(
* We didn't find any shared blocks so turn off the reflink flag.
* First, get rid of any leftover CoW mappings.
*/
- error = xfs_reflink_cancel_cow_blocks(ip, tpp, 0, NULLFILEOFF, true);
+ error = xfs_reflink_cancel_cow_blocks(ip, tpp, 0, XFS_MAX_FILEOFF,
+ true);
if (error)
return error;

diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
index 8d1df9f8be07..a3a54a0fbffe 100644
--- a/fs/xfs/xfs_super.c
+++ b/fs/xfs/xfs_super.c
@@ -512,32 +512,6 @@ xfs_showargs(
seq_puts(m, ",noquota");
}

-static uint64_t
-xfs_max_file_offset(
- unsigned int blockshift)
-{
- unsigned int pagefactor = 1;
- unsigned int bitshift = BITS_PER_LONG - 1;
-
- /* Figure out maximum filesize, on Linux this can depend on
- * the filesystem blocksize (on 32 bit platforms).
- * __block_write_begin does this in an [unsigned] long long...
- * page->index << (PAGE_SHIFT - bbits)
- * So, for page sized blocks (4K on 32 bit platforms),
- * this wraps at around 8Tb (hence MAX_LFS_FILESIZE which is
- * (((u64)PAGE_SIZE << (BITS_PER_LONG-1))-1)
- * but for smaller blocksizes it is less (bbits = log2 bsize).
- */
-
-#if BITS_PER_LONG == 32
- ASSERT(sizeof(sector_t) == 8);
- pagefactor = PAGE_SIZE;
- bitshift = BITS_PER_LONG;
-#endif
-
- return (((uint64_t)pagefactor) << bitshift) - 1;
-}
-
/*
* Set parameters for inode allocation heuristics, taking into account
* filesystem size and inode32/inode64 mount options; i.e. specifically
@@ -1650,6 +1624,26 @@ xfs_fs_fill_super(
if (error)
goto out_free_sb;

+ /*
+ * XFS block mappings use 54 bits to store the logical block offset.
+ * This should suffice to handle the maximum file size that the VFS
+ * supports (currently 2^63 bytes on 64-bit and ULONG_MAX << PAGE_SHIFT
+ * bytes on 32-bit), but as XFS and VFS have gotten the s_maxbytes
+ * calculation wrong on 32-bit kernels in the past, we'll add a WARN_ON
+ * to check this assertion.
+ *
+ * Avoid integer overflow by comparing the maximum bmbt offset to the
+ * maximum pagecache offset in units of fs blocks.
+ */
+ if (XFS_B_TO_FSBT(mp, MAX_LFS_FILESIZE) > XFS_MAX_FILEOFF) {
+ xfs_warn(mp,
+"MAX_LFS_FILESIZE block offset (%llu) exceeds extent map maximum (%llu)!",
+ XFS_B_TO_FSBT(mp, MAX_LFS_FILESIZE),
+ XFS_MAX_FILEOFF);
+ error = -EINVAL;
+ goto out_free_sb;
+ }
+
error = xfs_filestream_mount(mp);
if (error)
goto out_free_sb;
@@ -1661,7 +1655,7 @@ xfs_fs_fill_super(
sb->s_magic = XFS_SUPER_MAGIC;
sb->s_blocksize = mp->m_sb.sb_blocksize;
sb->s_blocksize_bits = ffs(sb->s_blocksize) - 1;
- sb->s_maxbytes = xfs_max_file_offset(sb->s_blocksize_bits);
+ sb->s_maxbytes = MAX_LFS_FILESIZE;
sb->s_max_links = XFS_MAXLINK;
sb->s_time_gran = 1;
sb->s_time_min = S32_MIN;
diff --git a/include/linux/cpu.h b/include/linux/cpu.h
index 29a6fa2f518d..b42e9c413447 100644
--- a/include/linux/cpu.h
+++ b/include/linux/cpu.h
@@ -68,6 +68,8 @@ extern ssize_t cpu_show_srbds(struct device *dev, struct device_attribute *attr,
extern ssize_t cpu_show_mmio_stale_data(struct device *dev,
struct device_attribute *attr,
char *buf);
+extern ssize_t cpu_show_retbleed(struct device *dev,
+ struct device_attribute *attr, char *buf);

extern __printf(4, 5)
struct device *cpu_device_create(struct device *parent, void *drvdata,
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index dd4cdad76b18..ee7d57478a45 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -955,7 +955,7 @@ static inline void kvm_arch_end_assignment(struct kvm *kvm)
{
}

-static inline bool kvm_arch_has_assigned_device(struct kvm *kvm)
+static __always_inline bool kvm_arch_has_assigned_device(struct kvm *kvm)
{
return false;
}
diff --git a/include/linux/mod_devicetable.h b/include/linux/mod_devicetable.h
index 4c56404e53a7..8265b99d6d55 100644
--- a/include/linux/mod_devicetable.h
+++ b/include/linux/mod_devicetable.h
@@ -672,9 +672,7 @@ struct x86_cpu_id {
__u16 steppings;
};

-#define X86_FEATURE_MATCH(x) \
- { X86_VENDOR_ANY, X86_FAMILY_ANY, X86_MODEL_ANY, x }
-
+/* Wild cards for x86_cpu_id::vendor, family, model and feature */
#define X86_VENDOR_ANY 0xffff
#define X86_FAMILY_ANY 0
#define X86_MODEL_ANY 0
diff --git a/scripts/Makefile.extrawarn b/scripts/Makefile.extrawarn
index 854e2ba9daa2..6a78afc6f13b 100644
--- a/scripts/Makefile.extrawarn
+++ b/scripts/Makefile.extrawarn
@@ -50,6 +50,7 @@ KBUILD_CFLAGS += -Wno-sign-compare
KBUILD_CFLAGS += -Wno-format-zero-length
KBUILD_CFLAGS += $(call cc-disable-warning, pointer-to-enum-cast)
KBUILD_CFLAGS += $(call cc-disable-warning, unaligned-access)
+KBUILD_CFLAGS += $(call cc-disable-warning, cast-function-type-strict)
endif

endif
diff --git a/tools/arch/x86/include/asm/cpufeatures.h b/tools/arch/x86/include/asm/cpufeatures.h
index 59f924e92c28..3efaf338d325 100644
--- a/tools/arch/x86/include/asm/cpufeatures.h
+++ b/tools/arch/x86/include/asm/cpufeatures.h
@@ -284,7 +284,7 @@
#define X86_FEATURE_CQM_MBM_LOCAL (11*32+ 3) /* LLC Local MBM monitoring */
#define X86_FEATURE_FENCE_SWAPGS_USER (11*32+ 4) /* "" LFENCE in user entry SWAPGS path */
#define X86_FEATURE_FENCE_SWAPGS_KERNEL (11*32+ 5) /* "" LFENCE in kernel entry SWAPGS path */
-#define X86_FEATURE_RSB_VMEXIT_LITE (11*32+ 6) /* "" Fill RSB on VM-Exit when EIBRS is enabled */
+#define X86_FEATURE_RSB_VMEXIT_LITE (11*32+17) /* "" Fill RSB on VM-Exit when EIBRS is enabled */

/* Intel-defined CPU features, CPUID level 0x00000007:1 (EAX), word 12 */
#define X86_FEATURE_AVX512_BF16 (12*32+ 5) /* AVX512 BFLOAT16 instructions */