[PATCH 17/23] x86, realmode: fix 64-bit wakeup sequence
From: Jarkko Sakkinen
Date: Tue May 08 2012 - 14:24:59 EST
There were number of issues in wakeup sequence:
- Wakeup stack was placed in hardcoded address.
- NX bit in EFER was not enabled.
- Initialization incorrectly set physical address
of secondary_startup_64.
- Some alignment issues.
This patch fixes these issues and in addition:
- Unifies coding conventions in .S files.
- Sets alignments of code and data right.
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxx>
Originally-by: H. Peter Anvin <hpa@xxxxxxxxxxxxxxx>
---
arch/x86/kernel/realmode.c | 2 +-
arch/x86/realmode/rm/Makefile | 1 +
arch/x86/realmode/rm/header.S | 2 +-
arch/x86/realmode/rm/reboot_32.S | 18 +++----
arch/x86/realmode/rm/stack.S | 19 ++++++++
arch/x86/realmode/rm/trampoline_32.S | 29 ++++++------
arch/x86/realmode/rm/trampoline_64.S | 67 +++++++++++---------------
arch/x86/realmode/rm/wakeup/wakeup_asm.S | 75 ++++++++++++++----------------
arch/x86/realmode/rmpiggy.S | 4 +-
9 files changed, 110 insertions(+), 107 deletions(-)
create mode 100644 arch/x86/realmode/rm/stack.S
diff --git a/arch/x86/kernel/realmode.c b/arch/x86/kernel/realmode.c
index d85ac20..e7bf82a 100644
--- a/arch/x86/kernel/realmode.c
+++ b/arch/x86/kernel/realmode.c
@@ -64,7 +64,7 @@ void __init setup_real_mode(void)
*((u32 *)__va(real_mode_header.boot_gdt)) = __pa(boot_gdt);
#else
*((u64 *) __va(real_mode_header.startup_64_smp)) =
- (u64) __pa(secondary_startup_64);
+ (u64)secondary_startup_64;
*((u64 *) __va(real_mode_header.level3_ident_pgt)) =
__pa(level3_ident_pgt) + _KERNPG_TABLE;
diff --git a/arch/x86/realmode/rm/Makefile b/arch/x86/realmode/rm/Makefile
index 2423142..c2c27a4 100644
--- a/arch/x86/realmode/rm/Makefile
+++ b/arch/x86/realmode/rm/Makefile
@@ -13,6 +13,7 @@ always := realmode.bin
realmode-y += header.o
realmode-y += trampoline_$(BITS).o
+realmode-y += stack.o
realmode-$(CONFIG_X86_32) += reboot_32.o
realmode-$(CONFIG_ACPI_SLEEP) += wakeup/wakeup.o
diff --git a/arch/x86/realmode/rm/header.S b/arch/x86/realmode/rm/header.S
index 730b131..a91ec8f 100644
--- a/arch/x86/realmode/rm/header.S
+++ b/arch/x86/realmode/rm/header.S
@@ -9,7 +9,7 @@
.section ".header", "a"
-ENTRY(real_mode_header)
+GLOBAL(real_mode_header)
.long pa_text_start
.long pa_ro_end
.long pa_end
diff --git a/arch/x86/realmode/rm/reboot_32.S b/arch/x86/realmode/rm/reboot_32.S
index 50ba994..8d9bfd1 100644
--- a/arch/x86/realmode/rm/reboot_32.S
+++ b/arch/x86/realmode/rm/reboot_32.S
@@ -16,10 +16,9 @@
*/
.section ".text32", "ax"
.code32
- .globl machine_real_restart_asm
- .balign 16
-machine_real_restart_asm:
+ .balign 16
+ENTRY(machine_real_restart_asm)
/* Set up the IDT for real mode. */
lidtl pa_machine_real_restart_idt
@@ -67,7 +66,7 @@ machine_real_restart_asm:
.text
.code16
- .balign 16
+ .balign 16
machine_real_restart_asm16:
1:
xorl %ecx, %ecx
@@ -102,15 +101,15 @@ bios:
ljmpw $0xf000, $0xfff0
.section ".rodata", "a"
- .globl machine_real_restart_idt, machine_real_restart_gdt
- .balign 16
-machine_real_restart_idt:
+ .balign 16
+GLOBAL(machine_real_restart_idt)
.word 0xffff /* Length - real mode default value */
.long 0 /* Base - real mode default value */
+END(machine_real_restart_idt)
- .balign 16
-machine_real_restart_gdt:
+ .balign 16
+GLOBAL(machine_real_restart_gdt)
/* Self-pointer */
.word 0xffff /* Length - real mode default value */
.long pa_machine_real_restart_gdt
@@ -130,3 +129,4 @@ machine_real_restart_gdt:
* semantics we don't have to reload the segments once CR0.PE = 0.
*/
.quad GDT_ENTRY(0x0093, 0x100, 0xffff)
+END(machine_real_restart_gdt)
diff --git a/arch/x86/realmode/rm/stack.S b/arch/x86/realmode/rm/stack.S
new file mode 100644
index 0000000..867ae87
--- /dev/null
+++ b/arch/x86/realmode/rm/stack.S
@@ -0,0 +1,19 @@
+/*
+ * Common heap and stack allocations
+ */
+
+#include <linux/linkage.h>
+
+ .data
+GLOBAL(HEAP)
+ .long rm_heap
+GLOBAL(heap_end)
+ .long rm_stack
+
+ .bss
+ .balign 16
+GLOBAL(rm_heap)
+ .space 2048
+GLOBAL(rm_stack)
+ .space 2048
+GLOBAL(rm_stack_end)
diff --git a/arch/x86/realmode/rm/trampoline_32.S b/arch/x86/realmode/rm/trampoline_32.S
index 279f82e..1ecdbb5 100644
--- a/arch/x86/realmode/rm/trampoline_32.S
+++ b/arch/x86/realmode/rm/trampoline_32.S
@@ -33,10 +33,9 @@
.text
.code16
- .globl trampoline_data
- .balign PAGE_SIZE
-trampoline_data:
+ .balign PAGE_SIZE
+ENTRY(trampoline_data)
wbinvd # Needed for NUMA-Q should be harmless for others
LJMPW_RM(1f)
@@ -70,20 +69,22 @@ trampoline_data:
ENTRY(startup_32) # note: also used from wakeup_asm.S
jmp *%eax
- .data
- .globl startup_32_smp, boot_gdt, trampoline_status
- .balign 4
-boot_gdt_descr:
- .word __BOOT_DS + 7 # gdt limit
-boot_gdt:
- .long 0 # gdt base
+ .section ".rodata","a"
+ .balign 4
boot_idt_descr:
.word 0 # idt limit = 0
.long 0 # idt base = 0L
-trampoline_status:
- .long 0
+ .data
-startup_32_smp:
- .long 0
+boot_gdt_descr:
+ .word __BOOT_DS + 7 # gdt limit
+GLOBAL(boot_gdt)
+ .long 0 # gdt base
+
+ .bss
+
+ .balign 4
+GLOBAL(trampoline_status) .space 4
+GLOBAL(startup_32_smp) .space 4
diff --git a/arch/x86/realmode/rm/trampoline_64.S b/arch/x86/realmode/rm/trampoline_64.S
index 7459c52..195a307 100644
--- a/arch/x86/realmode/rm/trampoline_64.S
+++ b/arch/x86/realmode/rm/trampoline_64.S
@@ -52,7 +52,7 @@ ENTRY(trampoline_data)
# write marker for master knows we're running
# Setup stack
- movw $trampoline_stack_end, %sp
+ movl $rm_stack_end, %esp
call verify_cpu # Verify the cpu supports long mode
testl %eax, %eax # Check for return code
@@ -68,8 +68,11 @@ ENTRY(trampoline_data)
lidtl tidt # load idt with 0, 0
lgdtl tgdt # load gdt with whatever is appropriate
- mov $X86_CR0_PE, %ax # protected mode (PE) bit
- lmsw %ax # into protected mode
+ movw $__KERNEL_DS, %dx # Data segment descriptor
+
+ # Enable protected mode
+ movl $X86_CR0_PE, %eax # protected mode (PE) bit
+ movl %eax, %cr0 # into protected mode
# flush prefetch and jump to startup_32
ljmpl $__KERNEL32_CS, $pa_startup_32
@@ -83,27 +86,27 @@ no_longmode:
.code32
.balign 4
ENTRY(startup_32)
- movl $__KERNEL_DS, %eax # Initialize the %ds segment register
- movl %eax, %ds
+ movl %edx, %ss
+ addl $pa_real_mode_base, %esp
+ movl %edx, %ds
+ movl %edx, %es
+ movl %edx, %fs
+ movl %edx, %gs
movl $X86_CR4_PAE, %eax
movl %eax, %cr4 # Enable PAE mode
- movl pa_startup_64_smp, %esi
- movl pa_startup_64_smp_high, %edi
-
- # Setup trampoline 4 level pagetables
- leal pa_trampoline_level4_pgt, %eax
+ # Setup trampoline 4 level pagetables
+ movl $pa_level3_ident_pgt, %eax
movl %eax, %cr3
movl $MSR_EFER, %ecx
- movl $(1 << _EFER_LME), %eax # Enable Long Mode
+ movl $((1 << _EFER_LME) | (1 << _EFER_NX)), %eax # Enable Long Mode
xorl %edx, %edx
wrmsr
# Enable paging and in turn activate Long Mode
- # Enable protected mode
- movl $(X86_CR0_PG | X86_CR0_PE), %eax
+ movl $(X86_CR0_PG | X86_CR0_WP | X86_CR0_PE), %eax
movl %eax, %cr0
/*
@@ -119,10 +122,7 @@ ENTRY(startup_32)
.balign 4
ENTRY(startup_64)
# Now jump into the kernel using virtual addresses
- movl %edi, %eax
- shlq $32, %rax
- addl %esi, %eax
- jmp *%rax
+ jmpq *startup_64_smp(%rip)
.section ".rodata","a"
.balign 16
@@ -132,10 +132,10 @@ tidt:
# Duplicate the global descriptor table
# so the kernel can live anywhere
- .balign 4
+ .balign 16
.globl tgdt
tgdt:
- .short tgdt_end - tgdt # gdt limit
+ .short tgdt_end - tgdt - 1 # gdt limit
.long pa_tgdt
.short 0
.quad 0x00cf9b000000ffff # __KERNEL32_CS
@@ -143,23 +143,12 @@ tgdt:
.quad 0x00cf93000000ffff # __KERNEL_DS
tgdt_end:
- .data
- .balign 4
-GLOBAL(trampoline_status)
- .long 0
-
-trampoline_stack:
- .org 0x1000
-trampoline_stack_end:
-
- .globl level3_ident_pgt
- .globl level3_kernel_pgt
-GLOBAL(trampoline_level4_pgt)
- level3_ident_pgt: .quad 0
- .fill 510,8,0
- level3_kernel_pgt: .quad 0
-
- .globl startup_64_smp
- .globl startup_64_smp_high
-startup_64_smp: .long 0
-startup_64_smp_high: .long 0
+ .bss
+
+ .balign PAGE_SIZE
+GLOBAL(level3_ident_pgt) .space 511*8
+GLOBAL(level3_kernel_pgt) .space 8
+
+ .balign 8
+GLOBAL(startup_64_smp) .space 8
+GLOBAL(trampoline_status) .space 4
diff --git a/arch/x86/realmode/rm/wakeup/wakeup_asm.S b/arch/x86/realmode/rm/wakeup/wakeup_asm.S
index 8064e1c..f81c1cd 100644
--- a/arch/x86/realmode/rm/wakeup/wakeup_asm.S
+++ b/arch/x86/realmode/rm/wakeup/wakeup_asm.S
@@ -1,6 +1,7 @@
/*
* ACPI wakeup real mode startup stub
*/
+#include <linux/linkage.h>
#include <asm/segment.h>
#include <asm/msr-index.h>
#include <asm/page_types.h>
@@ -9,31 +10,33 @@
#include "../realmode.h"
#include "wakeup.h"
- .code16
+ .code16
/* This should match the structure in wakeup.h */
- .section ".data", "aw"
- .globl wakeup_header
-wakeup_header:
-video_mode: .short 0 /* Video mode number */
-pmode_entry: .long 0
-pmode_cs: .short __KERNEL_CS
-pmode_cr0: .long 0 /* Saved %cr0 */
-pmode_cr3: .long 0 /* Saved %cr3 */
-pmode_cr4: .long 0 /* Saved %cr4 */
-pmode_efer: .quad 0 /* Saved EFER */
-pmode_gdt: .quad 0
-pmode_misc_en: .quad 0 /* Saved MISC_ENABLE MSR */
-pmode_behavior: .long 0 /* Wakeup behavior flags */
-realmode_flags: .long 0
-real_magic: .long 0
-signature: .long WAKEUP_HEADER_SIGNATURE
- .size wakeup_header, .-wakeup_header
+ .section ".data", "aw"
+
+ .balign 16
+GLOBAL(wakeup_header)
+ video_mode: .short 0 /* Video mode number */
+ pmode_entry: .long 0
+ pmode_cs: .short __KERNEL_CS
+ pmode_cr0: .long 0 /* Saved %cr0 */
+ pmode_cr3: .long 0 /* Saved %cr3 */
+ pmode_cr4: .long 0 /* Saved %cr4 */
+ pmode_efer: .quad 0 /* Saved EFER */
+ pmode_gdt: .quad 0
+ pmode_misc_en: .quad 0 /* Saved MISC_ENABLE MSR */
+ pmode_behavior: .long 0 /* Wakeup behavior flags */
+ realmode_flags: .long 0
+ real_magic: .long 0
+ signature: .long WAKEUP_HEADER_SIGNATURE
+END(wakeup_header)
.text
.code16
- .globl wakeup_start
-wakeup_start:
+
+ .balign 16
+ENTRY(wakeup_start)
cli
cld
@@ -62,12 +65,14 @@ wakeup_start:
3:
/* Set up segments */
movw %cs, %ax
+ movw %ax, %ss
+ movl $rm_stack_end, %esp
movw %ax, %ds
movw %ax, %es
- movw %ax, %ss
- lidtl wakeup_idt
+ movw %ax, %fs
+ movw %ax, %gs
- movl $wakeup_stack_end, %esp
+ lidtl wakeup_idt
/* Clear the EFLAGS */
pushl $0
@@ -145,9 +150,8 @@ bogus_real_magic:
* be the case for other laptops or integrated video devices.
*/
- .globl wakeup_gdt
.balign 16
-wakeup_gdt:
+GLOBAL(wakeup_gdt)
.word 3*8-1 /* Self-descriptor */
.long pa_wakeup_gdt
.word 0
@@ -159,29 +163,18 @@ wakeup_gdt:
.word 0xffff /* 16-bit data segment @ real_mode_base */
.long 0x93000000 + pa_real_mode_base
.word 0x008f /* big real mode */
- .size wakeup_gdt, .-wakeup_gdt
+END(wakeup_gdt)
- .data
+ .section ".rodata","a"
.balign 8
/* This is the standard real-mode IDT */
-wakeup_idt:
+ .balign 16
+GLOBAL(wakeup_idt)
.word 0xffff /* limit */
.long 0 /* address */
.word 0
-
- .globl HEAP, heap_end
-HEAP:
- .long wakeup_heap
-heap_end:
- .long wakeup_stack
-
- .bss
-wakeup_heap:
- .space 2048
-wakeup_stack:
- .space 2048
-wakeup_stack_end:
+END(wakeup_idt)
.section ".signature","a"
end_signature:
diff --git a/arch/x86/realmode/rmpiggy.S b/arch/x86/realmode/rmpiggy.S
index 6047d7f..fd72a99 100644
--- a/arch/x86/realmode/rmpiggy.S
+++ b/arch/x86/realmode/rmpiggy.S
@@ -9,10 +9,10 @@
.balign PAGE_SIZE
-ENTRY(real_mode_blob)
+GLOBAL(real_mode_blob)
.incbin "arch/x86/realmode/rm/realmode.bin"
END(real_mode_blob)
-ENTRY(real_mode_relocs)
+GLOBAL(real_mode_relocs)
.incbin "arch/x86/realmode/rm/realmode.relocs"
END(real_mode_relocs)
--
1.7.9.5
--
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