[PATCH v6 3/4] sparc64: Add support for ADI register fields, ASIs and traps
From: Khalid Aziz
Date: Tue Feb 28 2017 - 13:39:25 EST
SPARC M7 processor adds new control register fields, ASIs and a new
trap to support the ADI (Application Data Integrity) feature. This
patch adds definitions for these register fields, ASIs and a handler
for the new precise memory corruption detected trap.
Signed-off-by: Khalid Aziz <khalid.aziz@xxxxxxxxxx>
Cc: Khalid Aziz <khalid@xxxxxxxxxxxxxx>
---
v6:
- Added a missing nop in the delay slot in sun4v_mcd_detect_precise
v5:
- Fixed indentation issues in assembly code
v4:
- Broke patch up into smaller patches
v3:
- Removed CONFIG_SPARC_ADI
- Replaced prctl commands with mprotect
- Added auxiliary vectors for ADI parameters
- Enabled ADI for swappable pages
v2:
- Fixed a build error
arch/sparc/include/asm/hypervisor.h | 2 ++
arch/sparc/include/asm/pgtable_64.h | 2 ++
arch/sparc/include/asm/ttable.h | 10 +++++++
arch/sparc/include/uapi/asm/asi.h | 5 ++++
arch/sparc/include/uapi/asm/pstate.h | 10 +++++++
arch/sparc/kernel/entry.h | 3 ++
arch/sparc/kernel/head_64.S | 1 +
arch/sparc/kernel/sun4v_mcd.S | 17 ++++++++++++
arch/sparc/kernel/traps_64.c | 54 ++++++++++++++++++++++++++++++++++++
arch/sparc/kernel/ttable_64.S | 6 ++--
10 files changed, 108 insertions(+), 2 deletions(-)
create mode 100644 arch/sparc/kernel/sun4v_mcd.S
diff --git a/arch/sparc/include/asm/hypervisor.h b/arch/sparc/include/asm/hypervisor.h
index 73cb897..31782f7 100644
--- a/arch/sparc/include/asm/hypervisor.h
+++ b/arch/sparc/include/asm/hypervisor.h
@@ -547,6 +547,8 @@ struct hv_fault_status {
#define HV_FAULT_TYPE_RESV1 13
#define HV_FAULT_TYPE_UNALIGNED 14
#define HV_FAULT_TYPE_INV_PGSZ 15
+#define HV_FAULT_TYPE_MCD 17
+#define HV_FAULT_TYPE_MCD_DIS 18
/* Values 16 --> -2 are reserved. */
#define HV_FAULT_TYPE_MULTIPLE -1
diff --git a/arch/sparc/include/asm/pgtable_64.h b/arch/sparc/include/asm/pgtable_64.h
index 314b668..569768d 100644
--- a/arch/sparc/include/asm/pgtable_64.h
+++ b/arch/sparc/include/asm/pgtable_64.h
@@ -162,6 +162,8 @@ bool kern_addr_valid(unsigned long addr);
#define _PAGE_E_4V _AC(0x0000000000000800,UL) /* side-Effect */
#define _PAGE_CP_4V _AC(0x0000000000000400,UL) /* Cacheable in P-Cache */
#define _PAGE_CV_4V _AC(0x0000000000000200,UL) /* Cacheable in V-Cache */
+/* Bit 9 is used to enable MCD corruption detection instead on M7 */
+#define _PAGE_MCD_4V _AC(0x0000000000000200,UL) /* Memory Corruption */
#define _PAGE_P_4V _AC(0x0000000000000100,UL) /* Privileged Page */
#define _PAGE_EXEC_4V _AC(0x0000000000000080,UL) /* Executable Page */
#define _PAGE_W_4V _AC(0x0000000000000040,UL) /* Writable */
diff --git a/arch/sparc/include/asm/ttable.h b/arch/sparc/include/asm/ttable.h
index 82e7df2..d6510ab 100644
--- a/arch/sparc/include/asm/ttable.h
+++ b/arch/sparc/include/asm/ttable.h
@@ -218,6 +218,16 @@
nop; \
nop;
+#define SUN4V_MCD_PRECISE \
+ ldxa [%g0] ASI_SCRATCHPAD, %g2; \
+ ldx [%g2 + HV_FAULT_D_ADDR_OFFSET], %g4; \
+ ldx [%g2 + HV_FAULT_D_CTX_OFFSET], %g5; \
+ ba,pt %xcc, etrap; \
+ rd %pc, %g7; \
+ ba,pt %xcc, sun4v_mcd_detect_precise; \
+ nop; \
+ nop;
+
/* Before touching these macros, you owe it to yourself to go and
* see how arch/sparc64/kernel/winfixup.S works... -DaveM
*
diff --git a/arch/sparc/include/uapi/asm/asi.h b/arch/sparc/include/uapi/asm/asi.h
index 7ad7203d..2bcdaa5 100644
--- a/arch/sparc/include/uapi/asm/asi.h
+++ b/arch/sparc/include/uapi/asm/asi.h
@@ -144,6 +144,8 @@
* ASIs, "(4V)" designates SUN4V specific ASIs. "(NG4)" designates SPARC-T4
* and later ASIs.
*/
+#define ASI_MCD_PRIV_PRIMARY 0x02 /* (NG7) Privileged MCD version VA */
+#define ASI_MCD_REAL 0x05 /* (NG7) Privileged MCD version PA */
#define ASI_PHYS_USE_EC 0x14 /* PADDR, E-cachable */
#define ASI_PHYS_BYPASS_EC_E 0x15 /* PADDR, E-bit */
#define ASI_BLK_AIUP_4V 0x16 /* (4V) Prim, user, block ld/st */
@@ -244,6 +246,9 @@
#define ASI_UDBL_CONTROL_R 0x7f /* External UDB control regs rd low*/
#define ASI_INTR_R 0x7f /* IRQ vector dispatch read */
#define ASI_INTR_DATAN_R 0x7f /* (III) In irq vector data reg N */
+#define ASI_MCD_PRIMARY 0x90 /* (NG7) MCD version load/store */
+#define ASI_MCD_ST_BLKINIT_PRIMARY \
+ 0x92 /* (NG7) MCD store BLKINIT primary */
#define ASI_PIC 0xb0 /* (NG4) PIC registers */
#define ASI_PST8_P 0xc0 /* Primary, 8 8-bit, partial */
#define ASI_PST8_S 0xc1 /* Secondary, 8 8-bit, partial */
diff --git a/arch/sparc/include/uapi/asm/pstate.h b/arch/sparc/include/uapi/asm/pstate.h
index cf832e1..d0521db 100644
--- a/arch/sparc/include/uapi/asm/pstate.h
+++ b/arch/sparc/include/uapi/asm/pstate.h
@@ -10,7 +10,12 @@
* -----------------------------------------------------------------------
* 63 12 11 10 9 8 7 6 5 4 3 2 1 0
*/
+/* IG on V9 conflicts with MCDE on M7. PSTATE_MCDE will only be used on
+ * processors that support ADI which do not use IG, hence there is no
+ * functional conflict
+ */
#define PSTATE_IG _AC(0x0000000000000800,UL) /* Interrupt Globals. */
+#define PSTATE_MCDE _AC(0x0000000000000800,UL) /* MCD Enable */
#define PSTATE_MG _AC(0x0000000000000400,UL) /* MMU Globals. */
#define PSTATE_CLE _AC(0x0000000000000200,UL) /* Current Little Endian.*/
#define PSTATE_TLE _AC(0x0000000000000100,UL) /* Trap Little Endian. */
@@ -47,7 +52,12 @@
#define TSTATE_ASI _AC(0x00000000ff000000,UL) /* AddrSpace ID. */
#define TSTATE_PIL _AC(0x0000000000f00000,UL) /* %pil (Linux traps)*/
#define TSTATE_PSTATE _AC(0x00000000000fff00,UL) /* PSTATE. */
+/* IG on V9 conflicts with MCDE on M7. TSTATE_MCDE will only be used on
+ * processors that support ADI which do not support IG, hence there is
+ * no functional conflict
+ */
#define TSTATE_IG _AC(0x0000000000080000,UL) /* Interrupt Globals.*/
+#define TSTATE_MCDE _AC(0x0000000000080000,UL) /* MCD enable. */
#define TSTATE_MG _AC(0x0000000000040000,UL) /* MMU Globals. */
#define TSTATE_CLE _AC(0x0000000000020000,UL) /* CurrLittleEndian. */
#define TSTATE_TLE _AC(0x0000000000010000,UL) /* TrapLittleEndian. */
diff --git a/arch/sparc/kernel/entry.h b/arch/sparc/kernel/entry.h
index 0f67942..2078468 100644
--- a/arch/sparc/kernel/entry.h
+++ b/arch/sparc/kernel/entry.h
@@ -159,6 +159,9 @@ void sun4v_resum_overflow(struct pt_regs *regs);
void sun4v_nonresum_error(struct pt_regs *regs,
unsigned long offset);
void sun4v_nonresum_overflow(struct pt_regs *regs);
+void sun4v_mem_corrupt_detect_precise(struct pt_regs *regs,
+ unsigned long addr,
+ unsigned long context);
extern unsigned long sun4v_err_itlb_vaddr;
extern unsigned long sun4v_err_itlb_ctx;
diff --git a/arch/sparc/kernel/head_64.S b/arch/sparc/kernel/head_64.S
index 6aa3da1..818f869 100644
--- a/arch/sparc/kernel/head_64.S
+++ b/arch/sparc/kernel/head_64.S
@@ -873,6 +873,7 @@ sparc64_boot_end:
#include "helpers.S"
#include "hvcalls.S"
#include "sun4v_tlb_miss.S"
+#include "sun4v_mcd.S"
#include "sun4v_ivec.S"
#include "ktlb.S"
#include "tsb.S"
diff --git a/arch/sparc/kernel/sun4v_mcd.S b/arch/sparc/kernel/sun4v_mcd.S
new file mode 100644
index 0000000..92afb62
--- /dev/null
+++ b/arch/sparc/kernel/sun4v_mcd.S
@@ -0,0 +1,17 @@
+/* sun4v_mcd.S: Sun4v memory corruption detected precise exception handler
+ *
+ * Copyright (C) 2015 Bob Picco <bob.picco@xxxxxxxxxx>
+ * Copyright (C) 2015 Khalid Aziz <khalid.aziz@xxxxxxxxxx>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2.
+ */
+ .text
+ .align 32
+
+sun4v_mcd_detect_precise:
+ mov %l4, %o1
+ mov %l5, %o2
+ call sun4v_mem_corrupt_detect_precise
+ add %sp, PTREGS_OFF, %o0
+ ba,a,pt %xcc, rtrap
+ nop
diff --git a/arch/sparc/kernel/traps_64.c b/arch/sparc/kernel/traps_64.c
index dfc97a4..a9a71d5 100644
--- a/arch/sparc/kernel/traps_64.c
+++ b/arch/sparc/kernel/traps_64.c
@@ -2604,6 +2604,60 @@ void sun4v_do_mna(struct pt_regs *regs, unsigned long addr, unsigned long type_c
force_sig_info(SIGBUS, &info, current);
}
+/* sun4v_mem_corrupt_detect_precise() - Handle precise exception on an ADI
+ * tag mismatch.
+ *
+ * ADI version tag mismatch on a load from memory always results in a
+ * precise exception. Tag mismatch on a store to memory will result in
+ * precise exception if MCDPER or PMCDPER is set to 1.
+ */
+void sun4v_mem_corrupt_detect_precise(struct pt_regs *regs, unsigned long addr,
+ unsigned long context)
+{
+ siginfo_t info;
+
+ if (notify_die(DIE_TRAP, "memory corruption precise exception", regs,
+ 0, 0x8, SIGSEGV) == NOTIFY_STOP)
+ return;
+
+ if (regs->tstate & TSTATE_PRIV) {
+ /* MCD exception could happen because the task was running
+ * a system call with MCD enabled and passed a non-versioned
+ * pointer or pointer with bad version tag to the system
+ * call.
+ */
+ const struct exception_table_entry *entry;
+
+ entry = search_exception_tables(regs->tpc);
+ if (entry) {
+ /* Looks like a bad syscall parameter */
+#ifdef DEBUG_EXCEPTIONS
+ pr_emerg("Exception: PC<%016lx> faddr<UNKNOWN>\n",
+ regs->tpc);
+ pr_emerg("EX_TABLE: insn<%016lx> fixup<%016lx>\n",
+ regs->tpc, entry->fixup);
+#endif
+ regs->tpc = entry->fixup;
+ regs->tnpc = regs->tpc + 4;
+ return;
+ }
+ pr_emerg("sun4v_mem_corrupt_detect_precise: ADDR[%016lx] "
+ "CTX[%lx], going.\n", addr, context);
+ die_if_kernel("MCD precise", regs);
+ }
+
+ if (test_thread_flag(TIF_32BIT)) {
+ regs->tpc &= 0xffffffff;
+ regs->tnpc &= 0xffffffff;
+ }
+ info.si_signo = SIGSEGV;
+ info.si_code = SEGV_ADIPERR;
+ info.si_errno = 0;
+ info.si_addr = (void __user *) addr;
+ info.si_trapno = 0;
+ force_sig_info(SIGSEGV, &info, current);
+}
+
void do_privop(struct pt_regs *regs)
{
enum ctx_state prev_state = exception_enter();
diff --git a/arch/sparc/kernel/ttable_64.S b/arch/sparc/kernel/ttable_64.S
index 7bd8f65..37dea19 100644
--- a/arch/sparc/kernel/ttable_64.S
+++ b/arch/sparc/kernel/ttable_64.S
@@ -25,8 +25,10 @@ tl0_ill: membar #Sync
TRAP_7INSNS(do_illegal_instruction)
tl0_privop: TRAP(do_privop)
tl0_resv012: BTRAP(0x12) BTRAP(0x13) BTRAP(0x14) BTRAP(0x15) BTRAP(0x16) BTRAP(0x17)
-tl0_resv018: BTRAP(0x18) BTRAP(0x19) BTRAP(0x1a) BTRAP(0x1b) BTRAP(0x1c) BTRAP(0x1d)
-tl0_resv01e: BTRAP(0x1e) BTRAP(0x1f)
+tl0_resv018: BTRAP(0x18) BTRAP(0x19)
+tl0_mcd: SUN4V_MCD_PRECISE
+tl0_resv01b: BTRAP(0x1b)
+tl0_resv01c: BTRAP(0x1c) BTRAP(0x1d) BTRAP(0x1e) BTRAP(0x1f)
tl0_fpdis: TRAP_NOSAVE(do_fpdis)
tl0_fpieee: TRAP_SAVEFPU(do_fpieee)
tl0_fpother: TRAP_NOSAVE(do_fpother_check_fitos)
--
2.7.4