[RFC PATCH 18/19] powerpc: change stack marker memory operations to 32-bit
Nicholas Piggin
npiggin at gmail.com
Mon Oct 31 16:54:39 AEDT 2022
The marker is a 32-bit constant across all platforms now, so use 32-bit
memory accesses.
Signed-off-by: Nicholas Piggin <npiggin at gmail.com>
---
arch/powerpc/include/asm/ptrace.h | 1 -
arch/powerpc/kernel/exceptions-64e.S | 2 +-
arch/powerpc/kernel/exceptions-64s.S | 2 +-
arch/powerpc/kernel/interrupt_64.S | 6 +++---
arch/powerpc/kernel/process.c | 6 +++---
arch/powerpc/kernel/stacktrace.c | 2 +-
arch/powerpc/perf/callchain.c | 2 +-
7 files changed, 10 insertions(+), 11 deletions(-)
diff --git a/arch/powerpc/include/asm/ptrace.h b/arch/powerpc/include/asm/ptrace.h
index a53c580388e2..ab41d47761c9 100644
--- a/arch/powerpc/include/asm/ptrace.h
+++ b/arch/powerpc/include/asm/ptrace.h
@@ -162,7 +162,6 @@ struct pt_regs
#endif /* __powerpc64__ */
#define STACK_INT_FRAME_SIZE (KERNEL_REDZONE_SIZE + STACK_USER_INT_FRAME_SIZE)
-#define STACK_INT_FRAME_MARKER_LONGS (STACK_INT_FRAME_MARKER/sizeof(long))
#ifndef __ASSEMBLY__
#include <asm/paca.h>
diff --git a/arch/powerpc/kernel/exceptions-64e.S b/arch/powerpc/kernel/exceptions-64e.S
index d74c2a53af13..86cf656c6777 100644
--- a/arch/powerpc/kernel/exceptions-64e.S
+++ b/arch/powerpc/kernel/exceptions-64e.S
@@ -391,7 +391,7 @@ exc_##n##_common: \
std r10,_CCR(r1); /* store orig CR in stackframe */ \
std r9,GPR1(r1); /* store stack frame back link */ \
std r11,SOFTE(r1); /* and save it to stackframe */ \
- std r12,STACK_INT_FRAME_MARKER(r1); /* mark the frame */ \
+ stw r12,STACK_INT_FRAME_MARKER(r1); /* mark the frame */ \
std r3,_TRAP(r1); /* set trap number */ \
std r0,RESULT(r1); /* clear regs->result */ \
SAVE_NVGPRS(r1);
diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S
index 39f08ec56126..85bbdfa7e4d3 100644
--- a/arch/powerpc/kernel/exceptions-64s.S
+++ b/arch/powerpc/kernel/exceptions-64s.S
@@ -591,7 +591,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_CFAR)
li r10,0
LOAD_REG_IMMEDIATE(r11, STACK_FRAME_REGS_MARKER)
std r10,RESULT(r1) /* clear regs->result */
- std r11,STACK_INT_FRAME_MARKER(r1) /* mark the frame */
+ stw r11,STACK_INT_FRAME_MARKER(r1) /* mark the frame */
.endm
/*
diff --git a/arch/powerpc/kernel/interrupt_64.S b/arch/powerpc/kernel/interrupt_64.S
index 2306b979e71f..ee8cfe17ca37 100644
--- a/arch/powerpc/kernel/interrupt_64.S
+++ b/arch/powerpc/kernel/interrupt_64.S
@@ -78,7 +78,7 @@ _ASM_NOKPROBE_SYMBOL(system_call_vectored_\name)
std r12,_CCR(r1)
std r3,ORIG_GPR3(r1)
LOAD_REG_IMMEDIATE(r11, STACK_FRAME_REGS_MARKER)
- std r11,STACK_INT_FRAME_MARKER(r1) /* "regs" marker */
+ stw r11,STACK_INT_FRAME_MARKER(r1) /* "regs" marker */
/* Calling convention has r3 = regs, r4 = orig r0 */
addi r3,r1,STACK_INT_FRAME_REGS
mr r4,r0
@@ -251,7 +251,7 @@ END_BTB_FLUSH_SECTION
std r12,_CCR(r1)
std r3,ORIG_GPR3(r1)
LOAD_REG_IMMEDIATE(r11, STACK_FRAME_REGS_MARKER)
- std r11,STACK_INT_FRAME_MARKER(r1) /* "regs" marker */
+ stw r11,STACK_INT_FRAME_MARKER(r1) /* "regs" marker */
/* Calling convention has r3 = regs, r4 = orig r0 */
addi r3,r1,STACK_INT_FRAME_REGS
mr r4,r0
@@ -628,7 +628,7 @@ ALT_FTR_SECTION_END_IFCLR(CPU_FTR_STCX_CHECKS_ADDRESS)
* Leaving a stale STACK_FRAME_REGS_MARKER on the stack can confuse
* the reliable stack unwinder later on. Clear it.
*/
- std r0,STACK_INT_FRAME_MARKER(r1)
+ stw r0,STACK_INT_FRAME_MARKER(r1)
REST_GPRS(2, 5, r1)
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index 20fdb84759f0..e447bf02f996 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -1728,7 +1728,7 @@ int copy_thread(struct task_struct *p, const struct kernel_clone_args *args)
/* Create initial stack frame. */
sp -= STACK_USER_INT_FRAME_SIZE;
- *(unsigned long *)(sp + STACK_INT_FRAME_MARKER) = STACK_FRAME_REGS_MARKER;
+ *(u32 *)(sp + STACK_INT_FRAME_MARKER) = STACK_FRAME_REGS_MARKER;
/* Copy registers */
childregs = (struct pt_regs *)(sp + STACK_INT_FRAME_REGS);
@@ -2246,8 +2246,8 @@ void __no_sanitize_address show_stack(struct task_struct *tsk,
* could hold a pt_regs, if that does not fit then it can't
* have regs.
*/
- if (validate_sp_size(sp, tsk, STACK_SWITCH_FRAME_SIZE)
- && stack[STACK_INT_FRAME_MARKER_LONGS] == STACK_FRAME_REGS_MARKER) {
+ if (validate_sp_size(sp, tsk, STACK_SWITCH_FRAME_SIZE) &&
+ *(u32 *)(sp + STACK_INT_FRAME_MARKER) == STACK_FRAME_REGS_MARKER) {
struct pt_regs *regs = (struct pt_regs *)
(sp + STACK_INT_FRAME_REGS);
diff --git a/arch/powerpc/kernel/stacktrace.c b/arch/powerpc/kernel/stacktrace.c
index 5de8597eaab8..7d975943f5ec 100644
--- a/arch/powerpc/kernel/stacktrace.c
+++ b/arch/powerpc/kernel/stacktrace.c
@@ -136,7 +136,7 @@ int __no_sanitize_address arch_stack_walk_reliable(stack_trace_consume_fn consum
/* Mark stacktraces with exception frames as unreliable. */
if (sp <= stack_end - STACK_INT_FRAME_SIZE &&
- stack[STACK_INT_FRAME_MARKER_LONGS] == STACK_FRAME_REGS_MARKER) {
+ *(u32 *)(sp + STACK_INT_FRAME_MARKER) == STACK_FRAME_REGS_MARKER) {
return -EINVAL;
}
diff --git a/arch/powerpc/perf/callchain.c b/arch/powerpc/perf/callchain.c
index 6b4434dd0ff3..72eef9accdbb 100644
--- a/arch/powerpc/perf/callchain.c
+++ b/arch/powerpc/perf/callchain.c
@@ -62,7 +62,7 @@ perf_callchain_kernel(struct perf_callchain_entry_ctx *entry, struct pt_regs *re
if (next_sp == sp + STACK_INT_FRAME_SIZE &&
validate_sp_size(sp, current, STACK_INT_FRAME_SIZE) &&
- fp[STACK_INT_FRAME_MARKER_LONGS] == STACK_FRAME_REGS_MARKER) {
+ *(u32 *)(sp + STACK_INT_FRAME_MARKER) == STACK_FRAME_REGS_MARKER) {
/*
* This looks like an interrupt frame for an
* interrupt that occurred in the kernel
--
2.37.2
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