2020-05-08 03:20:14

by Yunfeng Ye

Subject: [PATCH v2] arm64: stacktrace: Factor out some common code into on_stack()

There are some common codes for stack checking, so factors it out into
the function on_stack().

No functional change.

Signed-off-by: Yunfeng Ye <[email protected]>
---
v1 -> v2:
- check 'low' in on_stack() and everybody call on_stack() only

arch/arm64/include/asm/stacktrace.h | 40 +++++++++++++------------------------
arch/arm64/kernel/sdei.c | 28 ++------------------------
2 files changed, 16 insertions(+), 52 deletions(-)

diff --git a/arch/arm64/include/asm/stacktrace.h b/arch/arm64/include/asm/stacktrace.h
index fdb913cc0bcb..fc7613023c19 100644
--- a/arch/arm64/include/asm/stacktrace.h
+++ b/arch/arm64/include/asm/stacktrace.h
@@ -69,12 +69,10 @@ extern void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk,

DECLARE_PER_CPU(unsigned long *, irq_stack_ptr);

-static inline bool on_irq_stack(unsigned long sp,
+static inline bool on_stack(unsigned long sp, unsigned long low,
+ unsigned long high, enum stack_type type,
struct stack_info *info)
{
- unsigned long low = (unsigned long)raw_cpu_read(irq_stack_ptr);
- unsigned long high = low + IRQ_STACK_SIZE;
-
if (!low)
return false;

@@ -84,12 +82,20 @@ static inline bool on_irq_stack(unsigned long sp,
if (info) {
info->low = low;
info->high = high;
- info->type = STACK_TYPE_IRQ;
+ info->type = type;
}
-
return true;
}

+static inline bool on_irq_stack(unsigned long sp,
+ struct stack_info *info)
+{
+ unsigned long low = (unsigned long)raw_cpu_read(irq_stack_ptr);
+ unsigned long high = low + IRQ_STACK_SIZE;
+
+ return on_stack(sp, low, high, STACK_TYPE_IRQ, info);
+}
+
static inline bool on_task_stack(const struct task_struct *tsk,
unsigned long sp,
struct stack_info *info)
@@ -97,16 +103,7 @@ static inline bool on_task_stack(const struct task_struct *tsk,
unsigned long low = (unsigned long)task_stack_page(tsk);
unsigned long high = low + THREAD_SIZE;

- if (sp < low || sp >= high)
- return false;
-
- if (info) {
- info->low = low;
- info->high = high;
- info->type = STACK_TYPE_TASK;
- }
-
- return true;
+ return on_stack(sp, low, high, STACK_TYPE_TASK, info);
}

#ifdef CONFIG_VMAP_STACK
@@ -118,16 +115,7 @@ static inline bool on_overflow_stack(unsigned long sp,
unsigned long low = (unsigned long)raw_cpu_ptr(overflow_stack);
unsigned long high = low + OVERFLOW_STACK_SIZE;

- if (sp < low || sp >= high)
- return false;
-
- if (info) {
- info->low = low;
- info->high = high;
- info->type = STACK_TYPE_OVERFLOW;
- }
-
- return true;
+ return on_stack(sp, low, high, STACK_TYPE_OVERFLOW, info);
}
#else
static inline bool on_overflow_stack(unsigned long sp,
diff --git a/arch/arm64/kernel/sdei.c b/arch/arm64/kernel/sdei.c
index d6259dac62b6..3afed808b474 100644
--- a/arch/arm64/kernel/sdei.c
+++ b/arch/arm64/kernel/sdei.c
@@ -95,19 +95,7 @@ static bool on_sdei_normal_stack(unsigned long sp, struct stack_info *info)
unsigned long low = (unsigned long)raw_cpu_read(sdei_stack_normal_ptr);
unsigned long high = low + SDEI_STACK_SIZE;

- if (!low)
- return false;
-
- if (sp < low || sp >= high)
- return false;
-
- if (info) {
- info->low = low;
- info->high = high;
- info->type = STACK_TYPE_SDEI_NORMAL;
- }
-
- return true;
+ return on_stack(sp, low, high, STACK_TYPE_SDEI_NORMAL, info);
}

static bool on_sdei_critical_stack(unsigned long sp, struct stack_info *info)
@@ -115,19 +103,7 @@ static bool on_sdei_critical_stack(unsigned long sp, struct stack_info *info)
unsigned long low = (unsigned long)raw_cpu_read(sdei_stack_critical_ptr);
unsigned long high = low + SDEI_STACK_SIZE;

- if (!low)
- return false;
-
- if (sp < low || sp >= high)
- return false;
-
- if (info) {
- info->low = low;
- info->high = high;
- info->type = STACK_TYPE_SDEI_CRITICAL;
- }
-
- return true;
+ return on_stack(sp, low, high, STACK_TYPE_SDEI_CRITICAL, info);
}

bool _on_sdei_stack(unsigned long sp, struct stack_info *info)
--
1.8.3.1

2020-05-18 23:06:28

by Will Deacon

Subject: Re: [PATCH v2] arm64: stacktrace: Factor out some common code into on_stack()

On Fri, 8 May 2020 11:15:45 +0800, Yunfeng Ye wrote:
> There are some common codes for stack checking, so factors it out into
> the function on_stack().
>
> No functional change.

Applied to arm64 (for-next/misc), thanks!

[1/1] arm64: stacktrace: Factor out some common code into on_stack()
https://git.kernel.org/arm64/c/bd4298c72b56

Cheers,
--
Will

https://fixes.arm64.dev
https://next.arm64.dev
https://will.arm64.dev