2022-10-21 11:36:09

by Tong Tiangen

Subject: [PATCH -next] csky: add arch support current_stack_pointer

To follow the existing per-arch conventions, using "current_stack_pointer"
to set sp.

This will let it be used in non-arch places(like HARDENED_USERCOPY).

Signed-off-by: Tong Tiangen <[email protected]>
---
arch/csky/Kconfig | 1 +
arch/csky/include/asm/processor.h | 2 ++
arch/csky/kernel/stacktrace.c | 6 ++----
3 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/arch/csky/Kconfig b/arch/csky/Kconfig
index adee6ab36862..2236b5c0c213 100644
--- a/arch/csky/Kconfig
+++ b/arch/csky/Kconfig
@@ -9,6 +9,7 @@ config CSKY
select ARCH_USE_BUILTIN_BSWAP
select ARCH_USE_QUEUED_RWLOCKS
select ARCH_USE_QUEUED_SPINLOCKS
+ select ARCH_HAS_CURRENT_STACK_POINTER
select ARCH_INLINE_READ_LOCK if !PREEMPTION
select ARCH_INLINE_READ_LOCK_BH if !PREEMPTION
select ARCH_INLINE_READ_LOCK_IRQ if !PREEMPTION
diff --git a/arch/csky/include/asm/processor.h b/arch/csky/include/asm/processor.h
index 63ad71fab30d..ea75d72dea86 100644
--- a/arch/csky/include/asm/processor.h
+++ b/arch/csky/include/asm/processor.h
@@ -84,4 +84,6 @@ unsigned long __get_wchan(struct task_struct *p);

#define cpu_relax() barrier()

+register unsigned long current_stack_pointer __asm__("sp");
+
#endif /* __ASM_CSKY_PROCESSOR_H */
diff --git a/arch/csky/kernel/stacktrace.c b/arch/csky/kernel/stacktrace.c
index 9f78f5d21511..27ecd63e321b 100644
--- a/arch/csky/kernel/stacktrace.c
+++ b/arch/csky/kernel/stacktrace.c
@@ -23,10 +23,9 @@ void notrace walk_stackframe(struct task_struct *task, struct pt_regs *regs,
sp = user_stack_pointer(regs);
pc = instruction_pointer(regs);
} else if (task == NULL || task == current) {
- const register unsigned long current_sp __asm__ ("sp");
const register unsigned long current_fp __asm__ ("r8");
fp = current_fp;
- sp = current_sp;
+ sp = current_stack_pointer;
pc = (unsigned long)walk_stackframe;
} else {
/* task blocked in __switch_to */
@@ -68,8 +67,7 @@ static void notrace walk_stackframe(struct task_struct *task,
sp = user_stack_pointer(regs);
pc = instruction_pointer(regs);
} else if (task == NULL || task == current) {
- const register unsigned long current_sp __asm__ ("sp");
- sp = current_sp;
+ sp = current_stack_pointer;
pc = (unsigned long)walk_stackframe;
} else {
/* task blocked in __switch_to */
--
2.25.1

2022-10-21 15:02:51

by Guo Ren

Subject: Re: [PATCH -next] csky: add arch support current_stack_pointer

On Fri, Oct 21, 2022 at 7:31 PM Tong Tiangen <[email protected]> wrote:
>
> To follow the existing per-arch conventions, using "current_stack_pointer"
> to set sp.
>
> This will let it be used in non-arch places(like HARDENED_USERCOPY).
>

Add a Link tag here. The original patch series lore.kernel.org link.
One tip: commit fdecfea09328b33fd08a4d418237cce9fd176d69 riscv: Rename
"sp_in_global" to "current_stack_pointer"

To follow the existing per-arch conventions, rename "sp_in_global" to
"current_stack_pointer". This will let it be used in non-arch places
(like HARDENED_USERCOPY).
> Signed-off-by: Tong Tiangen <[email protected]>
> ---
> arch/csky/Kconfig | 1 +
> arch/csky/include/asm/processor.h | 2 ++
> arch/csky/kernel/stacktrace.c | 6 ++----
> 3 files changed, 5 insertions(+), 4 deletions(-)
>
> diff --git a/arch/csky/Kconfig b/arch/csky/Kconfig
> index adee6ab36862..2236b5c0c213 100644
> --- a/arch/csky/Kconfig
> +++ b/arch/csky/Kconfig
> @@ -9,6 +9,7 @@ config CSKY
> select ARCH_USE_BUILTIN_BSWAP
> select ARCH_USE_QUEUED_RWLOCKS
> select ARCH_USE_QUEUED_SPINLOCKS
> + select ARCH_HAS_CURRENT_STACK_POINTER
> select ARCH_INLINE_READ_LOCK if !PREEMPTION
> select ARCH_INLINE_READ_LOCK_BH if !PREEMPTION
> select ARCH_INLINE_READ_LOCK_IRQ if !PREEMPTION
> diff --git a/arch/csky/include/asm/processor.h b/arch/csky/include/asm/processor.h
> index 63ad71fab30d..ea75d72dea86 100644
> --- a/arch/csky/include/asm/processor.h
> +++ b/arch/csky/include/asm/processor.h
> @@ -84,4 +84,6 @@ unsigned long __get_wchan(struct task_struct *p);
>
> #define cpu_relax() barrier()
>
> +register unsigned long current_stack_pointer __asm__("sp");
> +
> #endif /* __ASM_CSKY_PROCESSOR_H */
> diff --git a/arch/csky/kernel/stacktrace.c b/arch/csky/kernel/stacktrace.c
> index 9f78f5d21511..27ecd63e321b 100644
> --- a/arch/csky/kernel/stacktrace.c
> +++ b/arch/csky/kernel/stacktrace.c
> @@ -23,10 +23,9 @@ void notrace walk_stackframe(struct task_struct *task, struct pt_regs *regs,
> sp = user_stack_pointer(regs);
> pc = instruction_pointer(regs);
> } else if (task == NULL || task == current) {
> - const register unsigned long current_sp __asm__ ("sp");
> const register unsigned long current_fp __asm__ ("r8");
> fp = current_fp;
> - sp = current_sp;
> + sp = current_stack_pointer;
> pc = (unsigned long)walk_stackframe;
> } else {
> /* task blocked in __switch_to */
> @@ -68,8 +67,7 @@ static void notrace walk_stackframe(struct task_struct *task,
> sp = user_stack_pointer(regs);
> pc = instruction_pointer(regs);
> } else if (task == NULL || task == current) {
> - const register unsigned long current_sp __asm__ ("sp");
> - sp = current_sp;
> + sp = current_stack_pointer;
> pc = (unsigned long)walk_stackframe;
> } else {
> /* task blocked in __switch_to */
> --
> 2.25.1
>


--
Best Regards
Guo Ren

2022-10-21 15:54:46

by Tong Tiangen

Subject: Re: [PATCH -next] csky: add arch support current_stack_pointer

在 2022/10/21 22:48, Guo Ren 写道:
> On Fri, Oct 21, 2022 at 7:31 PM Tong Tiangen <[email protected]> wrote:
>>
>> To follow the existing per-arch conventions, using "current_stack_pointer"
>> to set sp.
>>
>> This will let it be used in non-arch places(like HARDENED_USERCOPY).
>>
>
> Add a Link tag here. The original patch series lore.kernel.org link.
> One tip: commit fdecfea09328b33fd08a4d418237cce9fd176d69 riscv: Rename
> "sp_in_global" to "current_stack_pointer"
>
> To follow the existing per-arch conventions, rename "sp_in_global" to
> "current_stack_pointer". This will let it be used in non-arch places
> (like HARDENED_USERCOPY).

Hi guo:

Ok, Will be added in v2.

Thanks.
Tong.

>> Signed-off-by: Tong Tiangen <[email protected]>
>> ---
>> arch/csky/Kconfig | 1 +
>> arch/csky/include/asm/processor.h | 2 ++
>> arch/csky/kernel/stacktrace.c | 6 ++----
>> 3 files changed, 5 insertions(+), 4 deletions(-)
>>
>> diff --git a/arch/csky/Kconfig b/arch/csky/Kconfig
>> index adee6ab36862..2236b5c0c213 100644
>> --- a/arch/csky/Kconfig
>> +++ b/arch/csky/Kconfig
>> @@ -9,6 +9,7 @@ config CSKY
>> select ARCH_USE_BUILTIN_BSWAP
>> select ARCH_USE_QUEUED_RWLOCKS
>> select ARCH_USE_QUEUED_SPINLOCKS
>> + select ARCH_HAS_CURRENT_STACK_POINTER
>> select ARCH_INLINE_READ_LOCK if !PREEMPTION
>> select ARCH_INLINE_READ_LOCK_BH if !PREEMPTION
>> select ARCH_INLINE_READ_LOCK_IRQ if !PREEMPTION
>> diff --git a/arch/csky/include/asm/processor.h b/arch/csky/include/asm/processor.h
>> index 63ad71fab30d..ea75d72dea86 100644
>> --- a/arch/csky/include/asm/processor.h
>> +++ b/arch/csky/include/asm/processor.h
>> @@ -84,4 +84,6 @@ unsigned long __get_wchan(struct task_struct *p);
>>
>> #define cpu_relax() barrier()
>>
>> +register unsigned long current_stack_pointer __asm__("sp");
>> +
>> #endif /* __ASM_CSKY_PROCESSOR_H */
>> diff --git a/arch/csky/kernel/stacktrace.c b/arch/csky/kernel/stacktrace.c
>> index 9f78f5d21511..27ecd63e321b 100644
>> --- a/arch/csky/kernel/stacktrace.c
>> +++ b/arch/csky/kernel/stacktrace.c
>> @@ -23,10 +23,9 @@ void notrace walk_stackframe(struct task_struct *task, struct pt_regs *regs,
>> sp = user_stack_pointer(regs);
>> pc = instruction_pointer(regs);
>> } else if (task == NULL || task == current) {
>> - const register unsigned long current_sp __asm__ ("sp");
>> const register unsigned long current_fp __asm__ ("r8");
>> fp = current_fp;
>> - sp = current_sp;
>> + sp = current_stack_pointer;
>> pc = (unsigned long)walk_stackframe;
>> } else {
>> /* task blocked in __switch_to */
>> @@ -68,8 +67,7 @@ static void notrace walk_stackframe(struct task_struct *task,
>> sp = user_stack_pointer(regs);
>> pc = instruction_pointer(regs);
>> } else if (task == NULL || task == current) {
>> - const register unsigned long current_sp __asm__ ("sp");
>> - sp = current_sp;
>> + sp = current_stack_pointer;
>> pc = (unsigned long)walk_stackframe;
>> } else {
>> /* task blocked in __switch_to */
>> --
>> 2.25.1
>>
>
>