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

[Tong Tiangen]

在 2022/10/21 22:48, Guo Ren 写道:
> On Fri, Oct 21, 2022 at 7:31 PM Tong Tiangen <tongtiangen@xxxxxxxxxx> 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 <tongtiangen@xxxxxxxxxx>
> > ---
> >   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