On Mon, Jan 20, 2014 at 05:05:14PM +0000, Jean Pihet wrote:
Hi Will,
Here is an updated version of the change, which uses compat_sp at only one place. The drawback is that compat_user_mode is checked when calling compat_user_stack_pointer, which seems unnecessary. Unfortunately the check is not optimized out by the complier as I could check with objdump -S.
What do you think?
I think that's cleaner and really wouldn't worry about the couple of extra instructions.
Cheers,
Will
diff --git a/arch/arm64/include/asm/compat.h b/arch/arm64/include/asm/compat.h index fda2704..e71f81f 100644 --- a/arch/arm64/include/asm/compat.h +++ b/arch/arm64/include/asm/compat.h @@ -228,7 +228,7 @@ static inline compat_uptr_t ptr_to_compat(void __user *uptr) return (u32)(unsigned long)uptr; }
-#define compat_user_stack_pointer() (current_pt_regs()->compat_sp) +#define compat_user_stack_pointer() (user_stack_pointer(current_pt_regs()))
static inline void __user *arch_compat_alloc_user_space(long len) { diff --git a/arch/arm64/include/asm/ptrace.h b/arch/arm64/include/asm/ptrace.h index fbb0020..86d5b54 100644 --- a/arch/arm64/include/asm/ptrace.h +++ b/arch/arm64/include/asm/ptrace.h @@ -133,7 +133,7 @@ struct pt_regs { (!((regs)->pstate & PSR_F_BIT))
#define user_stack_pointer(regs) \
((regs)->sp)
(!compat_user_mode(regs)) ? ((regs)->sp) : ((regs)->compat_sp)/*
- Are the current registers suitable for user mode? (used to maintain