2020-07-07 12:36:23

by Christophe Leroy

Subject: [PATCH 1/2] powerpc/signal_32: Remove !FULL_REGS() special handling in PPC64 save_general_regs()

Since commit ("1bd79336a426 powerpc: Fix various
syscall/signal/swapcontext bugs"), getting save_general_regs() called
without FULL_REGS() is very unlikely and generates a warning.

The 32-bit version of save_general_regs() doesn't take care of it
at all and copies all registers anyway since that commit.

Moreover, commit 965dd3ad3076 ("powerpc/64/syscall: Remove
non-volatile GPR save optimisation") is another reason why it would
never happen.

So the same with 64-bit, don't worry about FULL_REGS() and copy
all registers all the time.

Signed-off-by: Christophe Leroy <[email protected]>
---
arch/powerpc/kernel/signal_32.c | 2 --
1 file changed, 2 deletions(-)

diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index 1415c16ab628..0fd59fbc6d49 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -109,8 +109,6 @@ static inline int save_general_regs(struct pt_regs *regs,
WARN_ON(!FULL_REGS(regs));

for (i = 0; i <= PT_RESULT; i ++) {
- if (i == 14 && !FULL_REGS(regs))
- i = 32;
if ( i == PT_SOFTE) {
if(__put_user((unsigned int)softe, &frame->mc_gregs[i]))
return -EFAULT;
--
2.25.0

2020-07-16 13:00:13

by Michael Ellerman

Subject: Re: [PATCH 1/2] powerpc/signal_32: Remove !FULL_REGS() special handling in PPC64 save_general_regs()

On Tue, 7 Jul 2020 12:33:35 +0000 (UTC), Christophe Leroy wrote:
> Since commit ("1bd79336a426 powerpc: Fix various
> syscall/signal/swapcontext bugs"), getting save_general_regs() called
> without FULL_REGS() is very unlikely and generates a warning.
>
> The 32-bit version of save_general_regs() doesn't take care of it
> at all and copies all registers anyway since that commit.
>
> [...]

Applied to powerpc/next.

[1/2] powerpc/signal_32: Remove !FULL_REGS() special handling in PPC64 save_general_regs()
https://git.kernel.org/powerpc/c/667e3c413ecf20371692fd2dc37e06dc14d0b140
[2/2] powerpc/signal_32: Simplify loop in PPC64 save_general_regs()
https://git.kernel.org/powerpc/c/020c4831e01264f8b62af6ca9e669b7c51881a56

cheers