Re: [PATCH v5 11/22] powerpc/syscall: Save r3 in regs->orig_r3

Nicholas Piggin
2021-02-09T01:30:31Z

Excerpts from Christophe Leroy's message of February 9, 2021 1:10 am:
> Save r3 in regs->orig_r3 in system_call_exception()
>
> Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>

Reviewed-by: Nicholas Piggin <npiggin@gmail.com>

> ---
> v5: Removed the assembly one on SCV type system call
> ---
> arch/powerpc/kernel/entry_64.S | 2 --
> arch/powerpc/kernel/interrupt.c | 2 ++
> 2 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S
> index 33ddfeef4fe9..a91c2def165d 100644
> --- a/arch/powerpc/kernel/entry_64.S
> +++ b/arch/powerpc/kernel/entry_64.S
> @@ -108,7 +108,6 @@ END_FTR_SECTION_IFSET(CPU_FTR_TM)
> li r11,\trapnr
> std r11,_TRAP(r1)
> std r12,_CCR(r1)
> - std r3,ORIG_GPR3(r1)
> addi r10,r1,STACK_FRAME_OVERHEAD
> ld r11,exception_marker@toc(r2)
> std r11,-16(r10) /* "regshere" marker */
> @@ -278,7 +277,6 @@ END_BTB_FLUSH_SECTION
> std r10,_LINK(r1)
> std r11,_TRAP(r1)
> std r12,_CCR(r1)
> - std r3,ORIG_GPR3(r1)
> addi r10,r1,STACK_FRAME_OVERHEAD
> ld r11,exception_marker@toc(r2)
> std r11,-16(r10) /* "regshere" marker */
> diff --git a/arch/powerpc/kernel/interrupt.c b/arch/powerpc/kernel/interrupt.c
> index 46fd195ca659..1a2dec49f811 100644
> --- a/arch/powerpc/kernel/interrupt.c
> +++ b/arch/powerpc/kernel/interrupt.c
> @@ -29,6 +29,8 @@ notrace long system_call_exception(long r3, long r4, long r5,
> {
> syscall_fn f;
>
> + regs->orig_gpr3 = r3;
> +
> if (IS_ENABLED(CONFIG_PPC_IRQ_SOFT_MASK_DEBUG))
> BUG_ON(irq_soft_mask_return() != IRQS_ALL_DISABLED);
>
> --
> 2.25.0
>
>