[PATCH V2] ppc64/lv1call: Fix PS3 LV1 clobbering SRR

[Christophe Leroy]

Le 18/11/2025 à 18:49, René Rebe a écrit :
> For a while, likely since 6eaaf9de3599 ("powerpc/64s/interrupt: Check
> and fix srr_valid without crashing") booting a PS3 instantly yields:

Can you confirm the 'likely' ?

checkout 6eaaf9de3599 and confirm the bug is there.
checkout 6eaaf9de3599~ and confirm the bug is not there.

> 
> <4>SRR0 was: c0000000000971b4 should be: c0000000002d55c4
> <4>SRR1 was: 8000000000008032 should be: 8000000000008032
> 
> Fix LV1 HV clobbering SRR by srr_regs_clobbered() each lv1 call.
> Attribute srr_regs_clobbered __always_inline as used by modules.
> 
> Fixes: 6eaaf9de3599 ("powerpc/64s/interrupt: Check and fix srr_valid without crashing")
> Signed-off-by: René Rebe <rene at exactco.de>

Reviewed-by: Christophe Leroy <christophe.leroy at csgroup.eu>

> ---
> v2: use __always_inline, ppc64, Fixes:
> ---
>   arch/powerpc/include/asm/interrupt.h | 1 +
>   arch/powerpc/include/asm/lv1call.h   | 3 ++-
>   2 files changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/powerpc/include/asm/interrupt.h b/arch/powerpc/include/asm/interrupt.h
> index eb0e4a20b818..783c6f32a395 100644
> --- a/arch/powerpc/include/asm/interrupt.h
> +++ b/arch/powerpc/include/asm/interrupt.h
> @@ -106,6 +106,6 @@ static inline bool is_implicit_soft_masked(struct pt_regs *regs)
>   	return search_kernel_soft_mask_table(regs->nip);
>   }
>   
> -static inline void srr_regs_clobbered(void)
> +static __always_inline void srr_regs_clobbered(void)
>   {
>   	local_paca->srr_valid = 0;
>   	local_paca->hsrr_valid = 0;
> diff --git a/arch/powerpc/include/asm/lv1call.h b/arch/powerpc/include/asm/lv1call.h
> index ae70120953a8..48dd55a2b72e 100644
> --- a/arch/powerpc/include/asm/lv1call.h
> +++ b/arch/powerpc/include/asm/lv1call.h
> @@ -14,6 +14,7 @@
>   
>   #include <linux/types.h>
>   #include <linux/export.h>
> +#include <asm/interrupt.h>
>   
>   /* lv1 call declaration macros */
>   
> @@ -208,7 +209,7 @@
>   #define LV1_CALL(name, in, out, num)                               \
>     extern s64 _lv1_##name(LV1_##in##_IN_##out##_OUT_ARG_DECL);      \
>     static inline int lv1_##name(LV1_##in##_IN_##out##_OUT_ARG_DECL) \
> -    {return _lv1_##name(LV1_##in##_IN_##out##_OUT_ARGS);}
> +    {srr_regs_clobbered(); return _lv1_##name(LV1_##in##_IN_##out##_OUT_ARGS);}
>   #endif
>   
>   #endif /* !defined(__ASSEMBLER__) */