Subject: Re: [PATCH] powerpc/vdso: Fix incorrect CFI in gettimeofday.S

From: "Naveen N. Rao" <[email-masked]>
Date: Tue, 17 May 2022 13:03:21 +0530

Michael Ellerman wrote:
> 
> diff --git a/arch/powerpc/kernel/vdso/gettimeofday.S b/arch/powerpc/kernel/vdso/gettimeofday.S
> index eb9c81e1c218..0aee255e9cbb 100644
> --- a/arch/powerpc/kernel/vdso/gettimeofday.S
> +++ b/arch/powerpc/kernel/vdso/gettimeofday.S
> @@ -22,12 +22,15 @@
>  .macro cvdso_call funct call_time=0
>    .cfi_startproc
>  	PPC_STLU	r1, -PPC_MIN_STKFRM(r1)
> +  .cfi_adjust_cfa_offset PPC_MIN_STKFRM
>  	mflr		r0
> -  .cfi_register lr, r0
>  	PPC_STLU	r1, -PPC_MIN_STKFRM(r1)
> +  .cfi_adjust_cfa_offset PPC_MIN_STKFRM
>  	PPC_STL		r0, PPC_MIN_STKFRM + PPC_LR_STKOFF(r1)

<snip>

> @@ -46,6 +50,7 @@
>  	mtlr		r0
>    .cfi_restore lr
>  	addi		r1, r1, 2 * PPC_MIN_STKFRM
> +  .cfi_def_cfa_offset 0

Should this be .cfi_adjust_cfa_offset, given that we used that at the 
start of the function?

- Naveen