Re: [PATCH] powerpc/32: Remove redundant test in transfer_to_handler()

From	Christophe LEROY <christophe.leroy@c-s.fr>
Newsgroups	linux.kernel
Subject	Re: [PATCH] powerpc/32: Remove redundant test in transfer_to_handler()
Date	2017-04-18 13:30 +0200
Message-ID	<txzux-5A7-1@gated-at.bofh.it> (permalink)
References	<tw9Ca-1Db-3@gated-at.bofh.it>
Organization	linux.* mail to news gateway

Show all headers | View raw


Le 14/04/2017 à 15:31, Christophe Leroy a écrit :
> As stated in the comment on top of transfer_to_handler(),
> all callers set cr0.eq if the exception occurred in kernel mode
> (i.e. MSR:PR = 0)
>
> Therefore, it is not needed to do the test again

Indeed, all callers set cr0.eq as required .... except that some of
them just destroy it by inserting another test before calling 
transfer_to_handler().

So this patch cannot be applied as is at the time being.

Christophe

>
> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
> ---
>  arch/powerpc/kernel/entry_32.S | 1 -
>  1 file changed, 1 deletion(-)
>
> diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
> index a38600949f3a..0651a7438fa6 100644
> --- a/arch/powerpc/kernel/entry_32.S
> +++ b/arch/powerpc/kernel/entry_32.S
> @@ -141,7 +141,6 @@ transfer_to_handler:
>  	stw	r2,GPR2(r11)
>  	stw	r12,_NIP(r11)
>  	stw	r9,_MSR(r11)
> -	andi.	r2,r9,MSR_PR
>  	mfctr	r12
>  	mfspr	r2,SPRN_XER
>  	stw	r12,_CTR(r11)
>

Back to linux.kernel | Previous | Next — Previous in thread | Find similar | Unroll thread

Thread

[PATCH] powerpc/32: Remove redundant test in transfer_to_handler() Christophe Leroy <christophe.leroy@c-s.fr> - 2017-04-14 15:40 +0200
  Re: [PATCH] powerpc/32: Remove redundant test in  transfer_to_handler() Christophe LEROY <christophe.leroy@c-s.fr> - 2017-04-18 13:30 +0200

csiph-web