public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Michal Simek <monstr@monstr.eu>
To: steve@digidescorp.com
Cc: microblaze-uclinux@itee.uq.edu.au, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] microblaze: nommu: Don't clobber R11 on syscalls
Date: Thu, 10 Dec 2009 08:31:51 +0100	[thread overview]
Message-ID: <4B20A3E7.70806@monstr.eu> (raw)
In-Reply-To: <1260400422-2805-1-git-send-email-steve@digidescorp.com>

Hi Steve,

steve@digidescorp.com wrote:
> The noMMU syscall trap has a bug that causes R11 to be zero on return to 
> userland. Remove the extra "save" of R11 responsible for the bug.

Can you please look if is even possible to remove that one line below?
( I mean line 212 - lwi	r11, r0, PER_CPU(KM) */
Interrupt rutine don't have it too. I am pretty sure that we can remove 
that line too.

Thanks for testing,
Michal


> 
> Signed-off-by: Steven J. Magnani <steve@digidescorp.com>
> ---
> diff -uprN a/arch/microblaze/kernel/entry-nommu.S b/arch/microblaze/kernel/entry-nommu.S
> --- a/arch/microblaze/kernel/entry-nommu.S	2009-12-09 17:05:11.000000000 -0600
> +++ b/arch/microblaze/kernel/entry-nommu.S	2009-12-09 17:07:31.000000000 -0600
> @@ -208,7 +208,6 @@ ENTRY(_user_exception)
>  	lwi	r1, r1, TS_THREAD_INFO		/* get the thread info */
>  	/* calculate kernel stack pointer */
>  	addik	r1, r1, THREAD_SIZE - PT_SIZE
> -	swi	r11, r0, PER_CPU(R11_SAVE)	/* temporarily save r11 */
>  	lwi	r11, r0, PER_CPU(KM)		/* load mode indicator */
>  2:
>  	swi	r11, r1, PT_MODE		/* store the mode */
> 


-- 
Michal Simek, Ing. (M.Eng)
w: www.monstr.eu p: +42-0-721842854
Maintainer of Linux kernel 2.6 Microblaze Linux - http://www.monstr.eu/fdt/
Microblaze U-BOOT custodian

      reply	other threads:[~2009-12-10  7:32 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-12-09 23:13 [PATCH] microblaze: nommu: Don't clobber R11 on syscalls steve
2009-12-10  7:31 ` Michal Simek [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=4B20A3E7.70806@monstr.eu \
    --to=monstr@monstr.eu \
    --cc=linux-kernel@vger.kernel.org \
    --cc=microblaze-uclinux@itee.uq.edu.au \
    --cc=steve@digidescorp.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox