From: "Reddy, Sreekanth" <Sreekanth.Reddy@lsi.com>
To: Alexey Khoroshilov <khoroshilov@ispras.ru>,
"James E.J. Bottomley" <JBottomley@parallels.com>
Cc: "linux-scsi@vger.kernel.org" <linux-scsi@vger.kernel.org>,
"Nandigama, Nagalakshmi" <Nagalakshmi.Nandigama@lsi.com>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"ldv-project@ispras.ru" <ldv-project@ispras.ru>
Subject: RE: [PATCH v2] [SCSI] mpt2sas: fix double mutex lock in NON_BLOCKING state
Date: Wed, 29 Aug 2012 15:48:06 +0530 [thread overview]
Message-ID: <DCD177647606E9419ED923E0C8C4AA7223E20ADBF8@inbmail02.lsi.com> (raw)
In-Reply-To: <1346164683-9315-1-git-send-email-khoroshilov@ispras.ru>
James,
This patch seem to be fine. Please consider this patch as Acked-by: "Sreekanth Reddy" <sreekanth.reddy@lsi.com>
Regards,
Sreekanth.
> -----Original Message-----
> From: Alexey Khoroshilov [mailto:khoroshilov@ispras.ru]
> Sent: Tuesday, August 28, 2012 8:08 PM
> To: James E.J. Bottomley
> Cc: Alexey Khoroshilov; linux-scsi@vger.kernel.org; Nandigama,
> Nagalakshmi; Reddy, Sreekanth; linux-kernel@vger.kernel.org; ldv-
> project@ispras.ru
> Subject: [PATCH v2] [SCSI] mpt2sas: fix double mutex lock in
> NON_BLOCKING state
>
> If state is NON_BLOCKING and mutex_trylock is succeed,
> the control flow goes to mutex_lock_interruptible() that is a deadlock.
>
> The previous version of the patch becomes obsolete after
> code movement in commit 913809f6.
>
> Found by Linux Driver Verification project (linuxtesting.org).
>
> Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
> ---
> drivers/scsi/mpt2sas/mpt2sas_ctl.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/scsi/mpt2sas/mpt2sas_ctl.c
> b/drivers/scsi/mpt2sas/mpt2sas_ctl.c
> index 49bdd2d..d29ea56 100644
> --- a/drivers/scsi/mpt2sas/mpt2sas_ctl.c
> +++ b/drivers/scsi/mpt2sas/mpt2sas_ctl.c
> @@ -2181,8 +2181,10 @@ _ctl_ioctl_main(struct file *file, unsigned int
> cmd, void __user *arg,
> return -EAGAIN;
>
> state = (file->f_flags & O_NONBLOCK) ? NON_BLOCKING : BLOCKING;
> - if (state == NON_BLOCKING && !mutex_trylock(&ioc-
> >ctl_cmds.mutex))
> - return -EAGAIN;
> + if (state == NON_BLOCKING) {
> + if (!mutex_trylock(&ioc->ctl_cmds.mutex))
> + return -EAGAIN;
> + }
> else if (mutex_lock_interruptible(&ioc->ctl_cmds.mutex))
> return -ERESTARTSYS;
>
> --
> 1.7.9.5
prev parent reply other threads:[~2012-08-29 10:18 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-08-28 14:38 [PATCH v2] [SCSI] mpt2sas: fix double mutex lock in NON_BLOCKING state Alexey Khoroshilov
2012-08-29 10:18 ` Reddy, Sreekanth [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=DCD177647606E9419ED923E0C8C4AA7223E20ADBF8@inbmail02.lsi.com \
--to=sreekanth.reddy@lsi.com \
--cc=JBottomley@parallels.com \
--cc=Nagalakshmi.Nandigama@lsi.com \
--cc=khoroshilov@ispras.ru \
--cc=ldv-project@ispras.ru \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-scsi@vger.kernel.org \
/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;
as well as URLs for NNTP newsgroup(s).