From mboxrd@z Thu Jan 1 00:00:00 1970 From: Douglas Gilbert Subject: Re: [PATCH v5 0/4] [SCSI] sg: fix race condition in sg_open Date: Thu, 01 Aug 2013 01:01:11 -0400 Message-ID: <51F9EB97.7070305@interlog.com> References: <1374075246-22923-1-git-send-email-vaughan.cao@oracle.com> <1374468033-8947-1-git-send-email-vaughan.cao@oracle.com> <20130722170338.GA15824@logfs.org> Reply-To: dgilbert@interlog.com Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <20130722170338.GA15824@logfs.org> Sender: linux-kernel-owner@vger.kernel.org To: =?UTF-8?B?SsO2cm4gRW5nZWw=?= , Vaughan Cao , JBottomley@parallels.com Cc: linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: linux-scsi@vger.kernel.org On 13-07-22 01:03 PM, J=C3=B6rn Engel wrote: > On Mon, 22 July 2013 12:40:29 +0800, Vaughan Cao wrote: >> >> There is a race when open sg with O_EXCL flag. Also a race may happe= n between >> sg_open and sg_remove. >> >> Changes from v4: >> * [3/4] use ERR_PTR series instead of adding another parameter in = sg_add_sfp >> * [4/4] fix conflict for cherry-pick from v3. >> >> Changes from v3: >> * release o_sem in sg_release(), not in sg_remove_sfp(). >> * not set exclude with sfd_lock held. >> >> Vaughan Cao (4): >> [SCSI] sg: use rwsem to solve race during exclusive open >> [SCSI] sg: no need sg_open_exclusive_lock >> [SCSI] sg: checking sdp->detached isn't protected when open >> [SCSI] sg: push file descriptor list locking down to per-device >> locking >> >> drivers/scsi/sg.c | 178 +++++++++++++++++++++++++-----------------= ------------ >> 1 file changed, 83 insertions(+), 95 deletions(-) > > Patchset looks good to me, although I didn't test it on hardware yet. > Signed-off-by: Joern Engel > > James, care to pick this up? Acked-by: Douglas Gilbert Tested O_EXCL with multiple processes and threads; passed. sg driver prior to this patch had "leaky" O_EXCL logic according to the same test. Block device passed. James, could you clean this up: drivers/scsi/sg.c:242:6: warning: unused variable =E2=80=98res=E2=80= =99 [-Wunused-variable] Doug Gilbert