On Wed, 6 Feb 2013 12:00:08 -0600 Steve French <smfrench@xxxxxxxxx> wrote: > Forwarding to the current cifs development mailing list > > > ---------- Forwarded message ---------- > From: <jiang.biao2@xxxxxxxxxx> > Date: Wed, Feb 6, 2013 at 12:26 AM > Subject: [PATCH] cifs: bugfix for unreclaimed writeback pages in > cifs_writev_requeue() > To: Steve French <sfrench@xxxxxxxxx>, linux-cifs-client@xxxxxxxxxxxxxxx > > > > This patch applies to the kernel version of linux-3.8-rc6. > > Pages get the PG_writeback flag set before cifs sends its request > to SMB server > in cifs_writepages(), if the SMB service goes down, cifs may try > to recommit the > writing requests in cifs_writev_requeue(). However, it does not > clean its PG_writeback > flag and relaimed the pages even if it fails again in > cifs_writev_requeue(), which > may lead to the hanging of the processes accessing the cifs > directory. This patch > just cleans the PG_writeback flags and reclaims the pages under > that circumstances. > > Steps to reproduce the bug(trying serveral times may trigger the issue): > 1.Write from cifs client continuously.(e.g dd if=/dev/zero of=<cifs file>) > 2.Stop SMB service from server.(e.g service smb stop) > 3.Wait for two minutes, and then start SMB service from > server.(e.g service smb start) > 4.The processes which are accessing cifs directory may hang up. > > Signed-off-by: Ouyang Maochun <ouyang.maochun@xxxxxxxxxx> > Signed-off-by: Jiang Yong <jian.yong5@xxxxxxxxxx> > Tested-by: Zhang Xianwei <zhang.xianwei8@xxxxxxxxxx> > Reviewed-by: Wang Liang <wang.liang82@xxxxxxxxxx> > Reviewed-by: Cai Qu <cai.qu@xxxxxxxxxx> > Reviewed-by: Jiang Biao <jiang.biao2@xxxxxxxxxx> > > diff -uprN linux-3.8-rc6/fs/cifs/cifssmb.c linux-3.8-rc6_new/fs/cifs/cifssmb.c > --- linux-3.8-rc6/fs/cifs/cifssmb.c 2013-02-01 09:08:14.000000000 +0800 > +++ linux-3.8-rc6_new/fs/cifs/cifssmb.c 2013-02-04 > 15:44:09.869254397 +0800 > @@ -1909,8 +1909,11 @@ cifs_writev_requeue(struct cifs_writedat > } while (rc == -EAGAIN); > > for (i = 0; i < wdata->nr_pages; i++) { > - if (rc != 0) > + if (rc != 0){ > SetPageError(wdata->pages[i]); > + end_page_writeback(wdata->pages[i]); > + page_cache_release(wdata->pages[i]); > + } > unlock_page(wdata->pages[i]); > } > > Patch looks correct to me. Nice catch. Reviewed-by: Jeff Layton <jlayton@xxxxxxxxxx> -- To unsubscribe from this list: send the line "unsubscribe linux-cifs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html