Return-Path: Received: from mail-io0-f195.google.com ([209.85.223.195]:35251 "EHLO mail-io0-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751742AbcGSUe2 (ORCPT ); Tue, 19 Jul 2016 16:34:28 -0400 Received: by mail-io0-f195.google.com with SMTP id q83so2174592iod.2 for ; Tue, 19 Jul 2016 13:34:28 -0700 (PDT) From: Trond Myklebust To: linux-nfs@vger.kernel.org Subject: [PATCH v2 1/4] pNFS: Fix post-layoutget error handling in pnfs_update_layout() Date: Tue, 19 Jul 2016 16:33:54 -0400 Message-Id: <1468960437-21449-2-git-send-email-trond.myklebust@primarydata.com> In-Reply-To: <1468960437-21449-1-git-send-email-trond.myklebust@primarydata.com> References: <1468960437-21449-1-git-send-email-trond.myklebust@primarydata.com> Sender: linux-nfs-owner@vger.kernel.org List-ID: The non-retry error path is currently broken and ends up releasing the reference to the layout twice. It also can end up clearing the NFS_LAYOUT_FIRST_LAYOUTGET flag twice, causing a race. In addition, the retry path will fail to decrement the plh_outstanding counter. Fixes: 183d9e7b112aa ("pnfs: rework LAYOUTGET retry handling") Cc: stable@vger.kernel.org # 4.7 Signed-off-by: Trond Myklebust Reviewed-by: Jeff Layton --- fs/nfs/pnfs.c | 21 +++++++++++---------- 1 file changed, 11 insertions(+), 10 deletions(-) diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c index 0fbe734cc38c..563f131c9abe 100644 --- a/fs/nfs/pnfs.c +++ b/fs/nfs/pnfs.c @@ -1645,6 +1645,7 @@ lookup_again: lseg = send_layoutget(lo, ctx, &stateid, &arg, &timeout, gfp_flags); trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg, PNFS_UPDATE_LAYOUT_SEND_LAYOUTGET); + atomic_dec(&lo->plh_outstanding); if (IS_ERR(lseg)) { switch(PTR_ERR(lseg)) { case -ERECALLCONFLICT: @@ -1652,26 +1653,26 @@ lookup_again: lseg = NULL; /* Fallthrough */ case -EAGAIN: - pnfs_put_layout_hdr(lo); - if (first) - pnfs_clear_first_layoutget(lo); - if (lseg) { - trace_pnfs_update_layout(ino, pos, count, - iomode, lo, lseg, PNFS_UPDATE_LAYOUT_RETRY); - goto lookup_again; - } - /* Fallthrough */ + break; default: if (!nfs_error_is_fatal(PTR_ERR(lseg))) { pnfs_layout_clear_fail_bit(lo, pnfs_iomode_to_fail_bit(iomode)); lseg = NULL; } + goto out_put_layout_hdr; + } + if (lseg) { + if (first) + pnfs_clear_first_layoutget(lo); + trace_pnfs_update_layout(ino, pos, count, + iomode, lo, lseg, PNFS_UPDATE_LAYOUT_RETRY); + pnfs_put_layout_hdr(lo); + goto lookup_again; } } else { pnfs_layout_clear_fail_bit(lo, pnfs_iomode_to_fail_bit(iomode)); } - atomic_dec(&lo->plh_outstanding); out_put_layout_hdr: if (first) pnfs_clear_first_layoutget(lo); -- 2.7.4