From 68a564006a21ae59c7c51b4359e2e8efa42ae4af Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Tue, 18 Oct 2016 00:05:35 +0200 Subject: [PATCH] NFSv4.1: work around -Wmaybe-uninitialized warning A bugfix introduced a harmless gcc warning in nfs4_slot_seqid_in_use if we enable -Wmaybe-uninitialized again: fs/nfs/nfs4session.c:203:54: error: 'cur_seq' may be used uninitialized in this function [-Werror=maybe-uninitialized] gcc is not smart enough to conclude that the IS_ERR/PTR_ERR pair results in a nonzero return value here. Using PTR_ERR_OR_ZERO() instead makes this clear to the compiler. The warning originally did not appear in v4.8 as it was globally disabled, but the bugfix that introduced the warning got backported to stable kernels which again enable it, and this is now the only warning in the v4.7 builds. Fixes: e09c978aae5b ("NFSv4.1: Fix Oopsable condition in server callback races") Signed-off-by: Arnd Bergmann Cc: Trond Myklebust Signed-off-by: Anna Schumaker --- fs/nfs/nfs4session.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/fs/nfs/nfs4session.c b/fs/nfs/nfs4session.c index b62973045a3e..150c5a1879bf 100644 --- a/fs/nfs/nfs4session.c +++ b/fs/nfs/nfs4session.c @@ -178,12 +178,14 @@ static int nfs4_slot_get_seqid(struct nfs4_slot_table *tbl, u32 slotid, __must_hold(&tbl->slot_tbl_lock) { struct nfs4_slot *slot; + int ret; slot = nfs4_lookup_slot(tbl, slotid); - if (IS_ERR(slot)) - return PTR_ERR(slot); - *seq_nr = slot->seq_nr; - return 0; + ret = PTR_ERR_OR_ZERO(slot); + if (!ret) + *seq_nr = slot->seq_nr; + + return ret; } /* -- 2.20.1