From: Ben Kaduk Date: Sun, 24 Oct 2010 04:29:07 +0000 (-0400) Subject: FBSD: band-aid vnode locking in lookup X-Git-Tag: openafs-devel-1_7_1~1371 X-Git-Url: http://git.openafs.org/?p=openafs.git;a=commitdiff_plain;h=2f6be821ffeba607d4305586ad2c7ec4ba2b180c FBSD: band-aid vnode locking in lookup The lock order requires that we acquire vnode locks from the root towards the leaf. When looking up "..", this requires that we unlock the directory before locking the child, otherwise we are susceptible to deadlock. This is only a band-aid, as afs_vop_lookup should be rewritten. Change-Id: Ie99a677978370488f8edc7128014b89abc00a56c Reviewed-on: http://gerrit.openafs.org/3035 Tested-by: BuildBot Reviewed-by: Derrick Brashear --- diff --git a/src/afs/FBSD/osi_vnodeops.c b/src/afs/FBSD/osi_vnodeops.c index cbd94d7..5215642 100644 --- a/src/afs/FBSD/osi_vnodeops.c +++ b/src/afs/FBSD/osi_vnodeops.c @@ -531,7 +531,9 @@ afs_vop_lookup(ap) * we also always return the vnode locked. */ if (flags & ISDOTDOT) { + MA_VOP_UNLOCK(dvp, 0, p); ma_vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p); + ma_vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY, p); /* always return the child locked */ if (lockparent && (flags & ISLASTCN) && (error = ma_vn_lock(dvp, LK_EXCLUSIVE, p))) {