OpenAFS Master Repository branch, openafs-devel-1_7_x, updated. openafs-devel-1_7_14-1-g8f18ee0
Gerrit Code Review
gerrit@openafs.org
Fri, 1 Jun 2012 17:26:13 -0700 (PDT)
The following commit has been merged in the openafs-devel-1_7_x branch:
commit 8f18ee0c1eed4bd3aa83bfae419e93fbca6ab62d
Author: Jeffrey Altman <jaltman@your-file-system.com>
Date: Thu May 24 04:57:19 2012 -0400
Windows: Avoid deadlock on VolumeCB->VolumeLock
AFSPrimaryVolumeWorkerThread() holds VolumeCB->VolumeLock SHARED
across the call to AFSCleanupFcb() -> CcPurgeCacheSection().
If a filter driver such as Sophos (savonaccessfilter.sys ->
savonaccesscontrol.sys) triggers an AFSCreate() in response to
the cache section being purged that will force the evaluation of
the file path by AFSLocateNameEntry(). If the path contains a
mount point that requires validation, AFSBuildMountPointTarget()
is called which in turn required the VolumeCB->VolumeLock EXCL.
AFSBuildMountPointTarget() only requires the VolumeCB->VolumeLock
if the VolumeCB->RootFcb == NULL. That should only be true if
the VolumeCB was allocated by AFSInitVolume() or under very rare
race conditions.
This patchset refactors AFSInitVolume() to ensure that it holds
an extra VolumeCB->VolumeReferenceCount reference. This reference
is used to assist in the refactoring of AFSBuildRootVolume() and
AFSBuildMountPointTarget() to avoid races with volume root object
invalidation as well as permitting the VolumeCB->VolumeLock to
be ignored in the common case.
Avoiding the acquisition of VolumeCB->VolumeLock during mount
point target evaluation has the additional benefit of reducing
lock contention during path evaluation.
FIXES 130812
Reviewed-on: http://gerrit.openafs.org/7474
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Peter Scott <pscott@kerneldrivers.com>
Reviewed-by: Jeffrey Altman <jaltman@secure-endpoints.com>
Tested-by: Jeffrey Altman <jaltman@secure-endpoints.com>
(cherry picked from commit 06a602bfd40661ef89b3d6b39dd8574015a15b92)
Change-Id: I817dc51ae57adb145cbd9078c86f9df12b31fd28
Reviewed-on: http://gerrit.openafs.org/7507
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Jeffrey Altman <jaltman@secure-endpoints.com>
src/WINNT/afsrdr/kernel/lib/AFSFcbSupport.cpp | 6 +-
src/WINNT/afsrdr/kernel/lib/AFSGeneric.cpp | 5 +
src/WINNT/afsrdr/kernel/lib/AFSNameSupport.cpp | 112 ++++++++++++++----------
3 files changed, 74 insertions(+), 49 deletions(-)
--
OpenAFS Master Repository