A tiny race between BAST and unlock message causes the NULL dereference.
A node sends an unlock request to master and receives a response. Before
processing the response it receives a BAST from the master. Since both
requests are processed by different threads it creates a race. While the
BAST is being processed, lock can get freed by unlock code.
This patch makes bast to return immediately if lock is found but unlock is
pending. The code should handle this race. We also have to fix master
node to skip sending BAST after receiving unlock message.
Below is the crash stack
BUG: unable to handle kernel NULL pointer dereference at 0000000000000048
IP: o2dlm_blocking_ast_wrapper+0xd/0x16
dlm_do_local_bast+0x8e/0x97 [ocfs2_dlm]
dlm_proxy_ast_handler+0x838/0x87e [ocfs2_dlm]
o2net_process_message+0x395/0x5b8 [ocfs2_nodemanager]
o2net_rx_until_empty+0x762/0x90d [ocfs2_nodemanager]
worker_thread+0x14d/0x1ed
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Srinivas Eeda <srinivas.eeda@oracle.com>
Reviewed-by: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Joseph Qi <joseph.qi@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[dan.carpenter@oracle.com: fix up some NULL dereference bugs]
Signed-off-by: Dong Fang <yp.fangdong@gmail.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Jeff Liu <jeff.liu@oracle.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add the domain name and the resource name in the mlogs.
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
* 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jlbec/ocfs2: (47 commits)
ocfs2: Silence a gcc warning.
ocfs2: Don't retry xattr set in case value extension fails.
ocfs2:dlm: avoid dlm->ast_lock lockres->spinlock dependency break
ocfs2: Reset xattr value size after xa_cleanup_value_truncate().
fs/ocfs2/dlm: Use kstrdup
fs/ocfs2/dlm: Drop memory allocation cast
Ocfs2: Optimize punching-hole code.
Ocfs2: Make ocfs2_find_cpos_for_left_leaf() public.
Ocfs2: Fix hole punching to correctly do CoW during cluster zeroing.
Ocfs2: Optimize ocfs2 truncate to use ocfs2_remove_btree_range() instead.
ocfs2: Block signals for mkdir/link/symlink/O_CREAT.
ocfs2: Wrap signal blocking in void functions.
ocfs2/dlm: Increase o2dlm lockres hash size
ocfs2: Make ocfs2_extend_trans() really extend.
ocfs2/trivial: Code cleanup for allocation reservation.
ocfs2: make ocfs2_adjust_resv_from_alloc simple.
ocfs2: Make nointr a default mount option
ocfs2/dlm: Make o2dlm domain join/leave messages KERN_NOTICE
o2net: log socket state changes
ocfs2: print node # when tcp fails
...
Currently we process a dirty lockres with the lockres->spinlock taken. While
during the process, we may need to lock on dlm->ast_lock. This breaks the
dependency of dlm->ast_lock(lock first) and lockres->spinlock(lock second).
This patch fixes the problem.
Since we can't release lockres->spinlock, we have to take dlm->ast_lock
just before taking the lockres->spinlock and release it after lockres->spinlock
is released. And use __dlm_queue_bast()/__dlm_queue_ast(), the nolock version,
in dlm_shuffle_lists(). There are no too many locks on a lockres, so there is no
performance harm.
Signed-off-by: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
Print the node number of a peer node if sending it a message failed.
Signed-off-by: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
The checking of lockres owner in dlm_update_lvb() is not inside spinlock
protection. I don't see problem in current call path of dlm_update_lvb().
But just for code robustness.
Signed-off-by: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
* remove asm/atomic.h inclusion from linux/utsname.h --
not needed after kref conversion
* remove linux/utsname.h inclusion from files which do not need it
NOTE: it looks like fs/binfmt_elf.c do not need utsname.h, however
due to some personality stuff it _is_ needed -- cowardly leave ELF-related
headers and files alone.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch cleans printed errors in dlm_proxy_ast_handler(). The errors now includes
the node number that sent the (b)ast. Also it reduces the number of endian swaps
of the cookie.
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
This patchset moves le*_add_cpu and be*_add_cpu functions from OCFS2 to core
header (1st), converts ext3 filesystem to this API (2nd) and replaces XFS
different named functions with new ones (3rd).
There are many places where these functions will be useful. Just look at:
grep -r 'cpu_to_[ble12346]*([ble12346]*_to_cpu.*[-+]' linux-src/ Patch for
ext3 is an example how conversions will probably look like.
This patch:
- move inline functions which add native byte order variable to
little/big endian variable to core header
* le16_add_cpu(__le16 *var, u16 val)
* le32_add_cpu(__le32 *var, u32 val)
* le64_add_cpu(__le64 *var, u64 val)
* be32_add_cpu(__be32 *var, u32 val)
- add for completeness:
* be16_add_cpu(__be16 *var, u16 val)
* be64_add_cpu(__be64 *var, u64 val)
Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Acked-by: Mark Fasheh <mark.fasheh@oracle.com>
Cc: David Chinner <dgc@sgi.com>
Cc: Timothy Shimmin <tes@sgi.com>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently o2net allows one handler function per message type. This
patch adds the ability to call another function to be called after
the handler has returned the message to the other node.
Handlers are now given the option of returning a context (in the form of a
void **) which will be passed back into the post message handler function.
Signed-off-by: Kurt Hackel <kurt.hackel@oracle.com>
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
The dlm encodes the node number and a sequence number in the lock cookie.
It also stores the cookie in the lockres in the big endian format to avoid
swapping 8 bytes on each lock request. The bug here was that it was assuming
the cookie to be in the cpu format when decoding it for printing the error
message. This patch swaps the bytes before the print.
Signed-off-by: Kurt Hackel <kurt.hackel@oracle.com>
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
An AST can be delivered via the network after a lock has been removed, so no
need to print an error when we see that.
Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
This patch converts the combination of list_del(A) and list_add(A, B) to
list_move(A, B) under fs/.
Cc: Ian Kent <raven@themaw.net>
Acked-by: Joel Becker <joel.becker@oracle.com>
Cc: Neil Brown <neilb@cse.unsw.edu.au>
Cc: Hans Reiser <reiserfs-dev@namesys.com>
Cc: Urban Widmark <urban@teststation.com>
Acked-by: David Howells <dhowells@redhat.com>
Acked-by: Mark Fasheh <mark.fasheh@oracle.com>
Signed-off-by: Akinobu Mita <mita@miraclelinux.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
A distributed lock manager built with the cluster file system use case
in mind. The OCFS2 dlm exposes a VMS style API, though things have
been simplified internally. The only lock levels implemented currently
are NLMODE, PRMODE and EXMODE.
Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
Signed-off-by: Kurt Hackel <kurt.hackel@oracle.com>
