Pull pnfs/ore fixes from Boaz Harrosh:
"These are catastrophic fixes to the pnfs objects-layout that were just
discovered. They are also destined for @stable.
I have found these and worked on them at around RC1 time but
unfortunately went to the hospital for kidney stones and had a very
slow recovery. I refrained from sending them as is, before proper
testing, and surly I have found a bug just yesterday.
So now they are all well tested, and have my sign-off. Other then
fixing the problem at hand, and assuming there are no bugs at the new
code, there is low risk to any surrounding code. And in anyway they
affect only these paths that are now broken. That is RAID5 in pnfs
objects-layout code. It does also affect exofs (which was not broken)
but I have tested exofs and it is lower priority then objects-layout
because no one is using exofs, but objects-layout has lots of users."
* 'for-linus' of git://git.open-osd.org/linux-open-osd:
pnfs-obj: Fix __r4w_get_page when offset is beyond i_size
pnfs-obj: don't leak objio_state if ore_write/read fails
ore: Unlock r4w pages in exact reverse order of locking
ore: Remove support of partial IO request (NFS crash)
ore: Fix NFS crash by supporting any unaligned RAID IO
Pull UBIFS free space fix-up bugfix from Artem Bityutskiy:
"It's been reported already twice recently:
http://lists.infradead.org/pipermail/linux-mtd/2012-May/041408.htmlhttp://lists.infradead.org/pipermail/linux-mtd/2012-June/042422.html
and we finally have the fix. I am quite confident the fix is correct
because I could reproduce the problem with nandsim and verify the fix.
It was also verified by Iwo (the reporter).
I am also confident that this is OK to merge the fix so late because
this patch affects only the fixup functionality, which is not used by
most users."
* tag 'upstream-3.5-rc8' of git://git.infradead.org/linux-ubifs:
UBIFS: fix a bug in empty space fix-up
It is very common for the end of the file to be unaligned on
stripe size. But since we know it's beyond file's end then
the XOR should be preformed with all zeros.
Old code used to just read zeros out of the OSD devices, which is a great
waist. But what scares me more about this situation is that, we now have
pages attached to the file's mapping that are beyond i_size. I don't
like the kind of bugs this calls for.
Fix both birds, by returning a global zero_page, if offset is beyond
i_size.
TODO:
Change the API to ->__r4w_get_page() so a NULL can be
returned without being considered as error, since XOR API
treats NULL entries as zero_pages.
[Bug since 3.2. Should apply the same way to all Kernels since]
CC: Stable Tree <stable@kernel.org>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
The read-4-write pages are locked in address ascending order.
But where unlocked in a way easiest for coding. Fix that,
locks should be released in opposite order of locking, .i.e
descending address order.
I have not hit this dead-lock. It was found by inspecting the
dbug print-outs. I suspect there is an higher lock at caller that
protects us, but fix it regardless.
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Do to OOM situations the ore might fail to allocate all resources
needed for IO of the full request. If some progress was possible
it would proceed with a partial/short request, for the sake of
forward progress.
Since this crashes NFS-core and exofs is just fine without it just
remove this contraption, and fail.
TODO:
Support real forward progress with some reserved allocations
of resources, such as mem pools and/or bio_sets
[Bug since 3.2 Kernel]
CC: Stable Tree <stable@kernel.org>
CC: Benny Halevy <bhalevy@tonian.com>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
In RAID_5/6 We used to not permit an IO that it's end
byte is not stripe_size aligned and spans more than one stripe.
.i.e the caller must check if after submission the actual
transferred bytes is shorter, and would need to resubmit
a new IO with the remainder.
Exofs supports this, and NFS was supposed to support this
as well with it's short write mechanism. But late testing has
exposed a CRASH when this is used with none-RPC layout-drivers.
The change at NFS is deep and risky, in it's place the fix
at ORE to lift the limitation is actually clean and simple.
So here it is below.
The principal here is that in the case of unaligned IO on
both ends, beginning and end, we will send two read requests
one like old code, before the calculation of the first stripe,
and also a new site, before the calculation of the last stripe.
If any "boundary" is aligned or the complete IO is within a single
stripe. we do a single read like before.
The code is clean and simple by splitting the old _read_4_write
into 3 even parts:
1._read_4_write_first_stripe
2. _read_4_write_last_stripe
3. _read_4_write_execute
And calling 1+3 at the same place as before. 2+3 before last
stripe, and in the case of all in a single stripe then 1+2+3
is preformed additively.
Why did I not think of it before. Well I had a strike of
genius because I have stared at this code for 2 years, and did
not find this simple solution, til today. Not that I did not try.
This solution is much better for NFS than the previous supposedly
solution because the short write was dealt with out-of-band after
IO_done, which would cause for a seeky IO pattern where as in here
we execute in order. At both solutions we do 2 separate reads, only
here we do it within a single IO request. (And actually combine two
writes into a single submission)
NFS/exofs code need not change since the ORE API communicates the new
shorter length on return, what will happen is that this case would not
occur anymore.
hurray!!
[Stable this is an NFS bug since 3.2 Kernel should apply cleanly]
CC: Stable Tree <stable@kernel.org>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
UBIFS has a feature called "empty space fix-up" which is a quirk to work-around
limitations of dumb flasher programs. Namely, of those flashers that are unable
to skip NAND pages full of 0xFFs while flashing, resulting in empty space at
the end of half-filled eraseblocks to be unusable for UBIFS. This feature is
relatively new (introduced in v3.0).
The fix-up routine (fixup_free_space()) is executed only once at the very first
mount if the superblock has the 'space_fixup' flag set (can be done with -F
option of mkfs.ubifs). It basically reads all the UBIFS data and metadata and
writes it back to the same LEB. The routine assumes the image is pristine and
does not have anything in the journal.
There was a bug in 'fixup_free_space()' where it fixed up the log incorrectly.
All but one LEB of the log of a pristine file-system are empty. And one
contains just a commit start node. And 'fixup_free_space()' just unmapped this
LEB, which resulted in wiping the commit start node. As a result, some users
were unable to mount the file-system next time with the following symptom:
UBIFS error (pid 1): replay_log_leb: first log node at LEB 3:0 is not CS node
UBIFS error (pid 1): replay_log_leb: log error detected while replaying the log at LEB 3:0
The root-cause of this bug was that 'fixup_free_space()' wrongly assumed
that the beginning of empty space in the log head (c->lhead_offs) was known
on mount. However, it is not the case - it was always 0. UBIFS does not store
in it the master node and finds out by scanning the log on every mount.
The fix is simple - just pass commit start node size instead of 0 to
'fixup_leb()'.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@linux.intel.com>
Cc: stable@vger.kernel.org [v3.0+]
Reported-by: Iwo Mergler <Iwo.Mergler@netcommwireless.com>
Tested-by: Iwo Mergler <Iwo.Mergler@netcommwireless.com>
Reported-by: James Nute <newten82@gmail.com>
Pull CIFS fixes from Steve French.
* git://git.samba.org/sfrench/cifs-2.6:
cifs: always update the inode cache with the results from a FIND_*
cifs: when CONFIG_HIGHMEM is set, serialize the read/write kmaps
cifs: on CONFIG_HIGHMEM machines, limit the rsize/wsize to the kmap space
Initialise mid_q_entry before putting it on the pending queue
Pull a last-minute PM update from Rafael J. Wysocki:
"This renames CAP_EPOLLWAKEUP to CAP_BLOCK_SUSPEND to encourage future
reuse of the capability in question in related cases."
* tag 'pm-post-3.5-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
PM: Rename CAP_EPOLLWAKEUP to CAP_BLOCK_SUSPEND
As discussed in
http://thread.gmane.org/gmane.linux.kernel/1249726/focus=1288990,
the capability introduced in 4d7e30d989
to govern EPOLLWAKEUP seems misnamed: this capability is about governing
the ability to suspend the system, not using a particular API flag
(EPOLLWAKEUP). We should make the name of the capability more general
to encourage reuse in related cases. (Whether or not this capability
should also be used to govern the use of /sys/power/wake_lock is a
question that needs to be separately resolved.)
This patch renames the capability to CAP_BLOCK_SUSPEND. In order to ensure
that the old capability name doesn't make it out into the wild, could you
please apply and push up the tree to ensure that it is incorporated
for the 3.5 release.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
When we get back a FIND_FIRST/NEXT result, we have some info about the
dentry that we use to instantiate a new inode. We were ignoring and
discarding that info when we had an existing dentry in the cache.
Fix this by updating the inode in place when we find an existing dentry
and the uniqueid is the same.
Cc: <stable@vger.kernel.org> # .31.x
Reported-and-Tested-by: Andrew Bartlett <abartlet@samba.org>
Reported-by: Bill Robertson <bill_robertson@debortoli.com.au>
Reported-by: Dion Edwards <dion_edwards@debortoli.com.au>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Jian found that when he ran fsx on a 32 bit arch with a large wsize the
process and one of the bdi writeback kthreads would sometimes deadlock
with a stack trace like this:
crash> bt
PID: 2789 TASK: f02edaa0 CPU: 3 COMMAND: "fsx"
#0 [eed63cbc] schedule at c083c5b3
#1 [eed63d80] kmap_high at c0500ec8
#2 [eed63db0] cifs_async_writev at f7fabcd7 [cifs]
#3 [eed63df0] cifs_writepages at f7fb7f5c [cifs]
#4 [eed63e50] do_writepages at c04f3e32
#5 [eed63e54] __filemap_fdatawrite_range at c04e152a
#6 [eed63ea4] filemap_fdatawrite at c04e1b3e
#7 [eed63eb4] cifs_file_aio_write at f7fa111a [cifs]
#8 [eed63ecc] do_sync_write at c052d202
#9 [eed63f74] vfs_write at c052d4ee
#10 [eed63f94] sys_write at c052df4c
#11 [eed63fb0] ia32_sysenter_target at c0409a98
EAX: 00000004 EBX: 00000003 ECX: abd73b73 EDX: 012a65c6
DS: 007b ESI: 012a65c6 ES: 007b EDI: 00000000
SS: 007b ESP: bf8db178 EBP: bf8db1f8 GS: 0033
CS: 0073 EIP: 40000424 ERR: 00000004 EFLAGS: 00000246
Each task would kmap part of its address array before getting stuck, but
not enough to actually issue the write.
This patch fixes this by serializing the marshal_iov operations for
async reads and writes. The idea here is to ensure that cifs
aggressively tries to populate a request before attempting to fulfill
another one. As soon as all of the pages are kmapped for a request, then
we can unlock and allow another one to proceed.
There's no need to do this serialization on non-CONFIG_HIGHMEM arches
however, so optimize all of this out when CONFIG_HIGHMEM isn't set.
Cc: <stable@vger.kernel.org>
Reported-by: Jian Li <jiali@redhat.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
We currently rely on being able to kmap all of the pages in an async
read or write request. If you're on a machine that has CONFIG_HIGHMEM
set then that kmap space is limited, sometimes to as low as 512 slots.
With 512 slots, we can only support up to a 2M r/wsize, and that's
assuming that we can get our greedy little hands on all of them. There
are other users however, so it's possible we'll end up stuck with a
size that large.
Since we can't handle a rsize or wsize larger than that currently, cap
those options at the number of kmap slots we have. We could consider
capping it even lower, but we currently default to a max of 1M. Might as
well allow those luddites on 32 bit arches enough rope to hang
themselves.
A more robust fix would be to teach the send and receive routines how
to contend with an array of pages so we don't need to marshal up a kvec
array at all. That's a fairly significant overhaul though, so we'll need
this limit in place until that's ready.
Cc: <stable@vger.kernel.org>
Reported-by: Jian Li <jiali@redhat.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
A user reported a crash in cifs_demultiplex_thread() caused by an
incorrectly set mid_q_entry->callback() function. It appears that the
callback assignment made in cifs_call_async() was not flushed back to
memory suggesting that a memory barrier was required here. Changing the
code to make sure that the mid_q_entry structure was completely
initialised before it was added to the pending queue fixes the problem.
Signed-off-by: Sachin Prabhu <sprabhu@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Pull xfs regression fixes from Ben Myers:
- Really fix a cursor leak in xfs_alloc_ag_vextent_near
- Fix a performance regression related to doing allocation in
workqueues
- Prevent recursion in xfs_buf_iorequest which is causing stack
overflows
- Don't call xfs_bdstrat_cb in xfs_buf_iodone callbacks
* tag 'for-linus-v3.5-rc7' of git://oss.sgi.com/xfs/xfs:
xfs: do not call xfs_bdstrat_cb in xfs_buf_iodone_callbacks
xfs: prevent recursion in xfs_buf_iorequest
xfs: don't defer metadata allocation to the workqueue
xfs: really fix the cursor leak in xfs_alloc_ag_vextent_near
If a parent and child process open the two ends of a fifo, and the
child immediately exits, the parent may receive a SIGCHLD before its
open() returns. In that case, we need to make sure that open() will
return successfully after the SIGCHLD handler returns, instead of
throwing EINTR or being restarted. Otherwise, the restarted open()
would incorrectly wait for a second partner on the other end.
The following test demonstrates the EINTR that was wrongly thrown from
the parent’s open(). Change .sa_flags = 0 to .sa_flags = SA_RESTART
to see a deadlock instead, in which the restarted open() waits for a
second reader that will never come. (On my systems, this happens
pretty reliably within about 5 to 500 iterations. Others report that
it manages to loop ~forever sometimes; YMMV.)
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <fcntl.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#define CHECK(x) do if ((x) == -1) {perror(#x); abort();} while(0)
void handler(int signum) {}
int main()
{
struct sigaction act = {.sa_handler = handler, .sa_flags = 0};
CHECK(sigaction(SIGCHLD, &act, NULL));
CHECK(mknod("fifo", S_IFIFO | S_IRWXU, 0));
for (;;) {
int fd;
pid_t pid;
putc('.', stderr);
CHECK(pid = fork());
if (pid == 0) {
CHECK(fd = open("fifo", O_RDONLY));
_exit(0);
}
CHECK(fd = open("fifo", O_WRONLY));
CHECK(close(fd));
CHECK(waitpid(pid, NULL, 0));
}
}
This is what I suspect was causing the Git test suite to fail in
t9010-svn-fe.sh:
http://bugs.debian.org/678852
Signed-off-by: Anders Kaseorg <andersk@mit.edu>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
xfs_bdstrat_cb only adds a check for a shutdown filesystem over
xfs_buf_iorequest, but xfs_buf_iodone_callbacks just checked for a shut down
filesystem a little earlier. In addition the shutdown handling in
xfs_bdstrat_cb is not very suitable for this caller.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
If the b_iodone handler is run in calling context in xfs_buf_iorequest we
can run into a recursion where xfs_buf_iodone_callbacks keeps calling back
into xfs_buf_iorequest because an I/O error happened, which keeps calling
back into xfs_buf_iorequest. This chain will usually not take long
because the filesystem gets shut down because of log I/O errors, but even
over a short time it can cause stack overflows if run on the same context.
As a short term workaround make sure we always call the iodone handler in
workqueue context.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
Almost all metadata allocations come from shallow stack usage
situations. Avoid the overhead of switching the allocation to a
workqueue as we are not in danger of running out of stack when
making these allocations. Metadata allocations are already marked
through the args that are passed down, so this is trivial to do.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reported-by: Mel Gorman <mgorman@suse.de>
Tested-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: Ben Myers <bpm@sgi.com>
The current cursor is reallocated when retrying the allocation, so
the existing cursor needs to be destroyed in both the restart and
the failure cases.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Tested-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
Pull NFS client bugfixes from Trond Myklebust:
- Fix an NFSv4 mount regression
- Fix O_DIRECT list manipulation snafus
* tag 'nfs-for-3.5-4' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
NFSv4: Fix an NFSv4 mount regression
NFS: Fix list manipulation snafus in fs/nfs/direct.c
This can be trivially triggered from userspace by passing in something unexpected.
kernel BUG at fs/locks.c:1468!
invalid opcode: 0000 [#1] SMP
RIP: 0010:generic_setlease+0xc2/0x100
Call Trace:
__vfs_setlease+0x35/0x40
fcntl_setlease+0x76/0x150
sys_fcntl+0x1c6/0x810
system_call_fastpath+0x1a/0x1f
Signed-off-by: Dave Jones <davej@redhat.com>
Cc: stable@kernel.org # 3.2+
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 080399aaaf ("block: don't mark buffers beyond end of disk as
mapped") exposed a bug in __getblk_slow that causes mount to hang as it
loops infinitely waiting for a buffer that lies beyond the end of the
disk to become uptodate.
The problem was initially reported by Torsten Hilbrich here:
https://lkml.org/lkml/2012/6/18/54
and also reported independently here:
http://www.sysresccd.org/forums/viewtopic.php?f=13&t=4511
and then Richard W.M. Jones and Marcos Mello noted a few separate
bugzillas also associated with the same issue. This patch has been
confirmed to fix:
https://bugzilla.redhat.com/show_bug.cgi?id=835019
The main problem is here, in __getblk_slow:
for (;;) {
struct buffer_head * bh;
int ret;
bh = __find_get_block(bdev, block, size);
if (bh)
return bh;
ret = grow_buffers(bdev, block, size);
if (ret < 0)
return NULL;
if (ret == 0)
free_more_memory();
}
__find_get_block does not find the block, since it will not be marked as
mapped, and so grow_buffers is called to fill in the buffers for the
associated page. I believe the for (;;) loop is there primarily to
retry in the case of memory pressure keeping grow_buffers from
succeeding. However, we also continue to loop for other cases, like the
block lying beond the end of the disk. So, the fix I came up with is to
only loop when grow_buffers fails due to memory allocation issues
(return value of 0).
The attached patch was tested by myself, Torsten, and Rich, and was
found to resolve the problem in call cases.
Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Reported-and-Tested-by: Torsten Hilbrich <torsten.hilbrich@secunet.com>
Tested-by: Richard W.M. Jones <rjones@redhat.com>
Reviewed-by: Josh Boyer <jwboyer@redhat.com>
Cc: Stable <stable@vger.kernel.org> # 3.0+
[ Jens is on vacation, taking this directly - Linus ]
--
Stable Notes: this patch requires backport to 3.0, 3.2 and 3.3.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linus Torvalds
Boaz Harrosh
Artem Bityutskiy
Al Viro
Michael Kerrisk
Jeff Layton
Sachin Prabhu
Anders Kaseorg
Christoph Hellwig
Dave Chinner
Dave Jones
Jeff Moyer