The end of the function is reachable both when host is and is not NULL.
A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)
// <smpl>
@r exists@
expression E,E1;
identifier f;
statement S1,S2,S3;
@@
if ((E == NULL && ...) || ...)
{
... when != if (...) S1 else S2
when != E = E1
* E->f
... when any
return ...;
}
else S3
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
I may have an explanation for the LSI 1068 HBA hangs provoked by ATA
pass-through commands, in particular by smartctl.
First, my version of the symptoms. On an LSI SAS1068E B3 HBA running
01.29.00.00 firmware, with SATA disks, and with smartd running, I'm seeing
occasional task, bus, and host resets, some of which lead to hard faults of
the HBA requiring a reboot. Abusively looping the smartctl command,
# while true; do smartctl -a /dev/sdb > /dev/null; done
dramatically increases the frequency of these failures to nearly one per
minute. A high IO load through the HBA while looping smartctl seems to
improve the chance of a full scsi host reset or a non-recoverable hang.
I reduced what smartctl was doing down to a simple test case which
causes the hang with a single IO when pointed at the sd interface. See
the code at the bottom of this e-mail. It uses an SG_IO ioctl to issue
a single pass-through ATA identify device command. If the buffer
userspace gives for the read data has certain alignments, the task is
issued to the HBA but the HBA fails to respond. If run against the sg
interface, neither the test code nor smartctl causes a hang.
sd and sg handle the SG_IO ioctl slightly differently. Unless you
specifically set a flag to do direct IO, sg passes a buffer of its own,
which is page-aligned, to the block layer and later copies the result
into the userspace buffer regardless of its alignment. sd, on the other
hand, always does direct IO unless the userspace buffer fails an
alignment test at block/blk-map.c line 57, in which case a page-aligned
buffer is created and used for the transfer.
The alignment test currently checks for word-alignment, the default
setup by scsi_lib.c; therefore, userspace buffers of almost any
alignment are given directly to the HBA as DMA targets. The LSI 1068
hardware doesn't seem to like at least a couple of the alignments which
cross a page boundary (see the test code below). Curiously, many
page-boundary-crossing alignments do work just fine.
So, either the hardware has an bug handling certain alignments or the
hardware has a stricter alignment requirement than the driver is
advertising. If stricter alignment is required, then in no case should
misaligned buffers from userspace be allowed through without being
bounced or at least causing an error to be returned.
It seems the mptsas driver could use blk_queue_dma_alignment() to advertise
a stricter alignment requirement. If it does, sd does the right thing and
bounces misaligned buffers (see block/blk-map.c line 57). The following
patch to 2.6.34-rc5 makes my symptoms go away. I'm sure this is the wrong
place for this code, but it gets my idea across.
Acked-by: "Desai, Kashyap" <Kashyap.Desai@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Adding DIF Type 2 protection support, as well as turning on 32 byte cdb's,
and setting the cdb length for > 16 byte in the SCSI_IO->control parameter.
Signed-off-by: Martin Petersen <martin.petersen@oracle.com>
Signed-off-by: Eric Moore <eric.moore@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
A driver needs to be ready to take an interrupt as soon as it registers
an interrupt handler. I noticed the following oops when testing kdump:
ipr: IBM Power RAID SCSI Device Driver version: 2.5.0 (February 11, 2010)
ibmvscsi 30000002: SRP_VERSION: 16.a
ibmvscsi 30000002: SRP_VERSION: 16.a
Unable to handle kernel paging request for data at address 0x00000000
...
pc: c000000004085e34: .tasklet_action+0xf4/0x1dc
...
c000000004086fe4 .__do_softirq+0x16c/0x2c0
c00000000403138c .call_do_softirq+0x14/0x24
c00000000400ee14 .do_softirq+0xa0/0x104
c00000000408690c .irq_exit+0x70/0xd0
c00000000400f190 .do_IRQ+0x214/0x2a8
c000000004004804 hardware_interrupt_entry+0x1c/0x98
--- Exception: 501 (Hardware Interrupt) at c00000000400c544 .raw_local_irq_restore+0x48/0x54
c00000000465d2a8 ._raw_spin_unlock_irqrestore+0x74/0xa0
c0000000040e7f00 .__setup_irq+0x2ec/0x3f0
c0000000040e8198 .request_threaded_irq+0x194/0x22c
c00000000446d854 .rpavscsi_init_crq_queue+0x284/0x3f0
c00000000446c764 .ibmvscsi_probe+0x688/0x710
c00000000402903c .vio_bus_probe+0x37c/0x3e4
c000000004403f10 .driver_probe_device+0xec/0x1b8
c000000004404088 .__driver_attach+0xac/0xf4
c000000004403184 .bus_for_each_dev+0x98/0x104
c000000004403c98 .driver_attach+0x40/0x60
c0000000044026f0 .bus_add_driver+0x154/0x324
c0000000044045d0 .driver_register+0xe8/0x1ac
c00000000402b2a8 .vio_register_driver+0x54/0x74
c000000004933ea4 .ibmvscsi_module_init+0x80/0xc0
c000000004009834 .do_one_initcall+0x98/0x1d8
c0000000049005b4 .kernel_init+0x27c/0x33c
c000000004031550 .kernel_thread+0x54/0x70
srp_task needs to be setup before request_irq. The patch below fixes the oops.
Signed-off-by: Anton Blanchard <anton@samba.org>
Acked-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6:
s2io: fixing DBG_PRINT() macro
ath9k: fix dma direction for map/unmap in ath_rx_tasklet
net: dev_forward_skb should call nf_reset
net sched: fix race in mirred device removal
tun: avoid BUG, dump packet on GSO errors
bonding: set device in RLB ARP packet handler
wimax/i2400m: Add PID & VID for Intel WiMAX 6250
ipv6: Don't add routes to ipv6 disabled interfaces.
net: Fix skb_copy_expand() handling of ->csum_start
net: Fix corruption of skb csum field in pskb_expand_head() of net/core/skbuff.c
macvtap: Limit packet queue length
ixgbe/igb: catch invalid VF settings
bnx2x: Advance a module version
bnx2x: Protect statistics ramrod and sequence number
bnx2x: Protect a SM state change
wireless: use netif_rx_ni in ieee80211_send_layer2_update
There are some drivers which may not set bdev->bd_dev. So make sure
it is non-NULL before dereferencing it.
Google-Bug-Id: 1773557
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Saying things like "sync failed" when a device does
not support barriers makes users slightly more worried than
they need to be; rather than talking about sync failures,
let's just state the barrier-based facts.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
I often get emails containing the "This should not happen!!" message,
conveniently trimmed to remove things like:
sd 0:0:0:0: [sda] Unhandled error code
sd 0:0:0:0: [sda] Result: hostbyte=DID_OK driverbyte=DRIVER_TIMEOUT
sd 0:0:0:0: [sda] CDB: Write(10): 2a 00 03 13 c9 70 00 00 28 00
end_request: I/O error, dev sda, sector 51628400
Aborting journal on device dm-0-8.
EXT4-fs error (device dm-0): ext4_journal_start_sb: Detected aborted journal
EXT4-fs (dm-0): Remounting filesystem read-only
I don't think there is any value to the verbosity if the reason is
due to a filesystem abort; it just obfuscates the root cause.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
ext4_get_blocks got renamed to ext4_map_blocks, but left stale
comments and a prototype littered around.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
When journaled quota options are not specified, we do writes
to quota files just in data=ordered mode. This actually causes
warnings from JBD2 about dirty journaled buffer because ext4_getblk
unconditionally treats a block allocated by it as metadata. Since
quota actually is filesystem metadata, the easiest way to get rid
of the warning is to always treat quota writes as metadata...
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Under heavy memory pressure we may hit out of memory
situation and as result kstrdup'ed options will not be
freed. Fix it.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
If the user attempts to make a non-extent-mapped file to be too large,
return EFBIG, but don't call ext4_std_err() which will end up marking
the file system as containing an error.
Thanks to Toshiyuki Okajima-san at Fujitsu for pointing this out.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
For some reason, today mballoc only allocates IOs which are exactly
stripe-sized on a stripe boundary. If you have a multiple (say, a
128k IO on a 64k stripe) you may end up unaligned.
It seems to me that a simple change to align stripe-multiple IOs
on stripe boundaries would be a very good idea, unless this breaks
some other mballoc heuristic for some reason...
Reported-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This patch is to be applied upon Christoph's "direct-io: move aio_complete
into ->end_io" patch. It adds iocb and result fields to struct ext4_io_end_t,
so that we can call aio_complete from ext4_end_io_nolock() after the extent
conversion has finished.
I have verified with Christoph's aio-dio test that used to fail after a few
runs on an original kernel but now succeeds on the patched kernel.
See http://thread.gmane.org/gmane.comp.file-systems.ext4/19659 for details.
Signed-off-by: Jiaying Zhang <jiayingz@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Filesystems with unwritten extent support must not complete an AIO request
until the transaction to convert the extent has been commited. That means
the aio_complete calls needs to be moved into the ->end_io callback so
that the filesystem can control when to call it exactly.
This makes a bit of a mess out of dio_complete and the ->end_io callback
prototype even more complicated.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Issue discard request in ext4_free_blocks() when ext4 has no journal and
is mounted with discard option.
Signed-off-by: Jiaying Zhang <jiayingz@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
__GFP_NOFAIL is going away, so add our own retry loop. Also add
jbd2__journal_start() and jbd2__journal_restart() which take a gfp
mask, so that file systems can optionally (re)start transaction
handles using GFP_KERNEL. If they do this, then they need to be
prepared to handle receiving an PTR_ERR(-ENOMEM) error, and be ready
to reflect that error up to userspace.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
We have experienced bitmap inconsistencies after crash during file
delete under heavy load. The crash is not file system related and I
the following patch in ext4_free_branches() fixes the recovery
problem.
If the transaction is restarted and there is a crash before the new
transaction is committed, then after recovery, the blocks that this
indirect block points to have been freed, but the indirect block
itself has not been freed and may still point to some of the free
blocks (because of the ext4_forget()).
So ext4_forget() should be called inside ext4_free_blocks() to avoid
this problem.
Signed-off-by: Amir Goldstein <amir73il@users.sf.net>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This allows us to grab any file system error messages by scraping
/var/log/messages. This will make it easy for us to do error analysis
across the very large number of machines as we deploy ext4 across the
fleet.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Save number of file system errors, and the time function name, line
number, block number, and inode number of the first and most recent
errors reported on the file system in the superblock.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
