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  1. 07 6月, 2018 1 次提交
  3. 03 6月, 2018 1 次提交
  5. 01 6月, 2018 6 次提交
  7. 31 5月, 2018 1 次提交
  9. 28 5月, 2018 1 次提交
  11. 13 4月, 2018 2 次提交
  13. 03 4月, 2018 2 次提交
  15. 02 4月, 2018 1 次提交
  17. 25 1月, 2018 1 次提交
  19. 03 5月, 2017 1 次提交
    • R
      CIFS: fix oplock break deadlocks · 3998e6b8
      由 Rabin Vincent 提交于 
      When the final cifsFileInfo_put() is called from cifsiod and an oplock
break work is queued, lockdep complains loudly:

 =============================================
 [ INFO: possible recursive locking detected ]
 4.11.0+ #21 Not tainted
 ---------------------------------------------
 kworker/0:2/78 is trying to acquire lock:
  ("cifsiod"){++++.+}, at: flush_work+0x215/0x350

 but task is already holding lock:
  ("cifsiod"){++++.+}, at: process_one_work+0x255/0x8e0

 other info that might help us debug this:
  Possible unsafe locking scenario:

        CPU0
        ----
   lock("cifsiod");
   lock("cifsiod");

  *** DEADLOCK ***

  May be due to missing lock nesting notation

 2 locks held by kworker/0:2/78:
  #0:  ("cifsiod"){++++.+}, at: process_one_work+0x255/0x8e0
  #1:  ((&wdata->work)){+.+...}, at: process_one_work+0x255/0x8e0

 stack backtrace:
 CPU: 0 PID: 78 Comm: kworker/0:2 Not tainted 4.11.0+ #21
 Workqueue: cifsiod cifs_writev_complete
 Call Trace:
  dump_stack+0x85/0xc2
  __lock_acquire+0x17dd/0x2260
  ? match_held_lock+0x20/0x2b0
  ? trace_hardirqs_off_caller+0x86/0x130
  ? mark_lock+0xa6/0x920
  lock_acquire+0xcc/0x260
  ? lock_acquire+0xcc/0x260
  ? flush_work+0x215/0x350
  flush_work+0x236/0x350
  ? flush_work+0x215/0x350
  ? destroy_worker+0x170/0x170
  __cancel_work_timer+0x17d/0x210
  ? ___preempt_schedule+0x16/0x18
  cancel_work_sync+0x10/0x20
  cifsFileInfo_put+0x338/0x7f0
  cifs_writedata_release+0x2a/0x40
  ? cifs_writedata_release+0x2a/0x40
  cifs_writev_complete+0x29d/0x850
  ? preempt_count_sub+0x18/0xd0
  process_one_work+0x304/0x8e0
  worker_thread+0x9b/0x6a0
  kthread+0x1b2/0x200
  ? process_one_work+0x8e0/0x8e0
  ? kthread_create_on_node+0x40/0x40
  ret_from_fork+0x31/0x40

This is a real warning.  Since the oplock is queued on the same
workqueue this can deadlock if there is only one worker thread active
for the workqueue (which will be the case during memory pressure when
the rescuer thread is handling it).

Furthermore, there is at least one other kind of hang possible due to
the oplock break handling if there is only worker.  (This can be
reproduced without introducing memory pressure by having passing 1 for
the max_active parameter of cifsiod.) cifs_oplock_break() can wait
indefintely in the filemap_fdatawait() while the cifs_writev_complete()
work is blocked:

 sysrq: SysRq : Show Blocked State
   task                        PC stack   pid father
 kworker/0:1     D    0    16      2 0x00000000
 Workqueue: cifsiod cifs_oplock_break
 Call Trace:
  __schedule+0x562/0xf40
  ? mark_held_locks+0x4a/0xb0
  schedule+0x57/0xe0
  io_schedule+0x21/0x50
  wait_on_page_bit+0x143/0x190
  ? add_to_page_cache_lru+0x150/0x150
  __filemap_fdatawait_range+0x134/0x190
  ? do_writepages+0x51/0x70
  filemap_fdatawait_range+0x14/0x30
  filemap_fdatawait+0x3b/0x40
  cifs_oplock_break+0x651/0x710
  ? preempt_count_sub+0x18/0xd0
  process_one_work+0x304/0x8e0
  worker_thread+0x9b/0x6a0
  kthread+0x1b2/0x200
  ? process_one_work+0x8e0/0x8e0
  ? kthread_create_on_node+0x40/0x40
  ret_from_fork+0x31/0x40
 dd              D    0   683    171 0x00000000
 Call Trace:
  __schedule+0x562/0xf40
  ? mark_held_locks+0x29/0xb0
  schedule+0x57/0xe0
  io_schedule+0x21/0x50
  wait_on_page_bit+0x143/0x190
  ? add_to_page_cache_lru+0x150/0x150
  __filemap_fdatawait_range+0x134/0x190
  ? do_writepages+0x51/0x70
  filemap_fdatawait_range+0x14/0x30
  filemap_fdatawait+0x3b/0x40
  filemap_write_and_wait+0x4e/0x70
  cifs_flush+0x6a/0xb0
  filp_close+0x52/0xa0
  __close_fd+0xdc/0x150
  SyS_close+0x33/0x60
  entry_SYSCALL_64_fastpath+0x1f/0xbe

 Showing all locks held in the system:
 2 locks held by kworker/0:1/16:
  #0:  ("cifsiod"){.+.+.+}, at: process_one_work+0x255/0x8e0
  #1:  ((&cfile->oplock_break)){+.+.+.}, at: process_one_work+0x255/0x8e0

 Showing busy workqueues and worker pools:
 workqueue cifsiod: flags=0xc
   pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/1
     in-flight: 16:cifs_oplock_break
     delayed: cifs_writev_complete, cifs_echo_request
 pool 0: cpus=0 node=0 flags=0x0 nice=0 hung=0s workers=3 idle: 750 3

Fix these problems by creating a a new workqueue (with a rescuer) for
the oplock break work.
Signed-off-by: NRabin Vincent <rabinv@axis.com>
Signed-off-by: NSteve French <smfrench@gmail.com>
CC: Stable <stable@vger.kernel.org>
      3998e6b8
  21. 07 4月, 2017 1 次提交
    • S
      Handle mismatched open calls · 38bd4906
      由 Sachin Prabhu 提交于 
      A signal can interrupt a SendReceive call which result in incoming
responses to the call being ignored. This is a problem for calls such as
open which results in the successful response being ignored. This
results in an open file resource on the server.

The patch looks into responses which were cancelled after being sent and
in case of successful open closes the open fids.

For this patch, the check is only done in SendReceive2()

RH-bz: 1403319
Signed-off-by: NSachin Prabhu <sprabhu@redhat.com>
Reviewed-by: NPavel Shilovsky <pshilov@microsoft.com>
Cc: Stable <stable@vger.kernel.org>
      38bd4906
  23. 02 2月, 2017 1 次提交
  25. 13 10月, 2016 1 次提交
  27. 15 1月, 2016 1 次提交
  29. 16 4月, 2015 1 次提交
  31. 01 4月, 2015 1 次提交
  33. 15 12月, 2014 1 次提交
    • S
      Convert MessageID in smb2_hdr to LE · 9235d098
      由 Sachin Prabhu 提交于 
      We have encountered failures when When testing smb2 mounts on ppc64
machines when using both Samba as well as Windows 2012.

On poking around, the problem was determined to be caused by the
high endian MessageID passed in the header for smb2. On checking the
corresponding MID for smb1 is converted to LE before being sent on the
wire.

We have tested this patch successfully on a ppc64 machine.
Signed-off-by: NSachin Prabhu <sprabhu@redhat.com>
      9235d098
  35. 11 12月, 2014 1 次提交
  37. 17 10月, 2014 1 次提交
  39. 16 8月, 2014 1 次提交
    • S
      [CIFS] Workaround MacOS server problem with SMB2.1 write · 754789a1
      由 Steve French 提交于 
       response

Writes fail to Mac servers with SMB2.1 mounts (works with cifs though) due
to them sending an incorrect RFC1001 length for the SMB2.1 Write response.
Workaround this problem. MacOS server sends a write response with 3 bytes
of pad beyond the end of the SMB itself.  The RFC1001 length is 3 bytes
more than the sum of the SMB2.1 header length + the write reponse.

Incorporate feedback from Jeff and JRA to allow servers to send
a tcp frame that is even more than three bytes too long
(ie much longer than the SMB2/SMB3 request that it contains) but
we do log it once now. In the earlier version of the patch I had
limited how far off the length field could be before we fail the request.
Signed-off-by: NSteve French <smfrench@gmail.com>
      754789a1
  41. 03 8月, 2014 1 次提交
  43. 17 4月, 2014 1 次提交
    • S
      cifs: Wait for writebacks to complete before attempting write. · c11f1df5
      由 Sachin Prabhu 提交于 
      Problem reported in Red Hat bz 1040329 for strict writes where we cache
only when we hold oplock and write direct to the server when we don't.

When we receive an oplock break, we first change the oplock value for
the inode in cifsInodeInfo->oplock to indicate that we no longer hold
the oplock before we enqueue a task to flush changes to the backing
device. Once we have completed flushing the changes, we return the
oplock to the server.

There are 2 ways here where we can have data corruption
1) While we flush changes to the backing device as part of the oplock
break, we can have processes write to the file. These writes check for
the oplock, find none and attempt to write directly to the server.
These direct writes made while we are flushing from cache could be
overwritten by data being flushed from the cache causing data
corruption.
2) While a thread runs in cifs_strict_writev, the machine could receive
and process an oplock break after the thread has checked the oplock and
found that it allows us to cache and before we have made changes to the
cache. In that case, we end up with a dirty page in cache when we
shouldn't have any. This will be flushed later and will overwrite all
subsequent writes to the part of the file represented by this page.

Before making any writes to the server, we need to confirm that we are
not in the process of flushing data to the server and if we are, we
should wait until the process is complete before we attempt the write.
We should also wait for existing writes to complete before we process
an oplock break request which changes oplock values.

We add a version specific  downgrade_oplock() operation to allow for
differences in the oplock values set for the different smb versions.

Cc: stable@vger.kernel.org
Signed-off-by: NSachin Prabhu <sprabhu@redhat.com>
Reviewed-by: NJeff Layton <jlayton@redhat.com>
Reviewed-by: NPavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: NSteve French <smfrench@gmail.com>
      c11f1df5
  45. 10 9月, 2013 2 次提交
  47. 09 9月, 2013 4 次提交
  49. 27 6月, 2013 1 次提交
    • S
      SMB2 FSCTL and IOCTL worker function · 4a72dafa
      由 Steve French 提交于 
      This worker function is needed to send SMB2 fsctl
(and ioctl) requests including:

validating negotiation info (secure negotiate)
querying the servers network interfaces
copy offload (refcopy)

Followon patches for the above three will use this.
This patch also does general validation of the response.

In the future, as David Disseldorp notes, for the copychunk ioctl
case, we will want to enhance the response processing to allow
returning the chunk request limits to the caller (even
though the server returns an error, in that case we would
return data that the caller could use - see 2.2.32.1).

See MS-SMB2 Section 2.2.31 for more details on format of fsctl.
Acked-by: NPavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: NSteve French <smfrench@gmail.com>
      4a72dafa
  51. 05 5月, 2013 1 次提交
    • J
      [CIFS] cifs: Rename cERROR and cFYI to cifs_dbg · f96637be
      由 Joe Perches 提交于 
      It's not obvious from reading the macro names that these macros
are for debugging.  Convert the names to a single more typical
kernel style cifs_dbg macro.

	cERROR(1, ...)   -> cifs_dbg(VFS, ...)
	cFYI(1, ...)     -> cifs_dbg(FYI, ...)
	cFYI(DBG2, ...)  -> cifs_dbg(NOISY, ...)

Move the terminating format newline from the macro to the call site.

Add CONFIG_CIFS_DEBUG function cifs_vfs_err to emit the
"CIFS VFS: " prefix for VFS messages.

Size is reduced ~ 1% when CONFIG_CIFS_DEBUG is set (default y)

$ size fs/cifs/cifs.ko*
   text    data     bss     dec     hex filename
 265245	   2525	    132	 267902	  4167e	fs/cifs/cifs.ko.new
 268359    2525     132  271016   422a8 fs/cifs/cifs.ko.old

Other miscellaneous changes around these conversions:

o Miscellaneous typo fixes
o Add terminating \n's to almost all formats and remove them
  from the macros to be more kernel style like.  A few formats
  previously had defective \n's
o Remove unnecessary OOM messages as kmalloc() calls dump_stack
o Coalesce formats to make grep easier,
  added missing spaces when coalescing formats
o Use %s, __func__ instead of embedded function name
o Removed unnecessary "cifs: " prefixes
o Convert kzalloc with multiply to kcalloc
o Remove unused cifswarn macro
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <smfrench@gmail.com>
      f96637be
  53. 25 9月, 2012 3 次提交