linux.git/drivers/block, branch v5.3-rc4

loop: set PF_MEMALLOC_NOIO for the worker thread

2019-08-08T16:12:21+00:00

A deadlock with this stacktrace was observed.

The loop thread does a GFP_KERNEL allocation, it calls into dm-bufio
shrinker and the shrinker depends on I/O completion in the dm-bufio
subsystem.

In order to fix the deadlock (and other similar ones), we set the flag
PF_MEMALLOC_NOIO at loop thread entry.

PID: 474    TASK: ffff8813e11f4600  CPU: 10  COMMAND: "kswapd0"
   #0 [ffff8813dedfb938] __schedule at ffffffff8173f405
   #1 [ffff8813dedfb990] schedule at ffffffff8173fa27
   #2 [ffff8813dedfb9b0] schedule_timeout at ffffffff81742fec
   #3 [ffff8813dedfba60] io_schedule_timeout at ffffffff8173f186
   #4 [ffff8813dedfbaa0] bit_wait_io at ffffffff8174034f
   #5 [ffff8813dedfbac0] __wait_on_bit at ffffffff8173fec8
   #6 [ffff8813dedfbb10] out_of_line_wait_on_bit at ffffffff8173ff81
   #7 [ffff8813dedfbb90] __make_buffer_clean at ffffffffa038736f [dm_bufio]
   #8 [ffff8813dedfbbb0] __try_evict_buffer at ffffffffa0387bb8 [dm_bufio]
   #9 [ffff8813dedfbbd0] dm_bufio_shrink_scan at ffffffffa0387cc3 [dm_bufio]
  #10 [ffff8813dedfbc40] shrink_slab at ffffffff811a87ce
  #11 [ffff8813dedfbd30] shrink_zone at ffffffff811ad778
  #12 [ffff8813dedfbdc0] kswapd at ffffffff811ae92f
  #13 [ffff8813dedfbec0] kthread at ffffffff810a8428
  #14 [ffff8813dedfbf50] ret_from_fork at ffffffff81745242

  PID: 14127  TASK: ffff881455749c00  CPU: 11  COMMAND: "loop1"
   #0 [ffff88272f5af228] __schedule at ffffffff8173f405
   #1 [ffff88272f5af280] schedule at ffffffff8173fa27
   #2 [ffff88272f5af2a0] schedule_preempt_disabled at ffffffff8173fd5e
   #3 [ffff88272f5af2b0] __mutex_lock_slowpath at ffffffff81741fb5
   #4 [ffff88272f5af330] mutex_lock at ffffffff81742133
   #5 [ffff88272f5af350] dm_bufio_shrink_count at ffffffffa03865f9 [dm_bufio]
   #6 [ffff88272f5af380] shrink_slab at ffffffff811a86bd
   #7 [ffff88272f5af470] shrink_zone at ffffffff811ad778
   #8 [ffff88272f5af500] do_try_to_free_pages at ffffffff811adb34
   #9 [ffff88272f5af590] try_to_free_pages at ffffffff811adef8
  #10 [ffff88272f5af610] __alloc_pages_nodemask at ffffffff811a09c3
  #11 [ffff88272f5af710] alloc_pages_current at ffffffff811e8b71
  #12 [ffff88272f5af760] new_slab at ffffffff811f4523
  #13 [ffff88272f5af7b0] __slab_alloc at ffffffff8173a1b5
  #14 [ffff88272f5af880] kmem_cache_alloc at ffffffff811f484b
  #15 [ffff88272f5af8d0] do_blockdev_direct_IO at ffffffff812535b3
  #16 [ffff88272f5afb00] __blockdev_direct_IO at ffffffff81255dc3
  #17 [ffff88272f5afb30] xfs_vm_direct_IO at ffffffffa01fe3fc [xfs]
  #18 [ffff88272f5afb90] generic_file_read_iter at ffffffff81198994
  #19 [ffff88272f5afc50] __dta_xfs_file_read_iter_2398 at ffffffffa020c970 [xfs]
  #20 [ffff88272f5afcc0] lo_rw_aio at ffffffffa0377042 [loop]
  #21 [ffff88272f5afd70] loop_queue_work at ffffffffa0377c3b [loop]
  #22 [ffff88272f5afe60] kthread_worker_fn at ffffffff810a8a0c
  #23 [ffff88272f5afec0] kthread at ffffffff810a8428
  #24 [ffff88272f5aff50] ret_from_fork at ffffffff81745242

Signed-off-by: Mikulas Patocka 
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe

block: aoe: Fix kernel crash due to atomic sleep when exiting

2019-08-08T13:29:02+00:00

Since commit 3582dd291788 ("aoe: convert aoeblk to blk-mq"), aoedev_downdev
has had the possibility of sleeping and causing the following crash.

BUG: scheduling while atomic: rmmod/2242/0x00000003
Modules linked in: aoe
Preemption disabled at:
[] flush+0x95/0x4a0 [aoe]
CPU: 7 PID: 2242 Comm: rmmod Tainted: G          I       5.2.3 #1
Hardware name: Intel Corporation S5520HC/S5520HC, BIOS S5500.86B.01.10.0025.030220091519 03/02/2009
Call Trace:
 dump_stack+0x4f/0x6a
 ? flush+0x95/0x4a0 [aoe]
 __schedule_bug.cold+0x44/0x54
 __schedule+0x44f/0x680
 schedule+0x44/0xd0
 blk_mq_freeze_queue_wait+0x46/0xb0
 ? wait_woken+0x80/0x80
 blk_mq_freeze_queue+0x1b/0x20
 aoedev_downdev+0x111/0x160 [aoe]
 flush+0xff/0x4a0 [aoe]
 aoedev_exit+0x23/0x30 [aoe]
 aoe_exit+0x35/0x948 [aoe]
 __se_sys_delete_module+0x183/0x210
 __x64_sys_delete_module+0x16/0x20
 do_syscall_64+0x4d/0x130
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7f24e0043b07
Code: 73 01 c3 48 8b 0d 89 73 0b 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f
1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 b0 00 00 00 0f 05 <48> 3d 01 f0 ff
ff 73 01 c3 48 8b 0d 59 73 0b 00 f7 d8 64 89 01 48
RSP: 002b:00007ffe18f7f1e8 EFLAGS: 00000206 ORIG_RAX: 00000000000000b0
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f24e0043b07
RDX: 000000000000000a RSI: 0000000000000800 RDI: 0000555c3ecf87c8
RBP: 00007ffe18f7f1f0 R08: 0000000000000000 R09: 0000000000000000
R10: 00007f24e00b4ac0 R11: 0000000000000206 R12: 00007ffe18f7f238
R13: 00007ffe18f7f410 R14: 00007ffe18f80e73 R15: 0000555c3ecf8760

This patch, handling in the same way of pass two, unlocks the locks and
restart pass one after aoedev_downdev is done.

Fixes: 3582dd291788 ("aoe: convert aoeblk to blk-mq")
Signed-off-by: He Zhe 
Signed-off-by: Jens Axboe

nbd: replace kill_bdev() with __invalidate_device() again

2019-07-31T14:51:56+00:00

Commit abbbdf12497d ("replace kill_bdev() with __invalidate_device()")
once did this, but 29eaadc03649 ("nbd: stop using the bdev everywhere")
resurrected kill_bdev() and it has been there since then. So buffer_head
mappings still get killed on a server disconnection, and we can still
hit the BUG_ON on a filesystem on the top of the nbd device.

  EXT4-fs (nbd0): mounted filesystem with ordered data mode. Opts: (null)
  block nbd0: Receive control failed (result -32)
  block nbd0: shutting down sockets
  print_req_error: I/O error, dev nbd0, sector 66264 flags 3000
  EXT4-fs warning (device nbd0): htree_dirblock_to_tree:979: inode #2: lblock 0: comm ls: error -5 reading directory block
  print_req_error: I/O error, dev nbd0, sector 2264 flags 3000
  EXT4-fs error (device nbd0): __ext4_get_inode_loc:4690: inode #2: block 283: comm ls: unable to read itable block
  EXT4-fs error (device nbd0) in ext4_reserve_inode_write:5894: IO failure
  ------------[ cut here ]------------
  kernel BUG at fs/buffer.c:3057!
  invalid opcode: 0000 [#1] SMP PTI
  CPU: 7 PID: 40045 Comm: jbd2/nbd0-8 Not tainted 5.1.0-rc3+ #4
  Hardware name: Amazon EC2 m5.12xlarge/, BIOS 1.0 10/16/2017
  RIP: 0010:submit_bh_wbc+0x18b/0x190
  ...
  Call Trace:
   jbd2_write_superblock+0xf1/0x230 [jbd2]
   ? account_entity_enqueue+0xc5/0xf0
   jbd2_journal_update_sb_log_tail+0x94/0xe0 [jbd2]
   jbd2_journal_commit_transaction+0x12f/0x1d20 [jbd2]
   ? __switch_to_asm+0x40/0x70
   ...
   ? lock_timer_base+0x67/0x80
   kjournald2+0x121/0x360 [jbd2]
   ? remove_wait_queue+0x60/0x60
   kthread+0xf8/0x130
   ? commit_timeout+0x10/0x10 [jbd2]
   ? kthread_bind+0x10/0x10
   ret_from_fork+0x35/0x40

With __invalidate_device(), I no longer hit the BUG_ON with sync or
unmount on the disconnected device.

Fixes: 29eaadc03649 ("nbd: stop using the bdev everywhere")
Cc: linux-block@vger.kernel.org
Cc: Ratna Manoj Bolla 
Cc: nbd@other.debian.org
Cc: stable@vger.kernel.org
Cc: David Woodhouse 
Reviewed-by: Josef Bacik 
Signed-off-by: Munehisa Kamata 
Signed-off-by: Jens Axboe

loop: Fix mount(2) failure due to race with LOOP_SET_FD

2019-07-30T19:16:57+00:00

Commit 33ec3e53e7b1 ("loop: Don't change loop device under exclusive
opener") made LOOP_SET_FD ioctl acquire exclusive block device reference
while it updates loop device binding. However this can make perfectly
valid mount(2) fail with EBUSY due to racing LOOP_SET_FD holding
temporarily the exclusive bdev reference in cases like this:

for i in {a..z}{a..z}; do
        dd if=/dev/zero of=$i.image bs=1k count=0 seek=1024
        mkfs.ext2 $i.image
        mkdir mnt$i
done

echo "Run"
for i in {a..z}{a..z}; do
        mount -o loop -t ext2 $i.image mnt$i &
done

Fix the problem by not getting full exclusive bdev reference in
LOOP_SET_FD but instead just mark the bdev as being claimed while we
update the binding information. This just blocks new exclusive openers
instead of failing them with EBUSY thus fixing the problem.

Fixes: 33ec3e53e7b1 ("loop: Don't change loop device under exclusive opener")
Cc: stable@vger.kernel.org
Tested-by: Kai-Heng Feng 
Signed-off-by: Jan Kara 
Signed-off-by: Jens Axboe

ataflop: Mark expected switch fall-through

2019-07-29T21:24:58+00:00

Mark switch cases where we are expecting to fall through.

This patch fixes the following warning (Building: m68k):

drivers/block/ataflop.c: In function ‘fd_locked_ioctl’:
drivers/block/ataflop.c:1728:3: warning: this statement may fall through [-Wimplicit-fallthrough=]
   set_capacity(floppy->disk, MAX_DISK_SIZE * 2);
   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/block/ataflop.c:1729:2: note: here
  case FDFMTEND:
  ^~~~

Signed-off-by: Gustavo A. R. Silva 
Signed-off-by: Jens Axboe

Merge tag 'for-linus-20190726' of git://git.kernel.dk/linux-block

2019-07-26T17:32:12+00:00

Pull block fixes from Jens Axboe:

 - Several io_uring fixes/improvements:
     - Blocking fix for O_DIRECT (me)
     - Latter page slowness for registered buffers (me)
     - Fix poll hang under certain conditions (me)
     - Defer sequence check fix for wrapped rings (Zhengyuan)
     - Mismatch in async inc/dec accounting (Zhengyuan)
     - Memory ordering issue that could cause stall (Zhengyuan)
      - Track sequential defer in bytes, not pages (Zhengyuan)

 - NVMe pull request from Christoph

 - Set of hang fixes for wbt (Josef)

 - Redundant error message kill for libahci (Ding)

 - Remove unused blk_mq_sched_started_request() and related ops (Marcos)

 - drbd dynamic alloc shash descriptor to reduce stack use (Arnd)

 - blkcg ->pd_stat() non-debug print (Tejun)

 - bcache memory leak fix (Wei)

 - Comment fix (Akinobu)

 - BFQ perf regression fix (Paolo)

* tag 'for-linus-20190726' of git://git.kernel.dk/linux-block: (24 commits)
  io_uring: ensure ->list is initialized for poll commands
  Revert "nvme-pci: don't create a read hctx mapping without read queues"
  nvme: fix multipath crash when ANA is deactivated
  nvme: fix memory leak caused by incorrect subsystem free
  nvme: ignore subnqn for ADATA SX6000LNP
  drbd: dynamically allocate shash descriptor
  block: blk-mq: Remove blk_mq_sched_started_request and started_request
  bcache: fix possible memory leak in bch_cached_dev_run()
  io_uring: track io length in async_list based on bytes
  io_uring: don't use iov_iter_advance() for fixed buffers
  block: properly handle IOCB_NOWAIT for async O_DIRECT IO
  blk-mq: allow REQ_NOWAIT to return an error inline
  io_uring: add a memory barrier before atomic_read
  rq-qos: use a mb for got_token
  rq-qos: set ourself TASK_UNINTERRUPTIBLE after we schedule
  rq-qos: don't reset has_sleepers on spurious wakeups
  rq-qos: fix missed wake-ups in rq_qos_throttle
  wait: add wq_has_single_sleeper helper
  block, bfq: check also in-flight I/O in dispatch plugging
  block: fix sysfs module parameters directory path in comment
  ...

drbd: dynamically allocate shash descriptor

2019-07-23T13:35:18+00:00

Building with clang and KASAN, we get a warning about an overly large
stack frame on 32-bit architectures:

drivers/block/drbd/drbd_receiver.c:921:31: error: stack frame size of 1280 bytes in function 'conn_connect'
      [-Werror,-Wframe-larger-than=]

We already allocate other data dynamically in this function, so
just do the same for the shash descriptor, which makes up most of
this memory.

Link: https://lore.kernel.org/lkml/20190617132440.2721536-1-arnd@arndb.de/
Reviewed-by: Kees Cook 
Reviewed-by: Roland Kammerer 
Signed-off-by: Arnd Bergmann 
Signed-off-by: Jens Axboe

Merge tag 'ceph-for-5.3-rc1' of git://github.com/ceph/ceph-client

2019-07-18T18:05:25+00:00

Pull ceph updates from Ilya Dryomov:
 "Lots of exciting things this time!

   - support for rbd object-map and fast-diff features (myself). This
     will speed up reads, discards and things like snap diffs on sparse
     images.

   - ceph.snap.btime vxattr to expose snapshot creation time (David
     Disseldorp). This will be used to integrate with "Restore Previous
     Versions" feature added in Windows 7 for folks who reexport ceph
     through SMB.

   - security xattrs for ceph (Zheng Yan). Only selinux is supported for
     now due to the limitations of ->dentry_init_security().

   - support for MSG_ADDR2, FS_BTIME and FS_CHANGE_ATTR features (Jeff
     Layton). This is actually a single feature bit which was missing
     because of the filesystem pieces. With this in, the kernel client
     will finally be reported as "luminous" by "ceph features" -- it is
     still being reported as "jewel" even though all required Luminous
     features were implemented in 4.13.

   - stop NULL-terminating ceph vxattrs (Jeff Layton). The convention
     with xattrs is to not terminate and this was causing
     inconsistencies with ceph-fuse.

   - change filesystem time granularity from 1 us to 1 ns, again fixing
     an inconsistency with ceph-fuse (Luis Henriques).

  On top of this there are some additional dentry name handling and cap
  flushing fixes from Zheng. Finally, Jeff is formally taking over for
  Zheng as the filesystem maintainer"

* tag 'ceph-for-5.3-rc1' of git://github.com/ceph/ceph-client: (71 commits)
  ceph: fix end offset in truncate_inode_pages_range call
  ceph: use generic_delete_inode() for ->drop_inode
  ceph: use ceph_evict_inode to cleanup inode's resource
  ceph: initialize superblock s_time_gran to 1
  MAINTAINERS: take over for Zheng as CephFS kernel client maintainer
  rbd: setallochint only if object doesn't exist
  rbd: support for object-map and fast-diff
  rbd: call rbd_dev_mapping_set() from rbd_dev_image_probe()
  libceph: export osd_req_op_data() macro
  libceph: change ceph_osdc_call() to take page vector for response
  libceph: bump CEPH_MSG_MAX_DATA_LEN (again)
  rbd: new exclusive lock wait/wake code
  rbd: quiescing lock should wait for image requests
  rbd: lock should be quiesced on reacquire
  rbd: introduce copyup state machine
  rbd: rename rbd_obj_setup_*() to rbd_obj_init_*()
  rbd: move OSD request allocation into object request state machines
  rbd: factor out __rbd_osd_setup_discard_ops()
  rbd: factor out rbd_osd_setup_copyup()
  rbd: introduce obj_req->osd_reqs list
  ...

Merge branch 'floppy'

2019-07-18T15:43:20+00:00

Merge floppy ioctl verification fixes from Denis Efremov.

This also marks the floppy driver as orphaned - it turns out that Jiri
no longer has working hardware.

Actual working physical floppy hardware is getting hard to find, and
while Willy was able to test this, I think the driver can be considered
pretty much dead from an actual hardware standpoint.  The hardware that
is still sold seems to be mainly USB-based, which doesn't use this
legacy driver at all.

The old floppy disk controller is still emulated in various VM
environments, so the driver isn't going away, but let's see if anybody
is interested to step up to maintain it.

The lack of hardware also likely means that the ioctl range verification
fixes are probably mostly relevant to anybody using floppies in a
virtual environment.  Which is probably also going away in favor of USB
storage emulation, but who knows.

Will Decon reviewed the patches but I'm not rebasing them just for that,
so I'll add a

  Reviewed-by: Will Deacon 

here instead.

* floppy:
  MAINTAINERS: mark floppy.c orphaned
  floppy: fix out-of-bounds read in copy_buffer
  floppy: fix invalid pointer dereference in drive_name
  floppy: fix out-of-bounds read in next_valid_format
  floppy: fix div-by-zero in setup_format_params

floppy: fix out-of-bounds read in copy_buffer

2019-07-17T21:45:50+00:00

This fixes a global out-of-bounds read access in the copy_buffer
function of the floppy driver.

The FDDEFPRM ioctl allows one to set the geometry of a disk.  The sect
and head fields (unsigned int) of the floppy_drive structure are used to
compute the max_sector (int) in the make_raw_rw_request function.  It is
possible to overflow the max_sector.  Next, max_sector is passed to the
copy_buffer function and used in one of the memcpy calls.

An unprivileged user could trigger the bug if the device is accessible,
but requires a floppy disk to be inserted.

The patch adds the check for the .sect * .head multiplication for not
overflowing in the set_geometry function.

The bug was found by syzkaller.

Signed-off-by: Denis Efremov 
Tested-by: Willy Tarreau 
Signed-off-by: Linus Torvalds