Commit Graph

49342 Commits

Author SHA1 Message Date
Linus Torvalds 9bd42183b9 Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler updates from Ingo Molnar:
 "The main changes in this cycle were:

   - Add the SYSTEM_SCHEDULING bootup state to move various scheduler
     debug checks earlier into the bootup. This turns silent and
     sporadically deadly bugs into nice, deterministic splats. Fix some
     of the splats that triggered. (Thomas Gleixner)

   - A round of restructuring and refactoring of the load-balancing and
     topology code (Peter Zijlstra)

   - Another round of consolidating ~20 of incremental scheduler code
     history: this time in terms of wait-queue nomenclature. (I didn't
     get much feedback on these renaming patches, and we can still
     easily change any names I might have misplaced, so if anyone hates
     a new name, please holler and I'll fix it.) (Ingo Molnar)

   - sched/numa improvements, fixes and updates (Rik van Riel)

   - Another round of x86/tsc scheduler clock code improvements, in hope
     of making it more robust (Peter Zijlstra)

   - Improve NOHZ behavior (Frederic Weisbecker)

   - Deadline scheduler improvements and fixes (Luca Abeni, Daniel
     Bristot de Oliveira)

   - Simplify and optimize the topology setup code (Lauro Ramos
     Venancio)

   - Debloat and decouple scheduler code some more (Nicolas Pitre)

   - Simplify code by making better use of llist primitives (Byungchul
     Park)

   - ... plus other fixes and improvements"

* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (103 commits)
  sched/cputime: Refactor the cputime_adjust() code
  sched/debug: Expose the number of RT/DL tasks that can migrate
  sched/numa: Hide numa_wake_affine() from UP build
  sched/fair: Remove effective_load()
  sched/numa: Implement NUMA node level wake_affine()
  sched/fair: Simplify wake_affine() for the single socket case
  sched/numa: Override part of migrate_degrades_locality() when idle balancing
  sched/rt: Move RT related code from sched/core.c to sched/rt.c
  sched/deadline: Move DL related code from sched/core.c to sched/deadline.c
  sched/cpuset: Only offer CONFIG_CPUSETS if SMP is enabled
  sched/fair: Spare idle load balancing on nohz_full CPUs
  nohz: Move idle balancer registration to the idle path
  sched/loadavg: Generalize "_idle" naming to "_nohz"
  sched/core: Drop the unused try_get_task_struct() helper function
  sched/fair: WARN() and refuse to set buddy when !se->on_rq
  sched/debug: Fix SCHED_WARN_ON() to return a value on !CONFIG_SCHED_DEBUG as well
  sched/wait: Disambiguate wq_entry->task_list and wq_head->task_list naming
  sched/wait: Move bit_wait_table[] and related functionality from sched/core.c to sched/wait_bit.c
  sched/wait: Split out the wait_bit*() APIs from <linux/wait.h> into <linux/wait_bit.h>
  sched/wait: Re-adjust macro line continuation backslashes in <linux/wait.h>
  ...
2017-07-03 13:08:04 -07:00
Linus Torvalds c6b1e36c8f Merge branch 'for-4.13/block' of git://git.kernel.dk/linux-block
Pull core block/IO updates from Jens Axboe:
 "This is the main pull request for the block layer for 4.13. Not a huge
  round in terms of features, but there's a lot of churn related to some
  core cleanups.

  Note this depends on the UUID tree pull request, that Christoph
  already sent out.

  This pull request contains:

   - A series from Christoph, unifying the error/stats codes in the
     block layer. We now use blk_status_t everywhere, instead of using
     different schemes for different places.

   - Also from Christoph, some cleanups around request allocation and IO
     scheduler interactions in blk-mq.

   - And yet another series from Christoph, cleaning up how we handle
     and do bounce buffering in the block layer.

   - A blk-mq debugfs series from Bart, further improving on the support
     we have for exporting internal information to aid debugging IO
     hangs or stalls.

   - Also from Bart, a series that cleans up the request initialization
     differences across types of devices.

   - A series from Goldwyn Rodrigues, allowing the block layer to return
     failure if we will block and the user asked for non-blocking.

   - Patch from Hannes for supporting setting loop devices block size to
     that of the underlying device.

   - Two series of patches from Javier, fixing various issues with
     lightnvm, particular around pblk.

   - A series from me, adding support for write hints. This comes with
     NVMe support as well, so applications can help guide data placement
     on flash to improve performance, latencies, and write
     amplification.

   - A series from Ming, improving and hardening blk-mq support for
     stopping/starting and quiescing hardware queues.

   - Two pull requests for NVMe updates. Nothing major on the feature
     side, but lots of cleanups and bug fixes. From the usual crew.

   - A series from Neil Brown, greatly improving the bio rescue set
     support. Most notably, this kills the bio rescue work queues, if we
     don't really need them.

   - Lots of other little bug fixes that are all over the place"

* 'for-4.13/block' of git://git.kernel.dk/linux-block: (217 commits)
  lightnvm: pblk: set line bitmap check under debug
  lightnvm: pblk: verify that cache read is still valid
  lightnvm: pblk: add initialization check
  lightnvm: pblk: remove target using async. I/Os
  lightnvm: pblk: use vmalloc for GC data buffer
  lightnvm: pblk: use right metadata buffer for recovery
  lightnvm: pblk: schedule if data is not ready
  lightnvm: pblk: remove unused return variable
  lightnvm: pblk: fix double-free on pblk init
  lightnvm: pblk: fix bad le64 assignations
  nvme: Makefile: remove dead build rule
  blk-mq: map all HWQ also in hyperthreaded system
  nvmet-rdma: register ib_client to not deadlock in device removal
  nvme_fc: fix error recovery on link down.
  nvmet_fc: fix crashes on bad opcodes
  nvme_fc: Fix crash when nvme controller connection fails.
  nvme_fc: replace ioabort msleep loop with completion
  nvme_fc: fix double calls to nvme_cleanup_cmd()
  nvme-fabrics: verify that a controller returns the correct NQN
  nvme: simplify nvme_dev_attrs_are_visible
  ...
2017-07-03 10:34:51 -07:00
Linus Torvalds 81e3e04489 UUID/GUID updates:
- introduce the new uuid_t/guid_t types that are going to replace
    the somewhat confusing uuid_be/uuid_le types and make the terminology
    fit the various specs, as well as the userspace libuuid library.
    (me, based on a previous version from Amir)
  - consolidated generic uuid/guid helper functions lifted from XFS
    and libnvdimm (Amir and me)
  - conversions to the new types and helpers (Amir, Andy and me)
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Merge tag 'uuid-for-4.13' of git://git.infradead.org/users/hch/uuid

Pull uuid subsystem from Christoph Hellwig:
 "This is the new uuid subsystem, in which Amir, Andy and I have started
  consolidating our uuid/guid helpers and improving the types used for
  them. Note that various other subsystems have pulled in this tree, so
  I'd like it to go in early.

  UUID/GUID summary:

   - introduce the new uuid_t/guid_t types that are going to replace the
     somewhat confusing uuid_be/uuid_le types and make the terminology
     fit the various specs, as well as the userspace libuuid library.
     (me, based on a previous version from Amir)

   - consolidated generic uuid/guid helper functions lifted from XFS and
     libnvdimm (Amir and me)

   - conversions to the new types and helpers (Amir, Andy and me)"

* tag 'uuid-for-4.13' of git://git.infradead.org/users/hch/uuid: (34 commits)
  ACPI: hns_dsaf_acpi_dsm_guid can be static
  mmc: sdhci-pci: make guid intel_dsm_guid static
  uuid: Take const on input of uuid_is_null() and guid_is_null()
  thermal: int340x_thermal: fix compile after the UUID API switch
  thermal: int340x_thermal: Switch to use new generic UUID API
  acpi: always include uuid.h
  ACPI: Switch to use generic guid_t in acpi_evaluate_dsm()
  ACPI / extlog: Switch to use new generic UUID API
  ACPI / bus: Switch to use new generic UUID API
  ACPI / APEI: Switch to use new generic UUID API
  acpi, nfit: Switch to use new generic UUID API
  MAINTAINERS: add uuid entry
  tmpfs: generate random sb->s_uuid
  scsi_debug: switch to uuid_t
  nvme: switch to uuid_t
  sysctl: switch to use uuid_t
  partitions/ldm: switch to use uuid_t
  overlayfs: use uuid_t instead of uuid_be
  fs: switch ->s_uuid to uuid_t
  ima/policy: switch to use uuid_t
  ...
2017-07-03 09:55:26 -07:00
Linus Torvalds 86c3e00afd Merge branch 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs
Pull overlayfs fixes from Miklos Szeredi:
 "Fix two bugs in copy-up code. One introduced in 4.11 and one in
  4.12-rc"

* 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs:
  ovl: don't set origin on broken lower hardlink
  ovl: copy-up: don't unlock between lookup and link
2017-06-30 10:22:59 -07:00
Linus Torvalds 374bf8831a Merge branch 'for-linus' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe:
 "Two fixes that should go into this release.

  One is an nvme regression fix from Keith, fixing a missing queue
  freeze if the controller is being reset. This causes the reset to
  hang.

  The other is a fix for a leak of the bio protection info, if smaller
  sized O_DIRECT is used. This fix should be more involved as we have
  other problematic paths in the kernel, but given as this isn't a
  regression in this series, we'll tackle those for 4.13"

* 'for-linus' of git://git.kernel.dk/linux-block:
  block: provide bio_uninit() free freeing integrity/task associations
  nvme/pci: Fix stuck nvme reset
2017-06-29 14:10:37 -07:00
Jens Axboe 9ae3b3f52c block: provide bio_uninit() free freeing integrity/task associations
Wen reports significant memory leaks with DIF and O_DIRECT:

"With nvme devive + T10 enabled, On a system it has 256GB and started
logging /proc/meminfo & /proc/slabinfo for every minute and in an hour
it increased by 15968128 kB or ~15+GB.. Approximately 256 MB / minute
leaking.

/proc/meminfo | grep SUnreclaim...

SUnreclaim:      6752128 kB
SUnreclaim:      6874880 kB
SUnreclaim:      7238080 kB
....
SUnreclaim:     22307264 kB
SUnreclaim:     22485888 kB
SUnreclaim:     22720256 kB

When testcases with T10 enabled call into __blkdev_direct_IO_simple,
code doesn't free memory allocated by bio_integrity_alloc. The patch
fixes the issue. HTX has been run with +60 hours without failure."

Since __blkdev_direct_IO_simple() allocates the bio on the stack, it
doesn't go through the regular bio free. This means that any ancillary
data allocated with the bio through the stack is not freed. Hence, we
can leak the integrity data associated with the bio, if the device is
using DIF/DIX.

Fix this by providing a bio_uninit() and export it, so that we can use
it to free this data. Note that this is a minimal fix for this issue.
Any current user of bio's that are allocated outside of
bio_alloc_bioset() suffers from this issue, most notably some drivers.
We will fix those in a more comprehensive patch for 4.13. This also
means that the commit marked as being fixed by this isn't the real
culprit, it's just the most obvious one out there.

Fixes: 542ff7bf18 ("block: new direct I/O implementation")
Reported-by: Wen Xiong <wenxiong@linux.vnet.ibm.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-28 15:30:13 -06:00
Linus Torvalds e547204f1f NFS client bugfixes for Linux 4.12
Bugfixes include:
 
 - Stable fix for exclusive create if the server supports the umask attribute
 - Trunking detection should handle ERESTARTSYS/EINTR
 - Stable fix for a race in the LAYOUTGET function
 - Stable fix to revert "nfs_rename() handle -ERESTARTSYS dentry left behind"
 - nfs4_callback_free_slot() cannot call nfs4_slot_tbl_drain_complete()
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Merge tag 'nfs-for-4.12-3' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

Pull NFS client bugfixes from Trond Myklebust:
 "Bugfixes include:

   - stable fix for exclusive create if the server supports the umask
     attribute

   - trunking detection should handle ERESTARTSYS/EINTR

   - stable fix for a race in the LAYOUTGET function

   - stable fix to revert "nfs_rename() handle -ERESTARTSYS dentry left
     behind"

   - nfs4_callback_free_slot() cannot call nfs4_slot_tbl_drain_complete()"

* tag 'nfs-for-4.12-3' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
  NFSv4.1: nfs4_callback_free_slot() cannot call nfs4_slot_tbl_drain_complete()
  Revert "NFS: nfs_rename() handle -ERESTARTSYS dentry left behind"
  NFSv4.1: Fix a race in nfs4_proc_layoutget
  NFS: Trunking detection should handle ERESTARTSYS/EINTR
  NFSv4.2: Don't send mode again in post-EXCLUSIVE4_1 SETATTR with umask
2017-06-28 13:27:15 -07:00
Jens Axboe 5657cb0797 fs/fcntl: use copy_to/from_user() for u64 types
Some architectures (at least PPC) doesn't like get/put_user with
64-bit types on a 32-bit system. Use the variably sized copy
to/from user variants instead.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Fixes: c75b1d9421 ("fs: add fcntl() interface for setting/getting write life time hints")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-28 08:09:45 -06:00
Miklos Szeredi fbaf94ee3c ovl: don't set origin on broken lower hardlink
When copying up a file that has multiple hard links we need to break any
association with the origin file.  This makes copy-up be essentially an
atomic replace.

The new file has nothing to do with the old one (except having the same
data and metadata initially), so don't set the overlay.origin attribute.

We can relax this in the future when we are able to index upper object by
origin.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Fixes: 3a1e819b4e ("ovl: store file handle of lower inode on copy up")
2017-06-28 13:41:22 +02:00
Miklos Szeredi e85f82ff9b ovl: copy-up: don't unlock between lookup and link
Nothing prevents mischief on upper layer while we are busy copying up the
data.

Move the lookup right before the looked up dentry is actually used.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Fixes: 01ad3eb8a0 ("ovl: concurrent copy up of regular files")
Cc: <stable@vger.kernel.org> # v4.11
2017-06-28 13:41:22 +02:00
Trond Myklebust 2e31b4cb89 NFSv4.1: nfs4_callback_free_slot() cannot call nfs4_slot_tbl_drain_complete()
The current code works only for the case where we have exactly one slot,
which is no longer true.
nfs4_free_slot() will automatically declare the callback channel to be
drained when all slots have been returned.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-06-27 22:26:23 -04:00
Benjamin Coddington d9f2950006 Revert "NFS: nfs_rename() handle -ERESTARTSYS dentry left behind"
This reverts commit 920b4530fb which could
call d_move() without holding the directory's i_mutex, and reverts commit
d4ea7e3c5c "NFS: Fix old dentry rehash after
move", which was a follow-up fix.

Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Fixes: 920b4530fb ("NFS: nfs_rename() handle -ERESTARTSYS dentry left behind")
Cc: stable@vger.kernel.org # v4.10+
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-06-27 21:58:14 -04:00
Trond Myklebust bd171930e6 NFSv4.1: Fix a race in nfs4_proc_layoutget
If the task calling layoutget is signalled, then it is possible for the
calls to nfs4_sequence_free_slot() and nfs4_layoutget_prepare() to race,
in which case we leak a slot.
The fix is to move the call to nfs4_sequence_free_slot() into the
nfs4_layoutget_release() so that it gets called at task teardown time.

Fixes: 2e80dbe7ac ("NFSv4.1: Close callback races for OPEN, LAYOUTGET...")
Cc: stable@vger.kernel.org # v4.8+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-06-27 21:44:58 -04:00
Trond Myklebust 898fc11bb2 NFS: Trunking detection should handle ERESTARTSYS/EINTR
Currently, it will return EIO in those cases.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-06-27 21:44:58 -04:00
Jens Axboe e6959b9350 btrfs: add support for passing in write hints for buffered writes
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Chris Mason <clm@fb.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-27 12:05:52 -06:00
Jens Axboe 31d7d58dcc xfs: add support for passing in write hints for buffered writes
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-27 12:05:48 -06:00
Jens Axboe 0127251c45 ext4: add support for passing in write hints for buffered writes
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-27 12:05:44 -06:00
Jens Axboe 8e8f929881 fs: add support for buffered writeback to pass down write hints
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-27 12:05:39 -06:00
Jens Axboe 45d06cf701 fs: add O_DIRECT and aio support for sending down write life time hints
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-27 12:05:36 -06:00
Jens Axboe c75b1d9421 fs: add fcntl() interface for setting/getting write life time hints
Define a set of write life time hints:

RWH_WRITE_LIFE_NOT_SET	No hint information set
RWH_WRITE_LIFE_NONE	No hints about write life time
RWH_WRITE_LIFE_SHORT	Data written has a short life time
RWH_WRITE_LIFE_MEDIUM	Data written has a medium life time
RWH_WRITE_LIFE_LONG	Data written has a long life time
RWH_WRITE_LIFE_EXTREME	Data written has an extremely long life time

The intent is for these values to be relative to each other, no
absolute meaning should be attached to these flag names.

Add an fcntl interface for querying these flags, and also for
setting them as well:

F_GET_RW_HINT		Returns the read/write hint set on the
			underlying inode.

F_SET_RW_HINT		Set one of the above write hints on the
			underlying inode.

F_GET_FILE_RW_HINT	Returns the read/write hint set on the
			file descriptor.

F_SET_FILE_RW_HINT	Set one of the above write hints on the
			file descriptor.

The user passes in a 64-bit pointer to get/set these values, and
the interface returns 0/-1 on success/error.

Sample program testing/implementing basic setting/getting of write
hints is below.

Add support for storing the write life time hint in the inode flags
and in struct file as well, and pass them to the kiocb flags. If
both a file and its corresponding inode has a write hint, then we
use the one in the file, if available. The file hint can be used
for sync/direct IO, for buffered writeback only the inode hint
is available.

This is in preparation for utilizing these hints in the block layer,
to guide on-media data placement.

/*
 * writehint.c: get or set an inode write hint
 */
 #include <stdio.h>
 #include <fcntl.h>
 #include <stdlib.h>
 #include <unistd.h>
 #include <stdbool.h>
 #include <inttypes.h>

 #ifndef F_GET_RW_HINT
 #define F_LINUX_SPECIFIC_BASE	1024
 #define F_GET_RW_HINT		(F_LINUX_SPECIFIC_BASE + 11)
 #define F_SET_RW_HINT		(F_LINUX_SPECIFIC_BASE + 12)
 #endif

static char *str[] = { "RWF_WRITE_LIFE_NOT_SET", "RWH_WRITE_LIFE_NONE",
			"RWH_WRITE_LIFE_SHORT", "RWH_WRITE_LIFE_MEDIUM",
			"RWH_WRITE_LIFE_LONG", "RWH_WRITE_LIFE_EXTREME" };

int main(int argc, char *argv[])
{
	uint64_t hint;
	int fd, ret;

	if (argc < 2) {
		fprintf(stderr, "%s: file <hint>\n", argv[0]);
		return 1;
	}

	fd = open(argv[1], O_RDONLY);
	if (fd < 0) {
		perror("open");
		return 2;
	}

	if (argc > 2) {
		hint = atoi(argv[2]);
		ret = fcntl(fd, F_SET_RW_HINT, &hint);
		if (ret < 0) {
			perror("fcntl: F_SET_RW_HINT");
			return 4;
		}
	}

	ret = fcntl(fd, F_GET_RW_HINT, &hint);
	if (ret < 0) {
		perror("fcntl: F_GET_RW_HINT");
		return 3;
	}

	printf("%s: hint %s\n", argv[1], str[hint]);
	close(fd);
	return 0;
}

Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-27 12:05:22 -06:00
Ingo Molnar 1bc3cd4dfa Merge branch 'linus' into sched/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-24 08:57:20 +02:00
Linus Torvalds 337c6ba2d8 Merge branch 'akpm' (patches from Andrew)
Merge misc fixes from Andrew Morton:
 "8 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  fs/exec.c: account for argv/envp pointers
  ocfs2: fix deadlock caused by recursive locking in xattr
  slub: make sysfs file removal asynchronous
  lib/cmdline.c: fix get_options() overflow while parsing ranges
  fs/dax.c: fix inefficiency in dax_writeback_mapping_range()
  autofs: sanity check status reported with AUTOFS_DEV_IOCTL_FAIL
  mm/vmalloc.c: huge-vmap: fail gracefully on unexpected huge vmap mappings
  mm, thp: remove cond_resched from __collapse_huge_page_copy
2017-06-23 16:30:52 -07:00
Kees Cook 98da7d0885 fs/exec.c: account for argv/envp pointers
When limiting the argv/envp strings during exec to 1/4 of the stack limit,
the storage of the pointers to the strings was not included.  This means
that an exec with huge numbers of tiny strings could eat 1/4 of the stack
limit in strings and then additional space would be later used by the
pointers to the strings.

For example, on 32-bit with a 8MB stack rlimit, an exec with 1677721
single-byte strings would consume less than 2MB of stack, the max (8MB /
4) amount allowed, but the pointers to the strings would consume the
remaining additional stack space (1677721 * 4 == 6710884).

The result (1677721 + 6710884 == 8388605) would exhaust stack space
entirely.  Controlling this stack exhaustion could result in
pathological behavior in setuid binaries (CVE-2017-1000365).

[akpm@linux-foundation.org: additional commenting from Kees]
Fixes: b6a2fea393 ("mm: variable length argument support")
Link: http://lkml.kernel.org/r/20170622001720.GA32173@beast
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Rik van Riel <riel@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Qualys Security Advisory <qsa@qualys.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-06-23 16:15:56 -07:00
Eric Ren 8818efaaac ocfs2: fix deadlock caused by recursive locking in xattr
Another deadlock path caused by recursive locking is reported.  This
kind of issue was introduced since commit 743b5f1434 ("ocfs2: take
inode lock in ocfs2_iop_set/get_acl()").  Two deadlock paths have been
fixed by commit b891fa5024 ("ocfs2: fix deadlock issue when taking
inode lock at vfs entry points").  Yes, we intend to fix this kind of
case in incremental way, because it's hard to find out all possible
paths at once.

This one can be reproduced like this.  On node1, cp a large file from
home directory to ocfs2 mountpoint.  While on node2, run
setfacl/getfacl.  Both nodes will hang up there.  The backtraces:

On node1:
  __ocfs2_cluster_lock.isra.39+0x357/0x740 [ocfs2]
  ocfs2_inode_lock_full_nested+0x17d/0x840 [ocfs2]
  ocfs2_write_begin+0x43/0x1a0 [ocfs2]
  generic_perform_write+0xa9/0x180
  __generic_file_write_iter+0x1aa/0x1d0
  ocfs2_file_write_iter+0x4f4/0xb40 [ocfs2]
  __vfs_write+0xc3/0x130
  vfs_write+0xb1/0x1a0
  SyS_write+0x46/0xa0

On node2:
  __ocfs2_cluster_lock.isra.39+0x357/0x740 [ocfs2]
  ocfs2_inode_lock_full_nested+0x17d/0x840 [ocfs2]
  ocfs2_xattr_set+0x12e/0xe80 [ocfs2]
  ocfs2_set_acl+0x22d/0x260 [ocfs2]
  ocfs2_iop_set_acl+0x65/0xb0 [ocfs2]
  set_posix_acl+0x75/0xb0
  posix_acl_xattr_set+0x49/0xa0
  __vfs_setxattr+0x69/0x80
  __vfs_setxattr_noperm+0x72/0x1a0
  vfs_setxattr+0xa7/0xb0
  setxattr+0x12d/0x190
  path_setxattr+0x9f/0xb0
  SyS_setxattr+0x14/0x20

Fix this one by using ocfs2_inode_{lock|unlock}_tracker, which is
exported by commit 439a36b8ef ("ocfs2/dlmglue: prepare tracking logic
to avoid recursive cluster lock").

Link: http://lkml.kernel.org/r/20170622014746.5815-1-zren@suse.com
Fixes: 743b5f1434 ("ocfs2: take inode lock in ocfs2_iop_set/get_acl()")
Signed-off-by: Eric Ren <zren@suse.com>
Reported-by: Thomas Voegtle <tv@lio96.de>
Tested-by: Thomas Voegtle <tv@lio96.de>
Reviewed-by: Joseph Qi <jiangqi903@gmail.com>
Cc: Mark Fasheh <mfasheh@versity.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-06-23 16:15:55 -07:00
Jan Kara 1eb643d02b fs/dax.c: fix inefficiency in dax_writeback_mapping_range()
dax_writeback_mapping_range() fails to update iteration index when
searching radix tree for entries needing cache flushing.  Thus each
pagevec worth of entries is searched starting from the start which is
inefficient and prone to livelocks.  Update index properly.

Link: http://lkml.kernel.org/r/20170619124531.21491-1-jack@suse.cz
Fixes: 9973c98ecf ("dax: add support for fsync/sync")
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-06-23 16:15:55 -07:00
NeilBrown 9fa4eb8e49 autofs: sanity check status reported with AUTOFS_DEV_IOCTL_FAIL
If a positive status is passed with the AUTOFS_DEV_IOCTL_FAIL ioctl,
autofs4_d_automount() will return

   ERR_PTR(status)

with that status to follow_automount(), which will then dereference an
invalid pointer.

So treat a positive status the same as zero, and map to ENOENT.

See comment in systemd src/core/automount.c::automount_send_ready().

Link: http://lkml.kernel.org/r/871sqwczx5.fsf@notabene.neil.brown.name
Signed-off-by: NeilBrown <neilb@suse.com>
Cc: Ian Kent <raven@themaw.net>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-06-23 16:15:55 -07:00
Linus Torvalds 7b249bdc3d Changes since last update:
- don't allow swapon on files on the realtime device, because the swap
   code will swap pages out to blocks on the data device, thereby
   corrupting the filesystem
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Merge tag 'xfs-4.12-fixes-5' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

Pull xfs fixes from Darrick Wong:
 "I have one more bugfix for you for 4.12-rc7 to fix a disk corruption
  problem:

   - don't allow swapon on files on the realtime device, because the
     swap code will swap pages out to blocks on the data device, thereby
     corrupting the filesystem"

* tag 'xfs-4.12-fixes-5' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  xfs: don't allow bmap on rt files
2017-06-23 12:23:06 -07:00
Linus Torvalds a38371cba6 Merge branch 'for-next' of git://git.samba.org/sfrench/cifs-2.6
Pull cifs fixes from Steve French:
 "Various small fixes for stable"

* 'for-next' of git://git.samba.org/sfrench/cifs-2.6:
  CIFS: Fix some return values in case of error in 'crypt_message'
  cifs: remove redundant return in cifs_creation_time_get
  CIFS: Improve readdir verbosity
  CIFS: check if pages is null rather than bv for a failed allocation
  CIFS: Set ->should_dirty in cifs_user_readv()
2017-06-22 11:16:55 -07:00
Darrick J. Wong eb5e248d50 xfs: don't allow bmap on rt files
bmap returns a dumb LBA address but not the block device that goes with
that LBA.  Swapfiles don't care about this and will blindly assume that
the data volume is the correct blockdev, which is totally bogus for
files on the rt subvolume.  This results in the swap code doing IOs to
arbitrary locations on the data device(!) if the passed in mapping is a
realtime file, so just turn off bmap for rt files.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2017-06-21 20:27:35 -07:00
Linus Torvalds 021f601980 Merge branch 'ufs-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull more ufs fixes from Al Viro:
 "More UFS fixes, unfortunately including build regression fix for the
  64-bit s_dsize commit. Fixed in this pile:

   - trivial bug in signedness of 32bit timestamps on ufs1

   - ESTALE instead of ufs_error() when doing open-by-fhandle on
     something deleted

   - build regression on 32bit in ufs_new_fragments() - calculating that
     many percents of u64 pulls libgcc stuff on some of those. Mea
     culpa.

   - fix hysteresis loop broken by typo in 2.4.14.7 (right next to the
     location of previous bug).

   - fix the insane limits of said hysteresis loop on filesystems with
     very low percentage of reserved blocks. If it's 5% or less, just
     use the OPTSPACE policy.

   - calculate those limits once and mount time.

  This tree does pass xfstests clean (both ufs1 and ufs2) and it _does_
  survive cross-builds.

  Again, my apologies for missing that, especially since I have noticed
  a related percentage-of-64bit issue in earlier patches (when dealing
  with amount of reserved blocks). Self-LART applied..."

* 'ufs-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  ufs: fix the logics for tail relocation
  ufs_iget(): fail with -ESTALE on deleted inode
  fix signedness of timestamps on ufs1
2017-06-21 11:30:52 -07:00
Dan Carpenter 0e9350de2e btrfs: use new block error code
This function is supposed to return blk_status_t error codes now but
there was a stray -ENOMEM left behind.

Fixes: 4e4cbee93d ("block: switch bios to blk_status_t")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Acked-by: David Sterba <dsterba@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-21 07:47:34 -06:00
Christophe Jaillet 517a6e43c4 CIFS: Fix some return values in case of error in 'crypt_message'
'rc' is known to be 0 at this point. So if 'init_sg' or 'kzalloc' fails, we
should return -ENOMEM instead.

Also remove a useless 'rc' in a debug message as it is meaningless here.

Fixes: 026e93dc0a ("CIFS: Encrypt SMB3 requests before sending")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <smfrench@gmail.com>
CC: Stable <stable@vger.kernel.org>
2017-06-21 00:09:28 -05:00
Bart Van Assche ca18d6f769 block: Make most scsi_req_init() calls implicit
Instead of explicitly calling scsi_req_init() after blk_get_request(),
call that function from inside blk_get_request(). Add an
.initialize_rq_fn() callback function to the block drivers that need
it. Merge the IDE .init_rq_fn() function into .initialize_rq_fn()
because it is too small to keep it as a separate function. Keep the
scsi_req_init() call in ide_prep_sense() because it follows a
blk_rq_init() call.

References: commit 82ed4db499 ("block: split scsi_request out of struct request")
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Omar Sandoval <osandov@fb.com>
Cc: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-20 19:27:14 -06:00
Colin Ian King e125f5284f cifs: remove redundant return in cifs_creation_time_get
There is a redundant return in function cifs_creation_time_get
that appears to be old vestigial code than can be removed. So
remove it.

Detected by CoverityScan, CID#1361924 ("Structurally dead code")

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2017-06-20 19:14:40 -05:00
Pavel Shilovsky dcd87838c0 CIFS: Improve readdir verbosity
Downgrade the loglevel for SMB2 to prevent filling the log
with messages if e.g. readdir was interrupted. Also make SMB2
and SMB1 codepaths do the same logging during readdir.

Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <smfrench@gmail.com>
CC: Stable <stable@vger.kernel.org>
2017-06-20 19:13:47 -05:00
Colin Ian King ecf3411a12 CIFS: check if pages is null rather than bv for a failed allocation
pages is being allocated however a null check on bv is being used
to see if the allocation failed. Fix this by checking if pages is
null.

Detected by CoverityScan, CID#1432974 ("Logically dead code")

Fixes: ccf7f4088a ("CIFS: Add asynchronous context to support kernel AIO")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2017-06-20 19:11:35 -05:00
Dan Carpenter 8a7b0d8e8d CIFS: Set ->should_dirty in cifs_user_readv()
The current code causes a static checker warning because ITER_IOVEC is
zero so the condition is never true.

Fixes: 6685c5e2d1 ("CIFS: Add asynchronous read support through kernel AIO")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2017-06-20 17:57:27 -05:00
Goldwyn Rodrigues edf064e7c6 btrfs: nowait aio support
Return EAGAIN if any of the following checks fail
 + i_rwsem is not lockable
 + NODATACOW or PREALLOC is not set
 + Cannot nocow at the desired location
 + Writing beyond end of file which is not allocated

Acked-by: David Sterba <dsterba@suse.com>
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-20 07:12:03 -06:00
Goldwyn Rodrigues 29a5d29ec1 xfs: nowait aio support
If IOCB_NOWAIT is set, bail if the i_rwsem is not lockable
immediately.

IF IOMAP_NOWAIT is set, return EAGAIN in xfs_file_iomap_begin
if it needs allocation either due to file extension, writing to a hole,
or COW or waiting for other DIOs to finish.

Return -EAGAIN if we don't have extent list in memory.

Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-20 07:12:03 -06:00
Goldwyn Rodrigues 728fbc0e10 ext4: nowait aio support
Return EAGAIN if any of the following checks fail for direct I/O:
  + i_rwsem is lockable
  + Writing beyond end of file (will trigger allocation)
  + Blocks are not allocated at the write location

Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-20 07:12:03 -06:00
Goldwyn Rodrigues 03a07c92a9 block: return on congested block device
A new bio operation flag REQ_NOWAIT is introduced to identify bio's
orignating from iocb with IOCB_NOWAIT. This flag indicates
to return immediately if a request cannot be made instead
of retrying.

Stacked devices such as md (the ones with make_request_fn hooks)
currently are not supported because it may block for housekeeping.
For example, an md can have a part of the device suspended.
For this reason, only request based devices are supported.
In the future, this feature will be expanded to stacked devices
by teaching them how to handle the REQ_NOWAIT flags.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-20 07:12:03 -06:00
Goldwyn Rodrigues a38d124370 fs: Introduce IOMAP_NOWAIT
IOCB_NOWAIT translates to IOMAP_NOWAIT for iomaps.
This is used by XFS in the XFS patch.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-20 07:12:03 -06:00
Goldwyn Rodrigues b745fafaf7 fs: Introduce RWF_NOWAIT and FMODE_AIO_NOWAIT
RWF_NOWAIT informs kernel to bail out if an AIO request will block
for reasons such as file allocations, or a writeback triggered,
or would block while allocating requests while performing
direct I/O.

RWF_NOWAIT is translated to IOCB_NOWAIT for iocb->ki_flags.

FMODE_AIO_NOWAIT is a flag which identifies the file opened is capable
of returning -EAGAIN if the AIO call will block. This must be set by
supporting filesystems in the ->open() call.

Filesystems xfs, btrfs and ext4 would be supported in the following patches.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-20 07:12:03 -06:00
Goldwyn Rodrigues 9830f4be15 fs: Use RWF_* flags for AIO operations
aio_rw_flags is introduced in struct iocb (using aio_reserved1) which will
carry the RWF_* flags. We cannot use aio_flags because they are not
checked for validity which may break existing applications.

Note, the only place RWF_HIPRI comes in effect is dio_await_one().
All the rest of the locations, aio code return -EIOCBQUEUED before the
checks for RWF_HIPRI.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-20 07:12:03 -06:00
Goldwyn Rodrigues fdd2f5b7de fs: Separate out kiocb flags setup based on RWF_* flags
Also added RWF_SUPPORTED to encompass all flags.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-20 07:12:03 -06:00
Ingo Molnar 2055da9738 sched/wait: Disambiguate wq_entry->task_list and wq_head->task_list naming
So I've noticed a number of instances where it was not obvious from the
code whether ->task_list was for a wait-queue head or a wait-queue entry.

Furthermore, there's a number of wait-queue users where the lists are
not for 'tasks' but other entities (poll tables, etc.), in which case
the 'task_list' name is actively confusing.

To clear this all up, name the wait-queue head and entry list structure
fields unambiguously:

	struct wait_queue_head::task_list	=> ::head
	struct wait_queue_entry::task_list	=> ::entry

For example, this code:

	rqw->wait.task_list.next != &wait->task_list

... is was pretty unclear (to me) what it's doing, while now it's written this way:

	rqw->wait.head.next != &wait->entry

... which makes it pretty clear that we are iterating a list until we see the head.

Other examples are:

	list_for_each_entry_safe(pos, next, &x->task_list, task_list) {
	list_for_each_entry(wq, &fence->wait.task_list, task_list) {

... where it's unclear (to me) what we are iterating, and during review it's
hard to tell whether it's trying to walk a wait-queue entry (which would be
a bug), while now it's written as:

	list_for_each_entry_safe(pos, next, &x->head, entry) {
	list_for_each_entry(wq, &fence->wait.head, entry) {

Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-20 12:19:14 +02:00
Ingo Molnar 5dd43ce2f6 sched/wait: Split out the wait_bit*() APIs from <linux/wait.h> into <linux/wait_bit.h>
The wait_bit*() types and APIs are mixed into wait.h, but they
are a pretty orthogonal extension of wait-queues.

Furthermore, only about 50 kernel files use these APIs, while
over 1000 use the regular wait-queue functionality.

So clean up the main wait.h by moving the wait-bit functionality
out of it, into a separate .h and .c file:

  include/linux/wait_bit.h  for types and APIs
  kernel/sched/wait_bit.c   for the implementation

Update all header dependencies.

This reduces the size of wait.h rather significantly, by about 30%.

Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-20 12:19:09 +02:00
Ingo Molnar 2141713616 sched/wait: Standardize 'struct wait_bit_queue' wait-queue entry field name
Rename 'struct wait_bit_queue::wait' to ::wq_entry, to more clearly
name it as a wait-queue entry.

Propagate it to a couple of usage sites where the wait-bit-queue internals
are exposed.

Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-20 12:18:28 +02:00
Ingo Molnar ac6424b981 sched/wait: Rename wait_queue_t => wait_queue_entry_t
Rename:

	wait_queue_t		=>	wait_queue_entry_t

'wait_queue_t' was always a slight misnomer: its name implies that it's a "queue",
but in reality it's a queue *entry*. The 'real' queue is the wait queue head,
which had to carry the name.

Start sorting this out by renaming it to 'wait_queue_entry_t'.

This also allows the real structure name 'struct __wait_queue' to
lose its double underscore and become 'struct wait_queue_entry',
which is the more canonical nomenclature for such data types.

Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-20 12:18:27 +02:00
Hugh Dickins 1be7107fbe mm: larger stack guard gap, between vmas
Stack guard page is a useful feature to reduce a risk of stack smashing
into a different mapping. We have been using a single page gap which
is sufficient to prevent having stack adjacent to a different mapping.
But this seems to be insufficient in the light of the stack usage in
userspace. E.g. glibc uses as large as 64kB alloca() in many commonly
used functions. Others use constructs liks gid_t buffer[NGROUPS_MAX]
which is 256kB or stack strings with MAX_ARG_STRLEN.

This will become especially dangerous for suid binaries and the default
no limit for the stack size limit because those applications can be
tricked to consume a large portion of the stack and a single glibc call
could jump over the guard page. These attacks are not theoretical,
unfortunatelly.

Make those attacks less probable by increasing the stack guard gap
to 1MB (on systems with 4k pages; but make it depend on the page size
because systems with larger base pages might cap stack allocations in
the PAGE_SIZE units) which should cover larger alloca() and VLA stack
allocations. It is obviously not a full fix because the problem is
somehow inherent, but it should reduce attack space a lot.

One could argue that the gap size should be configurable from userspace,
but that can be done later when somebody finds that the new 1MB is wrong
for some special case applications.  For now, add a kernel command line
option (stack_guard_gap) to specify the stack gap size (in page units).

Implementation wise, first delete all the old code for stack guard page:
because although we could get away with accounting one extra page in a
stack vma, accounting a larger gap can break userspace - case in point,
a program run with "ulimit -S -v 20000" failed when the 1MB gap was
counted for RLIMIT_AS; similar problems could come with RLIMIT_MLOCK
and strict non-overcommit mode.

Instead of keeping gap inside the stack vma, maintain the stack guard
gap as a gap between vmas: using vm_start_gap() in place of vm_start
(or vm_end_gap() in place of vm_end if VM_GROWSUP) in just those few
places which need to respect the gap - mainly arch_get_unmapped_area(),
and and the vma tree's subtree_gap support for that.

Original-patch-by: Oleg Nesterov <oleg@redhat.com>
Original-patch-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Tested-by: Helge Deller <deller@gmx.de> # parisc
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-06-19 21:50:20 +08:00