Commit graph

876893 commits

Author SHA1 Message Date
Bart Van Assche
d92e714a46 scsi: Revert "RDMA/isert: Fix a recently introduced regression related to logout"
commit 76261ada16 upstream.

Since commit 04060db411 introduces soft lockups when toggling network
interfaces, revert it.

Link: https://marc.info/?l=target-devel&m=158157054906196
Cc: Rahul Kundu <rahul.kundu@chelsio.com>
Cc: Mike Marciniszyn <mike.marciniszyn@intel.com>
Cc: Sagi Grimberg <sagi@grimberg.me>
Reported-by: Dakshaja Uppalapati <dakshaja@chelsio.com>
Fixes: 04060db411 ("scsi: RDMA/isert: Fix a recently introduced regression related to logout")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:25 +01:00
Rob Clark
42b4f3c8ec drm/msm/dpu: fix BGR565 vs RGB565 confusion
commit 8fc7036ee6 upstream.

The component order between the two was swapped, resulting in incorrect
color when games with 565 visual hit the overlay path instead of GPU
composition.

Fixes: 25fdd5933e ("drm/msm: Add SDM845 DPU support")
Signed-off-by: Rob Clark <robdclark@chromium.org>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Rob Clark <robdclark@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:25 +01:00
Chris Wilson
337cbf3ea8 drm/i915/gt: Protect defer_request() from new waiters
commit 19b5f3b419 upstream.

Mika spotted

<4>[17436.705441] general protection fault: 0000 [#1] PREEMPT SMP PTI
<4>[17436.705447] CPU: 2 PID: 0 Comm: swapper/2 Not tainted 5.5.0+ #1
<4>[17436.705449] Hardware name: System manufacturer System Product Name/Z170M-PLUS, BIOS 3805 05/16/2018
<4>[17436.705512] RIP: 0010:__execlists_submission_tasklet+0xc4d/0x16e0 [i915]
<4>[17436.705516] Code: c5 4c 8d 60 e0 75 17 e9 8c 07 00 00 49 8b 44 24 20 49 39 c5 4c 8d 60 e0 0f 84 7a 07 00 00 49 8b 5c 24 08 49 8b 87 80 00 00 00 <48> 39 83 d8 fe ff ff 75 d9 48 8b 83 88 fe ff ff a8 01 0f 84 b6 05
<4>[17436.705518] RSP: 0018:ffffc9000012ce80 EFLAGS: 00010083
<4>[17436.705521] RAX: ffff88822ae42000 RBX: 5a5a5a5a5a5a5a5a RCX: dead000000000122
<4>[17436.705523] RDX: ffff88822ae42588 RSI: ffff8881e32a7908 RDI: ffff8881c429fd48
<4>[17436.705525] RBP: ffffc9000012cf00 R08: ffff88822ae42588 R09: 00000000fffffffe
<4>[17436.705527] R10: ffff8881c429fb80 R11: 00000000a677cf08 R12: ffff8881c42a0aa8
<4>[17436.705529] R13: ffff8881c429fd38 R14: ffff88822ae42588 R15: ffff8881c429fb80
<4>[17436.705532] FS:  0000000000000000(0000) GS:ffff88822ed00000(0000) knlGS:0000000000000000
<4>[17436.705534] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
<4>[17436.705536] CR2: 00007f858c76d000 CR3: 0000000005610003 CR4: 00000000003606e0
<4>[17436.705538] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
<4>[17436.705540] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
<4>[17436.705542] Call Trace:
<4>[17436.705545]  <IRQ>
<4>[17436.705603]  execlists_submission_tasklet+0xc0/0x130 [i915]

which is us consuming a partially initialised new waiter in
defer_requests(). We can prevent this by initialising the i915_dependency
prior to making it visible, and since we are using a concurrent
list_add/iterator mark them up to the compiler.

Fixes: 8ee36e048c ("drm/i915/execlists: Minimalistic timeslicing")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200206204915.2636606-2-chris@chris-wilson.co.uk
(cherry picked from commit f14f27b166)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:25 +01:00
Tomi Valkeinen
93805d430c drm/bridge: tc358767: fix poll timeouts
commit 8a6483ac63 upstream.

Link training fails with:

  Link training timeout waiting for LT_LOOPDONE!
  main link enable error: -110

This is caused by too tight timeouts, which were changed recently in
aa92213f38 ("drm/bridge: tc358767: Simplify polling in tc_link_training()").

With a quick glance, the commit does not change the timeouts. However,
the method of delaying/sleeping is different, and as the timeout in the
previous implementation was not explicit, the new version in practice
has much tighter timeout.

The same change was made to other parts in the driver, but the link
training timeout is the only one I have seen causing issues.
Nevertheless, 1 us sleep is not very sane, and the timeouts look pretty
tight, so lets fix all the timeouts.

One exception was the aux busy poll, where the poll sleep was much
longer than necessary (or optimal).

I measured the times on my setup, and now the sleep times are set to
such values that they result in multiple loops, but not too many (say,
5-10 loops). The timeouts were all increased to 100ms, which should be
more than enough for all of these, but in case of bad errors, shouldn't
stop the driver as multi-second timeouts could do.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Fixes: aa92213f38 ("drm/bridge: tc358767: Simplify polling in tc_link_training()")
Tested-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191209082707.24531-1-tomi.valkeinen@ti.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:25 +01:00
Igor Druzhinin
7de50906e7 drm/i915/gvt: more locking for ppgtt mm LRU list
commit 0e9d7bb293 upstream.

When the lock was introduced in commit 72aabfb862 ("drm/i915/gvt: Add mutual
lock for ppgtt mm LRU list") one place got lost.

Fixes: 72aabfb862 ("drm/i915/gvt: Add mutual lock for ppgtt mm LRU list")
Signed-off-by: Igor Druzhinin <igor.druzhinin@citrix.com>
Reviewed-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1580742421-25194-1-git-send-email-igor.druzhinin@citrix.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:25 +01:00
Chris Wilson
19f8fb2731 drm/i915/execlists: Always force a context reload when rewinding RING_TAIL
commit b1339ecac6 upstream.

If we rewind the RING_TAIL on a context, due to a preemption event, we
must force the context restore for the RING_TAIL update to be properly
handled. Rather than note which preemption events may cause us to rewind
the tail, compare the new request's tail with the previously submitted
RING_TAIL, as it turns out that timeslicing was causing unexpected
rewinds.

   <idle>-0       0d.s2 1280851190us : __execlists_submission_tasklet: 0000:00:02.0 rcs0: expired last=130:4698, prio=3, hint=3
   <idle>-0       0d.s2 1280851192us : __i915_request_unsubmit: 0000:00:02.0 rcs0: fence 66:119966, current 119964
   <idle>-0       0d.s2 1280851195us : __i915_request_unsubmit: 0000:00:02.0 rcs0: fence 130:4698, current 4695
   <idle>-0       0d.s2 1280851198us : __i915_request_unsubmit: 0000:00:02.0 rcs0: fence 130:4696, current 4695
^----  Note we unwind 2 requests from the same context

   <idle>-0       0d.s2 1280851208us : __i915_request_submit: 0000:00:02.0 rcs0: fence 130:4696, current 4695
   <idle>-0       0d.s2 1280851213us : __i915_request_submit: 0000:00:02.0 rcs0: fence 134:1508, current 1506
^---- But to apply the new timeslice, we have to replay the first request
      before the new client can start -- the unexpected RING_TAIL rewind

   <idle>-0       0d.s2 1280851219us : trace_ports: 0000:00:02.0 rcs0: submit { 130:4696*, 134:1508 }
 synmark2-5425    2..s. 1280851239us : process_csb: 0000:00:02.0 rcs0: cs-irq head=5, tail=0
 synmark2-5425    2..s. 1280851240us : process_csb: 0000:00:02.0 rcs0: csb[0]: status=0x00008002:0x00000000
^---- Preemption event for the ELSP update; note the lite-restore

 synmark2-5425    2..s. 1280851243us : trace_ports: 0000:00:02.0 rcs0: preempted { 130:4698, 66:119966 }
 synmark2-5425    2..s. 1280851246us : trace_ports: 0000:00:02.0 rcs0: promote { 130:4696*, 134:1508 }
 synmark2-5425    2.... 1280851462us : __i915_request_commit: 0000:00:02.0 rcs0: fence 130:4700, current 4695
 synmark2-5425    2.... 1280852111us : __i915_request_commit: 0000:00:02.0 rcs0: fence 130:4702, current 4695
 synmark2-5425    2.Ns1 1280852296us : process_csb: 0000:00:02.0 rcs0: cs-irq head=0, tail=2
 synmark2-5425    2.Ns1 1280852297us : process_csb: 0000:00:02.0 rcs0: csb[1]: status=0x00000814:0x00000000
 synmark2-5425    2.Ns1 1280852299us : trace_ports: 0000:00:02.0 rcs0: completed { 130:4696!, 134:1508 }
 synmark2-5425    2.Ns1 1280852301us : process_csb: 0000:00:02.0 rcs0: csb[2]: status=0x00000818:0x00000040
 synmark2-5425    2.Ns1 1280852302us : trace_ports: 0000:00:02.0 rcs0: completed { 134:1508, 0:0 }
 synmark2-5425    2.Ns1 1280852313us : process_csb: process_csb:2336 GEM_BUG_ON(!i915_request_completed(*execlists->active) && !reset_in_progress(execlists))

Fixes: 8ee36e048c ("drm/i915/execlists: Minimalistic timeslicing")
Referenecs: 82c69bf586 ("drm/i915/gt: Detect if we miss WaIdleLiteRestore")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: <stable@vger.kernel.org> # v5.4+
Link: https://patchwork.freedesktop.org/patch/msgid/20200207211452.2860634-1-chris@chris-wilson.co.uk
(cherry picked from commit 5ba32c7be8)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:25 +01:00
Chris Wilson
1e0175a154 drm/i915/gt: Detect if we miss WaIdleLiteRestore
commit 82c69bf586 upstream.

In order to avoid confusing the HW, we must never submit an empty ring
during lite-restore, that is we should always advance the RING_TAIL
before submitting to stay ahead of the RING_HEAD.

Normally this is prevented by keeping a couple of spare NOPs in the
request->wa_tail so that on resubmission we can advance the tail. This
relies on the request only being resubmitted once, which is the normal
condition as it is seen once for ELSP[1] and then later in ELSP[0]. On
preemption, the requests are unwound and the tail reset back to the
normal end point (as we know the request is incomplete and therefore its
RING_HEAD is even earlier).

However, if this w/a should fail we would try and resubmit the request
with the RING_TAIL already set to the location of this request's wa_tail
potentially causing a GPU hang. We can spot when we do try and
incorrectly resubmit without advancing the RING_TAIL and spare any
embarrassment by forcing the context restore.

In the case of preempt-to-busy, we leave the requests running on the HW
while we unwind. As the ring is still live, we cannot rewind our
rq->tail without forcing a reload so leave it set to rq->wa_tail and
only force a reload if we resubmit after a lite-restore. (Normally, the
forced reload will be a part of the preemption event.)

Fixes: 22b7a426bb ("drm/i915/execlists: Preempt-to-busy")
Closes: https://gitlab.freedesktop.org/drm/intel/issues/673
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: stable@kernel.vger.org
Link: https://patchwork.freedesktop.org/patch/msgid/20191209023215.3519970-1-chris@chris-wilson.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:25 +01:00
Greg Kroah-Hartman
341c8e03a9 Revert "dmaengine: imx-sdma: Fix memory leak"
This reverts commit 8a7aa4feea which is
commit 02939cd167 upstream.

Andreas writes:
	This patch breaks our imx6 board with the attached trace.
	Reverting the patch makes it boot again.

Reported-by: Andreas Tobler <andreas.tobler@onway.ch>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Robin Gong <yibin.gong@nxp.com>
Cc: Vinod Koul <vkoul@kernel.org>
Cc: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:24 +01:00
Filipe Manana
9ad7f8df34 Btrfs: fix deadlock during fast fsync when logging prealloc extents beyond eof
commit a5ae50dea9 upstream.

While logging the prealloc extents of an inode during a fast fsync we call
btrfs_truncate_inode_items(), through btrfs_log_prealloc_extents(), while
holding a read lock on a leaf of the inode's root (not the log root, the
fs/subvol root), and then that function locks the file range in the inode's
iotree. This can lead to a deadlock when:

* the fsync is ranged

* the file has prealloc extents beyond eof

* writeback for a range different from the fsync range starts
  during the fsync

* the size of the file is not sector size aligned

Because when finishing an ordered extent we lock first a file range and
then try to COW the fs/subvol tree to insert an extent item.

The following diagram shows how the deadlock can happen.

           CPU 1                                        CPU 2

  btrfs_sync_file()
    --> for range [0, 1MiB)

    --> inode has a size of
        1MiB and has 1 prealloc
        extent beyond the
        i_size, starting at offset
        4MiB

    flushes all delalloc for the
    range [0MiB, 1MiB) and waits
    for the respective ordered
    extents to complete

                                              --> before task at CPU 1 locks the
                                                  inode, a write into file range
                                                  [1MiB, 2MiB + 1KiB) is made

                                              --> i_size is updated to 2MiB + 1KiB

                                              --> writeback is started for that
                                                  range, [1MiB, 2MiB + 4KiB)
                                                  --> end offset rounded up to
                                                      be sector size aligned

    btrfs_log_dentry_safe()
      btrfs_log_inode_parent()
        btrfs_log_inode()

          btrfs_log_changed_extents()
            btrfs_log_prealloc_extents()
              --> does a search on the
                  inode's root
              --> holds a read lock on
                  leaf X

                                              btrfs_finish_ordered_io()
                                                --> locks range [1MiB, 2MiB + 4KiB)
                                                    --> end offset rounded up
                                                        to be sector size aligned

                                                --> tries to cow leaf X, through
                                                    insert_reserved_file_extent()
                                                    --> already locked by the
                                                        task at CPU 1

              btrfs_truncate_inode_items()

                --> gets an i_size of
                    2MiB + 1KiB, which is
                    not sector size
                    aligned

                --> tries to lock file
                    range [2MiB, (u64)-1)
                    --> the start range
                        is rounded down
                        from 2MiB + 1K
                        to 2MiB to be sector
                        size aligned

                    --> but the subrange
                        [2MiB, 2MiB + 4KiB) is
                        already locked by
                        task at CPU 2 which
                        is waiting to get a
                        write lock on leaf X
                        for which we are
                        holding a read lock

                                *** deadlock ***

This results in a stack trace like the following, triggered by test case
generic/561 from fstests:

  [ 2779.973608] INFO: task kworker/u8:6:247 blocked for more than 120 seconds.
  [ 2779.979536]       Not tainted 5.6.0-rc2-btrfs-next-53 #1
  [ 2779.984503] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [ 2779.990136] kworker/u8:6    D    0   247      2 0x80004000
  [ 2779.990457] Workqueue: btrfs-endio-write btrfs_work_helper [btrfs]
  [ 2779.990466] Call Trace:
  [ 2779.990491]  ? __schedule+0x384/0xa30
  [ 2779.990521]  schedule+0x33/0xe0
  [ 2779.990616]  btrfs_tree_read_lock+0x19e/0x2e0 [btrfs]
  [ 2779.990632]  ? remove_wait_queue+0x60/0x60
  [ 2779.990730]  btrfs_read_lock_root_node+0x2f/0x40 [btrfs]
  [ 2779.990782]  btrfs_search_slot+0x510/0x1000 [btrfs]
  [ 2779.990869]  btrfs_lookup_file_extent+0x4a/0x70 [btrfs]
  [ 2779.990944]  __btrfs_drop_extents+0x161/0x1060 [btrfs]
  [ 2779.990987]  ? mark_held_locks+0x6d/0xc0
  [ 2779.990994]  ? __slab_alloc.isra.49+0x99/0x100
  [ 2779.991060]  ? insert_reserved_file_extent.constprop.19+0x64/0x300 [btrfs]
  [ 2779.991145]  insert_reserved_file_extent.constprop.19+0x97/0x300 [btrfs]
  [ 2779.991222]  ? start_transaction+0xdd/0x5c0 [btrfs]
  [ 2779.991291]  btrfs_finish_ordered_io+0x4f4/0x840 [btrfs]
  [ 2779.991405]  btrfs_work_helper+0xaa/0x720 [btrfs]
  [ 2779.991432]  process_one_work+0x26d/0x6a0
  [ 2779.991460]  worker_thread+0x4f/0x3e0
  [ 2779.991481]  ? process_one_work+0x6a0/0x6a0
  [ 2779.991489]  kthread+0x103/0x140
  [ 2779.991499]  ? kthread_create_worker_on_cpu+0x70/0x70
  [ 2779.991515]  ret_from_fork+0x3a/0x50
  (...)
  [ 2780.026211] INFO: task fsstress:17375 blocked for more than 120 seconds.
  [ 2780.027480]       Not tainted 5.6.0-rc2-btrfs-next-53 #1
  [ 2780.028482] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [ 2780.030035] fsstress        D    0 17375  17373 0x00004000
  [ 2780.030038] Call Trace:
  [ 2780.030044]  ? __schedule+0x384/0xa30
  [ 2780.030052]  schedule+0x33/0xe0
  [ 2780.030075]  lock_extent_bits+0x20c/0x320 [btrfs]
  [ 2780.030094]  ? btrfs_truncate_inode_items+0xf4/0x1150 [btrfs]
  [ 2780.030098]  ? rcu_read_lock_sched_held+0x59/0xa0
  [ 2780.030102]  ? remove_wait_queue+0x60/0x60
  [ 2780.030122]  btrfs_truncate_inode_items+0x133/0x1150 [btrfs]
  [ 2780.030151]  ? btrfs_set_path_blocking+0xb2/0x160 [btrfs]
  [ 2780.030165]  ? btrfs_search_slot+0x379/0x1000 [btrfs]
  [ 2780.030195]  btrfs_log_changed_extents.isra.8+0x841/0x93e [btrfs]
  [ 2780.030202]  ? do_raw_spin_unlock+0x49/0xc0
  [ 2780.030215]  ? btrfs_get_num_csums+0x10/0x10 [btrfs]
  [ 2780.030239]  btrfs_log_inode+0xf83/0x1124 [btrfs]
  [ 2780.030251]  ? __mutex_unlock_slowpath+0x45/0x2a0
  [ 2780.030275]  btrfs_log_inode_parent+0x2a0/0xe40 [btrfs]
  [ 2780.030282]  ? dget_parent+0xa1/0x370
  [ 2780.030309]  btrfs_log_dentry_safe+0x4a/0x70 [btrfs]
  [ 2780.030329]  btrfs_sync_file+0x3f3/0x490 [btrfs]
  [ 2780.030339]  do_fsync+0x38/0x60
  [ 2780.030343]  __x64_sys_fdatasync+0x13/0x20
  [ 2780.030345]  do_syscall_64+0x5c/0x280
  [ 2780.030348]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
  [ 2780.030356] RIP: 0033:0x7f2d80f6d5f0
  [ 2780.030361] Code: Bad RIP value.
  [ 2780.030362] RSP: 002b:00007ffdba3c8548 EFLAGS: 00000246 ORIG_RAX: 000000000000004b
  [ 2780.030364] RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f2d80f6d5f0
  [ 2780.030365] RDX: 00007ffdba3c84b0 RSI: 00007ffdba3c84b0 RDI: 0000000000000003
  [ 2780.030367] RBP: 000000000000004a R08: 0000000000000001 R09: 00007ffdba3c855c
  [ 2780.030368] R10: 0000000000000078 R11: 0000000000000246 R12: 00000000000001f4
  [ 2780.030369] R13: 0000000051eb851f R14: 00007ffdba3c85f0 R15: 0000557a49220d90

So fix this by making btrfs_truncate_inode_items() not lock the range in
the inode's iotree when the target root is a log root, since it's not
needed to lock the range for log roots as the protection from the inode's
lock and log_mutex are all that's needed.

Fixes: 28553fa992 ("Btrfs: fix race between shrinking truncate and fiemap")
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:24 +01:00
Josef Bacik
73e1f26632 btrfs: don't set path->leave_spinning for truncate
commit 52e29e3310 upstream.

The only time we actually leave the path spinning is if we're truncating
a small amount and don't actually free an extent, which is not a common
occurrence.  We have to set the path blocking in order to add the
delayed ref anyway, so the first extent we find we set the path to
blocking and stay blocking for the duration of the operation.  With the
upcoming file extent map stuff there will be another case that we have
to have the path blocking, so just swap to blocking always.

Note: this patch also fixes a warning after 28553fa992 ("Btrfs: fix
race between shrinking truncate and fiemap") got merged that inserts
extent locks around truncation so the path must not leave spinning locks
after btrfs_search_slot.

  [70.794783] BUG: sleeping function called from invalid context at mm/slab.h:565
  [70.794834] in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 1141, name: rsync
  [70.794863] 5 locks held by rsync/1141:
  [70.794876]  #0: ffff888417b9c408 (sb_writers#17){.+.+}, at: mnt_want_write+0x20/0x50
  [70.795030]  #1: ffff888428de28e8 (&type->i_mutex_dir_key#13/1){+.+.}, at: lock_rename+0xf1/0x100
  [70.795051]  #2: ffff888417b9c608 (sb_internal#2){.+.+}, at: start_transaction+0x394/0x560
  [70.795124]  #3: ffff888403081768 (btrfs-fs-01){++++}, at: btrfs_try_tree_write_lock+0x2f/0x160
  [70.795203]  #4: ffff888403086568 (btrfs-fs-00){++++}, at: btrfs_try_tree_write_lock+0x2f/0x160
  [70.795222] CPU: 5 PID: 1141 Comm: rsync Not tainted 5.6.0-rc2-backup+ #2
  [70.795362] Call Trace:
  [70.795374]  dump_stack+0x71/0xa0
  [70.795445]  ___might_sleep.part.96.cold.106+0xa6/0xb6
  [70.795459]  kmem_cache_alloc+0x1d3/0x290
  [70.795471]  alloc_extent_state+0x22/0x1c0
  [70.795544]  __clear_extent_bit+0x3ba/0x580
  [70.795557]  ? _raw_spin_unlock_irq+0x24/0x30
  [70.795569]  btrfs_truncate_inode_items+0x339/0xe50
  [70.795647]  btrfs_evict_inode+0x269/0x540
  [70.795659]  ? dput.part.38+0x29/0x460
  [70.795671]  evict+0xcd/0x190
  [70.795682]  __dentry_kill+0xd6/0x180
  [70.795754]  dput.part.38+0x2ad/0x460
  [70.795765]  do_renameat2+0x3cb/0x540
  [70.795777]  __x64_sys_rename+0x1c/0x20

Reported-by: Dave Jones <davej@codemonkey.org.uk>
Fixes: 28553fa992 ("Btrfs: fix race between shrinking truncate and fiemap")
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ add note ]
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:24 +01:00
Filipe Manana
d3d0fb9d42 Btrfs: fix race between shrinking truncate and fiemap
commit 28553fa992 upstream.

When there is a fiemap executing in parallel with a shrinking truncate
we can end up in a situation where we have extent maps for which we no
longer have corresponding file extent items. This is generally harmless
and at the moment the only consequences are missing file extent items
representing holes after we expand the file size again after the
truncate operation removed the prealloc extent items, and stale
information for future fiemap calls (reporting extents that no longer
exist or may have been reallocated to other files for example).

Consider the following example:

1) Our inode has a size of 128KiB, one 128KiB extent at file offset 0
   and a 1MiB prealloc extent at file offset 128KiB;

2) Task A starts doing a shrinking truncate of our inode to reduce it to
   a size of 64KiB. Before it searches the subvolume tree for file
   extent items to delete, it drops all the extent maps in the range
   from 64KiB to (u64)-1 by calling btrfs_drop_extent_cache();

3) Task B starts doing a fiemap against our inode. When looking up for
   the inode's extent maps in the range from 128KiB to (u64)-1, it
   doesn't find any in the inode's extent map tree, since they were
   removed by task A.  Because it didn't find any in the extent map
   tree, it scans the inode's subvolume tree for file extent items, and
   it finds the 1MiB prealloc extent at file offset 128KiB, then it
   creates an extent map based on that file extent item and adds it to
   inode's extent map tree (this ends up being done by
   btrfs_get_extent() <- btrfs_get_extent_fiemap() <-
   get_extent_skip_holes());

4) Task A then drops the prealloc extent at file offset 128KiB and
   shrinks the 128KiB extent file offset 0 to a length of 64KiB. The
   truncation operation finishes and we end up with an extent map
   representing a 1MiB prealloc extent at file offset 128KiB, despite we
   don't have any more that extent;

After this the two types of problems we have are:

1) Future calls to fiemap always report that a 1MiB prealloc extent
   exists at file offset 128KiB. This is stale information, no longer
   correct;

2) If the size of the file is increased, by a truncate operation that
   increases the file size or by a write into a file offset > 64KiB for
   example, we end up not inserting file extent items to represent holes
   for any range between 128KiB and 128KiB + 1MiB, since the hole
   expansion function, btrfs_cont_expand() will skip hole insertion for
   any range for which an extent map exists that represents a prealloc
   extent. This causes fsck to complain about missing file extent items
   when not using the NO_HOLES feature.

The second issue could be often triggered by test case generic/561 from
fstests, which runs fsstress and duperemove in parallel, and duperemove
does frequent fiemap calls.

Essentially the problems happens because fiemap does not acquire the
inode's lock while truncate does, and fiemap locks the file range in the
inode's iotree while truncate does not. So fix the issue by making
btrfs_truncate_inode_items() lock the file range from the new file size
to (u64)-1, so that it serializes with fiemap.

CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:24 +01:00
Filipe Manana
c383f8ad2a Btrfs: fix btrfs_wait_ordered_range() so that it waits for all ordered extents
commit e75fd33b3f upstream.

In btrfs_wait_ordered_range() once we find an ordered extent that has
finished with an error we exit the loop and don't wait for any other
ordered extents that might be still in progress.

All the users of btrfs_wait_ordered_range() expect that there are no more
ordered extents in progress after that function returns. So past fixes
such like the ones from the two following commits:

  ff612ba784 ("btrfs: fix panic during relocation after ENOSPC before
                   writeback happens")

  28aeeac1dd ("Btrfs: fix panic when starting bg cache writeout after
                   IO error")

don't work when there are multiple ordered extents in the range.

Fix that by making btrfs_wait_ordered_range() wait for all ordered extents
even after it finds one that had an error.

Link: https://github.com/kdave/btrfs-progs/issues/228#issuecomment-569777554
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:24 +01:00
Josef Bacik
9af8e25889 btrfs: do not check delayed items are empty for single transaction cleanup
commit 1e90315149 upstream.

btrfs_assert_delayed_root_empty() will check if the delayed root is
completely empty, but this is a filesystem-wide check.  On cleanup we
may have allowed other transactions to begin, for whatever reason, and
thus the delayed root is not empty.

So remove this check from cleanup_one_transation().  This however can
stay in btrfs_cleanup_transaction(), because it checks only after all of
the transactions have been properly cleaned up, and thus is valid.

CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:24 +01:00
Josef Bacik
6065ca5d01 btrfs: reset fs_root to NULL on error in open_ctree
commit 315bf8ef91 upstream.

While running my error injection script I hit a panic when we tried to
clean up the fs_root when freeing the fs_root.  This is because
fs_info->fs_root == PTR_ERR(-EIO), which isn't great.  Fix this by
setting fs_info->fs_root = NULL; if we fail to read the root.

CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:24 +01:00
Josef Bacik
37a2e70480 btrfs: fix bytes_may_use underflow in prealloc error condtition
commit b778cf962d upstream.

I hit the following warning while running my error injection stress
testing:

  WARNING: CPU: 3 PID: 1453 at fs/btrfs/space-info.h:108 btrfs_free_reserved_data_space_noquota+0xfd/0x160 [btrfs]
  RIP: 0010:btrfs_free_reserved_data_space_noquota+0xfd/0x160 [btrfs]
  Call Trace:
  btrfs_free_reserved_data_space+0x4f/0x70 [btrfs]
  __btrfs_prealloc_file_range+0x378/0x470 [btrfs]
  elfcorehdr_read+0x40/0x40
  ? elfcorehdr_read+0x40/0x40
  ? btrfs_commit_transaction+0xca/0xa50 [btrfs]
  ? dput+0xb4/0x2a0
  ? btrfs_log_dentry_safe+0x55/0x70 [btrfs]
  ? btrfs_sync_file+0x30e/0x420 [btrfs]
  ? do_fsync+0x38/0x70
  ? __x64_sys_fdatasync+0x13/0x20
  ? do_syscall_64+0x5b/0x1b0
  ? entry_SYSCALL_64_after_hwframe+0x44/0xa9

This happens if we fail to insert our reserved file extent.  At this
point we've already converted our reservation from ->bytes_may_use to
->bytes_reserved.  However once we break we will attempt to free
everything from [cur_offset, end] from ->bytes_may_use, but our extent
reservation will overlap part of this.

Fix this problem by adding ins.offset (our extent allocation size) to
cur_offset so we remove the actual remaining part from ->bytes_may_use.

I validated this fix using my inject-error.py script

python inject-error.py -o should_fail_bio -t cache_save_setup -t \
	__btrfs_prealloc_file_range \
	-t insert_reserved_file_extent.constprop.0 \
	-r "-5" ./run-fsstress.sh

where run-fsstress.sh simply mounts and runs fsstress on a disk.

CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:24 +01:00
Jeff Mahoney
40ea30638d btrfs: destroy qgroup extent records on transaction abort
commit 81f7eb00ff upstream.

We clean up the delayed references when we abort a transaction but we
leave the pending qgroup extent records behind, leaking memory.

This patch destroys the extent records when we destroy the delayed refs
and makes sure ensure they're gone before releasing the transaction.

Fixes: 3368d001ba ("btrfs: qgroup: Record possible quota-related extent for qgroup.")
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
[ Rebased to latest upstream, remove to_qgroup() helper, use
  rbtree_postorder_for_each_entry_safe() wrapper ]
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:23 +01:00
Miaohe Lin
7e946e30a4 KVM: apic: avoid calculating pending eoi from an uninitialized val
commit 23520b2def upstream.

When pv_eoi_get_user() fails, 'val' may remain uninitialized and the return
value of pv_eoi_get_pending() becomes random. Fix the issue by initializing
the variable.

Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:23 +01:00
Vitaly Kuznetsov
dc5537061b KVM: nVMX: handle nested posted interrupts when apicv is disabled for L1
commit 91a5f413af upstream.

Even when APICv is disabled for L1 it can (and, actually, is) still
available for L2, this means we need to always call
vmx_deliver_nested_posted_interrupt() when attempting an interrupt
delivery.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:23 +01:00
Vitaly Kuznetsov
16f8553f75 KVM: nVMX: clear PIN_BASED_POSTED_INTR from nested pinbased_ctls only when apicv is globally disabled
commit a444326780 upstream.

When apicv is disabled on a vCPU (e.g. by enabling KVM_CAP_HYPERV_SYNIC*),
nothing happens to VMX MSRs on the already existing vCPUs, however, all new
ones are created with PIN_BASED_POSTED_INTR filtered out. This is very
confusing and results in the following picture inside the guest:

$ rdmsr -ax 0x48d
ff00000016
7f00000016
7f00000016
7f00000016

This is observed with QEMU and 4-vCPU guest: QEMU creates vCPU0, does
KVM_CAP_HYPERV_SYNIC2 and then creates the remaining three.

L1 hypervisor may only check CPU0's controls to find out what features
are available and it will be very confused later. Switch to setting
PIN_BASED_POSTED_INTR control based on global 'enable_apicv' setting.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:23 +01:00
Oliver Upton
0f042f5e98 KVM: nVMX: Check IO instruction VM-exit conditions
commit 35a571346a upstream.

Consult the 'unconditional IO exiting' and 'use IO bitmaps' VM-execution
controls when checking instruction interception. If the 'use IO bitmaps'
VM-execution control is 1, check the instruction access against the IO
bitmaps to determine if the instruction causes a VM-exit.

Signed-off-by: Oliver Upton <oupton@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:23 +01:00
Oliver Upton
c4064f14f7 KVM: nVMX: Refactor IO bitmap checks into helper function
commit e71237d3ff upstream.

Checks against the IO bitmap are useful for both instruction emulation
and VM-exit reflection. Refactor the IO bitmap checks into a helper
function.

Signed-off-by: Oliver Upton <oupton@google.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:23 +01:00
Eric Biggers
e5d25003d0 ext4: fix race between writepages and enabling EXT4_EXTENTS_FL
commit cb85f4d23f upstream.

If EXT4_EXTENTS_FL is set on an inode while ext4_writepages() is running
on it, the following warning in ext4_add_complete_io() can be hit:

WARNING: CPU: 1 PID: 0 at fs/ext4/page-io.c:234 ext4_put_io_end_defer+0xf0/0x120

Here's a minimal reproducer (not 100% reliable) (root isn't required):

        while true; do
                sync
        done &
        while true; do
                rm -f file
                touch file
                chattr -e file
                echo X >> file
                chattr +e file
        done

The problem is that in ext4_writepages(), ext4_should_dioread_nolock()
(which only returns true on extent-based files) is checked once to set
the number of reserved journal credits, and also again later to select
the flags for ext4_map_blocks() and copy the reserved journal handle to
ext4_io_end::handle.  But if EXT4_EXTENTS_FL is being concurrently set,
the first check can see dioread_nolock disabled while the later one can
see it enabled, causing the reserved handle to unexpectedly be NULL.

Since changing EXT4_EXTENTS_FL is uncommon, and there may be other races
related to doing so as well, fix this by synchronizing changing
EXT4_EXTENTS_FL with ext4_writepages() via the existing
s_writepages_rwsem (previously called s_journal_flag_rwsem).

This was originally reported by syzbot without a reproducer at
https://syzkaller.appspot.com/bug?extid=2202a584a00fffd19fbf,
but now that dioread_nolock is the default I also started seeing this
when running syzkaller locally.

Link: https://lore.kernel.org/r/20200219183047.47417-3-ebiggers@kernel.org
Reported-by: syzbot+2202a584a00fffd19fbf@syzkaller.appspotmail.com
Fixes: 6b523df4fb ("ext4: use transaction reservation for extent conversion in ext4_end_io")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:23 +01:00
Eric Biggers
5195dc6e93 ext4: rename s_journal_flag_rwsem to s_writepages_rwsem
commit bbd55937de upstream.

In preparation for making s_journal_flag_rwsem synchronize
ext4_writepages() with changes to both the EXTENTS and JOURNAL_DATA
flags (rather than just JOURNAL_DATA as it does currently), rename it to
s_writepages_rwsem.

Link: https://lore.kernel.org/r/20200219183047.47417-2-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:23 +01:00
Jan Kara
6ccdd6616a ext4: fix mount failure with quota configured as module
commit 9db176bceb upstream.

When CONFIG_QFMT_V2 is configured as a module, the test in
ext4_feature_set_ok() fails and so mount of filesystems with quota or
project features fails. Fix the test to use IS_ENABLED macro which
works properly even for modules.

Link: https://lore.kernel.org/r/20200221100835.9332-1-jack@suse.cz
Fixes: d65d87a074 ("ext4: improve explanation of a mount failure caused by a misconfigured kernel")
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:22 +01:00
Suraj Jitindar Singh
eac2bb1042 ext4: fix potential race between s_flex_groups online resizing and access
commit 7c990728b9 upstream.

During an online resize an array of s_flex_groups structures gets replaced
so it can get enlarged. If there is a concurrent access to the array and
this memory has been reused then this can lead to an invalid memory access.

The s_flex_group array has been converted into an array of pointers rather
than an array of structures. This is to ensure that the information
contained in the structures cannot get out of sync during a resize due to
an accessor updating the value in the old structure after it has been
copied but before the array pointer is updated. Since the structures them-
selves are no longer copied but only the pointers to them this case is
mitigated.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=206443
Link: https://lore.kernel.org/r/20200221053458.730016-4-tytso@mit.edu
Signed-off-by: Suraj Jitindar Singh <surajjs@amazon.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:22 +01:00
Suraj Jitindar Singh
58631f8cbc ext4: fix potential race between s_group_info online resizing and access
commit df3da4ea5a upstream.

During an online resize an array of pointers to s_group_info gets replaced
so it can get enlarged. If there is a concurrent access to the array in
ext4_get_group_info() and this memory has been reused then this can lead to
an invalid memory access.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=206443
Link: https://lore.kernel.org/r/20200221053458.730016-3-tytso@mit.edu
Signed-off-by: Suraj Jitindar Singh <surajjs@amazon.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Balbir Singh <sblbir@amazon.com>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:22 +01:00
Theodore Ts'o
bb43897de9 ext4: fix potential race between online resizing and write operations
commit 1d0c3924a9 upstream.

During an online resize an array of pointers to buffer heads gets
replaced so it can get enlarged.  If there is a racing block
allocation or deallocation which uses the old array, and the old array
has gotten reused this can lead to a GPF or some other random kernel
memory getting modified.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=206443
Link: https://lore.kernel.org/r/20200221053458.730016-2-tytso@mit.edu
Reported-by: Suraj Jitindar Singh <surajjs@amazon.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:22 +01:00
Shijie Luo
ded8c21ac4 ext4: add cond_resched() to __ext4_find_entry()
commit 9424ef56e1 upstream.

We tested a soft lockup problem in linux 4.19 which could also
be found in linux 5.x.

When dir inode takes up a large number of blocks, and if the
directory is growing when we are searching, it's possible the
restart branch could be called many times, and the do while loop
could hold cpu a long time.

Here is the call trace in linux 4.19.

[  473.756186] Call trace:
[  473.756196]  dump_backtrace+0x0/0x198
[  473.756199]  show_stack+0x24/0x30
[  473.756205]  dump_stack+0xa4/0xcc
[  473.756210]  watchdog_timer_fn+0x300/0x3e8
[  473.756215]  __hrtimer_run_queues+0x114/0x358
[  473.756217]  hrtimer_interrupt+0x104/0x2d8
[  473.756222]  arch_timer_handler_virt+0x38/0x58
[  473.756226]  handle_percpu_devid_irq+0x90/0x248
[  473.756231]  generic_handle_irq+0x34/0x50
[  473.756234]  __handle_domain_irq+0x68/0xc0
[  473.756236]  gic_handle_irq+0x6c/0x150
[  473.756238]  el1_irq+0xb8/0x140
[  473.756286]  ext4_es_lookup_extent+0xdc/0x258 [ext4]
[  473.756310]  ext4_map_blocks+0x64/0x5c0 [ext4]
[  473.756333]  ext4_getblk+0x6c/0x1d0 [ext4]
[  473.756356]  ext4_bread_batch+0x7c/0x1f8 [ext4]
[  473.756379]  ext4_find_entry+0x124/0x3f8 [ext4]
[  473.756402]  ext4_lookup+0x8c/0x258 [ext4]
[  473.756407]  __lookup_hash+0x8c/0xe8
[  473.756411]  filename_create+0xa0/0x170
[  473.756413]  do_mkdirat+0x6c/0x140
[  473.756415]  __arm64_sys_mkdirat+0x28/0x38
[  473.756419]  el0_svc_common+0x78/0x130
[  473.756421]  el0_svc_handler+0x38/0x78
[  473.756423]  el0_svc+0x8/0xc
[  485.755156] watchdog: BUG: soft lockup - CPU#2 stuck for 22s! [tmp:5149]

Add cond_resched() to avoid soft lockup and to provide a better
system responding.

Link: https://lore.kernel.org/r/20200215080206.13293-1-luoshijie1@huawei.com
Signed-off-by: Shijie Luo <luoshijie1@huawei.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:22 +01:00
Qian Cai
1673674ccd ext4: fix a data race in EXT4_I(inode)->i_disksize
commit 35df4299a6 upstream.

EXT4_I(inode)->i_disksize could be accessed concurrently as noticed by
KCSAN,

 BUG: KCSAN: data-race in ext4_write_end [ext4] / ext4_writepages [ext4]

 write to 0xffff91c6713b00f8 of 8 bytes by task 49268 on cpu 127:
  ext4_write_end+0x4e3/0x750 [ext4]
  ext4_update_i_disksize at fs/ext4/ext4.h:3032
  (inlined by) ext4_update_inode_size at fs/ext4/ext4.h:3046
  (inlined by) ext4_write_end at fs/ext4/inode.c:1287
  generic_perform_write+0x208/0x2a0
  ext4_buffered_write_iter+0x11f/0x210 [ext4]
  ext4_file_write_iter+0xce/0x9e0 [ext4]
  new_sync_write+0x29c/0x3b0
  __vfs_write+0x92/0xa0
  vfs_write+0x103/0x260
  ksys_write+0x9d/0x130
  __x64_sys_write+0x4c/0x60
  do_syscall_64+0x91/0xb47
  entry_SYSCALL_64_after_hwframe+0x49/0xbe

 read to 0xffff91c6713b00f8 of 8 bytes by task 24872 on cpu 37:
  ext4_writepages+0x10ac/0x1d00 [ext4]
  mpage_map_and_submit_extent at fs/ext4/inode.c:2468
  (inlined by) ext4_writepages at fs/ext4/inode.c:2772
  do_writepages+0x5e/0x130
  __writeback_single_inode+0xeb/0xb20
  writeback_sb_inodes+0x429/0x900
  __writeback_inodes_wb+0xc4/0x150
  wb_writeback+0x4bd/0x870
  wb_workfn+0x6b4/0x960
  process_one_work+0x54c/0xbe0
  worker_thread+0x80/0x650
  kthread+0x1e0/0x200
  ret_from_fork+0x27/0x50

 Reported by Kernel Concurrency Sanitizer on:
 CPU: 37 PID: 24872 Comm: kworker/u261:2 Tainted: G        W  O L 5.5.0-next-20200204+ #5
 Hardware name: HPE ProLiant DL385 Gen10/ProLiant DL385 Gen10, BIOS A40 07/10/2019
 Workqueue: writeback wb_workfn (flush-7:0)

Since only the read is operating as lockless (outside of the
"i_data_sem"), load tearing could introduce a logic bug. Fix it by
adding READ_ONCE() for the read and WRITE_ONCE() for the write.

Signed-off-by: Qian Cai <cai@lca.pw>
Link: https://lore.kernel.org/r/1581085751-31793-1-git-send-email-cai@lca.pw
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:22 +01:00
Miaohe Lin
56b3949a2b KVM: x86: don't notify userspace IOAPIC on edge-triggered interrupt EOI
commit 7455a83276 upstream.

Commit 13db77347d ("KVM: x86: don't notify userspace IOAPIC on edge
EOI") said, edge-triggered interrupts don't set a bit in TMR, which means
that IOAPIC isn't notified on EOI. And var level indicates level-triggered
interrupt.
But commit 3159d36ad7 ("KVM: x86: use generic function for MSI parsing")
replace var level with irq.level by mistake. Fix it by changing irq.level
to irq.trig_mode.

Cc: stable@vger.kernel.org
Fixes: 3159d36ad7 ("KVM: x86: use generic function for MSI parsing")
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:22 +01:00
Paolo Bonzini
24dfae91a2 KVM: nVMX: Don't emulate instructions in guest mode
commit 07721feee4 upstream.

vmx_check_intercept is not yet fully implemented. To avoid emulating
instructions disallowed by the L1 hypervisor, refuse to emulate
instructions by default.

Cc: stable@vger.kernel.org
[Made commit, added commit msg - Oliver]
Signed-off-by: Oliver Upton <oupton@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:22 +01:00
Suren Baghdasaryan
e61c236dcf sched/psi: Fix OOB write when writing 0 bytes to PSI files
commit 6fcca0fa48 upstream.

Issuing write() with count parameter set to 0 on any file under
/proc/pressure/ will cause an OOB write because of the access to
buf[buf_size-1] when NUL-termination is performed. Fix this by checking
for buf_size to be non-zero.

Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Link: https://lkml.kernel.org/r/20200203212216.7076-1-surenb@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:21 +01:00
Jani Nikula
26ae0493c1 drm/i915: Update drm/i915 bug filing URL
commit 7ddc7005a0 upstream.

We've moved from bugzilla to gitlab.

Cc: stable@vger.kernel.org
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200212160434.6437-2-jani.nikula@intel.com
(cherry picked from commit ddae4d7af0)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:21 +01:00
Chris Wilson
2104c4905a drm/i915: Wean off drm_pci_alloc/drm_pci_free
commit aa3146193a upstream.

drm_pci_alloc and drm_pci_free are just very thin wrappers around
dma_alloc_coherent, with a note that we should be removing them.
Furthermore since

commit de09d31dd3
Author: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Date:   Fri Jan 15 16:51:42 2016 -0800

    page-flags: define PG_reserved behavior on compound pages

    As far as I can see there's no users of PG_reserved on compound pages.
    Let's use PF_NO_COMPOUND here.

drm_pci_alloc has been declared broken since it mixes GFP_COMP and
SetPageReserved. Avoid this conflict by weaning ourselves off using the
abstraction and using the dma functions directly.

Reported-by: Taketo Kabe
Closes: https://gitlab.freedesktop.org/drm/intel/issues/1027
Fixes: de09d31dd3 ("page-flags: define PG_reserved behavior on compound pages")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: <stable@vger.kernel.org> # v4.5+
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20200202153934.3899472-1-chris@chris-wilson.co.uk
(cherry picked from commit c6790dc223)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:21 +01:00
Lyude Paul
3e740fa80c drm/nouveau/kms/gv100-: Re-set LUT after clearing for modesets
commit f287d3d197 upstream.

While certain modeset operations on gv100+ need us to temporarily
disable the LUT, we make the mistake of sometimes neglecting to
reprogram the LUT after such modesets. In particular, moving a head from
one encoder to another seems to trigger this quite often. GV100+ is very
picky about having a LUT in most scenarios, so this causes the display
engine to hang with the following error code:

disp: chid 1 stat 00005080 reason 5 [INVALID_STATE] mthd 0200 data
00000001 code 0000002d)

So, fix this by always re-programming the LUT if we're clearing it in a
state where the wndw is still visible, and has a XLUT handle programmed.

Signed-off-by: Lyude Paul <lyude@redhat.com>
Fixes: facaed62b4 ("drm/nouveau/kms/gv100: initial support")
Cc: <stable@vger.kernel.org> # v4.18+
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:21 +01:00
Alex Deucher
5e7dda6dda drm/amdgpu/gfx10: disable gfxoff when reading rlc clock
commit b08c3ed609 upstream.

Otherwise we readback all ones.  Fixes rlc counter
readback while gfxoff is active.

Reviewed-by: Xiaojie Yuan <xiaojie.yuan@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:21 +01:00
Alex Deucher
7e482baf6d drm/amdgpu/gfx9: disable gfxoff when reading rlc clock
commit 120cf95930 upstream.

Otherwise we readback all ones.  Fixes rlc counter
readback while gfxoff is active.

Reviewed-by: Xiaojie Yuan <xiaojie.yuan@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:21 +01:00
Alex Deucher
f141fac489 drm/amdgpu/soc15: fix xclk for raven
commit c657b936ea upstream.

It's 25 Mhz (refclk / 4).  This fixes the interpretation
of the rlc clock counter.

Acked-by: Evan Quan <evan.quan@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:21 +01:00
Catalin Marinas
95236ae76b mm: Avoid creating virtual address aliases in brk()/mmap()/mremap()
commit dcde237319 upstream.

Currently the arm64 kernel ignores the top address byte passed to brk(),
mmap() and mremap(). When the user is not aware of the 56-bit address
limit or relies on the kernel to return an error, untagging such
pointers has the potential to create address aliases in user-space.
Passing a tagged address to munmap(), madvise() is permitted since the
tagged pointer is expected to be inside an existing mapping.

The current behaviour breaks the existing glibc malloc() implementation
which relies on brk() with an address beyond 56-bit to be rejected by
the kernel.

Remove untagging in the above functions by partially reverting commit
ce18d171cb ("mm: untag user pointers in mmap/munmap/mremap/brk"). In
addition, update the arm64 tagged-address-abi.rst document accordingly.

Link: https://bugzilla.redhat.com/1797052
Fixes: ce18d171cb ("mm: untag user pointers in mmap/munmap/mremap/brk")
Cc: <stable@vger.kernel.org> # 5.4.x-
Cc: Florian Weimer <fweimer@redhat.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Reported-by: Victor Stinner <vstinner@redhat.com>
Acked-by: Will Deacon <will@kernel.org>
Acked-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:21 +01:00
Alexander Potapenko
9bb971b335 lib/stackdepot.c: fix global out-of-bounds in stack_slabs
commit 305e519ce4 upstream.

Walter Wu has reported a potential case in which init_stack_slab() is
called after stack_slabs[STACK_ALLOC_MAX_SLABS - 1] has already been
initialized.  In that case init_stack_slab() will overwrite
stack_slabs[STACK_ALLOC_MAX_SLABS], which may result in a memory
corruption.

Link: http://lkml.kernel.org/r/20200218102950.260263-1-glider@google.com
Fixes: cd11016e5f ("mm, kasan: stackdepot implementation. Enable stackdepot for SLAB")
Signed-off-by: Alexander Potapenko <glider@google.com>
Reported-by: Walter Wu <walter-zh.wu@mediatek.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:20 +01:00
Wei Yang
ef32399bf7 mm/sparsemem: pfn_to_page is not valid yet on SPARSEMEM
commit 18e19f195c upstream.

When we use SPARSEMEM instead of SPARSEMEM_VMEMMAP, pfn_to_page()
doesn't work before sparse_init_one_section() is called.

This leads to a crash when hotplug memory:

    BUG: unable to handle page fault for address: 0000000006400000
    #PF: supervisor write access in kernel mode
    #PF: error_code(0x0002) - not-present page
    PGD 0 P4D 0
    Oops: 0002 [#1] SMP PTI
    CPU: 3 PID: 221 Comm: kworker/u16:1 Tainted: G        W         5.5.0-next-20200205+ #343
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 0.0.0 02/06/2015
    Workqueue: kacpi_hotplug acpi_hotplug_work_fn
    RIP: 0010:__memset+0x24/0x30
    Code: cc cc cc cc cc cc 0f 1f 44 00 00 49 89 f9 48 89 d1 83 e2 07 48 c1 e9 03 40 0f b6 f6 48 b8 01 01 01 01 01 01 01 01 48 0f af c6 <f3> 48 ab 89 d1 f3 aa 4c 89 c8 c3 90 49 89 f9 40 88 f0 48 89 d1 f3
    RSP: 0018:ffffb43ac0373c80 EFLAGS: 00010a87
    RAX: ffffffffffffffff RBX: ffff8a1518800000 RCX: 0000000000050000
    RDX: 0000000000000000 RSI: 00000000000000ff RDI: 0000000006400000
    RBP: 0000000000140000 R08: 0000000000100000 R09: 0000000006400000
    R10: 0000000000000000 R11: 0000000000000002 R12: 0000000000000000
    R13: 0000000000000028 R14: 0000000000000000 R15: ffff8a153ffd9280
    FS:  0000000000000000(0000) GS:ffff8a153ab00000(0000) knlGS:0000000000000000
    CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
    CR2: 0000000006400000 CR3: 0000000136fca000 CR4: 00000000000006e0
    DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
    DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
    Call Trace:
     sparse_add_section+0x1c9/0x26a
     __add_pages+0xbf/0x150
     add_pages+0x12/0x60
     add_memory_resource+0xc8/0x210
     __add_memory+0x62/0xb0
     acpi_memory_device_add+0x13f/0x300
     acpi_bus_attach+0xf6/0x200
     acpi_bus_scan+0x43/0x90
     acpi_device_hotplug+0x275/0x3d0
     acpi_hotplug_work_fn+0x1a/0x30
     process_one_work+0x1a7/0x370
     worker_thread+0x30/0x380
     kthread+0x112/0x130
     ret_from_fork+0x35/0x40

We should use memmap as it did.

On x86 the impact is limited to x86_32 builds, or x86_64 configurations
that override the default setting for SPARSEMEM_VMEMMAP.

Other memory hotplug archs (arm64, ia64, and ppc) also default to
SPARSEMEM_VMEMMAP=y.

[dan.j.williams@intel.com: changelog update]
{rppt@linux.ibm.com: changelog update]
Link: http://lkml.kernel.org/r/20200219030454.4844-1-bhe@redhat.com
Fixes: ba72b4c8cf ("mm/sparsemem: support sub-section hotplug")
Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Signed-off-by: Baoquan He <bhe@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Baoquan He <bhe@redhat.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:20 +01:00
Gavin Shan
198f5aa0f7 mm/vmscan.c: don't round up scan size for online memory cgroup
commit 76073c646f upstream.

Commit 68600f623d ("mm: don't miss the last page because of round-off
error") makes the scan size round up to @denominator regardless of the
memory cgroup's state, online or offline.  This affects the overall
reclaiming behavior: the corresponding LRU list is eligible for
reclaiming only when its size logically right shifted by @sc->priority
is bigger than zero in the former formula.

For example, the inactive anonymous LRU list should have at least 0x4000
pages to be eligible for reclaiming when we have 60/12 for
swappiness/priority and without taking scan/rotation ratio into account.

After the roundup is applied, the inactive anonymous LRU list becomes
eligible for reclaiming when its size is bigger than or equal to 0x1000
in the same condition.

    (0x4000 >> 12) * 60 / (60 + 140 + 1) = 1
    ((0x1000 >> 12) * 60) + 200) / (60 + 140 + 1) = 1

aarch64 has 512MB huge page size when the base page size is 64KB.  The
memory cgroup that has a huge page is always eligible for reclaiming in
that case.

The reclaiming is likely to stop after the huge page is reclaimed,
meaing the further iteration on @sc->priority and the silbing and child
memory cgroups will be skipped.  The overall behaviour has been changed.
This fixes the issue by applying the roundup to offlined memory cgroups
only, to give more preference to reclaim memory from offlined memory
cgroup.  It sounds reasonable as those memory is unlikedly to be used by
anyone.

The issue was found by starting up 8 VMs on a Ampere Mustang machine,
which has 8 CPUs and 16 GB memory.  Each VM is given with 2 vCPUs and
2GB memory.  It took 264 seconds for all VMs to be completely up and
784MB swap is consumed after that.  With this patch applied, it took 236
seconds and 60MB swap to do same thing.  So there is 10% performance
improvement for my case.  Note that KSM is disable while THP is enabled
in the testing.

         total     used    free   shared  buff/cache   available
   Mem:  16196    10065    2049       16        4081        3749
   Swap:  8175      784    7391
         total     used    free   shared  buff/cache   available
   Mem:  16196    11324    3656       24        1215        2936
   Swap:  8175       60    8115

Link: http://lkml.kernel.org/r/20200211024514.8730-1-gshan@redhat.com
Fixes: 68600f623d ("mm: don't miss the last page because of round-off error")
Signed-off-by: Gavin Shan <gshan@redhat.com>
Acked-by: Roman Gushchin <guro@fb.com>
Cc: <stable@vger.kernel.org>	[4.20+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:20 +01:00
Zenghui Yu
8735a5b6e1 genirq/irqdomain: Make sure all irq domain flags are distinct
commit 2546287c5f upstream.

This was noticed when printing debugfs for MSIs on my ARM64 server.  The
new dstate IRQD_MSI_NOMASK_QUIRK came out surprisingly while it should only
be the x86 stuff for the time being...

The new MSI quirk flag uses the same bit as IRQ_DOMAIN_NAME_ALLOCATED which
is oddly defined as bit 6 for no good reason.

Switch it to the non used bit 1.

Fixes: 6f1a4891a5 ("x86/apic/msi: Plug non-maskable MSI affinity race")
Signed-off-by: Zenghui Yu <yuzenghui@huawei.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20200221020725.2038-1-yuzenghui@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:20 +01:00
Logan Gunthorpe
6e304262e3 nvme-multipath: Fix memory leak with ana_log_buf
commit 3b7830904e upstream.

kmemleak reports a memory leak with the ana_log_buf allocated by
nvme_mpath_init():

unreferenced object 0xffff888120e94000 (size 8208):
  comm "nvme", pid 6884, jiffies 4295020435 (age 78786.312s)
    hex dump (first 32 bytes):
      00 00 00 00 00 00 00 00 01 00 00 00 00 00 00 00  ................
      01 00 00 00 01 00 00 00 00 00 00 00 00 00 00 00  ................
    backtrace:
      [<00000000e2360188>] kmalloc_order+0x97/0xc0
      [<0000000079b18dd4>] kmalloc_order_trace+0x24/0x100
      [<00000000f50c0406>] __kmalloc+0x24c/0x2d0
      [<00000000f31a10b9>] nvme_mpath_init+0x23c/0x2b0
      [<000000005802589e>] nvme_init_identify+0x75f/0x1600
      [<0000000058ef911b>] nvme_loop_configure_admin_queue+0x26d/0x280
      [<00000000673774b9>] nvme_loop_create_ctrl+0x2a7/0x710
      [<00000000f1c7a233>] nvmf_dev_write+0xc66/0x10b9
      [<000000004199f8d0>] __vfs_write+0x50/0xa0
      [<0000000065466fef>] vfs_write+0xf3/0x280
      [<00000000b0db9a8b>] ksys_write+0xc6/0x160
      [<0000000082156b91>] __x64_sys_write+0x43/0x50
      [<00000000c34fbb6d>] do_syscall_64+0x77/0x2f0
      [<00000000bbc574c9>] entry_SYSCALL_64_after_hwframe+0x49/0xbe

nvme_mpath_init() is called by nvme_init_identify() which is called in
multiple places (nvme_reset_work(), nvme_passthru_end(), etc). This
means nvme_mpath_init() may be called multiple times before
nvme_mpath_uninit() (which is only called on nvme_free_ctrl()).

When nvme_mpath_init() is called multiple times, it overwrites the
ana_log_buf pointer with a new allocation, thus leaking the previous
allocation.

To fix this, free ana_log_buf before allocating a new one.

Fixes: 0d0b660f21 ("nvme: add ANA support")
Cc: <stable@vger.kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:20 +01:00
Vasily Averin
e078c8d897 mm/memcontrol.c: lost css_put in memcg_expand_shrinker_maps()
commit 75866af62b upstream.

for_each_mem_cgroup() increases css reference counter for memory cgroup
and requires to use mem_cgroup_iter_break() if the walk is cancelled.

Link: http://lkml.kernel.org/r/c98414fb-7e1f-da0f-867a-9340ec4bd30b@virtuozzo.com
Fixes: 0a4465d340 ("mm, memcg: assign memcg-aware shrinkers bitmap to memcg")
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Acked-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Roman Gushchin <guro@fb.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:20 +01:00
Ioanna Alifieraki
aa4f749f81 Revert "ipc,sem: remove uneeded sem_undo_list lock usage in exit_sem()"
commit edf28f4061 upstream.

This reverts commit a979558448.

Commit a979558448 ("ipc,sem: remove uneeded sem_undo_list lock usage
in exit_sem()") removes a lock that is needed.  This leads to a process
looping infinitely in exit_sem() and can also lead to a crash.  There is
a reproducer available in [1] and with the commit reverted the issue
does not reproduce anymore.

Using the reproducer found in [1] is fairly easy to reach a point where
one of the child processes is looping infinitely in exit_sem between
for(;;) and if (semid == -1) block, while it's trying to free its last
sem_undo structure which has already been freed by freeary().

Each sem_undo struct is on two lists: one per semaphore set (list_id)
and one per process (list_proc).  The list_id list tracks undos by
semaphore set, and the list_proc by process.

Undo structures are removed either by freeary() or by exit_sem().  The
freeary function is invoked when the user invokes a syscall to remove a
semaphore set.  During this operation freeary() traverses the list_id
associated with the semaphore set and removes the undo structures from
both the list_id and list_proc lists.

For this case, exit_sem() is called at process exit.  Each process
contains a struct sem_undo_list (referred to as "ulp") which contains
the head for the list_proc list.  When the process exits, exit_sem()
traverses this list to remove each sem_undo struct.  As in freeary(),
whenever a sem_undo struct is removed from list_proc, it is also removed
from the list_id list.

Removing elements from list_id is safe for both exit_sem() and freeary()
due to sem_lock().  Removing elements from list_proc is not safe;
freeary() locks &un->ulp->lock when it performs
list_del_rcu(&un->list_proc) but exit_sem() does not (locking was
removed by commit a979558448 ("ipc,sem: remove uneeded sem_undo_list
lock usage in exit_sem()").

This can result in the following situation while executing the
reproducer [1] : Consider a child process in exit_sem() and the parent
in freeary() (because of semctl(sid[i], NSEM, IPC_RMID)).

 - The list_proc for the child contains the last two undo structs A and
   B (the rest have been removed either by exit_sem() or freeary()).

 - The semid for A is 1 and semid for B is 2.

 - exit_sem() removes A and at the same time freeary() removes B.

 - Since A and B have different semid sem_lock() will acquire different
   locks for each process and both can proceed.

The bug is that they remove A and B from the same list_proc at the same
time because only freeary() acquires the ulp lock. When exit_sem()
removes A it makes ulp->list_proc.next to point at B and at the same
time freeary() removes B setting B->semid=-1.

At the next iteration of for(;;) loop exit_sem() will try to remove B.

The only way to break from for(;;) is for (&un->list_proc ==
&ulp->list_proc) to be true which is not. Then exit_sem() will check if
B->semid=-1 which is and will continue looping in for(;;) until the
memory for B is reallocated and the value at B->semid is changed.

At that point, exit_sem() will crash attempting to unlink B from the
lists (this can be easily triggered by running the reproducer [1] a
second time).

To prove this scenario instrumentation was added to keep information
about each sem_undo (un) struct that is removed per process and per
semaphore set (sma).

          CPU0                                CPU1
  [caller holds sem_lock(sma for A)]      ...
  freeary()                               exit_sem()
  ...                                     ...
  ...                                     sem_lock(sma for B)
  spin_lock(A->ulp->lock)                 ...
  list_del_rcu(un_A->list_proc)           list_del_rcu(un_B->list_proc)

Undo structures A and B have different semid and sem_lock() operations
proceed.  However they belong to the same list_proc list and they are
removed at the same time.  This results into ulp->list_proc.next
pointing to the address of B which is already removed.

After reverting commit a979558448 ("ipc,sem: remove uneeded
sem_undo_list lock usage in exit_sem()") the issue was no longer
reproducible.

[1] https://bugzilla.redhat.com/show_bug.cgi?id=1694779

Link: http://lkml.kernel.org/r/20191211191318.11860-1-ioanna-maria.alifieraki@canonical.com
Fixes: a979558448 ("ipc,sem: remove uneeded sem_undo_list lock usage in exit_sem()")
Signed-off-by: Ioanna Alifieraki <ioanna-maria.alifieraki@canonical.com>
Acked-by: Manfred Spraul <manfred@colorfullife.com>
Acked-by: Herton R. Krzesinski <herton@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: <malat@debian.org>
Cc: Joel Fernandes (Google) <joel@joelfernandes.org>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Jay Vosburgh <jay.vosburgh@canonical.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:20 +01:00
Rafael J. Wysocki
7b77e5a082 ACPI: PM: s2idle: Check fixed wakeup events in acpi_s2idle_wake()
commit 63fb962342 upstream.

Commit fdde0ff859 ("ACPI: PM: s2idle: Prevent spurious SCIs from
waking up the system") overlooked the fact that fixed events can wake
up the system too and broke RTC wakeup from suspend-to-idle as a
result.

Fix this issue by checking the fixed events in acpi_s2idle_wake() in
addition to checking wakeup GPEs and break out of the suspend-to-idle
loop if the status bits of any enabled fixed events are set then.

Fixes: fdde0ff859 ("ACPI: PM: s2idle: Prevent spurious SCIs from waking up the system")
Reported-and-tested-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: 5.4+ <stable@vger.kernel.org> # 5.4+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:20 +01:00
Jani Nikula
f18121a59b MAINTAINERS: Update drm/i915 bug filing URL
commit 96228b7df3 upstream.

We've moved from bugzilla to gitlab.

Cc: stable@vger.kernel.org
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200212160434.6437-1-jani.nikula@intel.com
(cherry picked from commit 3a6a4f0810)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:19 +01:00
Johan Hovold
cf3c30a711 serdev: ttyport: restore client ops on deregistration
commit 0c5aae5927 upstream.

The serdev tty-port controller driver should reset the tty-port client
operations also on deregistration to avoid a NULL-pointer dereference in
case the port is later re-registered as a normal tty device.

Note that this can only happen with tty drivers such as 8250 which have
statically allocated port structures that can end up being reused and
where a later registration would not register a serdev controller (e.g.
due to registration errors or if the devicetree has been changed in
between).

Specifically, this can be an issue for any statically defined ports that
would be registered by 8250 core when an 8250 driver is being unbound.

Fixes: bed35c6dfa ("serdev: add a tty port controller driver")
Cc: stable <stable@vger.kernel.org>     # 4.11
Reported-by: Loic Poulain <loic.poulain@linaro.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20200210145730.22762-1-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:19 +01:00
satya priya
80990c30b7 tty: serial: qcom_geni_serial: Fix RX cancel command failure
commit 679aac5ead upstream.

RX cancel command fails when BT is switched on and off multiple times.

To handle this, poll for the cancel bit in SE_GENI_S_IRQ_STATUS register
instead of SE_GENI_S_CMD_CTRL_REG.

As per the HPG update, handle the RX last bit after cancel command
and flush out the RX FIFO buffer.

Signed-off-by: satya priya <skakit@codeaurora.org>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/1581415982-8793-1-git-send-email-skakit@codeaurora.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 17:22:19 +01:00