linux-stable.git/include/linux, branch linux-4.10.y

dax: prevent invalidation of mapped DAX entries

2017-05-20T12:31:02+00:00

commit 4636e70bb0a8b871998b6841a2e4b205cf2bc863 upstream.

Patch series "mm,dax: Fix data corruption due to mmap inconsistency",
v4.

This series fixes data corruption that can happen for DAX mounts when
page faults race with write(2) and as a result page tables get out of
sync with block mappings in the filesystem and thus data seen through
mmap is different from data seen through read(2).

The series passes testing with t_mmap_stale test program from Ross and
also other mmap related tests on DAX filesystem.

This patch (of 4):

dax_invalidate_mapping_entry() currently removes DAX exceptional entries
only if they are clean and unlocked.  This is done via:

  invalidate_mapping_pages()
    invalidate_exceptional_entry()
      dax_invalidate_mapping_entry()

However, for page cache pages removed in invalidate_mapping_pages()
there is an additional criteria which is that the page must not be
mapped.  This is noted in the comments above invalidate_mapping_pages()
and is checked in invalidate_inode_page().

For DAX entries this means that we can can end up in a situation where a
DAX exceptional entry, either a huge zero page or a regular DAX entry,
could end up mapped but without an associated radix tree entry.  This is
inconsistent with the rest of the DAX code and with what happens in the
page cache case.

We aren't able to unmap the DAX exceptional entry because according to
its comments invalidate_mapping_pages() isn't allowed to block, and
unmap_mapping_range() takes a write lock on the mapping->i_mmap_rwsem.

Since we essentially never have unmapped DAX entries to evict from the
radix tree, just remove dax_invalidate_mapping_entry().

Fixes: c6dcf52c23d2 ("mm: Invalidate DAX radix tree entries only if appropriate")
Link: http://lkml.kernel.org/r/20170510085419.27601-2-jack@suse.cz
Signed-off-by: Ross Zwisler 
Signed-off-by: Jan Kara 
Reported-by: Jan Kara 
Cc: Dan Williams 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

block: get rid of blk_integrity_revalidate()

2017-05-14T12:08:30+00:00

commit 19b7ccf8651df09d274671b53039c672a52ad84d upstream.

Commit 25520d55cdb6 ("block: Inline blk_integrity in struct gendisk")
introduced blk_integrity_revalidate(), which seems to assume ownership
of the stable pages flag and unilaterally clears it if no blk_integrity
profile is registered:

    if (bi->profile)
            disk->queue->backing_dev_info->capabilities |=
                    BDI_CAP_STABLE_WRITES;
    else
            disk->queue->backing_dev_info->capabilities &=
                    ~BDI_CAP_STABLE_WRITES;

It's called from revalidate_disk() and rescan_partitions(), making it
impossible to enable stable pages for drivers that support partitions
and don't use blk_integrity: while the call in revalidate_disk() can be
trivially worked around (see zram, which doesn't support partitions and
hence gets away with zram_revalidate_disk()), rescan_partitions() can
be triggered from userspace at any time.  This breaks rbd, where the
ceph messenger is responsible for generating/verifying CRCs.

Since blk_integrity_{un,}register() "must" be used for (un)registering
the integrity profile with the block layer, move BDI_CAP_STABLE_WRITES
setting there.  This way drivers that call blk_integrity_register() and
use integrity infrastructure won't interfere with drivers that don't
but still want stable pages.

Fixes: 25520d55cdb6 ("block: Inline blk_integrity in struct gendisk")
Cc: "Martin K. Petersen" 
Cc: Christoph Hellwig 
Cc: Mike Snitzer 
Tested-by: Dan Williams 
Signed-off-by: Ilya Dryomov 
[idryomov@gmail.com: backport to < 4.11: bdi is embedded in queue]
Signed-off-by: Jens Axboe 
Signed-off-by: Greg Kroah-Hartman

f2fs: sanity check segment count

2017-05-14T12:08:30+00:00

commit b9dd46188edc2f0d1f37328637860bb65a771124 upstream.

F2FS uses 4 bytes to represent block address. As a result, supported
size of disk is 16 TB and it equals to 16 * 1024 * 1024 / 2 segments.

Signed-off-by: Jin Qian 
Signed-off-by: Jaegeuk Kim 
Signed-off-by: Greg Kroah-Hartman

usb: chipidea: Handle extcon events properly

2017-05-14T12:08:25+00:00

commit a89b94b53371bbfa582787c2fa3378000ea4263d upstream.

We're currently emulating the vbus and id interrupts in the OTGSC
read API, but we also need to make sure that if we're handling
the events with extcon that we don't enable the interrupts for
those events in the hardware. Therefore, properly emulate this
register if we're using extcon, but don't enable the interrupts.
This allows me to get my cable connect/disconnect working
properly without getting spurious interrupts on my device that
uses an extcon for these two events.

Acked-by: Peter Chen 
Cc: Greg Kroah-Hartman 
Cc: "Ivan T. Ivanov" 
Fixes: 3ecb3e09b042 ("usb: chipidea: Use extcon framework for VBUS and ID detect")
Signed-off-by: Stephen Boyd 
Signed-off-by: Peter Chen 
Signed-off-by: Greg Kroah-Hartman

net: phy: fix auto-negotiation stall due to unavailable interrupt

2017-05-03T15:37:42+00:00

[ Upstream commit f555f34fdc586a56204cd16d9a7c104ec6cb6650 ]

The Ethernet link on an interrupt driven PHY was not coming up if the Ethernet
cable was plugged before the Ethernet interface was brought up.

The patch trigger PHY state machine to update link state if PHY was requested to
do auto-negotiation and auto-negotiation complete flag already set.

During power-up cycle the PHY do auto-negotiation, generate interrupt and set
auto-negotiation complete flag. Interrupt is handled by PHY state machine but
doesn't update link state because PHY is in PHY_READY state. After some time
MAC bring up, start and request PHY to do auto-negotiation. If there are no new
settings to advertise genphy_config_aneg() doesn't start PHY auto-negotiation.
PHY continue to stay in auto-negotiation complete state and doesn't fire
interrupt. At the same time PHY state machine expect that PHY started
auto-negotiation and is waiting for interrupt from PHY and it won't get it.

Fixes: 321beec5047a ("net: phy: Use interrupts when available in NOLINK state")
Signed-off-by: Alexander Kochetkov 
Cc: stable  # v4.9+
Tested-by: Roger Quadros 
Tested-by: Alexandre Belloni 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

tcp: mark skbs with SCM_TIMESTAMPING_OPT_STATS

2017-05-03T15:37:41+00:00

[ Upstream commit 4ef1b2869447411ad3ef91ad7d4891a83c1a509a ]

SOF_TIMESTAMPING_OPT_STATS can be enabled and disabled
while packets are collected on the error queue.
So, checking SOF_TIMESTAMPING_OPT_STATS in sk->sk_tsflags
is not enough to safely assume that the skb contains
OPT_STATS data.

Add a bit in sock_exterr_skb to indicate whether the
skb contains opt_stats data.

Fixes: 1c885808e456 ("tcp: SOF_TIMESTAMPING_OPT_STATS option for SO_TIMESTAMPING")
Reported-by: JongHwan Kim 
Signed-off-by: Soheil Hassas Yeganeh 
Signed-off-by: Eric Dumazet 
Signed-off-by: Willem de Bruijn 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

new privimitive: iov_iter_revert()

2017-04-21T07:32:40+00:00

commit 27c0e3748e41ca79171ffa3e97415a20af6facd0 upstream.

opposite to iov_iter_advance(); the caller is responsible for never
using it to move back past the initial position.

Signed-off-by: Al Viro 
Signed-off-by: Greg Kroah-Hartman

cgroup, kthread: close race window where new kthreads can be migrated to non-root cgroups

2017-04-21T07:32:36+00:00

commit 77f88796cee819b9c4562b0b6b44691b3b7755b1 upstream.

Creation of a kthread goes through a couple interlocked stages between
the kthread itself and its creator.  Once the new kthread starts
running, it initializes itself and wakes up the creator.  The creator
then can further configure the kthread and then let it start doing its
job by waking it up.

In this configuration-by-creator stage, the creator is the only one
that can wake it up but the kthread is visible to userland.  When
altering the kthread's attributes from userland is allowed, this is
fine; however, for cases where CPU affinity is critical,
kthread_bind() is used to first disable affinity changes from userland
and then set the affinity.  This also prevents the kthread from being
migrated into non-root cgroups as that can affect the CPU affinity and
many other things.

Unfortunately, the cgroup side of protection is racy.  While the
PF_NO_SETAFFINITY flag prevents further migrations, userland can win
the race before the creator sets the flag with kthread_bind() and put
the kthread in a non-root cgroup, which can lead to all sorts of
problems including incorrect CPU affinity and starvation.

This bug got triggered by userland which periodically tries to migrate
all processes in the root cpuset cgroup to a non-root one.  Per-cpu
workqueue workers got caught while being created and ended up with
incorrected CPU affinity breaking concurrency management and sometimes
stalling workqueue execution.

This patch adds task->no_cgroup_migration which disallows the task to
be migrated by userland.  kthreadd starts with the flag set making
every child kthread start in the root cgroup with migration
disallowed.  The flag is cleared after the kthread finishes
initialization by which time PF_NO_SETAFFINITY is set if the kthread
should stay in the root cgroup.

It'd be better to wait for the initialization instead of failing but I
couldn't think of a way of implementing that without adding either a
new PF flag, or sleeping and retrying from waiting side.  Even if
userland depends on changing cgroup membership of a kthread, it either
has to be synchronized with kthread_create() or periodically repeat,
so it's unlikely that this would break anything.

v2: Switch to a simpler implementation using a new task_struct bit
    field suggested by Oleg.

Signed-off-by: Tejun Heo 
Suggested-by: Oleg Nesterov 
Cc: Linus Torvalds 
Cc: Andrew Morton 
Cc: Peter Zijlstra (Intel) 
Cc: Thomas Gleixner 
Reported-and-debugged-by: Chris Mason 
Signed-off-by: Tejun Heo 
Signed-off-by: Greg Kroah-Hartman

PCI: Disable MSI for HiSilicon Hip06/Hip07 Root Ports

2017-04-12T10:42:12+00:00

[ Upstream commit 72f2ff0deb870145a5a2d24cd75b4f9936159a62 ]

The PCIe Root Port in Hip06/Hip07 SoCs advertises an MSI capability, but it
cannot generate MSIs.  It can transfer MSI/MSI-X from downstream devices,
but does not support MSI/MSI-X itself.

Add a quirk to prevent use of MSI/MSI-X by the Root Port.

[bhelgaas: changelog, sort vendor ID #define, drop device ID #define]
Signed-off-by: Dongdong Liu 
Signed-off-by: Bjorn Helgaas 
Reviewed-by: Gabriele Paoloni 
Reviewed-by: Zhou Wang 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

ARM: smccc: Update HVC comment to describe new quirk parameter

2017-04-12T10:42:12+00:00

[ Upstream commit 3046ec674d441562c6bb3e4284cd866743042ef3 ]

Commit 680a0873e193 ("arm: kernel: Add SMC structure parameter") added
a new "quirk" parameter to the SMC and HVC SMCCC backends, but only
updated the comment for the SMC version. This patch adds the new
paramater to the comment describing the HVC version too.

Signed-off-by: Will Deacon 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman