Because currently we have no idea what the transaction context we
are operating in is, and I need to know that information to track
down bugs in multiple log item joins to transactions.
Signed-Off-By: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>

The log item flags contain a field that is protected by the AIL
lock - the XFS_LI_IN_AIL flag. We use non-atomic RMW operations to
set and clear these flags, but most of the updates and checks are
not done with the AIL lock held and so are susceptible to update
races.

Fix this by changing the log item flags to use atomic bitops rather
than be reliant on the AIL lock for update serialisation.
Signed-Off-By: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>

xfs_rmap_lookup_le_range can return errors, so we need to check for
them and bail out.
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NBrian Foster <bfoster@redhat.com>

Don't panic() the system if the bmap records are garbage, just call
ASSERT which gives us the same backtrace but enables developers to
control if the system goes down or not.  This makes debugging with
generic/388 much easier because it won't reboot the machine midway
through a run just because btree_read_bufl returns EIO when the fs has
already shut down.
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NBrian Foster <bfoster@redhat.com>

Directory operations can perform block allocations as entries are
added/removed from directories. Defer AGFL block frees from the
remaining directory operation transactions. This covers the hard
link, remove and rename operations.
Signed-off-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>

Inode allocation can require block allocation for physical inode
chunk allocation, inode btree record insertion, and/or directory
block allocation for entry insertion. Any of these block allocation
requests can require AGFL fixups prior to the actual allocation.
Update the common file creation transacions to defer AGFL frees from
these contexts to avoid too much log reservation consumption
per-transaction.

Since these transactions are already passed down through the btree
cursors and da_args structure, this simply requires to attach dfops
to the transaction. Note that this covers tr_create, tr_mkdir and
tr_symlink. Other transactions such as tr_create_tmpfile do not
already make use of deferred operations and so are left alone for
the time being.
Signed-off-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>

XFS inode chunks are already freed via deferred operations (which
now also defer AGFL block frees), but inode btree blocks are freed
directly in the associated context. This has been known to lead to
log reservation overruns in particular workloads where an inobt
block free may require several AGFL block frees (and thus several
allocation btree modifications) before the inobt block itself is
actually freed.

To avoid this problem, defer the frees of any AGFL blocks before the
inobt block free takes place. This requires passing the dfops from
xfs_inactive_ifree() down through the inobt ->[alloc|free]_block()
callouts, which essentially only requires to attach the dfops to the
transaction since it is already carried all the way through to the
inobt update and allocation.
Signed-off-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>

Now that AGFL block frees are deferred when dfops is set in the
transaction, start deferring AGFL block frees from contexts that are
known to push the limits of existing log reservations.

The first such context is deferred operation processing itself. This
primarily targets deferred extent frees (such as file extents and
inode chunks), but in doing so covers all allocation operations that
occur in deferred operation processing context.

Update xfs_defer_finish() to set and reset ->t_agfl_dfops across the
processing sequence. This means that any AGFL block frees due to
allocation events result in the addition of new EFIs to the dfops
rather than being processed immediately. xfs_defer_finish() rolls
the transaction at least once more to process the frees of the AGFL
blocks back to the allocation btrees and returns once the AGFL is
rectified.
Signed-off-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>

The AGFL fixup code executes before every block allocation/free and
rectifies the AGFL based on the current, dynamic allocation
requirements of the fs. The AGFL must hold a minimum number of
blocks to satisfy a worst case split of the free space btrees caused
by the impending allocation operation. The AGFL is also updated to
maintain the implicit requirement for a minimum number of free slots
to satisfy a worst case join of the free space btrees.

Since the AGFL caches individual blocks, AGFL reduction typically
involves multiple, single block frees. We've had reports of
transaction overrun problems during certain workloads that boil down
to AGFL reduction freeing multiple blocks and consuming more space
in the log than was reserved for the transaction.

Since the objective of freeing AGFL blocks is to ensure free AGFL
free slots are available for the upcoming allocation, one way to
address this problem is to release surplus blocks from the AGFL
immediately but defer the free of those blocks (similar to how
file-mapped blocks are unmapped from the file in one transaction and
freed via a deferred operation) until the transaction is rolled.
This turns AGFL reduction into an operation with predictable log
reservation consumption.

Add the capability to defer AGFL block frees when a deferred ops
list is available to the AGFL fixup code. Add a dfops pointer to the
transaction to carry dfops through various contexts to the allocator
context. Deferring AGFL frees is  conditional behavior based on
whether the transaction pointer is populated. The long term
objective is to reuse the transaction pointer to clean up all
unrelated callchains that pass dfops on the stack along with a
transaction and in doing so, consistently defer AGFL blocks from the
allocator.

A bit of customization is required to handle deferred completion
processing because AGFL blocks are accounted against a per-ag
reservation pool and AGFL blocks are not inserted into the extent
busy list when freed (they are inserted when used and released back
to the AGFL). Reuse the majority of the existing deferred extent
free infrastructure and customize it appropriately to handle AGFL
blocks.

Note that this patch only adds infrastructure. It does not change
behavior because no callers have been updated to pass ->t_agfl_dfops
into the allocation code.
Signed-off-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>

Refactor the AGFL block free code into a new helper such that it can
be invoked from deferred context. No functional changes.
Signed-off-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>

Rather than printing the top of the buffer that held a corrupted dqblk,
restructure things to print out the specific one that failed by pushing
the calls to the verifier_error function down into the verifier which
iterates over the buffer and detects the error.
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>

Add an xfs_dqblk verifier so that it can check the uuid on V5 filesystems;
it calls the existing xfs_dquot_verify verifier to validate the
xfs_disk_dquot_t contained inside it.  This lets us move the uuid
verification out of the crc verifier, which makes little sense.
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>

It's a bit dicey to pass in the smaller xfs_disk_dquot and then cast it to
something larger; pass in the full xfs_dqblk so we know the caller has sent
us the right thing.  Rename the function to xfs_dqblk_repair for
clarity.
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>

During quotacheck we send in the quota type, so verify that as well.
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>

Long ago the flags argument was used to determine whether to issue warnings
about corruptions, but that's done elsewhere now and the flag is unused
here, so remove it.
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>

Rather than checking what kind of locking is needed in a helper
function and then jumping through hoops to do the locking in line,
move the locking to the helper function that does all the checks
and rename it to xfs_ilock_for_iomap().

This also allows us to hoist all the nonblocking checks up into the
locking helper, further simplifier the code flow in
xfs_file_iomap_begin() and making it easier to understand.
Signed-Off-By: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NCarlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>

The current logic that determines whether allocation should be done
has grown somewhat spaghetti like with the addition of IOMAP_NOWAIT
functionality. Separate out each of the different cases into single,
obvious checks to get rid most of the nested IOMAP_NOWAIT checks
in the allocation logic.
Signed-Off-By: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NCarlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>

If we are doing direct IO writes with datasync semantics, we often
have to flush metadata changes along with the data write. However,
if we are overwriting existing data, there are no metadata changes
that we need to flush. In this case, optimising the IO by using
FUA write makes sense.

We know from the IOMAP_F_DIRTY flag as to whether a specific inode
requires a metadata flush - this is currently used by DAX to ensure
extent modification as stable in page fault operations. For direct
IO writes, we can use it to determine if we need to flush metadata
or not once the data is on disk.

Hence if we have been returned a mapped extent that is not new and
the IO mapping is not dirty, then we can use a FUA write to provide
datasync semantics. This allows us to short-cut the
generic_write_sync() call in IO completion and hence avoid
unnecessary operations. This makes pure direct IO data write
behaviour identical to the way block devices use REQ_FUA to provide
datasync semantics.

On a FUA enabled device, a synchronous direct IO write workload
(sequential 4k overwrites in 32MB file) had the following results:

# xfs_io -fd -c "pwrite -V 1 -D 0 32m" /mnt/scratch/boo

kernel		time	write()s	write iops	Write b/w
------		----	--------	----------	---------
(no dsync)	 4s	2173/s		2173		8.5MB/s
vanilla		22s	 370/s		 750		1.4MB/s
patched		19s	 420/s		 420		1.6MB/s

The patched code clearly doesn't send cache flushes anymore, but
instead uses FUA (confirmed via blktrace), and performance improves
a bit as a result. However, the benefits will be higher on workloads
that mix O_DSYNC overwrites with other write IO as we won't be
flushing the entire device cache on every DSYNC overwrite IO
anymore.
Signed-Off-By: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>

Currently iomap_dio_rw() only handles (data)sync write completions
for AIO. This means we can't optimised non-AIO IO to minimise device
flushes as we can't tell the caller whether a flush is required or
not.

To solve this problem and enable further optimisations, make
iomap_dio_rw responsible for data sync behaviour for all IO, not
just AIO.

In doing so, the sync operation is now accounted as part of the DIO
IO by inode_dio_end(), hence post-IO data stability updates will no
long race against operations that serialise via inode_dio_wait()
such as truncate or hole punch.
Signed-Off-By: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>

To prepare for iomap iinfrastructure based DSYNC optimisations.

While moving the code araound, move the XFS write bytes metric
update for direct IO into xfs_dio_write_end_io callback so that we
always capture the amount of data written via AIO+DIO. This fixes
the problem where queued AIO+DIO writes are not accounted to this
metric.
Signed-Off-By: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>

When looking at an event trace recently, I noticed that non-blocking
buffer lookup attempts would fail on cached locked buffers and then
run the slow cache-miss path. This means we are doing an xfs_buf
allocation, lookup and free unnecessarily every time we avoid
blocking on a locked buffer.

Fix this by changing _xfs_buf_find() to return an error status to
the caller to indicate that we failed the lock attempt rather than
just returning a NULL. This allows the higher level code to
discriminate between a cache miss and an cache hit that we failed to
lock.

This also allows us to return a -EFSCORRUPTED state if we are asked
to look up a block number outside the range of the filesystem in
_xfs_buf_find(), which moves us one step closer to being able to
handle such errors in a more graceful manner at the higher levels.
Signed-Off-By: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NCarlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>

Move xfs_buf_incore out of line and make it the only way to look up
a buffer in the buffer cache from outside the buffer cache. Convert
the external users of _xfs_buf_find() to xfs_buf_incore() and make
_xfs_buf_find() static.
Signed-Off-By: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NCarlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
[darrick: actually rename xfs_incore -> xfs_buf_incore]
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>

This will trace i.e. the ATTR_SECURE/ATTR_CREATE/ATTR_REPLACE
flags as well as the OP_FLAGS.
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>

When we have corrupted free inode btrees, we can attempt to
allocate inodes that we know are already allocated. Catch allocation
of these inodes and report corruption as early as possible to
prevent corruption propagation or deadlocks.
Signed-Off-By: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NCarlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>

A recent fuzzed filesystem image cached random dcache corruption
when the reproducer was run. This often showed up as panics in
lookup_slow() on a null inode->i_ops pointer when doing pathwalks.

BUG: unable to handle kernel NULL pointer dereference at 0000000000000000
....
Call Trace:
 lookup_slow+0x44/0x60
 walk_component+0x3dd/0x9f0
 link_path_walk+0x4a7/0x830
 path_lookupat+0xc1/0x470
 filename_lookup+0x129/0x270
 user_path_at_empty+0x36/0x40
 path_listxattr+0x98/0x110
 SyS_listxattr+0x13/0x20
 do_syscall_64+0xf5/0x280
 entry_SYSCALL_64_after_hwframe+0x42/0xb7

but had many different failure modes including deadlocks trying to
lock the inode that was just allocated or KASAN reports of
use-after-free violations.

The cause of the problem was a corrupt INOBT on a v4 fs where the
root inode was marked as free in the inobt record. Hence when we
allocated an inode, it chose the root inode to allocate, found it in
the cache and re-initialised it.

We recently fixed a similar inode allocation issue caused by inobt
record corruption problem in xfs_iget_cache_miss() in commit
ee457001 ("xfs: catch inode allocation state mismatch
corruption"). This change adds similar checks to the cache-hit path
to catch it, and turns the reproducer into a corruption shutdown
situation.
Reported-by: NWen Xu <wen.xu@gatech.edu>
Signed-Off-By: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NCarlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
[darrick: fix typos in comment]
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>

Pll KVM fixes from Radim Krčmář:
 "ARM:
   - Fix proxying of GICv2 CPU interface accesses
   - Fix crash when switching to BE
   - Track source vcpu git GICv2 SGIs
   - Fix an outdated bit of documentation

  x86:
   - Speed up injection of expired timers (for stable)"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: x86: remove APIC Timer periodic/oneshot spikes
  arm64: vgic-v2: Fix proxying of cpuif access
  KVM: arm/arm64: vgic_init: Cleanup reference to process_maintenance
  KVM: arm64: Fix order of vcpu_write_sys_reg() arguments
  KVM: arm/arm64: vgic: Fix source vcpu issues for GICv2 SGI

Pull iommu fixes from Joerg Roedel:

 - fix a compile warning in the AMD IOMMU driver with irq remapping
   disabled

 - fix for VT-d interrupt remapping and invalidation size (caused a
   BUG_ON when trying to invalidate more than 4GB)

 - build fix and a regression fix for broken graphics with old DTS for
   the rockchip iommu driver

 - a revert in the PCI window reservation code which fixes a regression
   with VFIO.

* tag 'iommu-fixes-v4.17-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
  iommu: rockchip: fix building without CONFIG_OF
  iommu/vt-d: Use WARN_ON_ONCE instead of BUG_ON in qi_flush_dev_iotlb()
  iommu/vt-d: fix shift-out-of-bounds in bug checking
  iommu/dma: Move PCI window region reservation back into dma specific path.
  iommu/rockchip: Make clock handling optional
  iommu/amd: Hide unused iommu_table_lock
  iommu/vt-d: Fix usage of force parameter in intel_ir_reconfigure_irte()

Pull x86 fix from Thomas Gleixner:
 "Unbreak the CPUID CPUID_8000_0008_EBX reload which got dropped when
  the evaluation of physical and virtual bits which uses the same CPUID
  leaf was moved out of get_cpu_cap()"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/cpu: Restore CPUID_8000_0008_EBX reload

Pull clocksource fixes from Thomas Gleixner:
 "The recent addition of the early TSC clocksource breaks on machines
  which have an unstable TSC because in case that TSC is disabled, then
  the clocksource selection logic falls back to the early TSC which is
  obviously bogus.

  That also unearthed a few robustness issues in the clocksource
  derating code which are addressed as well"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  clocksource: Rework stale comment
  clocksource: Consistent de-rate when marking unstable
  x86/tsc: Fix mark_tsc_unstable()
  clocksource: Initialize cs->wd_list
  clocksource: Allow clocksource_mark_unstable() on unregistered clocksources
  x86/tsc: Always unregister clocksource_tsc_early

Pull irq fix from Thomas Gleixner:
 "A single fix to prevent false positives in the spurious interrupt
  detector when more than a single demultiplex register is evaluated in
  the Qualcom irq combiner driver"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip/qcom: Fix check for spurious interrupts

Pull x86 platform driver fixes from Darren Hart:

 - We missed a case in the Dell config dependencies resulting in a
   possible bad configuration, resolve it by giving up on trying to keep
   DELL_LAPTOP visible in the menu and make it depend on DELL_SMBIOS.

 - Fix a null pointer dereference at module unload for the asus-wireless
   driver.

* tag 'platform-drivers-x86-v4.17-2' of git://git.infradead.org/linux-platform-drivers-x86:
  platform/x86: Kconfig: Fix dell-laptop dependency chain.
  platform/x86: asus-wireless: Fix NULL pointer dereference

Pull USB fixes from Greg KH:
 "Here are some USB driver fixes for 4.17-rc4.

  The majority of them are some USB gadget fixes that missed my last
  pull request. The "largest" patch in here is a fix for the old visor
  driver that syzbot found 6 months or so ago and I finally remembered
  to fix it.

  All of these have been in linux-next with no reported issues"

* tag 'usb-4.17-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
  Revert "usb: host: ehci: Use dma_pool_zalloc()"
  usb: typec: tps6598x: handle block reads separately with plain-I2C adapters
  usb: typec: tcpm: Release the role mux when exiting
  USB: Accept bulk endpoints with 1024-byte maxpacket
  xhci: Fix use-after-free in xhci_free_virt_device
  USB: serial: visor: handle potential invalid device configuration
  USB: serial: option: adding support for ublox R410M
  usb: musb: trace: fix NULL pointer dereference in musb_g_tx()
  usb: musb: host: fix potential NULL pointer dereference
  usb: gadget: composite Allow for larger configuration descriptors
  usb: dwc3: gadget: Fix list_del corruption in dwc3_ep_dequeue
  usb: dwc3: gadget: dwc3_gadget_del_and_unmap_request() can be static
  usb: dwc2: pci: Fix error return code in dwc2_pci_probe()
  usb: dwc2: WA for Full speed ISOC IN in DDMA mode.
  usb: dwc2: dwc2_vbus_supply_init: fix error check
  usb: gadget: f_phonet: fix pn_net_xmit()'s return type

Since the commit "8003c9ae: add APIC Timer periodic/oneshot mode VMX
preemption timer support", a Windows 10 guest has some erratic timer
spikes.

Here the results on a 150000 times 1ms timer without any load:
	  Before 8003c9ae | After 8003c9ae
Max           1834us          |  86000us
Mean          1100us          |   1021us
Deviation       59us          |    149us
Here the results on a 150000 times 1ms timer with a cpu-z stress test:
	  Before 8003c9ae | After 8003c9ae
Max          32000us          | 140000us
Mean          1006us          |   1997us
Deviation      140us          |  11095us

The root cause of the problem is starting hrtimer with an expiry time
already in the past can take more than 20 milliseconds to trigger the
timer function.  It can be solved by forward such past timers
immediately, rather than submitting them to hrtimer_start().
In case the timer is periodic, update the target expiration and call
hrtimer_start with it.

v2: Check if the tsc deadline is already expired. Thank you Mika.
v3: Execute the past timers immediately rather than submitting them to
hrtimer_start().
v4: Rearm the periodic timer with advance_periodic_target_expiration() a
simpler version of set_target_expiration(). Thank you Paolo.

Cc: Mika Penttilä <mika.penttila@nextfour.com>
Cc: Wanpeng Li <kernellwp@gmail.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: NAnthoine Bourgeois <anthoine.bourgeois@blade-group.com>
8003c9ae ("KVM: LAPIC: add APIC Timer periodic/oneshot mode VMX preemption timer support")
Signed-off-by: NRadim Krčmář <rkrcmar@redhat.com>

KVM/arm fixes for 4.17, take #2

- Fix proxying of GICv2 CPU interface accesses
- Fix crash when switching to BE
- Track source vcpu git GICv2 SGIs
- Fix an outdated bit of documentation

Merge tag 'kbuild-fixes-v4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild fixes from Masahiro Yamada:

 - remove state comment in modpost

 - extend MAINTAINERS entry to cover modpost and more makefiles

 - fix missed building of SANCOV gcc-plugin

 - replace left-over 'bison' with $(YACC)

 - display short log when generating parer of genksyms

* tag 'kbuild-fixes-v4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  genksyms: fix typo in parse.tab.{c,h} generation rules
  kbuild: replace hardcoded bison in cmd_bison_h with $(YACC)
  gcc-plugins: fix build condition of SANCOV plugin
  MAINTAINERS: Update Kbuild entry with a few paths
  modpost: delete stale comment

Pull clk fixes froom Stephen Boyd:
 "A handful of fixes for the stm32mp1 clk driver came in during the
  merge window for the driver that got merged in the merge window.

  Plus a warning fix for unused PM ops and a couple fixes for the meson
  clk driver clk names that went unnoticed with the regmap rework.

  There's also another fix in here for the mux rounding flag which
  wasn't doing what it said it did, but now it does"

* tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux:
  clk: meson: meson8b: fix meson8b_cpu_clk parent clock name
  clk: meson: meson8b: fix meson8b_fclk_div3_div clock name
  clk: meson: drop meson_aoclk_gate_regmap_ops
  clk: meson: honor CLK_MUX_ROUND_CLOSEST in clk_regmap
  clk: honor CLK_MUX_ROUND_CLOSEST in generic clk mux
  clk: cs2000: mark resume function as __maybe_unused
  clk: stm32mp1: remove ck_apb_dbg clock
  clk: stm32mp1: set stgen_k clock as critical
  clk: stm32mp1: add missing tzc2 clock
  clk: stm32mp1: fix SAI3 & SAI4 clocks
  clk: stm32mp1: remove unused dfsdm_src[] const
  clk: stm32mp1: add missing static

Pull remoteproc and rpmsg fixes from Bjorn Andersson:

 - fix screw-up when reversing boolean for rproc_stop()

 - add missing OF node refcounting dereferences

 - add missing MODULE_ALIAS in rpmsg_char

* tag 'rproc-v4.17-1' of git://github.com/andersson/remoteproc:
  rpmsg: added MODULE_ALIAS for rpmsg_char
  remoteproc: qcom: Fix potential device node leaks
  remoteproc: fix crashed parameter logic on stop call

Pull drm fixes from Dave Airlie:
 "vmwgfx, i915, vc4, vga dac fixes.

  This seems eerily quiet, so I expect it will explode next week or
  something.

  One i915 model firmware, two vmwgfx fixes, one vc4 fix and one bridge
  leak fix"

* tag 'drm-fixes-for-v4.17-rc4' of git://people.freedesktop.org/~airlied/linux:
  drm/bridge: vga-dac: Fix edid memory leak
  drm/vc4: Make sure vc4_bo_{inc,dec}_usecnt() calls are balanced
  drm/i915/glk: Add MODULE_FIRMWARE for Geminilake
  drm/vmwgfx: Fix a buffer object leak
  drm/vmwgfx: Clean up fbdev modeset locking

Pull tracing fixes from Steven Rostedt:
 "Some of the files in the tracing directory show file mode 0444 when
  they are writable by root. To fix the confusion, they should be 0644.
  Note, either case root can still write to them.

  Zhengyuan asked why I never applied that patch (the first one is from
  2014!). I simply forgot about it. /me lowers head in shame"

* tag 'trace-v4.17-rc1-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Fix the file mode of stack tracer
  ftrace: Have set_graph_* files have normal file modes