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blk_mq_unquiesce_queue() is used for unquiescing the
queue explicitly, so replace blk_mq_start_stopped_hw_queues()
with it.
For the scsi part, this patch takes Bart's suggestion to
switch to block quiesce/unquiesce API completely.
Cc: linux-nvme@lists.infradead.org
Cc: linux-scsi@vger.kernel.org
Cc: dm-devel@redhat.com
Reviewed-by: Bart Van Assche <Bart.VanAssche@sandisk.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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blk_mq_start_stopped_hw_queues() is used implictly
as counterpart of blk_mq_quiesce_queue() for unquiescing queue,
so we introduce blk_mq_unquiesce_queue() and make it
as counterpart of blk_mq_quiesce_queue() explicitly.
This function is for improving the current quiescing mechanism
in the following patches.
Reviewed-by: Bart Van Assche <Bart.VanAssche@sandisk.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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This patch introduces blk_mq_quiesce_queue_nowait() so
that we can workaround mpt3sas for quiescing its queue.
Once mpt3sas is fixed, we can remove this helper.
Reviewed-by: Bart Van Assche <Bart.VanAssche@sandisk.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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We usually put blk_mq_*() into include/linux/blk-mq.h, so
move this API into there.
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Bart Van Assche <Bart.VanAssche@sandisk.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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virtio balloon bypasses the DMA API entirely so does not support the
VIOMMU right now. It's not clear we need that support, for now let's
just make sure we don't pretend to support it.
Cc: stable@vger.kernel.org
Cc: Wei Wang <wei.w.wang@intel.com>
Fixes: 1a937693993f ("virtio: new feature to detect IOMMU device quirk")
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
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blk_bio_segment_split() makes sure bios have no more than
BIO_MAX_PAGES entries in the bi_io_vec.
This was done because bio_clone_bioset() (when given a
mempool bioset) could not handle larger io_vecs.
No driver uses bio_clone_bioset() any more, they all
use bio_clone_fast() if anything, and bio_clone_fast()
doesn't clone the bi_io_vec.
The main user of of bio_clone_bioset() at this level
is bounce.c, and bouncing now happens before blk_bio_segment_split(),
so that is not of concern.
So remove the big helpful comment and the code.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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bio_clone() is no longer used.
Only bio_clone_bioset() or bio_clone_fast().
This is for the best, as bio_clone() used fs_bio_set,
and filesystems are unlikely to want to use bio_clone().
So remove bio_clone() and all references.
This includes a fix to some incorrect documentation.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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This function allocates a bio, then a collection
of pages. It copes with failure.
It currently uses a mempool() to allocate the bio,
but alloc_page() to allocate the pages. These fail
in different ways, so the usage is inconsistent.
Change the bio_clone() to bio_clone_kmalloc()
so that no pool is used either for the bio or the pages.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Kent Overstreet <kent.overstreet@gmail.com>
Reviewed-by : Ming Lei <ming.lei@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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bios that are re-submitted will pass through blk_queue_split() when
blk_queue_bio() is called, and this will split the bio if necessary.
There is no longer any need to do this splitting in xen-blkfront.
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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pblk_submit_read() uses bio_clone_bioset() but doesn't change the
io_vec, so bio_clone_fast() is a better choice.
It also uses fs_bio_set which is intended for filesystems. Using it
in a device driver can deadlock.
So allocate a new bioset, and and use bio_clone_fast().
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Javier González <javier@cnexlabs.com>
Tested-by: Javier González <javier@cnexlabs.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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pktcdvd doesn't change the bi_io_vec of the clone bio,
so it is more efficient to use bio_clone_fast(), and not clone
the bi_io_vec.
This requires providing a bio_set, and it is safest to
provide a dedicated bio_set rather than sharing
fs_bio_set, which filesytems use.
This new bio_set, pkt_bio_set, can also be use for the bio_split()
call as the two allocations (bio_clone_fast, and bio_split) are
independent, neither can block a bio allocated by the other.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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drbd does not modify the bi_io_vec of the cloned bio,
so there is no need to clone that part. So bio_clone_fast()
is the better choice.
For bio_clone_fast() we need to specify a bio_set.
We could use fs_bio_set, which bio_clone() uses, or
drbd_md_io_bio_set, which drbd uses for metadata, but it is
generally best to avoid sharing bio_sets unless you can
be certain that there are no interdependencies.
So create a new bio_set, drbd_io_bio_set, and use bio_clone_fast().
Also remove a "XXX cannot fail ???" comment because it definitely
cannot fail - bio_clone_fast() doesn't fail if the GFP flags allow for
sleeping.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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bio_clone() makes a copy of the bi_io_vec, but rbd never changes that,
so there is no need for a copy.
bio_clone_fast() can be used instead, which avoids making the copy.
This requires that we provide a bio_set. bio_clone() uses fs_bio_set,
but it isn't, in general, safe to use the same bio_set at different
levels of the stack, as that can lead to deadlocks. As filesystems
use fs_bio_set, block devices shouldn't.
As rbd never stacks, it is safe to have a single global bio_set for
all rbd devices to use. So allocate that when the module is
initialised, and use it with bio_clone_fast().
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Since commit 23688bf4f830 ("block: ensure to split after potentially
bouncing a bio") blk_queue_bounce() is called *before*
blk_queue_split().
This means that:
1/ the comments blk_queue_split() about bounce buffers are
irrelevant, and
2/ a very large bio (more than BIO_MAX_PAGES) will no longer be
split before it arrives at blk_queue_bounce(), leading to the
possibility that bio_clone_bioset() will fail and a NULL
will be dereferenced.
Separately, blk_queue_bounce() shouldn't use fs_bio_set as the bio
being copied could be from the same set, and this could lead to a
deadlock.
So:
- allocate 2 private biosets for blk_queue_bounce, one for
splitting enormous bios and one for cloning bios.
- add code to split a bio that exceeds BIO_MAX_PAGES.
- Fix up the comments in blk_queue_split()
Credit-to: Ming Lei <tom.leiming@gmail.com> (suggested using single bio_for_each_segment loop)
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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A rescuing bioset is only useful if there might be bios from
that same bioset on the bio_list_on_stack queue at a time
when bio_alloc_bioset() is called. This never applies to
q->bio_split.
Allocations from q->bio_split are only ever made from
blk_queue_split() which is only ever called early in each of
various make_request_fn()s. The original bio (call this A)
is then passed to generic_make_request() and is placed on
the bio_list_on_stack queue, and the bio that was allocated
from q->bio_split (B) is processed.
The processing of this may cause other bios to be passed to
generic_make_request() or may even cause the bio B itself to
be passed, possible after some prefix has been split off
(using some other bioset).
generic_make_request() now guarantees that all of these bios
(B and dependants) will be fully processed before the tail
of the original bio A gets handled. None of these early bios
can possible trigger an allocation from the original
q->bio_split as they are either too small to require
splitting or (more likely) are destined for a different queue.
The next time that the original q->bio_split might be used
by this thread is when A is processed again, as it might
still be too big to handle directly. By this time there
cannot be any other bios allocated from q->bio_split in the
generic_make_request() queue. So no rescuing will ever be
needed.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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This patch converts bioset_create() to not create a workqueue by
default, so alloctions will never trigger punt_bios_to_rescuer(). It
also introduces a new flag BIOSET_NEED_RESCUER which tells
bioset_create() to preserve the old behavior.
All callers of bioset_create() that are inside block device drivers,
are given the BIOSET_NEED_RESCUER flag.
biosets used by filesystems or other top-level users do not
need rescuing as the bio can never be queued behind other
bios. This includes fs_bio_set, blkdev_dio_pool,
btrfs_bioset, xfs_ioend_bioset, and one allocated by
target_core_iblock.c.
biosets used by md/raid do not need rescuing as
their usage was recently audited and revised to never
risk deadlock.
It is hoped that most, if not all, of the remaining biosets
can end up being the non-rescued version.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Credit-to: Ming Lei <ming.lei@redhat.com> (minor fixes)
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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"flags" arguments are often seen as good API design as they allow
easy extensibility.
bioset_create_nobvec() is implemented internally as a variation in
flags passed to __bioset_create().
To support future extension, make the internal structure part of the
API.
i.e. add a 'flags' argument to bioset_create() and discard
bioset_create_nobvec().
Note that the bio_split allocations in drivers/md/raid* do not need
the bvec mempool - they should have used bioset_create_nobvec().
Suggested-by: Christoph Hellwig <hch@infradead.org>
Reviewed-by: Christoph Hellwig <hch@infradead.org>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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blk_queue_split() is always called with the last arg being q->bio_split,
where 'q' is the first arg.
Also blk_queue_split() sometimes uses the passed-in 'bs' and sometimes uses
q->bio_split.
This is inconsistent and unnecessary. Remove the last arg and always use
q->bio_split inside blk_queue_split()
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Credit-to: Javier González <jg@lightnvm.io> (Noticed that lightnvm was missed)
Reviewed-by: Javier González <javier@cnexlabs.com>
Tested-by: Javier González <javier@cnexlabs.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Move most code into blk_mq_rq_ctx_init, and the rest into
blk_mq_get_request.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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This patch makes sure we always allocate requests in the core blk-mq
code and use a common prepare_request method to initialize them for
both mq I/O schedulers. For Kyber and additional limit_depth method
is added that is called before allocating the request.
Also because none of the intializations can really fail the new method
does not return an error - instead the bfq finish method is hardened
to deal with the no-IOC case.
Last but not least this removes the abuse of RQF_QUEUE by the blk-mq
scheduling code as RQF_ELFPRIV is all that is needed now.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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blk_mq_sched_assign_ioc now only handles the assigned of the ioc if
the schedule needs it (bfq only at the moment). The caller to the
per-request initializer is moved out so that it can be merged with
a similar call for the kyber I/O scheduler.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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icq_to_bic is a container_of operation, so we need to check for NULL
before it. Also move the check outside the spinlock while we're at
it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Merge three functions only tail-called by blk_mq_free_request into
blk_mq_free_request.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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No need to have two different callouts of bfq vs kyber.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Having these as separate helpers in a header really does not help
readability, or my chances to refactor this code sanely.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Having them out of line in blk-mq-sched.c just makes the code flow
unnecessarily complicated.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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When a filesystem is mounted from a loop device, writes are
throttled by balance_dirty_pages() twice: once when writing
to the filesystem and once when the loop_handle_cmd() writes
to the backing file. This double-throttling can trigger
positive feedback loops that create significant delays. The
throttling at the lower level is seen by the upper level as
a slow device, so it throttles extra hard.
The PF_LESS_THROTTLE flag was created to handle exactly this
circumstance, though with an NFS filesystem mounted from a
local NFS server. It reduces the throttling on the lower
layer so that it can proceed largely unthrottled.
To demonstrate this, create a filesystem on a loop device
and write (e.g. with dd) several large files which combine
to consume significantly more than the limit set by
/proc/sys/vm/dirty_ratio or dirty_bytes. Measure the total
time taken.
When I do this directly on a device (no loop device) the
total time for several runs (mkfs, mount, write 200 files,
umount) is fairly stable: 28-35 seconds.
When I do this over a loop device the times are much worse
and less stable. 52-460 seconds. Half below 100seconds,
half above.
When I apply this patch, the times become stable again,
though not as fast as the no-loop-back case: 53-72 seconds.
There may be room for further improvement as the total overhead still
seems too high, but this is a big improvement.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ming Lei <tom.leiming@gmail.com>
Suggested-by: Michal Hocko <mhocko@suse.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Thomas Gleixner:
"Two fixlets for x86:
- Handle WARN_ONs proper with the new UD based WARN implementation
- Disable 1G mappings when 2M mappings are disabled by kmemleak or
debug_pagealloc. Otherwise 1G mappings might still be used,
confusing the debug mechanisms"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mm: Disable 1GB direct mappings when disabling 2MB mappings
x86/debug: Handle early WARN_ONs proper
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fixes from Thomas Gleixner:
"Three fixlets for timers:
- Two hot-fixes for the alarmtimer based posix timers, which prevent
a nasty DOS by self rescheduling timers. The proper cleanup of that
mess is queued for 4.13
- Make a function static"
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
tick/broadcast: Make tick_broadcast_setup_oneshot() static
alarmtimer: Rate limit periodic intervals
alarmtimer: Prevent overflow of relative timers
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Thomas Gleixner:
"Two small fixes for the schedulre core:
- Use the proper switch_mm() variant in idle_task_exit() because that
code is not called with interrupts disabled.
- Fix a confusing typo in a printk"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/core: Idle_task_exit() shouldn't use switch_mm_irqs_off()
sched/fair: Fix typo in printk message
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Thomas Gleixner:
"Three fixes for the perf user space side:
- Fix the probing of precise_ip level, which got broken recently for
x86.
- Unbreak the ARCH=x86_64 build
- Report module before trying to unwind into the module code, which
avoids broken stack frames displayed"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf unwind: Report module before querying isactivation in dwfl unwind
perf tools: Fix build with ARCH=x86_64
perf evsel: Fix probing of precise_ip level for default cycles event
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq fix from Thomas Gleixner:
"Add a missing resource release to an error path"
* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
genirq: Release resources in __setup_irq() error path
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull objtool fix from Thomas Gleixner:
"A single fix which adds fortify_panic to the list of no return
functions"
* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
objtool: Add fortify_panic as __noreturn function
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git://git.kernel.org/pub/scm/linux/kernel/git/j.anaszewski/linux-leds
Pull LED fixes from Jacek Anaszewski:
"Two LED fixes:
- fix signal source assignment for leds-bcm6328
- revert patch that intended to fix LED behavior on suspend but it
had a side effect preventing suspend at all due to uevent being
sent on trigger removal"
* tag 'led_fixes_for_4.12-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/j.anaszewski/linux-leds:
Revert "leds: handle suspend/resume in heartbeat trigger"
leds: bcm6328: fix signal source assignment for leds 4 to 7
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git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
Pull USB fixes from Greg KH:
"Here are some small gadget and xhci USB fixes for 4.12-rc6.
Nothing major, but one of the gadget patches does fix a reported oops,
and the xhci ones resolve reported problems. All have been in
linux-next with no reported issues"
* tag 'usb-4.12-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
USB: gadgetfs, dummy-hcd, net2280: fix locking for callbacks
usb: xhci: ASMedia ASM1042A chipset need shorts TX quirk
usb: xhci: Fix USB 3.1 supported protocol parsing
USB: gadget: fix GPF in gadgetfs
usb: gadget: composite: make sure to reactivate function on unbind
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git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging
Pull staging and IIO fixes from Greg KH:
"Here are some small staging and IIO driver fixes for 4.12-rc6.
Nothing huge, just a few small driver fixes for reported issues. All
have been in linux-next with no reported issues"
* tag 'staging-4.12-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
Staging: rtl8723bs: fix an error code in isFileReadable()
iio: buffer-dmaengine: Add missing header buffer_impl.h
iio: buffer-dma: Add missing header buffer_impl.h
iio: adc: meson-saradc: fix potential crash in meson_sar_adc_clear_fifo
iio: adc: mxs-lradc: Fix return value check in mxs_lradc_adc_probe()
iio: imu: inv_mpu6050: add accel lpf setting for chip >= MPU6500
staging: iio: ad7152: Fix deadlock in ad7152_write_raw_samp_freq()
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Pull ceph fixes from Ilya Dryomov:
"A fix for an old ceph ->fh_to_* bug from Luis and two timestamp fixups
from Zheng, prompted by the ongoing y2038 work"
* tag 'ceph-for-4.12-rc6' of git://github.com/ceph/ceph-client:
ceph: unify inode i_ctime update
ceph: use current_kernel_time() to get request time stamp
ceph: check i_nlink while converting a file handle to dentry
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* original hysteresis loop got broken by typo back in 2002; now
it never switches out of OPTTIME state. Fixed.
* critical levels for switching from OPTTIME to OPTSPACE and back
ought to be calculated once, at mount time.
* we should use mul_u64_u32_div() for those calculations, now that
->s_dsize is 64bit.
* to quote Kirk McKusick (in 1995 FreeBSD commit message):
The threshold for switching from time-space and space-time is too small
when minfree is 5%...so make it stay at space in this case.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Thomas Gleixner wrote:
> The CRIU support added a 'feature' which allows a user space task to send
> arbitrary (kernel) signals to itself. The changelog says:
>
> The kernel prevents sending of siginfo with positive si_code, because
> these codes are reserved for kernel. I think we can allow a task to
> send such a siginfo to itself. This operation should not be dangerous.
>
> Quite contrary to that claim, it turns out that it is outright dangerous
> for signals with info->si_code == SI_TIMER. The following code sequence in
> a user space task allows to crash the kernel:
>
> id = timer_create(CLOCK_XXX, ..... signo = SIGX);
> timer_set(id, ....);
> info->si_signo = SIGX;
> info->si_code = SI_TIMER:
> info->_sifields._timer._tid = id;
> info->_sifields._timer._sys_private = 2;
> rt_[tg]sigqueueinfo(..., SIGX, info);
> sigemptyset(&sigset);
> sigaddset(&sigset, SIGX);
> rt_sigtimedwait(sigset, info);
>
> For timers based on CLOCK_PROCESS_CPUTIME_ID, CLOCK_THREAD_CPUTIME_ID this
> results in a kernel crash because sigwait() dequeues the signal and the
> dequeue code observes:
>
> info->si_code == SI_TIMER && info->_sifields._timer._sys_private != 0
>
> which triggers the following callchain:
>
> do_schedule_next_timer() -> posix_cpu_timer_schedule() -> arm_timer()
>
> arm_timer() executes a list_add() on the timer, which is already armed via
> the timer_set() syscall. That's a double list add which corrupts the posix
> cpu timer list. As a consequence the kernel crashes on the next operation
> touching the posix cpu timer list.
>
> Posix clocks which are internally implemented based on hrtimers are not
> affected by this because hrtimer_start() can handle already armed timers
> nicely, but it's a reliable way to trigger the WARN_ON() in
> hrtimer_forward(), which complains about calling that function on an
> already armed timer.
This problem has existed since the posix timer code was merged into
2.5.63. A few releases earlier in 2.5.60 ptrace gained the ability to
inject not just a signal (which linux has supported since 1.0) but the
full siginfo of a signal.
The core problem is that the code will reschedule in response to
signals getting dequeued not just for signals the timers sent but
for other signals that happen to a si_code of SI_TIMER.
Avoid this confusion by testing to see if the queued signal was
preallocated as all timer signals are preallocated, and so far
only the timer code preallocates signals.
Move the check for if a timer needs to be rescheduled up into
collect_signal where the preallocation check must be performed,
and pass the result back to dequeue_signal where the code reschedules
timers. This makes it clear why the code cares about preallocated
timers.
Cc: stable@vger.kernel.org
Reported-by: Thomas Gleixner <tglx@linutronix.de>
History Tree: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git
Reference: 66dd34ad31e5 ("signal: allow to send any siginfo to itself")
Reference: 1669ce53e2ff ("Add PTRACE_GETSIGINFO and PTRACE_SETSIGINFO")
Fixes: db8b50ba75f2 ("[PATCH] POSIX clocks & timers")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
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Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Pull xfs fix from Darrick Wong:
"One more bugfix for you for 4.12-rc6 to fix something that came up in
an earlier rc:
- Fix some bogus ASSERT failures on CONFIG_SMP=n and CONFIG_XFS_DEBUG=y"
* tag 'xfs-4.12-fixes-4' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
xfs: fix spurious spin_is_locked() assert failures on non-smp kernels
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git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull ufs fixes from Al Viro:
"Fix assorted ufs bugs: a couple of deadlocks, fs corruption in
truncate(), oopsen on tail unpacking and truncate when racing with
vmscan, mild fs corruption (free blocks stats summary buggered, *BSD
fsck would complain and fix), several instances of broken logics
around reserved blocks (starting with "check almost never triggers
when it should" and then there are issues with sufficiently large
UFS2)"
[ Note: ufs hasn't gotten any loving in a long time, because nobody
really seems to use it. These ufs fixes are triggered by people
actually caring now, not some sudden influx of new bugs. - Linus ]
* 'ufs-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
ufs_truncate_blocks(): fix the case when size is in the last direct block
ufs: more deadlock prevention on tail unpacking
ufs: avoid grabbing ->truncate_mutex if possible
ufs_get_locked_page(): make sure we have buffer_heads
ufs: fix s_size/s_dsize users
ufs: fix reserved blocks check
ufs: make ufs_freespace() return signed
ufs: fix logics in "ufs: make fsck -f happy"
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git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs fixes from Al Viro:
"A couple of fixes; a leak in mntns_install() caught by Andrei (this
cycle regression) + d_invalidate() softlockup fix - that had been
reported by a bunch of people lately, but the problem is pretty old"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
fs: don't forget to put old mntns in mntns_install
Hang/soft lockup in d_invalidate with simultaneous calls
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git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci
Pull PCI fixes from Bjorn Helgaas:
- fix another PCI_ENDPOINT build error (merged for v4.12)
- fix error codes added to config accessors for v4.12
* tag 'pci-v4.12-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
PCI: endpoint: Select CRC32 to fix test build error
PCI: Make error code types consistent in pci_{read,write}_config_*
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Pull fbdev fixes from Bartlomiej Zolnierkiewicz:
- fix udlfb driver to stop spamming logs (Mike Gerow)
- add missing endianness conversions in smscufx & udlfb drivers (Johan
Hovold)
- fix few gcc warnings/errors (Arnd Bergmann)
* tag 'fbdev-v4.12-rc6' of git://github.com/bzolnier/linux:
video: fbdev: udlfb: drop log level for blanking
video: fbdev: via: remove possibly unused variables
video: fbdev: add missing USB-descriptor endianness conversions
video: fbdev: avoid int-in-bool-context warning
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Merge misc fixes from Andrew Morton:
"5 fixes"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
mm: correct the comment when reclaimed pages exceed the scanned pages
userfaultfd: shmem: handle coredumping in handle_userfault()
mm: numa: avoid waiting on freed migrated pages
swap: cond_resched in swap_cgroup_prepare()
mm/memory-failure.c: use compound_head() flags for huge pages
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Commit e1587a494540 ("mm: vmpressure: fix sending wrong events on
underflow") declared that reclaimed pages exceed the scanned pages due
to the thp reclaim.
That is incorrect because THP will be spilt to normal page and loop
again, which will result in the scanned pages increment.
[akpm@linux-foundation.org: tweak comment text]
Link: http://lkml.kernel.org/r/1496824266-25235-1-git-send-email-zhongjiang@huawei.com
Signed-off-by: zhongjiang <zhongjiang@huawei.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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