Some parts of the code assumed that get_ldev_if_state(device, D_ATTACHING)
is sufficient to access the ldev member of the device object. That was
wrong. ldev may not be there or might be freed at any time if the device
has a disk state of D_ATTACHING.
bm_rw()
Documented that drbd_bm_read() is only called from drbd_adm_attach.
drbd_bm_write() is only called when a reference is held, and it is
documented that a caller has to hold a reference before calling
drbd_bm_write()
drbd_bm_write_page()
Use get_ldev() instead of get_ldev_if_state(device, D_ATTACHING)
drbd_bmio_set_n_write()
No longer use get_ldev_if_state(device, D_ATTACHING). All callers
hold a reference to ldev now.
drbd_bmio_clear_n_write()
All callers where holding a reference of ldev anyways. Remove the
misleading get_ldev_if_state(device, D_ATTACHING)
drbd_reconsider_max_bio_size()
Removed the get_ldev_if_state(device, D_ATTACHING). All callers
now pass a struct drbd_backing_dev* when they have a proper
reference, or a NULL pointer.
Before this fix, the receiver could trigger a NULL pointer
deref when in drbd_reconsider_max_bio_size()
drbd_bump_write_ordering()
Used get_ldev_if_state(device, D_ATTACHING) with the wrong assumption.
Remove it, and allow the caller to pass in a struct drbd_backing_dev*
when the caller knows that accessing this bdev is safe.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Firstly this patch supports more than one virtual queues for virtio-blk
device.
Secondly this patch maps the virtual queue to blk-mq's hardware queue.
With this approach, both scalability and performance can be improved.
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Current virtio-blk spec only supports one virtual queue for transfering
data between VM and host, and inside VM all kinds of operations on
the virtual queue needs to hold one lock, so cause below problems:
- bad scalability
- bad throughput
This patch requests to introduce feature of VIRTIO_BLK_F_MQ
so that more than one virtual queues can be used to virtio-blk
device, then above problems can be solved or eased.
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
After the SG_IO ioctl was copied into the block layer and
later into the bsg driver, subtle differences emerged.
One difference is the way injected commands are queued through
the block layer (i.e. this is not SCSI device queueing nor SATA
NCQ). Summarizing:
- SG_IO on block layer device: blk_exec*(at_head=false)
- sg device SG_IO: at_head=true
- bsg device SG_IO: at_head=true
Some time ago Boaz Harrosh introduced a sg v4 flag called
BSG_FLAG_Q_AT_TAIL to override the bsg driver default. A
recent patch titled: "sg: add SG_FLAG_Q_AT_TAIL flag"
allowed the sg driver default to be overridden. This patch
allows a SG_IO ioctl sent to a block layer device to have
its default overridden.
ChangeLog:
- introduce SG_FLAG_Q_AT_HEAD flag in sg.h to cause
commands that are injected via a block layer
device SG_IO ioctl to set at_head=true
- make comments clearer about queueing in sg.h since the
header is used both by the sg device and block layer
device implementations of the SG_IO ioctl.
- introduce BSG_FLAG_Q_AT_HEAD in bsg.h for compatibility
(it does nothing) and update comments.
Signed-off-by: Douglas Gilbert <dgilbert@interlog.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: Jens Axboe <axboe@fb.com>
SG_GET_RESERVED_SIZE and SG_SET_RESERVED_SIZE ioctls access a reserved
buffer in bytes as int type. The value needs to be capped at the request
queue's max_sectors. But integer overflow is not correctly handled in
the calculation when converting max_sectors from sectors to bytes.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: "James E.J. Bottomley" <JBottomley@parallels.com>
Cc: Douglas Gilbert <dgilbert@interlog.com>
Cc: linux-scsi@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
BLKSECTGET ioctl loads the request queue's max_sectors as unsigned
short value to the argument pointer. So if the max_sector is greater
than USHRT_MAX, the upper 16 bits of that is just discarded.
In such case, USHRT_MAX is more preferable than the lower 16 bits of
max_sectors.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: "James E.J. Bottomley" <JBottomley@parallels.com>
Cc: Douglas Gilbert <dgilbert@interlog.com>
Cc: linux-scsi@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
checkpatch fixing:
WARNING: Missing a blank line after declarations
WARNING: space prohibited between function name and open parenthesis '('
ERROR: spaces required around that '<' (ctx:VxV)
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Jens Axboe <axboe@fb.com>
Also add no prefix pr_fmt to avoid any future default format update
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Jens Axboe <axboe@fb.com>
Commit 08778795 ("block: Fix nr_vecs for inline integrity vectors") from
Martin introduces the function bip_integrity_vecs(get the useful vectors)
to fix the issue about nr_vecs for inline integrity vectors that reported
by David Milburn.
But it seems that bip_integrity_vecs() will return the wrong number if the
bio is not based on any bio_set for some reason(bio->bi_pool == NULL),
because in that case, the bip_inline_vecs[0] is malloced directly. So
here we add the bip_max_vcnt to record the count of vector slots, and
cleanup the function bip_integrity_vecs().
Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Kent Overstreet <kmo@daterainc.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Currently, blk-mq uses a percpu_counter to keep track of how many
usages are in flight. The percpu_counter is drained while freezing to
ensure that no usage is left in-flight after freezing is complete.
blk_mq_queue_enter/exit() and blk_mq_[un]freeze_queue() implement this
per-cpu gating mechanism.
This type of code has relatively high chance of subtle bugs which are
extremely difficult to trigger and it's way too hairy to be open coded
in blk-mq. percpu_ref can serve the same purpose after the recent
changes. This patch replaces the open-coded per-cpu usage counting
and draining mechanism with percpu_ref.
blk_mq_queue_enter() performs tryget_live on the ref and exit()
performs put. blk_mq_freeze_queue() kills the ref and waits until the
reference count reaches zero. blk_mq_unfreeze_queue() revives the ref
and wakes up the waiters.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Nicholas A. Bellinger <nab@linux-iscsi.org>
Cc: Kent Overstreet <kmo@daterainc.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Keeping __blk_mq_drain_queue() as a separate function doesn't buy us
anything and it's gonna be further simplified. Let's flatten it into
its caller.
This patch doesn't make any functional change.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Nicholas A. Bellinger <nab@linux-iscsi.org>
Signed-off-by: Jens Axboe <axboe@fb.com>
blk_mq freezing is entangled with generic bypassing which bypasses
blkcg and io scheduler and lets IO requests fall through the block
layer to the drivers in FIFO order. This allows forward progress on
IOs with the advanced features disabled so that those features can be
configured or altered without worrying about stalling IO which may
lead to deadlock through memory allocation.
However, generic bypassing doesn't quite fit blk-mq. blk-mq currently
doesn't make use of blkcg or ioscheds and it maps bypssing to
freezing, which blocks request processing and drains all the in-flight
ones. This causes problems as bypassing assumes that request
processing is online. blk-mq works around this by conditionally
allowing request processing for the problem case - during queue
initialization.
Another weirdity is that except for during queue cleanup, bypassing
started on the generic side prevents blk-mq from processing new
requests but doesn't drain the in-flight ones. This shouldn't break
anything but again highlights that something isn't quite right here.
The root cause is conflating blk-mq freezing and generic bypassing
which are two different mechanisms. The only intersecting purpose
that they serve is during queue cleanup. Let's properly separate
blk-mq freezing from generic bypassing and simply use it where
necessary.
* request_queue->mq_freeze_depth is added and
blk_mq_[un]freeze_queue() now operate on this counter instead of
->bypass_depth. The replacement for QUEUE_FLAG_BYPASS isn't added
but the counter is tested directly. This will be further updated by
later changes.
* blk_mq_drain_queue() is dropped and "__" prefix is dropped from
blk_mq_freeze_queue(). Queue cleanup path now calls
blk_mq_freeze_queue() directly.
* blk_queue_enter()'s fast path condition is simplified to simply
check @q->mq_freeze_depth. Previously, the condition was
!blk_queue_dying(q) &&
(!blk_queue_bypass(q) || !blk_queue_init_done(q))
mq_freeze_depth is incremented right after dying is set and
blk_queue_init_done() exception isn't necessary as blk-mq doesn't
start frozen, which only leaves the blk_queue_bypass() test which
can be replaced by @q->mq_freeze_depth test.
This change simplifies the code and reduces confusion in the area.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Nicholas A. Bellinger <nab@linux-iscsi.org>
Signed-off-by: Jens Axboe <axboe@fb.com>
Currently, both blk_queue_bypass_start() and blk_mq_freeze_queue()
skip queue draining if bypass_depth was already above zero. The
assumption is that the one which bumped the bypass_depth should have
performed draining already; however, there's nothing which prevents a
new instance of bypassing/freezing from starting before the previous
one finishes draining. The current code may allow the later
bypassing/freezing instances to complete while there still are
in-flight requests which haven't finished draining.
Fix it by draining regardless of bypass_depth. We still skip draining
from blk_queue_bypass_start() while the queue is initializing to avoid
introducing excessive delays during boot. INIT_DONE setting is moved
above the initial blk_queue_bypass_end() so that bypassing attempts
can't slip inbetween.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Nicholas A. Bellinger <nab@linux-iscsi.org>
Signed-off-by: Jens Axboe <axboe@fb.com>
blk-mq uses a percpu_counter to keep track of how many usages are in
flight. The percpu_counter is drained while freezing to ensure that
no usage is left in-flight after freezing is complete.
blk_mq_queue_enter/exit() and blk_mq_[un]freeze_queue() implement this
per-cpu gating mechanism; unfortunately, it contains a subtle bug -
smp_wmb() in blk_mq_queue_enter() doesn't prevent prevent the cpu from
fetching @q->bypass_depth before incrementing @q->mq_usage_counter and
if freezing happens inbetween the caller can slip through and freezing
can be complete while there are active users.
Use smp_mb() instead so that bypass_depth and mq_usage_counter
modifications and tests are properly interlocked.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Nicholas A. Bellinger <nab@linux-iscsi.org>
Signed-off-by: Jens Axboe <axboe@fb.com>
Pull ARM fixes from Russell King:
"Another round of ARM fixes. The largest change here is the L2 changes
to work around problems for the Armada 37x/380 devices, where most of
the size comes down to comments rather than code.
The other significant fix here is for the ptrace code, to ensure that
rewritten syscalls work as intended. This was pointed out by Kees
Cook, but Will Deacon reworked the patch to be more elegant.
The remainder are fairly trivial changes"
* 'fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm:
ARM: 8087/1: ptrace: reload syscall number after secure_computing() check
ARM: 8086/1: Set memblock limit for nommu
ARM: 8085/1: sa1100: collie: add top boot mtd partition
ARM: 8084/1: sa1100: collie: revert back to cfi_probe
ARM: 8080/1: mcpm.h: remove unused variable declaration
ARM: 8076/1: mm: add support for HW coherent systems in PL310 cache
Note that I don't maintain Documentation/ABI/,
Documentation/devicetree/, or the language translation files.
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
These days most people use git to send patches so I have added a section
about that.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
On the syscall tracing path, we call out to secure_computing() to allow
seccomp to check the syscall number being attempted. As part of this, a
SIGTRAP may be sent to the tracer and the syscall could be re-written by
a subsequent SET_SYSCALL ptrace request. Unfortunately, this new syscall
is ignored by the current code unless TIF_SYSCALL_TRACE is also set on
the current thread.
This patch slightly reworks the enter path of the syscall tracing code
so that we always reload the syscall number from
current_thread_info()->syscall after the potential ptrace traps.
Acked-by: Kees Cook <keescook@chromium.org>
Tested-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Commit 1c2f87c (ARM: 8025/1: Get rid of meminfo) changed find_limits
to use memblock_get_current_limit for calculating the max_low pfn.
nommu targets never actually set a limit on memblock though which
means memblock_get_current_limit will just return the default
value. Set the memblock_limit to be the end of DDR to make sure
bounds are calculated correctly.
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The CFI mapping is now perfect so we can expose the top block, read only.
There isn't much to read, though, just the sharpsl_params values.
Signed-off-by: Andrea Adami <andrea.adami@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Reverts commit d26b17edaf
ARM: sa1100: collie.c: fall back to jedec_probe flash detection
Unfortunately the detection was challenged on the defective unit used for tests:
one of the NOR chips did not respond to the CFI query.
Moreover that bad device needed extra delays on erase-suspend/resume cycles.
Tested personally on 3 different units and with feedback of two other users.
Signed-off-by: Andrea Adami <andrea.adami@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The sync_phys variable has been replaced by link time computation in
mcpm_head.S before the code was submitted upstream.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
When a PL310 cache is used on a system that provides hardware
coherency, the outer cache sync operation is useless, and can be
skipped. Moreover, on some systems, it is harmful as it causes
deadlocks between the Marvell coherency mechanism, the Marvell PCIe
controller and the Cortex-A9.
To avoid this, this commit introduces a new Device Tree property
'arm,io-coherent' for the L2 cache controller node, valid only for the
PL310 cache. It identifies the usage of the PL310 cache in an I/O
coherent configuration. Internally, it makes the driver disable the
outer cache sync operation.
Note that technically speaking, a fully coherent system wouldn't
require any of the other .outer_cache operations. However, in
practice, when booting secondary CPUs, these are not yet coherent, and
therefore a set of cache maintenance operations are necessary at this
point. This explains why we keep the other .outer_cache operations and
only ->sync is disabled.
While in theory any write to a PL310 register could cause the
deadlock, in practice, disabling ->sync is sufficient to workaround
the deadlock, since the other cache maintenance operations are only
used in very specific situations.
Contrary to previous versions of this patch, this new version does not
simply NULL-ify the ->sync member, because the l2c_init_data
structures are now 'const' and therefore cannot be modified, which is
a good thing. Therefore, this patch introduces a separate
l2c_init_data instance, called of_l2c310_coherent_data.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
A few driver specific fixes, the biggest one being a fix for the newly
added Qualcomm SPI controller driver to make it not use its internal
chip select due to hardware bugs, replacing it with GPIOs.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1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=Jdak
-----END PGP SIGNATURE-----
Merge tag 'spi-v3.16-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi
Pull spi fixes from Mark Brown:
"A few driver specific fixes, the biggest one being a fix for the newly
added Qualcomm SPI controller driver to make it not use its internal
chip select due to hardware bugs, replacing it with GPIOs"
* tag 'spi-v3.16-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi:
spi: qup: Remove chip select function
spi: qup: Fix order of spi_register_master
spi: sh-sci: fix use-after-free in sh_sci_spi_remove()
spi/pxa2xx: fix incorrect SW mode chipselect setting for BayTrail LPSS SPI
Several driver specific fixes here, the palmas fixes being especially
important for a range of boards - the recent updates to support new
devices have introduced several regressions.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1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=K0Hp
-----END PGP SIGNATURE-----
Merge tag 'regulator-v3.16-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator
Pull regulator fixes from Mark Brown:
"Several driver specific fixes here, the palmas fixes being especially
important for a range of boards - the recent updates to support new
devices have introduced several regressions"
* tag 'regulator-v3.16-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator:
regulator: tps65218: Correct the the config register for LDO1
regulator: tps65218: Add the missing of_node assignment in probe
regulator: palmas: fix typo in enable_reg calculation
regulator: bcm590xx: fix vbus name
regulator: palmas: Fix SMPS enable/disable/is_enabled
Pull SCSI target fixes from Nicholas Bellinger:
"Mostly minor fixes this time around. The highlights include:
- iscsi-target CHAP authentication fixes to enforce explicit key
values (Tejas Vaykole + rahul.rane)
- fix a long-standing OOPs in target-core when a alua configfs
attribute is accessed after port symlink has been removed.
(Sebastian Herbszt)
- fix a v3.10.y iscsi-target regression causing the login reject
status class/detail to be ignored (Christoph Vu-Brugier)
- fix a v3.10.y iscsi-target regression to avoid rejecting an
existing ITT during Data-Out when data-direction is wrong (Santosh
Kulkarni + Arshad Hussain)
- fix a iscsi-target related shutdown deadlock on UP kernels (Mikulas
Patocka)
- fix a v3.16-rc1 build issue with vhost-scsi + !CONFIG_NET (MST)"
* git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending:
iscsi-target: fix iscsit_del_np deadlock on unload
iovec: move memcpy_from/toiovecend to lib/iovec.c
iscsi-target: Avoid rejecting incorrect ITT for Data-Out
tcm_loop: Fix memory leak in tcm_loop_submission_work error path
iscsi-target: Explicily clear login response PDU in exception path
target: Fix left-over se_lun->lun_sep pointer OOPs
iscsi-target; Enforce 1024 byte maximum for CHAP_C key value
iscsi-target: Convert chap_server_compute_md5 to use kstrtoul
Now that explicit invocation of percpu_ref_exit() is necessary to free
the percpu counter, we can implement percpu_ref_reinit() which
reinitializes a released percpu_ref. This can be used implement
scalable gating switch which can be drained and then re-opened without
worrying about memory allocation failures.
percpu_ref_is_zero() is added to be used in a sanity check in
percpu_ref_exit(). As this function will be useful for other purposes
too, make it a public interface.
v2: Use smp_read_barrier_depends() instead of smp_load_acquire(). We
only need data dep barrier and smp_load_acquire() is stronger and
heavier on some archs. Spotted by Lai Jiangshan.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Kent Overstreet <kmo@daterainc.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Currently, a percpu_ref undoes percpu_ref_init() automatically by
freeing the allocated percpu area when the percpu_ref is killed.
While seemingly convenient, this has the following niggles.
* It's impossible to re-init a released reference counter without
going through re-allocation.
* In the similar vein, it's impossible to initialize a percpu_ref
count with static percpu variables.
* We need and have an explicit destructor anyway for failure paths -
percpu_ref_cancel_init().
This patch removes the automatic percpu counter freeing in
percpu_ref_kill_rcu() and repurposes percpu_ref_cancel_init() into a
generic destructor now named percpu_ref_exit(). percpu_ref_destroy()
is considered but it gets confusing with percpu_ref_kill() while
"exit" clearly indicates that it's the counterpart of
percpu_ref_init().
All percpu_ref_cancel_init() users are updated to invoke
percpu_ref_exit() instead and explicit percpu_ref_exit() calls are
added to the destruction path of all percpu_ref users.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Benjamin LaHaise <bcrl@kvack.org>
Cc: Kent Overstreet <kmo@daterainc.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Benjamin LaHaise <bcrl@kvack.org>
Cc: Nicholas A. Bellinger <nab@linux-iscsi.org>
Cc: Li Zefan <lizefan@huawei.com>
percpu_ref->pcpu_count is a percpu pointer with a status flag in its
lowest bit. As such, it always goes through arithmetic operations
which is very cumbersome to do on a pointer. It has to be first
casted to unsigned long and then back.
Let's just make the field unsigned long so that we can skip the first
casts. While at it, rename it to pcpu_counter_ptr to clarify that
it's a pointer value.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Kent Overstreet <kmo@daterainc.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
* All four percpu_ref_*() operations implemented in the header file
perform the same operation to determine whether the percpu_ref is
alive and extract the percpu pointer. Factor out the common logic
into __pcpu_ref_alive(). This doesn't change the generated code.
* There are a couple places in percpu-refcount.c which masks out
PCPU_REF_DEAD to obtain the percpu pointer. Factor it out into
pcpu_count_ptr().
* The above changes make the WARN_ON_ONCE() conditional at the top of
percpu_ref_kill_and_confirm() the only user of REF_STATUS(). Test
PCPU_REF_DEAD directly and remove REF_STATUS().
This patch doesn't introduce any functional change.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Kent Overstreet <kmo@daterainc.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
percpu-refcount currently reserves two lowest bits of its percpu
pointer to indicate its state; however, only one bit is used for
PCPU_REF_DEAD.
Simplify it by removing PCPU_STATUS_BITS/MASK and testing
PCPU_REF_DEAD directly. This also allows the compiler to choose a
more efficient instruction depending on the architecture.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Kent Overstreet <kmo@daterainc.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
ioctx_alloc() reaches inside percpu_ref and directly frees
->pcpu_count in its failure path, which is quite gross. percpu_ref
has been providing a proper interface to do this,
percpu_ref_cancel_init(), for quite some time now. Let's use that
instead.
This patch doesn't introduce any behavior changes.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Benjamin LaHaise <bcrl@kvack.org>
Cc: Kent Overstreet <kmo@daterainc.com>
On uniprocessor preemptible kernel, target core deadlocks on unload. The
following events happen:
* iscsit_del_np is called
* it calls send_sig(SIGINT, np->np_thread, 1);
* the scheduler switches to the np_thread
* the np_thread is woken up, it sees that kthread_should_stop() returns
false, so it doesn't terminate
* the np_thread clears signals with flush_signals(current); and goes back
to sleep in iscsit_accept_np
* the scheduler switches back to iscsit_del_np
* iscsit_del_np calls kthread_stop(np->np_thread);
* the np_thread is waiting in iscsit_accept_np and it doesn't respond to
kthread_stop
The deadlock could be resolved if the administrator sends SIGINT signal to
the np_thread with killall -INT iscsi_np
The reproducible deadlock was introduced in commit
db6077fd0b, but the thread-stopping code was
racy even before.
This patch fixes the problem. Using kthread_should_stop to stop the
np_thread is unreliable, so we test np_thread_state instead. If
np_thread_state equals ISCSI_NP_THREAD_SHUTDOWN, the thread exits.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
* Fix VT-d regression with handling multiple RMRR entries per
device
* Fix a small race that was left in the mmu_notifier handling in
the AMD IOMMUv2 driver
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.0.22 (GNU/Linux)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=ZWyp
-----END PGP SIGNATURE-----
Merge tag 'iommu-fixes-v3.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu
Pull IOMMU fixes from Joerg Roedel:
- fix VT-d regression with handling multiple RMRR entries per device
- fix a small race that was left in the mmu_notifier handling in the
AMD IOMMUv2 driver
* tag 'iommu-fixes-v3.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
iommu/amd: Fix small race between invalidate_range_end/start
iommu/vt-d: fix bug in handling multiple RMRRs for the same PCI device
Pull x86 fixes from Peter Anvin:
"A pile of fixes related to the VDSO, EFI and 32-bit badsys handling.
It turns out that removing the section headers from the VDSO breaks
gdb, so this puts back most of them. A very simple typo broke
rt_sigreturn on some versions of glibc, with obviously disastrous
results. The rest is pretty much fixes for the corresponding fallout.
The EFI fixes fixes an arithmetic overflow on 32-bit systems and
quiets some build warnings.
Finally, when invoking an invalid system call number on x86-32, we
bypass a bunch of handling, which can make the audit code oops"
* 'x86/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
efi-pstore: Fix an overflow on 32-bit builds
x86/vdso: Error out in vdso2c if DT_RELA is present
x86/vdso: Move DISABLE_BRANCH_PROFILING into the vdso makefile
x86_32, signal: Fix vdso rt_sigreturn
x86_32, entry: Do syscall exit work on badsys (CVE-2014-4508)
x86/vdso: Create .build-id links for unstripped vdso files
x86/vdso: Remove some redundant in-memory section headers
x86/vdso: Improve the fake section headers
x86/vdso2c: Use better macros for ELF bitness
x86/vdso: Discard the __bug_table section
efi: Fix compiler warnings (unused, const, type)
Pull MIPS fixes from Ralf Baechle:
"This is dominated by a large number of changes necessary for the MIPS
BPF code. code. Aside of that there are
- a fix for the MSC system controller support code.
- a Turbochannel fix.
- a recordmcount fix that's MIPS-specific.
- barrier fixes to smp-cps / pm-cps after unrelated changes elsewhere
in the kernel.
- revert support for MSA registers in the signal frames. The
reverted patch did modify the signal stack frame which of course is
inacceptable.
- fix math-emu build breakage with older compilers.
- some related cleanup.
- fix Lasat build error if CONFIG_CRC32 isn't set to y by the user"
* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (27 commits)
MIPS: Lasat: Fix build error if CRC32 is not enabled.
TC: Handle device_register() errors.
MIPS: MSC: Prevent out-of-bounds writes to MIPS SC ioremap'd region
MIPS: bpf: Fix stack space allocation for BPF memwords on MIPS64
MIPS: BPF: Use 32 or 64-bit load instruction to load an address to register
MIPS: bpf: Fix PKT_TYPE case for big-endian cores
MIPS: BPF: Prevent kernel fall over for >=32bit shifts
MIPS: bpf: Drop update_on_xread and always initialize the X register
MIPS: bpf: Fix is_range() semantics
MIPS: bpf: Use pr_debug instead of pr_warn for unhandled opcodes
MIPS: bpf: Fix return values for VLAN_TAG_PRESENT case
MIPS: bpf: Use correct mask for VLAN_TAG case
MIPS: bpf: Fix branch conditional for BPF_J{GT/GE} cases
MIPS: bpf: Add SEEN_SKB to flags when looking for the PKT_TYPE
MIPS: bpf: Use 'andi' instead of 'and' for the VLAN cases
MIPS: bpf: Return error code if the offset is a negative number
MIPS: bpf: Use the LO register to get division's quotient
MIPS: mm: uasm: Fix lh micro-assembler instruction
MIPS: uasm: Add SLT uasm instruction
MIPS: uasm: Add s3s1s2 instruction builder
...
Here is another lz4 bugfix for 3.16-rc3 that resolves a reported issue
with that compression algorithm.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2
iEYEABECAAYFAlOuGXoACgkQMUfUDdst+ym2ggCgyo0pzGL72nt2lT4QjriPhLAq
3nwAnjB4x3sezmwoqlkqfhKGuRon2lMw
=Tcxf
-----END PGP SIGNATURE-----
Merge tag 'compress-3.16-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull compress bugfix from Greg KH:
"Here is another lz4 bugfix for 3.16-rc3 that resolves a reported issue
with that compression algorithm"
* tag 'compress-3.16-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
lz4: fix another possible overrun
* Don't assume that 0 as a physical address is incorrect and fail the request.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1
iQEcBAABAgAGBQJTpJSbAAoJEFjIrFwIi8fJSDQH/3wm3iDUrW+yxxXofTG056v3
mO4Yl2xAuP5bTVIQWEGU/3hxkfuHF4fKdHYULbZGmVMDfmT7SfnkT67i2uCFu3y5
H7/GjZwbo5Oz6PCWrR+xAd2Xp3TuDhs24/wi7xFhWswgacZWEJzjC41jGqJEZbpB
iidyI3z7/LppJcJAxzeBjCuqj//zL26Bk2nOKNtZIdRX4G+bEpRVRDLDBo7wSUmN
BIZysIsQtid24GwiV3FsG5WQypdIFSDJRNlkIeUHOEpVd9QDuTZLU5xbtM0suwHy
mAjaNTg3uGUoUbTrvf/lNmaxg1546moj2z2gKWCYJ9aEI28kNxI/G/mJ4ml2hWQ=
=wH3p
-----END PGP SIGNATURE-----
Merge tag 'stable/for-linus-3.16-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb
Pull swiotlb bugfix from Konrad Rzeszutek Wilk:
"One bug-fix that had been in tree for quite some time. We had assumed
that the physical address zero was invalid and would fail it. But
that is not true and on some architectures it is not reserved and
valid. This fixes it"
* tag 'stable/for-linus-3.16-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb:
swiotlb: don't assume PA 0 is invalid
Here includes a few patchset for fixing mostly HD-audio issues in
addition to a patch assuring the compress API bytes alignment and a
fix for the die-hard existing race condition at USB-audio
disconnection. The volume looks big in Realtek HD-audio code, but
it's just a translation of the fixup tables, and the actual changes
are rather trivial.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.0.22 (GNU/Linux)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=iKT+
-----END PGP SIGNATURE-----
Merge tag 'sound-3.16-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound
Pull sound fixes from Takashi Iwai:
"Here includes a few patchset for fixing mostly HD-audio issues in
addition to a patch assuring the compress API bytes alignment and a
fix for the die-hard existing race condition at USB-audio
disconnection. The volume looks big in Realtek HD-audio code, but
it's just a translation of the fixup tables, and the actual changes
are rather trivial"
* tag 'sound-3.16-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
ALSA: hda - restore BCLK M/N values when resuming HSW/BDW display controller
ALSA: usb-audio: Fix races at disconnection and PCM closing
ALSA: hda - Adjust speaker HPF and add LED support for HP Spectre 13
ALSA: hda - Make the pin quirk tables use the SND_HDA_PIN_QUIRK macro
ALSA: hda - Make a SND_HDA_PIN_QUIRK macro
ALSA: hda - Add pin quirk for Dell XPS 15
ALSA: hda - hdmi: call overridden init on resume
ALSA: hda - Fix usage of "model" module parameter
ALSA: compress: fix the struct alignment to 4 bytes
Pull drm fixes from Dave Airlie:
"Exynos, i915 and msm fixes and one core fix.
exynos:
hdmi power off and mixer issues
msm:
iommu, build fixes,
i915:
regression races and warning fixes"
* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux: (22 commits)
drm/i915: vlv_prepare_pll is only needed in case of non DSI interfaces
drm: fix NULL pointer access by wrong ioctl
drm/exynos: enable vsync interrupt while waiting for vblank
drm/exynos: soft reset mixer before reconfigure after power-on
drm/exynos: allow multiple layer updates per vsync for mixer
drm/i915: Hold the table lock whilst walking the file's idr and counting the objects in debugfs
drm/i915: BDW: Adding Reserved PCI IDs.
drm/i915: Only mark the ctx as initialised after a SET_CONTEXT operation
drm/exynos: stop mixer before gating clocks during poweroff
drm/exynos: set power state variable after enabling clocks and power
drm/exynos: disable unused windows on apply
drm/exynos: Fix de-registration ordering
drm/exynos: change zero to NULL for sparse
drm/exynos: dpi: Fix NULL pointer dereference with legacy bindings
drm/exynos: hdmi: fix power order issue
drm/i915: default to having backlight if VBT not available
drm/i915: cache hw power well enabled state
drm/msm: fix IOMMU cleanup for -EPROBE_DEFER
drm/msm: use PAGE_ALIGNED instead of IS_ALIGNED(PAGE_SIZE)
drm/msm/hdmi: set hdp clock rate before prepare_enable
...
ERROR: "memcpy_fromiovecend" [drivers/vhost/vhost_scsi.ko] undefined!
commit 9f977ef7b6
vhost-scsi: Include prot_bytes into expected data transfer length
in target-pending makes drivers/vhost/scsi.c call memcpy_fromiovecend().
This function is not available when CONFIG_NET is not enabled.
socket.h already includes uio.h, so no callers need updating.
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
