Pull tty fixes from Greg KH:
"Here are two tty/vt fixes:
- delete the netx-serial driver as the arch has been removed, no need
to keep the serial driver for it around either.
- vt console_lock fix to resolve a reported noisy warning at runtime
Both of these have been in linux-next with no reported issues"
* tag 'tty-5.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
vt: Grab console_lock around con_is_bound in show_bind
tty: serial: netx: Delete driver
Pull SPDX fixes from Greg KH:
"Here are some small SPDX fixes for 5.3-rc2 for things that came in
during the 5.3-rc1 merge window that we previously missed.
Only three small patches here:
- two uapi patches to resolve some SPDX tags that were not correct
- fix an invalid SPDX tag in the iomap Makefile file
All have been properly reviewed on the public mailing lists"
* tag 'spdx-5.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx:
iomap: fix Invalid License ID
treewide: remove SPDX "WITH Linux-syscall-note" from kernel-space headers again
treewide: add "WITH Linux-syscall-note" to SPDX tag of uapi headers
If gpiolib is disabled, we use the inline stubs from gpio/consumer.h
instead of regular definitions of GPIO API. The stubs for 'optional'
variants of gpiod_get routines return NULL in this case as if the
relevant GPIO wasn't found. This is correct so far.
Calling other (non-gpio_get) stubs from this header triggers a warning
because the GPIO descriptor couldn't have been requested. The warning
however is unconditional (WARN_ON(1)) and is emitted even if the passed
descriptor pointer is NULL.
We don't want to force the users of 'optional' gpio_get to check the
returned pointer before calling e.g. gpiod_set_value() so let's only
WARN on non-NULL descriptors.
Cc: stable@vger.kernel.org
Reported-by: Claus H. Stovgaard <cst@phaseone.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Pull scheduler fixes from Thomas Gleixner:
"Two fixes for the fair scheduling class:
- Prevent freeing memory which is accessible by concurrent readers
- Make the RCU annotations for numa groups consistent"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/fair: Use RCU accessors consistently for ->numa_group
sched/fair: Don't free p->numa_faults with concurrent readers
Pull locking fixes from Thomas Gleixner:
"A set of locking fixes:
- Address the fallout of the rwsem rework. Missing ACQUIREs and a
sanity check to prevent a use-after-free
- Add missing checks for unitialized mutexes when mutex debugging is
enabled.
- Remove the bogus code in the generic SMP variant of
arch_futex_atomic_op_inuser()
- Fixup the #ifdeffery in lockdep to prevent compile warnings"
* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
locking/mutex: Test for initialized mutex
locking/lockdep: Clean up #ifdef checks
locking/lockdep: Hide unused 'class' variable
locking/rwsem: Add ACQUIRE comments
tty/ldsem, locking/rwsem: Add missing ACQUIRE to read_failed sleep loop
lcoking/rwsem: Add missing ACQUIRE to read_slowpath sleep loop
locking/rwsem: Add missing ACQUIRE to read_slowpath exit when queue is empty
locking/rwsem: Don't call owner_on_cpu() on read-owner
futex: Cleanup generic SMP variant of arch_futex_atomic_op_inuser()
Pull Devicetree fixes from Rob Herring:
"The nvmem changes would typically go thru Greg's tree, but they were
missed in the merge window. [ Acked by Greg ]
Summary:
- Fix mismatches in $id values and actual filenames. Now checked by
tools.
- Convert nvmem binding to DT schema
- Fix a typo in of_property_read_bool() kerneldoc
- Remove some redundant description in al-fic interrupt-controller"
* tag 'devicetree-fixes-for-5.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux:
dt-bindings: Fix more $id value mismatches filenames
dt-bindings: nvmem: SID: Fix the examples node names
dt-bindings: nvmem: Add YAML schemas for the generic NVMEM bindings
of: Fix typo in kerneldoc
dt-bindings: interrupt-controller: al-fic: remove redundant binding
dt-bindings: clk: allwinner,sun4i-a10-ccu: Correct path in $id
Pull libnvdimm fixes from Dan Williams:
"A collection of locking and async operations fixes for v5.3-rc2. These
had been soaking in a branch targeting the merge window, but missed
due to a regression hunt. This fixed up version has otherwise been in
-next this past week with no reported issues.
In order to gain confidence in the locking changes the pull also
includes a debug / instrumentation patch to enable lockdep coverage
for libnvdimm subsystem operations that depend on the device_lock for
exclusion. As mentioned in the changelog it is a hack, but it works
and documents the locking expectations of the sub-system in a way that
others can use lockdep to verify. The driver core touches got an ack
from Greg.
Summary:
- Fix duplicate device_unregister() calls (multiple threads competing
to do unregister work when scheduling device removal from a sysfs
attribute of the self-same device).
- Fix badblocks registration order bug. Ensure region badblocks are
initialized in advance of namespace registration.
- Fix a deadlock between the bus lock and probe operations.
- Export device-core infrastructure to coordinate async operations
via the device ->dead state.
- Add device-core infrastructure to validate device_lock() usage with
lockdep"
* tag 'libnvdimm-fixes-5.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
driver-core, libnvdimm: Let device subsystems add local lockdep coverage
libnvdimm/bus: Fix wait_nvdimm_bus_probe_idle() ABBA deadlock
libnvdimm/bus: Stop holding nvdimm_bus_list_mutex over __nd_ioctl()
libnvdimm/bus: Prepare the nd_ioctl() path to be re-entrant
libnvdimm/region: Register badblocks before namespaces
libnvdimm/bus: Prevent duplicate device_unregister() calls
drivers/base: Introduce kill_device()
"Findfrom" is not a word. Replace the function synopsis by something
that makes sense.
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Pull SCSI fixes from James Bottomley:
"Nine fixes: The most important core one is the dma_max_mapping_size
fix that corrects the boot problem Gunter Roeck was having. A couple
of other driver only fixes are significant, like the cxgbi selector
support addition, the alua 2 second delay and the fdomain build fix"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: scsi_dh_alua: always use a 2 second delay before retrying RTPG
scsi: ibmvfc: fix WARN_ON during event pool release
scsi: fcoe: fix a typo
scsi: megaraid_sas: Make some functions static
scsi: megaraid_sas: fix panic on loading firmware crashdump
scsi: megaraid_sas: fix spelling mistake "megarid_sas" -> "megaraid_sas"
scsi: core: fix the dma_max_mapping_size call
scsi: fdomain: fix building pcmcia front-end
scsi: target: cxgbit: add support for IEEE_8021QAZ_APP_SEL_STREAM selector
Pull documentation fixes from Jonathan Corbet:
"This is mostly a set of follow-on fixes from Mauro fixing various
fallout from the massive RST conversion; a few other small fixes as
well"
* tag 'docs-5.3-1' of git://git.lwn.net/linux: (21 commits)
docs: phy: Drop duplicate 'be made'
doc:it_IT: translations in process/
docs/vm: transhuge: fix typo in madvise reference
doc:it_IT: rephrase statement
doc:it_IT: align translation to mainline
docs: load_config.py: ensure subdirs end with "/"
docs: virtual: add it to the documentation body
docs: remove extra conf.py files
docs: load_config.py: avoid needing a conf.py just due to LaTeX docs
scripts/sphinx-pre-install: seek for Noto CJK fonts for pdf output
scripts/sphinx-pre-install: cleanup Gentoo checks
scripts/sphinx-pre-install: fix latexmk dependencies
scripts/sphinx-pre-install: don't use LaTeX with CentOS 7
scripts/sphinx-pre-install: fix script for RHEL/CentOS
docs: conf.py: only use CJK if the font is available
docs: conf.py: add CJK package needed by translations
docs: pdf: add all Documentation/*/index.rst to PDF output
docs: fix broken doc references due to renames
docs: power: add it to to the main documentation index
docs: powerpc: convert docs to ReST and rename to *.rst
...
Pull block fixes from Jens Axboe:
- Several io_uring fixes/improvements:
- Blocking fix for O_DIRECT (me)
- Latter page slowness for registered buffers (me)
- Fix poll hang under certain conditions (me)
- Defer sequence check fix for wrapped rings (Zhengyuan)
- Mismatch in async inc/dec accounting (Zhengyuan)
- Memory ordering issue that could cause stall (Zhengyuan)
- Track sequential defer in bytes, not pages (Zhengyuan)
- NVMe pull request from Christoph
- Set of hang fixes for wbt (Josef)
- Redundant error message kill for libahci (Ding)
- Remove unused blk_mq_sched_started_request() and related ops (Marcos)
- drbd dynamic alloc shash descriptor to reduce stack use (Arnd)
- blkcg ->pd_stat() non-debug print (Tejun)
- bcache memory leak fix (Wei)
- Comment fix (Akinobu)
- BFQ perf regression fix (Paolo)
* tag 'for-linus-20190726' of git://git.kernel.dk/linux-block: (24 commits)
io_uring: ensure ->list is initialized for poll commands
Revert "nvme-pci: don't create a read hctx mapping without read queues"
nvme: fix multipath crash when ANA is deactivated
nvme: fix memory leak caused by incorrect subsystem free
nvme: ignore subnqn for ADATA SX6000LNP
drbd: dynamically allocate shash descriptor
block: blk-mq: Remove blk_mq_sched_started_request and started_request
bcache: fix possible memory leak in bch_cached_dev_run()
io_uring: track io length in async_list based on bytes
io_uring: don't use iov_iter_advance() for fixed buffers
block: properly handle IOCB_NOWAIT for async O_DIRECT IO
blk-mq: allow REQ_NOWAIT to return an error inline
io_uring: add a memory barrier before atomic_read
rq-qos: use a mb for got_token
rq-qos: set ourself TASK_UNINTERRUPTIBLE after we schedule
rq-qos: don't reset has_sleepers on spurious wakeups
rq-qos: fix missed wake-ups in rq_qos_throttle
wait: add wq_has_single_sleeper helper
block, bfq: check also in-flight I/O in dispatch plugging
block: fix sysfs module parameters directory path in comment
...
Pull sound fixes from Takashi Iwai:
"All relatively small changes:
- a regression fix for PCM link code with CONFIG_REFCOUNT_FULL;
stumbled on a slight difference between atomic_t and refcount_t
- a couple of HD-audio stabilization patches addressing the too slow
PM resume seen on some Intel chips
- a series of ALSA compress-offload API fixes, including the
regression by the previous capture stream support
- trivial LINE6 USB-audio driver fixes, a new Conexant HD-audio chip
coverage, and a fix in AC97 bus error path"
* tag 'sound-5.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
ALSA: hda - Add a conexant codec entry to let mute led work
ALSA: hda - Fix intermittent CORB/RIRB stall on Intel chips
ALSA: ac97: Fix double free of ac97_codec_device
ALSA: compress: Be more restrictive about when a drain is allowed
ALSA: compress: Don't allow paritial drain operations on capture streams
ALSA: compress: Prevent bypasses of set_params
ALSA: compress: Fix regression on compressed capture streams
ALSA: line6: Fix a typo
ALSA: pcm: Fix refcount_inc() on zero usage
ALSA: line6: Fix wrong altsetting for LINE6_PODHD500_1
ALSA: hda - Optimize resume for codecs without jack detection
Pull IOMMU fixes from Joerg Roedel:
- revert an Intel VT-d patch that caused boot problems on some machines
- fix AMD IOMMU interrupts with x2apic enabled
- fix a potential crash when Intel VT-d domain allocation fails
- fix crash in Intel VT-d driver when accessing a domain without a
flush queue
- formatting fix for new Intel VT-d debugfs code
- fix for use-after-free bug in IOVA code
- fix for a NULL-pointer dereference in Intel VT-d driver when PCI
hotplug is used
- compilation fix for one of the previous fixes
* tag 'iommu-fixes-v5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
iommu/amd: Add support for X2APIC IOMMU interrupts
iommu/iova: Fix compilation error with !CONFIG_IOMMU_IOVA
iommu/vt-d: Print pasid table entries MSB to LSB in debugfs
iommu/iova: Remove stale cached32_node
iommu/vt-d: Check if domain->pgd was allocated
iommu/vt-d: Don't queue_iova() if there is no flush queue
iommu/vt-d: Avoid duplicated pci dma alias consideration
Revert "iommu/vt-d: Consolidate domain_init() to avoid duplication"
All available downstream ports - physical and logical - are exposed for
each MST device. They are listed in /dev/, following the same naming
scheme as SST devices by appending an incremental ID.
Although all downstream ports are exposed, only some will work as
expected. Consider the following topology:
+---------+
| ASIC |
+---------+
Conn-0|
|
+----v----+
+----| MST HUB |----+
| +---------+ |
| |
|Port-1 Port-2|
+-----v-----+ +-----v-----+
| MST | | SST |
| Display | | Display |
+-----------+ +-----------+
|Port-1
x
MST Path | MST Device
----------+----------------------------------
sst:0 | MST Hub
mst:0-1 | MST Display
mst:0-1-1 | MST Display's disconnected DP out
mst:0-1-8 | MST Display's internal sink
mst:0-2 | SST Display
On certain MST displays, the upstream physical port will ACK DPCD reads.
However, reads on the local logical port to the internal sink will
*NAK*. i.e. reading mst:0-1 ACKs, but mst:0-1-8 NAKs.
There may also be duplicates. Some displays will return the same GUID
when reading DPCD from both mst:0-1 and mst:0-1-8.
There are some device-dependent behavior as well. The MST hub used
during testing will actually *ACK* read requests on a disconnected
physical port, whereas the MST displays will NAK.
In light of these discrepancies, it's simpler to expose all downstream
ports - both physical and logical - and let the user decide what to use.
v3 changes:
* Change WARN_ON_ONCE -> DRM_ERROR on dpcd read errors
* Docstring and cosmetic fixes
v2 changes:
Moved remote aux device (un)registration to new mst connector late
register and early unregister helpers. Drivers should call these from
their own mst connector function hooks.
This is to solve an issue during driver unload, where mst connector
devices are unregistered before the remote aux devices are. In a setup
where aux devices are created as children of connector devices, the aux
device would be removed too early, and uncleanly. Doing so in
early_unregister solves this issue, as that is called before connector
unregistration.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Leo Li <sunpeng.li@amd.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Harry Wentland <harry.wentland@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190723232808.28128-3-sunpeng.li@amd.com
These two functions are marked as a legacy APIs to get rid of, but seem to
suit the current nouveau flow. Move it to the only user in preparation
for fixing a locking bug involving caller and callee. All comments
referring to the old API have been removed as this now is a driver private
helper.
Link: https://lore.kernel.org/r/20190724065258.16603-3-hch@lst.de
Tested-by: Ralph Campbell <rcampbell@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Add a description for the context parameter in the struct wmi_device_id.
Reported-by: kbuild test robot <lkp@intel.com>
Fixes: a48e23385f ("platform/x86: wmi: add context pointer field to struct wmi_device_id")
Signed-off-by: Mattias Jacobsson <2pi@mok.nu>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
The access() (and faccessat()) credentials change can cause an
unnecessary load on the RCU machinery because every access() call ends
up freeing the temporary access credential using RCU.
This isn't really noticeable on small machines, but if you have hundreds
of cores you can cause huge slowdowns due to RCU storms.
It's easy to avoid: the temporary access crededntials aren't actually
normally accessed using RCU at all, so we can avoid the whole issue by
just marking them as such.
* access-creds:
access: avoid the RCU grace period for the temporary subjective credentials
When going through execve(), zero out the NUMA fault statistics instead of
freeing them.
During execve, the task is reachable through procfs and the scheduler. A
concurrent /proc/*/sched reader can read data from a freed ->numa_faults
allocation (confirmed by KASAN) and write it back to userspace.
I believe that it would also be possible for a use-after-free read to occur
through a race between a NUMA fault and execve(): task_numa_fault() can
lead to task_numa_compare(), which invokes task_weight() on the currently
running task of a different CPU.
Another way to fix this would be to make ->numa_faults RCU-managed or add
extra locking, but it seems easier to wipe the NUMA fault statistics on
execve.
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will@kernel.org>
Fixes: 82727018b0 ("sched/numa: Call task_numa_free() from do_execve()")
Link: https://lkml.kernel.org/r/20190716152047.14424-1-jannh@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The "WITH Linux-syscall-note" exception exists for headers exported to
user space. It is strange to add it to non-exported headers.
Commit 687a3e4d8e ("treewide: remove SPDX "WITH Linux-syscall-note"
from kernel-space headers") did cleanups some months ago, but it looks
like we need to do this periodically.
This patch was generated by the following script:
git grep -l -e Linux-syscall-note \
-- :*.h :^arch/*/include/uapi/asm/*.h :^include/uapi/ :^tools |
while read file
do
sed -i -e 's/(\(GPL-[^[:space:]]*\) WITH Linux-syscall-note)/\1/g' \
-e 's/ WITH Linux-syscall-note//g' $file
done
I did not commit drivers/staging/android/uapi/ion.h . This header is
not currently exported, but somebody may plan to move it to include/uapi/
when the time comes. I am not sure. Anyway, it will be better to check
the license inconsistency in drivers/staging/android/uapi/.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
UAPI headers licensed under GPL are supposed to have exception
"WITH Linux-syscall-note" so that they can be included into non-GPL
user space application code.
The exception note is missing in some UAPI headers.
Some of them slipped in by the treewide conversion commit b24413180f
("License cleanup: add SPDX GPL-2.0 license identifier to files with
no license"). Just run:
$ git show --oneline b24413180f -- arch/x86/include/uapi/asm/
I believe they are not intentional, and should be fixed too.
This patch was generated by the following script:
git grep -l --not -e Linux-syscall-note --and -e SPDX-License-Identifier \
-- :arch/*/include/uapi/asm/*.h :include/uapi/ :^*/Kbuild |
while read file
do
sed -i -e '/[[:space:]]OR[[:space:]]/s/\(GPL-[^[:space:]]*\)/(\1 WITH Linux-syscall-note)/g' \
-e '/[[:space:]]or[[:space:]]/s/\(GPL-[^[:space:]]*\)/(\1 WITH Linux-syscall-note)/g' \
-e '/[[:space:]]OR[[:space:]]/!{/[[:space:]]or[[:space:]]/!s/\(GPL-[^[:space:]]*\)/\1 WITH Linux-syscall-note/g}' $file
done
After this patch is applied, there are 5 UAPI headers that do not contain
"WITH Linux-syscall-note". They are kept untouched since this exception
applies only to GPL variants.
$ git grep --not -e Linux-syscall-note --and -e SPDX-License-Identifier \
-- :arch/*/include/uapi/asm/*.h :include/uapi/ :^*/Kbuild
include/uapi/drm/panfrost_drm.h:/* SPDX-License-Identifier: MIT */
include/uapi/linux/batman_adv.h:/* SPDX-License-Identifier: MIT */
include/uapi/linux/qemu_fw_cfg.h:/* SPDX-License-Identifier: BSD-3-Clause */
include/uapi/linux/vbox_err.h:/* SPDX-License-Identifier: MIT */
include/uapi/linux/virtio_iommu.h:/* SPDX-License-Identifier: BSD-3-Clause */
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Split struct mipi_dbi into an interface part and a display pipeline part.
The interface part can be used by drivers that need to initialize the
controller, but that won't upload the framebuffer over this interface.
MIPI DBI supports 3 interface types:
- A. Motorola 6800 type parallel bus
- B. Intel 8080 type parallel bus
- C. SPI type with 3 options:
I've embedded the SPI type specifics in the mipi_dbi struct to avoid
adding unnecessary complexity. If more interface types will be supported
in the future, the type specifics might have to be split out.
Rename functions to match the new struct mipi_dbi_dev:
- drm_to_mipi_dbi() -> drm_to_mipi_dbi_dev().
- mipi_dbi_init*() -> mipi_dbi_dev_init*().
Cc: Eric Anholt <eric@anholt.net>
Cc: David Lechner <david@lechnology.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Acked-by: David Lechner <david@lechnology.com>
Acked-by: Eric Anholt <eric@anholt.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20190722104312.16184-5-noralf@tronnes.org
struct mipi_dbi is going to be split into an interface part and a display
pipeline part. The interface part can be used by drivers that need to
initialize the controller, but that won't upload the framebuffer over
this interface.
tinydrm uses the variable name 'mipi' but this is not a good name since
MIPI refers to a lot of standards. This patch changes the variable name
to 'dbidev' where it refers to the pipeline part of struct mipi_dbi.
Cc: Eric Anholt <eric@anholt.net>
Cc: David Lechner <david@lechnology.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Acked-by: David Lechner <david@lechnology.com>
Acked-by: Eric Anholt <eric@anholt.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20190722104312.16184-4-noralf@tronnes.org
struct mipi_dbi is going to be split into an interface part and a display
pipeline part. The interface part can be used by drivers that need to
initialize the controller, but that won't upload the framebuffer over
this interface.
tinydrm uses the variable name 'mipi' but this is not a good name since
MIPI refers to a lot of standards. This patch changes the variable name
to 'dbi' where it refers to the interface part of struct mipi_dbi.
Functions that use both future parts will have both variables temporarily
pointing to the same structure.
Cc: Eric Anholt <eric@anholt.net>
Cc: David Lechner <david@lechnology.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Acked-by: David Lechner <david@lechnology.com>
Acked-by: Eric Anholt <eric@anholt.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20190722104312.16184-3-noralf@tronnes.org
It turns out that 'access()' (and 'faccessat()') can cause a lot of RCU
work because it installs a temporary credential that gets allocated and
freed for each system call.
The allocation and freeing overhead is mostly benign, but because
credentials can be accessed under the RCU read lock, the freeing
involves a RCU grace period.
Which is not a huge deal normally, but if you have a lot of access()
calls, this causes a fair amount of seconday damage: instead of having a
nice alloc/free patterns that hits in hot per-CPU slab caches, you have
all those delayed free's, and on big machines with hundreds of cores,
the RCU overhead can end up being enormous.
But it turns out that all of this is entirely unnecessary. Exactly
because access() only installs the credential as the thread-local
subjective credential, the temporary cred pointer doesn't actually need
to be RCU free'd at all. Once we're done using it, we can just free it
synchronously and avoid all the RCU overhead.
So add a 'non_rcu' flag to 'struct cred', which can be set by users that
know they only use it in non-RCU context (there are other potential
users for this). We can make it a union with the rcu freeing list head
that we need for the RCU case, so this doesn't need any extra storage.
Note that this also makes 'get_current_cred()' clear the new non_rcu
flag, in case we have filesystems that take a long-term reference to the
cred and then expect the RCU delayed freeing afterwards. It's not
entirely clear that this is required, but it makes for clear semantics:
the subjective cred remains non-RCU as long as you only access it
synchronously using the thread-local accessors, but you _can_ use it as
a generic cred if you want to.
It is possible that we should just remove the whole RCU markings for
->cred entirely. Only ->real_cred is really supposed to be accessed
through RCU, and the long-term cred copies that nfs uses might want to
explicitly re-enable RCU freeing if required, rather than have
get_current_cred() do it implicitly.
But this is a "minimal semantic changes" change for the immediate
problem.
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Eric Dumazet <edumazet@google.com>
Acked-by: Paul E. McKenney <paulmck@linux.ibm.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Jan Glauber <jglauber@marvell.com>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Jayachandran Chandrasekharan Nair <jnair@marvell.com>
Cc: Greg KH <greg@kroah.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull KVM fixes from Paolo Bonzini:
"Bugfixes, a pvspinlock optimization, and documentation moving"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: X86: Boost queue head vCPU to mitigate lock waiter preemption
Documentation: move Documentation/virtual to Documentation/virt
KVM: nVMX: Set cached_vmcs12 and cached_shadow_vmcs12 NULL after free
KVM: X86: Dynamically allocate user_fpu
KVM: X86: Fix fpu state crash in kvm guest
Revert "kvm: x86: Use task structs fpu field for user"
KVM: nVMX: Clear pending KVM_REQ_GET_VMCS12_PAGES when leaving nested
Renaming docs seems to be en vogue at the moment, so fix on of the
grossly misnamed directories. We usually never use "virtual" as
a shortcut for virtualization in the kernel, but always virt,
as seen in the virt/ top-level directory. Fix up the documentation
to match that.
Fixes: ed16648eb5 ("Move kvm, uml, and lguest subdirectories under a common "virtual" directory, I.E:")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
#define relative to FCOE CTLR start with FCOE_CTLR, except
FCOE_CTRL_SOL_TOV.
This is likely a typo and CTRL should be CTLR here as well.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
We currently have cases where the dma_addressing_limited() gets
called with dma_mask unset. This causes a NULL pointer dereference.
Use dma_get_mask() accessor to prevent the crash.
Fixes: b866455423 ("dma-mapping: add a dma_addressing_limited helper")
Signed-off-by: Eric Auger <eric.auger@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
The MIPI DBI standard support more pixel formats than what this helper
supports. Add an init function that lets the driver use different
format(s). This avoids open coding mipi_dbi_init() in st7586.
st7586 sets preferred_depth but this is not necessary since it only
supports one format.
v2: Forgot to remove the mipi->rotation assignment in st7586,
mipi_dbi_init_with_formats() handles it.
Cc: David Lechner <david@lechnology.com>
Acked-by: David Lechner <david@lechnology.com>
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Tested-by: David Lechner <david@lechnology.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190719155916.62465-11-noralf@tronnes.org
This is only used by mipi-dbi drivers so move it there.
The reason this isn't moved to the SPI subsystem is that it will in a
later patch pass a dummy rx buffer for SPI controllers that need this.
Low memory boards (64MB) can run into a problem allocating such a "large"
contiguous buffer on every transfer after a long up time.
This leaves a very specific use case, so we'll keep the function here.
mipi-dbi will first go through a refactoring though, before this will
be done.
Remove SPI todo entry now that we're done with the tinydrm.ko SPI code.
v2: Drop moving the mipi_dbi_spi_init() declaration (Sam)
Cc: David Lechner <david@lechnology.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: : David Lechner <david@lechnology.com>
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190719155916.62465-8-noralf@tronnes.org
Prep work before moving the function to mipi-dbi.
tinydrm_spi_transfer() was made to support one class of drivers in
drivers/staging/fbtft that has not been converted to DRM yet, so strip
away the unused functionality:
- Start byte (header) is not used.
- No driver relies on the automatic 16-bit byte swapping on little endian
machines with SPI controllers only supporting 8 bits per word.
Other changes:
- No need to initialize ret
- No need for the WARN since mipi-dbi only uses 8 and 16 bpw.
- Use spi_message_init_with_transfers()
Cc: David Lechner <david@lechnology.com>
Acked-by: : David Lechner <david@lechnology.com>
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190719155916.62465-7-noralf@tronnes.org
spi-bcm2835 can handle >64kB buffers now so there is no need to check
->max_dma_len. The tinydrm_spi_max_transfer_size() max_len argument is
not used by any callers, so not needed.
Then we have the spi_max module parameter. It was added because
staging/fbtft has support for it and there was a report that someone used
it to set a small buffer size to avoid popping on a USB soundcard on a
Raspberry Pi. In hindsight it shouldn't have been added, I should have
waited for it to become a problem first. I don't know it anyone is
actually using it, but since tinydrm_spi_transfer() is being moved to
mipi-dbi, I'm taking the opportunity to remove it. I'll add it back to
mipi-dbi if someone complains.
With that out of the way, spi_max_transfer_size() can be used instead.
The chosen 16kB buffer size for Type C Option 1 (9-bit) interface is
somewhat arbitrary, but a bigger buffer will have a miniscule impact on
transfer speed, so it's probably fine.
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190719155916.62465-6-noralf@tronnes.org
tinydrm drivers announce DRM_MODE_CONNECTOR_VIRTUAL for its SPI drivers.
Add a SPI connector type to match the actual connector.
X will list the connector as Unknown:
X.Org X Server 1.19.2
Release Date: 2017-03-02
<...>
[ 53523.905] (II) modeset(0): Output Unknown19-1 has no monitor section
[ 53523.908] (II) modeset(0): EDID for output Unknown19-1
[ 53523.910] (II) modeset(0): Printing probed modes for output Unknown19-1
[ 53523.911] (II) modeset(0): Modeline "320x240"x0.0 0.00 320 320 320 320 240 240 240 240 (0.0 kHz eP)
[ 53523.911] (II) modeset(0): Output Unknown19-1 connected
[ 53523.912] (II) modeset(0): Using exact sizes for initial modes
[ 53523.912] (II) modeset(0): Output Unknown19-1 using initial mode 320x240 +0+0
The weston source shows that it will be listed as UNNAMED.
v2: Split patch in core and driver changes, expand commit message (Daniel)
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: David Lechner <david@lechnology.com>
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190719155916.62465-2-noralf@tronnes.org
blk_mq_sched_completed_request is a function that checks if the elevator
related to the request has started_request implemented, but currently, none of
the available IO schedulers implement started_request, so remove both.
Signed-off-by: Marcos Paulo de Souza <marcos.souza.org@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
A previous fix to the stop handling on compressed capture streams causes
some knock on issues. The previous fix updated snd_compr_drain_notify to
set the state back to PREPARED for capture streams. This causes some
issues however as the handling for snd_compr_poll differs between the
two states and some user-space applications were relying on the poll
failing after the stream had been stopped.
To correct this regression whilst still fixing the original problem the
patch was addressing, update the capture handling to skip the PREPARED
state rather than skipping the SETUP state as it has done until now.
Fixes: 4f2ab5e1d1 ("ALSA: compress: Fix stop handling on compressed capture streams")
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Acked-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
The stub function for !CONFIG_IOMMU_IOVA needs to be
'static inline'.
Fixes: effa467870 ('iommu/vt-d: Don't queue_iova() if there is no flush queue')
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Fix an incomplete devm_clk_bulk_get_optional() function documentation
by adding description of the num_clks argument as in other *clk_bulk*
functions.
Fixes: 9bd5ef0bd8 ("clk: Add devm_clk_bulk_get_optional() function")
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
