Stop hand rolling _MMIO_TRANS2() and just use the real thing.
Note that this register isn't even used atm, hence why this
builds despite the _PIPE2() macro not actually existing.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220623130900.26078-8-ville.syrjala@linux.intel.com
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Replace the deprecated ida_simple_{get,remove} with ida_{alloc,free}.
Link: https://lore.kernel.org/r/20220616055052.4559-1-liubo03@inspur.com
Signed-off-by: Bo Liu <liubo03@inspur.com>
[sudeep.holla: Replace ida_alloc_min with ida_alloc as suggested by Cristian]
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
The use of 'extern' in function prototypes has been disrecommended in
the kernel coding style for several years now, remove them from all vfio
related files so contributors no longer need to decide between style and
consistency.
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/165471414407.203056.474032786990662279.stgit@omen
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Eliminate the PIPECONF RMWs from .comit_commit() so
that we can finally declare the whole vblank evade part
(and the noarm() part) of the pipe commit free of register
reads. Or at least I hope that's the last read...
Only the i9xx/ilk codepaths need this for now, but let's
add the same thing for hsw+ just in case we want to start
calling that during fastsets at some point (eg. to change
dithering settings/etc.).
Should open up the way to start experimenting with
different DSB usage approaches for pipe commits.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220413192607.27533-1-ville.syrjala@linux.intel.com
Reviewed-by: Uma Shankar <uma.shankar@intel.com>
For imported dma-buf objects we leave the object as cache_coherent = 0
across all platforms, which is reasonable given that have no clue what
the memory underneath is, and its not like the driver can ever manually
clflush the pages anyway (like with i915_gem_clflush_object) for such
objects. However on discrete we choose to treat cache_dirty = true as a
programmer error, leading to a warning. The simplest fix looks to be to
just change the ordering in cpu_write_needs_clflush to prevent ever
setting cache_dirty for dma-buf objects on discrete.
Fixes: d028a7690d ("drm/i915/dmabuf: Fix prime_mmap to work when using LMEM")
Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/5266
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Gwan-gyeong Mun <gwan-gyeong.mun@intel.com>
Reviewed-by: Gwan-gyeong Mun <gwan-gyeong.mun@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220622155919.355081-1-matthew.auld@intel.com
(cherry picked from commit 563aaf4a92)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Currently i915 disables d3cold for i915 pci dev.
This blocks D3 for i915 gfx pci upstream bridge (VSP).
Let's disable d3cold at gfx root port to make sure that
i915 gfx VSP can transition to D3 to save some power.
We don't need to disable/enable d3cold in rpm, s2idle
suspend/resume handlers. Disabling/Enabling d3cold at
gfx root port in probe/remove phase is sufficient.
Fixes: 1a085e2341 ("drm/i915: Disable D3Cold in s2idle and runtime pm")
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Anshuman Gupta <anshuman.gupta@intel.com>
Reviewed-by: Badal Nilawar <badal.nilawar@intel.com>
Acked-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220616122249.5007-1-anshuman.gupta@intel.com
(cherry picked from commit 138c2fca6f)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Max Staudt says:
====================
This is the can327 driver. It does a surprisingly good job at turning
ELM327 based OBD-II interfaces into cheap CAN interfaces for simple
homebrew projects.
Please see the included documentation for details and limitations:
Documentation/networking/device_drivers/can/can327.rst
====================
Link: https://lore.kernel.org/all/20220618195031.10975-1-max@enpas.org/
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This is the can327 driver. It does a surprisingly good job at turning
ELM327 based OBD-II interfaces into cheap CAN interfaces for simple
homebrew projects.
Please see the included documentation for details and limitations:
Documentation/networking/device_drivers/can/can327.rst
Link: https://lore.kernel.org/all/20220618195031.10975-1-max@enpas.org
Signed-off-by: Max Staudt <max@enpas.org>
Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
[mkl: minor coding style improvements]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Commit 71066545b4 ("driver core: Set fw_devlink.strict=1 by default")
enabled iommus and dmas dependency enforcement by default. On some
systems, this caused the console device's probe to get delayed until the
deferred_probe_timeout expires.
We need consoles to work as soon as possible, so mark the console device
node with FWNODE_FLAG_BEST_EFFORT so that fw_delink knows not to delay
the probe of the console device for suppliers without drivers. The
driver can then make the decision on where it can probe without those
suppliers or defer its probe.
Fixes: 71066545b4 ("driver core: Set fw_devlink.strict=1 by default")
Reported-by: Sascha Hauer <sha@pengutronix.de>
Reported-by: Peng Fan <peng.fan@nxp.com>
Tested-by: Peng Fan <peng.fan@nxp.com>
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20220623080344.783549-3-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When firmware sets the FWNODE_FLAG_BEST_EFFORT flag for a fwnode,
fw_devlink will do a best effort ordering for that device where it'll
only enforce the probe/suspend/resume ordering of that device with
suppliers that have drivers. The driver of that device can then decide
if it wants to defer probe or probe without the suppliers.
This will be useful for avoid probe delays of the console device that
were caused by commit 71066545b4 ("driver core: Set
fw_devlink.strict=1 by default").
Fixes: 71066545b4 ("driver core: Set fw_devlink.strict=1 by default")
Reported-by: Sascha Hauer <sha@pengutronix.de>
Reported-by: Peng Fan <peng.fan@nxp.com>
Tested-by: Peng Fan <peng.fan@nxp.com>
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20220623080344.783549-2-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In current kernfs design a single mutex, kernfs_open_file_mutex, protects
the list of kernfs_open_file instances corresponding to a sysfs attribute.
So even if different tasks are opening or closing different sysfs files
they can contend on osq_lock of this mutex. The contention is more apparent
in large scale systems with few hundred CPUs where most of the CPUs have
running tasks that are opening, accessing or closing sysfs files at any
point of time.
Using hashed mutexes in place of a single global mutex, can significantly
reduce contention around global mutex and hence can provide better
scalability. Moreover as these hashed mutexes are not part of kernfs_node
objects we will not see any singnificant change in memory utilization of
kernfs based file systems like sysfs, cgroupfs etc.
Modify interface introduced in previous patch to make use of hashed
mutexes. Use kernfs_node address as hashing key.
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Imran Khan <imran.f.khan@oracle.com>
Link: https://lore.kernel.org/r/20220615021059.862643-5-imran.f.khan@oracle.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This allows to change underlying mutex locking, without needing to change
the users of the lock. For example next patch modifies this interface to
use hashed mutexes in place of a single global kernfs_open_file_mutex.
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Imran Khan <imran.f.khan@oracle.com>
Link: https://lore.kernel.org/r/20220615021059.862643-4-imran.f.khan@oracle.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
At present kernfs_notify_list is implemented as a singly linked
list of kernfs_node(s), where last element points to itself and
value of ->attr.next tells if node is present on the list or not.
Both addition and deletion to list happen under kernfs_notify_lock.
Change kernfs_notify_list to llist so that addition to list can heppen
locklessly.
Suggested by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Imran Khan <imran.f.khan@oracle.com>
Link: https://lore.kernel.org/r/20220615021059.862643-3-imran.f.khan@oracle.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
After removal of kernfs_open_node->refcnt in the previous patch,
kernfs_open_node_lock can be removed as well by making ->attr.open
RCU protected. kernfs_put_open_node can delegate freeing to ->attr.open
to RCU and other readers of ->attr.open can do so under rcu_read_(un)lock.
Suggested by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Imran Khan <imran.f.khan@oracle.com>
Link: https://lore.kernel.org/r/20220615021059.862643-2-imran.f.khan@oracle.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since previous 'rc = -EINVAL;', rc value doesn't change, so not
necessary to re-assign it again.
Signed-off-by: Lin Feng <linf@wangsu.com>
Link: https://lore.kernel.org/r/20220617091746.206515-1-linf@wangsu.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We've been introducing new registers with a mix of "XEHP_"
(architecture) and "XEHPSDV_" (platform) prefixes. For consistency,
let's settle on "XEHP_" as the preferred form.
XEHPSDV_RP_STATE_CAP stays with its current name since that's truly a
platform-specific register and not something that applies to the Xe_HP
architecture as a whole.
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Caz Yokoyama <caz@caztech.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220624210328.308630-2-matthew.d.roper@intel.com
XEHPSDV_FLAT_CCS_BASE_ADDR, GEN8_L3_LRA_1_GPGPU, and MMCD_MISC_CTRL were
duplicated between i915_reg.h and intel_gt_regs.h. These are all GT
registers, so we should drop the copy from i915_reg.h.
XEHPSDV_TILE0_ADDR_RANGE was defined in i915_reg.h, but really belongs
in intel_gt_regs.h. Move it.
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220624210328.308630-1-matthew.d.roper@intel.com
In __driver_attach function, There are also AA deadlock problem,
like the commit b232b02bf3 ("driver core: fix deadlock in
__device_attach").
stack like commit b232b02bf3 ("driver core: fix deadlock in
__device_attach").
list below:
In __driver_attach function, The lock holding logic is as follows:
...
__driver_attach
if (driver_allows_async_probing(drv))
device_lock(dev) // get lock dev
async_schedule_dev(__driver_attach_async_helper, dev); // func
async_schedule_node
async_schedule_node_domain(func)
entry = kzalloc(sizeof(struct async_entry), GFP_ATOMIC);
/* when fail or work limit, sync to execute func, but
__driver_attach_async_helper will get lock dev as
will, which will lead to A-A deadlock. */
if (!entry || atomic_read(&entry_count) > MAX_WORK) {
func;
else
queue_work_node(node, system_unbound_wq, &entry->work)
device_unlock(dev)
As above show, when it is allowed to do async probes, because of
out of memory or work limit, async work is not be allowed, to do
sync execute instead. it will lead to A-A deadlock because of
__driver_attach_async_helper getting lock dev.
Reproduce:
and it can be reproduce by make the condition
(if (!entry || atomic_read(&entry_count) > MAX_WORK)) untenable, like
below:
[ 370.785650] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables
this message.
[ 370.787154] task:swapper/0 state:D stack: 0 pid: 1 ppid:
0 flags:0x00004000
[ 370.788865] Call Trace:
[ 370.789374] <TASK>
[ 370.789841] __schedule+0x482/0x1050
[ 370.790613] schedule+0x92/0x1a0
[ 370.791290] schedule_preempt_disabled+0x2c/0x50
[ 370.792256] __mutex_lock.isra.0+0x757/0xec0
[ 370.793158] __mutex_lock_slowpath+0x1f/0x30
[ 370.794079] mutex_lock+0x50/0x60
[ 370.794795] __device_driver_lock+0x2f/0x70
[ 370.795677] ? driver_probe_device+0xd0/0xd0
[ 370.796576] __driver_attach_async_helper+0x1d/0xd0
[ 370.797318] ? driver_probe_device+0xd0/0xd0
[ 370.797957] async_schedule_node_domain+0xa5/0xc0
[ 370.798652] async_schedule_node+0x19/0x30
[ 370.799243] __driver_attach+0x246/0x290
[ 370.799828] ? driver_allows_async_probing+0xa0/0xa0
[ 370.800548] bus_for_each_dev+0x9d/0x130
[ 370.801132] driver_attach+0x22/0x30
[ 370.801666] bus_add_driver+0x290/0x340
[ 370.802246] driver_register+0x88/0x140
[ 370.802817] ? virtio_scsi_init+0x116/0x116
[ 370.803425] scsi_register_driver+0x1a/0x30
[ 370.804057] init_sd+0x184/0x226
[ 370.804533] do_one_initcall+0x71/0x3a0
[ 370.805107] kernel_init_freeable+0x39a/0x43a
[ 370.805759] ? rest_init+0x150/0x150
[ 370.806283] kernel_init+0x26/0x230
[ 370.806799] ret_from_fork+0x1f/0x30
To fix the deadlock, move the async_schedule_dev outside device_lock,
as we can see, in async_schedule_node_domain, the parameter of
queue_work_node is system_unbound_wq, so it can accept concurrent
operations. which will also not change the code logic, and will
not lead to deadlock.
Fixes: ef0ff68351 ("driver core: Probe devices asynchronously instead of the driver")
Signed-off-by: Zhang Wensheng <zhangwensheng5@huawei.com>
Link: https://lore.kernel.org/r/20220622074327.497102-1-zhangwensheng5@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This was already defined at stable/sysfs-devices-system-cpu with
the same description, as pointed by get_abi.pl:
Warning: /sys/devices/system/cpu/cpuX/topology/core_id is defined 2 times: Documentation/ABI/stable/sysfs-devices-system-cpu:38 Documentation/ABI/testing/sysfs-devices-system-cpu:69
Remove the duplicated one.
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
Link: https://lore.kernel.org/r/1e92337c1ef74f5eb9e1c1871e20b858b490d269.1656235926.git.mchehab@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This adds missing documentation for VDUSE sysfs interface ABI
under Documentation/ABI/testing.
Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20220524115143.187-1-xieyongji@bytedance.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add plane color encoding information for color space conversion.
It's a preparation for adding support for mt8195 ovl_adaptor mdp_rdma
csc control.
Signed-off-by: Nancy.Lin <nancy.lin@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Tested-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Tested-by: Bo-Chen Chen <rex-bc.chen@mediatek.com>
Link: https://patchwork.kernel.org/project/linux-mediatek/patch/20220620091930.27797-10-nancy.lin@mediatek.com/
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>
When the devtmpfs fails to mount, a dangling pointer still remains in
global. Specifically, the err variable is passed by a pointer to the
devtmpfsd. When the devtmpfsd exits, it sets the error and completes the
setup_done. In this situation, the thread pointer is not set to null.
After the devtmpfsd exited, the devtmpfs can wakes up the destroyed
devtmpfsd thread by wake_up_process if a device change event comes.
Signed-off-by: Yangxi Xiang <xyangxi5@gmail.com>
Link: https://lore.kernel.org/r/20220627120409.11174-1-xyangxi5@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add merge async reset control in mtk_merge_stop. Async hw doesn't do self
reset on each sof signal(start of frame), so need to reset the async to
clear the hw status for the next merge start.
Signed-off-by: Nancy.Lin <nancy.lin@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Tested-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Tested-by: Bo-Chen Chen <rex-bc.chen@mediatek.com>
Link: https://patchwork.kernel.org/project/linux-mediatek/patch/20220620091930.27797-8-nancy.lin@mediatek.com/
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>
This reverts commit 77515ebaf0 as it
causes build problems in linux-next. It needs to be reintroduced in a
way that can allow the api to evolve and not require a "flag day" to
catch all users.
Link: https://lore.kernel.org/r/20220623160723.7a44b573@canb.auug.org.au
Cc: Duoming Zhou <duoming@zju.edu.cn>
Cc: Brian Norris <briannorris@chromium.org>
Cc: Johannes Berg <johannes@sipsolutions.net>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit a52ed4866d as it
causes build problems in linux-next. It needs to be reintroduced in a
way that can allow the api to evolve and not require a "flag day" to
catch all users.
Link: https://lore.kernel.org/r/20220623160723.7a44b573@canb.auug.org.au
Cc: Duoming Zhou <duoming@zju.edu.cn>
Cc: Brian Norris <briannorris@chromium.org>
Cc: Johannes Berg <johannes@sipsolutions.net>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 555dbf1a9a ("nfsd: Replace use of rwsem with errseq_t")
incidentally broke translation of -EINVAL to nfserr_notsupp.
The patch restores that.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Fixes: 555dbf1a9a ("nfsd: Replace use of rwsem with errseq_t")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Add merge start/stop API for cmdq support. The ovl_adaptor merges
are configured with each drm plane update. Need to enable/disable
merge with cmdq making sure all the settings taken effect in the
same vblank.
Signed-off-by: Nancy.Lin <nancy.lin@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Tested-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Tested-by: Bo-Chen Chen <rex-bc.chen@mediatek.com>
Link: https://patchwork.kernel.org/project/linux-mediatek/patch/20220620091930.27797-6-nancy.lin@mediatek.com/
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>
Add merge new advance config API. The original merge API is
mtk_ddp_comp_funcs function prototype. The API interface parameters
cannot be modified, so add a new config API for extension. This is
the preparation for ovl_adaptor merge control.
Signed-off-by: Nancy.Lin <nancy.lin@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Tested-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Tested-by: Bo-Chen Chen <rex-bc.chen@mediatek.com>
Link: https://patchwork.kernel.org/project/linux-mediatek/patch/20220620091930.27797-5-nancy.lin@mediatek.com/
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>
Add MDP_RDMA driver for MT8195. MDP_RDMA is the DMA engine of
the ovl_adaptor component.
Signed-off-by: Nancy.Lin <nancy.lin@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Tested-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Tested-by: Bo-Chen Chen <rex-bc.chen@mediatek.com>
Link: https://patchwork.kernel.org/project/linux-mediatek/patch/20220620091930.27797-4-nancy.lin@mediatek.com/
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>
The recent change to split reads into chunks has several problems:
1. If an SPI controller has no transfer size limit, max_chunk is
SIZE_MAX, and num_msgs becomes zero, causing no data to be read
into the buffer, and exposing the original contents of the buffer
to userspace,
2. If the requested read size is not a multiple of the maximum
transfer size, the last transfer reads too much data, overflowing
the buffer,
3. The loop logic differs from the write case.
Fix the above by:
1. Keeping track of the number of bytes that are still to be
transferred, instead of precalculating the number of messages and
keeping track of the number of bytes tranfered,
2. Calculating the transfer size of each individual message, taking
into account the number of bytes left,
3. Switching from a "while"-loop to a "do-while"-loop, and renaming
"msg_count" to "segment".
While at it, drop the superfluous cast from "unsigned int" to "unsigned
int", also from at25_ee_write(), where it was probably copied from.
Fixes: 0a35780c75 ("eeprom: at25: Split reads into chunks and cap write size")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/7ae260778d2c08986348ea48ce02ef148100e088.1655817534.git.geert+renesas@glider.be
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If an error occurs after a successful idr_alloc() call, the corresponding
resource must be released with idr_remove() as already done in the .remove
function.
Update the error handling path to add the missing idr_remove() call.
Fixes: ada8a8a13b ("mfd: Add realtek pcie card reader driver")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/e8dc41716cbf52fb37a12e70d8972848e69df6d6.1655271216.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When the target process is busy, incoming oneway transactions are
queued in the async_todo list. If the clients continue sending extra
oneway transactions while the target process is frozen, this queue can
become too large to accommodate new transactions. That's why binder
driver introduced ONEWAY_SPAM_DETECTION to detect this situation. It's
helpful to debug the async binder buffer exhausting issue, but the
issue itself isn't solved directly.
In real cases applications are designed to send oneway transactions
repeatedly, delivering updated inforamtion to the target process.
Typical examples are Wi-Fi signal strength and some real time sensor
data. Even if the apps might only care about the lastet information,
all outdated oneway transactions are still accumulated there until the
frozen process is thawed later. For this kind of situations, there's
no existing method to skip those outdated transactions and deliver the
latest one only.
This patch introduces a new transaction flag TF_UPDATE_TXN. To use it,
use apps can set this new flag along with TF_ONE_WAY. When such an
oneway transaction is to be queued into the async_todo list of a frozen
process, binder driver will check if any previous pending transactions
can be superseded by comparing their code, flags and target node. If
such an outdated pending transaction is found, the latest transaction
will supersede that outdated one. This effectively prevents the async
binder buffer running out and saves unnecessary binder read workloads.
Acked-by: Todd Kjos <tkjos@google.com>
Signed-off-by: Li Li <dualli@google.com>
Link: https://lore.kernel.org/r/20220526220018.3334775-2-dualli@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There is a pointer being initialized with a zero, use NULL instead.
Cleans up sparse warning:
drivers/misc/lkdtm/cfi.c💯27: warning: Using plain integer as NULL pointer
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Link: https://lore.kernel.org/r/20220612202708.2754270-1-colin.i.king@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
there is an unexpected word "the" in the comments that need to be dropped
file: drivers/misc/cxl/cxl.h
line: 1107
+/* check if the given pci_dev is on the the cxl vphb bus */
changed to
+/* check if the given pci_dev is on the cxl vphb bus */
Acked-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Jiang Jian <jiangjian@cdjrlc.com>
Link: https://lore.kernel.org/r/20220621125321.122280-1-jiangjian@cdjrlc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
there is an unexpected word "the" in the comments that need to be dropped
file: ./drivers/misc/sgi-xp/xpc_uv.c
line: 1601
* to put the the msg_slot back on the free list.
changed to
* to put the msg_slot back on the free list.
Signed-off-by: Jiang Jian <jiangjian@cdjrlc.com>
Link: https://lore.kernel.org/r/20220621124840.119875-1-jiangjian@cdjrlc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
