The 'max' argument of ida_alloc_max() takes the maximum valid ID and not
the "count". Using an ID of BINDERFS_MAX_MINOR (1 << 20) for dev->minor
would exceed the limits of minor numbers (20-bits). Fix this off-by-one
error by subtracting 1 from the 'max'.
Cc: stable@vger.kernel.org
Fixes: eafedbc7c0 ("rust_binder: add Rust Binder driver")
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/r/202512181203.IOv6IChH-lkp@intel.com/
Signed-off-by: Carlos Llamas <cmllamas@google.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://patch.msgid.link/20260127235545.2307876-1-cmllamas@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Update call sites in binder files to import `ARef`
from `sync::aref` instead of `types`.
This aligns with the ongoing effort to move `ARef` and
`AlwaysRefCounted` to sync.
Suggested-by: Benno Lossin <lossin@kernel.org>
Link: https://github.com/Rust-for-Linux/linux/issues/1173
Signed-off-by: Shankari Anand <shankari.ak0208@gmail.com>
Acked-by: Alice Ryhl <aliceryhl@google.com>
Link: https://patch.msgid.link/20260102202714.184223-2-shankari.ak0208@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Clippy warns about a needless borrow in context.rs:
error: this expression creates a reference which is immediately dereferenced by the compiler
--> drivers/android/binder/context.rs:141:18
|
141 | func(&proc);
| ^^^^^ help: change this to: `proc`
Remove the unnecessary borrow to satisfy clippy and improve code
cleanliness. No functional change.
Signed-off-by: Shivam Kalra <shivamklr@cock.li>
Acked-by: Alice Ryhl <aliceryhl@google.com>
Link: https://patch.msgid.link/20260130182842.217821-1-shivamklr@cock.li
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently, if the command line passed to kexec_file_load() exceeds
the supported limit of the kernel being kexec'd, -EINVAL is returned
to userspace, which is consistent across architectures. Since
-EINVAL is not specific to this case, the kexec tool cannot provide
a specific reason for the failure. Many architectures emit an error
message in this case. Add a similar error message, including the
effective limit, since the command line length is configurable.
Acked-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Enable BLK_DEV_NULL_BLK as module in defconfig and debug_defconfig, so the
Null Test Block Device Driver can be easily used for testing purposes.
Signed-off-by: Halil Pasic <pasic@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Heiner Kallweit says:
====================
net: phy: remove modalias-based MDIO device bus matching
modalias-based MDIO device bus matching has only one user (dsa-loop),
where we can replace modalias-based matching with a simple custom
match function. This, and first patch of the series, lay the foundation
for removing modalias-based matching.
====================
Link: https://patch.msgid.link/d9543e7d-23e1-4dba-a6b3-35dcd6a35dec@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Last user dsa_loop has been migrated away from modalias-based matching,
so we can remove this feature now. It was the only user of MDIO_NAME_SIZE,
so remove also this constant.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Link: https://patch.msgid.link/ce1c6df0-4785-4b28-8322-32dc6bceea18@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
This change is a prerequisite for removing the MDIO device modalias,
as dsa_loop is the only user. Switch from modalias to a custom
bus match function.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Tested-by: Vladimir Oltean <olteanv@gmail.com>
Link: https://patch.msgid.link/15a4318f-50b5-4df5-874e-e387ee070a9d@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Primary reason for this change is to remove the misuse of MDIO_NAME_SIZE
here, so that this constant can be removed in a follow-up patch.
Use case here is simply a chip name w/o any relationship to a MDIO
device. Also there's no need to reserve a longer char array, so make
the name a pointer.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Link: https://patch.msgid.link/61bc14fa-eed3-43b6-ae40-b98063e81578@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
According to the include/drm/drm_bridge.h, the callback
&drm_bridge_funcs.mode_set is deprecated and it should be better to
include the mode setting in the &drm_bridge_funcs.atomic_enable instead.
Signed-off-by: Damon Ding <damon.ding@rock-chips.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Tested-by: Heiko Stuebner <heiko@sntech.de> (on rk3588)
Link: https://patch.msgid.link/20251217093321.3108939-4-damon.ding@rock-chips.com
Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Use the tap instead of the space for &analogix_dp_device.aux and
&analogix_dp_device.force_hpd.
Signed-off-by: Damon Ding <damon.ding@rock-chips.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Tested-by: Heiko Stuebner <heiko@sntech.de> (on rk3588)
Link: https://patch.msgid.link/20251217093321.3108939-3-damon.ding@rock-chips.com
Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
When multiple bridges are present, EDID detection capability
(DRM_BRIDGE_OP_EDID) takes precedence over modes detection
(DRM_BRIDGE_OP_MODES). To ensure the above two capabilities are
determined by the last bridge in the chain, we handle three cases:
Case 1: The later bridge declares only DRM_BRIDGE_OP_MODES
- If the previous bridge declares DRM_BRIDGE_OP_EDID, set
&drm_bridge_connector.bridge_edid to NULL and set
&drm_bridge_connector.bridge_modes to the later bridge.
- Ensure modes detection capability of the later bridge will not
be ignored.
Case 2: The later bridge declares only DRM_BRIDGE_OP_EDID
- If the previous bridge declares DRM_BRIDGE_OP_MODES, set
&drm_bridge_connector.bridge_modes to NULL and set
&drm_bridge_connector.bridge_edid to the later bridge.
- Although EDID detection capability has higher priority, this
operation is for balance and makes sense.
Case 3: the later bridge declares both of them
- Assign later bridge as &drm_bridge_connector.bridge_edid and
and &drm_bridge_connector.bridge_modes to this bridge.
- Just leave transfer of these two capabilities as before.
Signed-off-by: Damon Ding <damon.ding@rock-chips.com>
Suggested-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Tested-by: Heiko Stuebner <heiko@sntech.de> (on rk3588)
Link: https://patch.msgid.link/20251217093321.3108939-2-damon.ding@rock-chips.com
Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Add a test case to verify correct synchronization between concurrent
readers and a revocation.
The test setup involves:
1. Consumer 1 enters the critical section (SRCU read lock) and verifies
access to the resource.
2. Provider attempts to revoke the resource. This should block until
Consumer 1 releases the lock.
3. Consumer 2 attempts to enter the critical section while revocation
is pending. It should see the resource as revoked (NULL).
4. Consumer 1 exits, allowing the revocation to complete.
This ensures that the SRCU mechanism correctly enforces grace periods
and that new readers are properly prevented from accessing the resource
once revocation has begun.
A way to run the test:
$ ./tools/testing/kunit/kunit.py run \
--kconfig_add CONFIG_REVOCABLE_KUNIT_TEST=y \
--kconfig_add CONFIG_PROVE_LOCKING=y \
--kconfig_add CONFIG_DEBUG_KERNEL=y \
--kconfig_add CONFIG_DEBUG_INFO=y \
--kconfig_add CONFIG_DEBUG_INFO_DWARF5=y \
--kconfig_add CONFIG_KASAN=y \
--kconfig_add CONFIG_DETECT_HUNG_TASK=y \
--kconfig_add CONFIG_DEFAULT_HUNG_TASK_TIMEOUT="10" \
--arch=x86_64 --raw_output=all \
revocable_test
Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>
Link: https://patch.msgid.link/20260129143733.45618-5-tzungbi@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The struct revocable handle stores the SRCU read-side index (idx) for
the duration of a resource access. If multiple threads share the same
struct revocable instance, they race on writing to the idx field,
corrupting the SRCU state and potentially causing unsafe unlocks.
Refactor the API to replace revocable_alloc()/revocable_free() with
revocable_init()/revocable_deinit(). This change requires the caller
to provide the storage for struct revocable.
By moving storage ownership to the caller, the API ensures that
concurrent users maintain their own private idx storage, eliminating
the race condition.
Reported-by: Johan Hovold <johan@kernel.org>
Closes: https://lore.kernel.org/all/20260124170535.11756-4-johan@kernel.org/
Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>
Link: https://patch.msgid.link/20260129143733.45618-4-tzungbi@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add a test to verify that revocable_alloc() correctly handles race
conditions where the provider is being released.
The test covers three scenarios:
1. Allocating from a NULL provider.
2. Allocating from a provider that has been detached (pointer is NULL).
3. Allocating from a provider that is in the process of destruction
(refcount is 0), simulating a race between revocable_alloc() and
revocable_provider_release().
A way to run the test:
$ ./tools/testing/kunit/kunit.py run \
--kconfig_add CONFIG_REVOCABLE_KUNIT_TEST=y \
--kconfig_add CONFIG_PROVE_LOCKING=y \
--kconfig_add CONFIG_DEBUG_KERNEL=y \
--kconfig_add CONFIG_DEBUG_INFO=y \
--kconfig_add CONFIG_DEBUG_INFO_DWARF5=y \
--kconfig_add CONFIG_KASAN=y \
--kconfig_add CONFIG_DETECT_HUNG_TASK=y \
--kconfig_add CONFIG_DEFAULT_HUNG_TASK_TIMEOUT="10" \
--arch=x86_64 --raw_output=all \
revocable_test
Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>
Link: https://patch.msgid.link/20260129143733.45618-3-tzungbi@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There are two race conditions when allocating a revocable instance:
1. After a struct revocable_provider is revoked, the caller might still
hold a dangling pointer to it. A subsequent call to
revocable_alloc() can trigger a use-after-free.
2. If revocable_provider_release() runs concurrently with
revocable_alloc(), the memory of struct revocable_provider can be
accessed during or after kfree().
To fix these:
- Manage the lifetime of struct revocable_provider using RCU. Annotate
pointers to it with __rcu and use kfree_rcu() for deallocation.
- Update revocable_alloc() to safely acquire a reference using RCU
primitives.
- Update revocable_provider_revoke() to take a double pointer (`**rp`).
It atomically NULLs out the caller's pointer before starting
revocation. This prevents the caller from holding a dangling pointer.
- Drop devm_revocable_provider_alloc(). The devm-managed model cannot
support the required double-pointer semantic for safe pointer nulling.
Reported-by: Johan Hovold <johan@kernel.org>
Closes: https://lore.kernel.org/all/aXdy-b3GOJkzGqYo@hovoldconsulting.com/
Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>
Link: https://patch.msgid.link/20260129143733.45618-2-tzungbi@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Prevent display corruption observed after restart, hotplug, or unplug
operations on Meteor Lake and newer platforms. The issue is caused by
DSS clock gating affecting DSC logic when pipe power wells are disabled.
Apply this WA by disabling DSS clock gating for the affected pipes
before turning off their power wells. This avoids DSC corruption on
external displays.
v2: Use single intel_de_rmw() (Jani)
Switch to use drm_dbg_kms() instead of drm_printf() (Jani)
Remove WA number from commit message (Suraj)
rename dss_clock_gating_enable_disable() to
dss_pipe_gating_enable_disable();
v3: Do not use open ended display version when checking
wa (Matt)
WA: 22021048059
BSpec: 690991, 666241
Signed-off-by: Mika Kahola <mika.kahola@intel.com>
Reviewed-by: Suraj Kandpal <suraj.kandpal@intel.com>
Link: https://patch.msgid.link/20260202140242.704234-1-mika.kahola@intel.com
Consider the following sequence on a CPU configured with nohz_full:
1) A task P runs in cgroup A, and cgroup A becomes throttled due to CFS
bandwidth control. The gse (cgroup A) where the task P attached is
dequeued and the CPU switches to idle.
2) Before cgroup A is unthrottled, task P is migrated from cgroup A to
another cgroup B (not throttled).
During sched_move_task(), the task P is observed as queued but not
running, and therefore no resched_curr() is triggered.
3) Since the CPU is nohz_full, it remains in do_idle() waiting for an
explicit scheduling event, i.e., resched_curr().
4) For kernel <= 5.10: Later, cgroup A is unthrottled. However, the task
P has already been migrated out of cgroup A, so unthrottle_cfs_rq()
may observe load_weight == 0 and return early without resched_curr()
called. For kernel >= 6.6: The unthrottling path normally triggers
`resched_curr()` almost cases even when no runnable tasks remain in the
unthrottled cgroup, preventing the idle stall described above. However,
if cgroup A is removed before it gets unthrottled, the unthrottling path
for cgroup A is never executed. In a result, no `resched_curr()` can be
called.
5) At this point, the task P is runnable in cgroup B (not throttled), but
the CPU remains in do_idle() with no pending reschedule point. The
system stays in this state until an unrelated event (e.g. a new task
wakeup or any cases) that can trigger a resched_curr() breaks the
nohz_full idle state, and then the task P finally gets scheduled.
The root cause is that sched_move_task() may classify the task as only
queued, not running, and therefore fails to trigger a resched_curr(),
while the later unthrottling path no longer has visibility of the
migrated task.
Preserve the existing behavior for running tasks by issuing
resched_curr(), and explicitly invoke check_preempt_curr() for tasks
that were queued at the time of migration. This ensures that runnable
tasks are reconsidered for scheduling even when nohz_full suppresses
periodic ticks.
Fixes: 29f59db3a7 ("sched: group-scheduler core")
Signed-off-by: Zicheng Qu <quzicheng@huawei.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: K Prateek Nayak <kprateek.nayak@amd.com>
Reviewed-by: Aaron Lu <ziqianlu@bytedance.com>
Tested-by: Aaron Lu <ziqianlu@bytedance.com>
Link: https://patch.msgid.link/20260130083438.1122457-1-quzicheng@huawei.com
Use %pe format specifier for printing PTR_ERR() error values
to make error messages more readable.
Found by Coccinelle:
./cpufreq_schedutil.c:685:49-56: WARNING: Consider using %pe to print PTR_ERR()
Signed-off-by: zenghongling <zenghongling@kylinos.cn>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://patch.msgid.link/20260120083333.148385-1-zenghongling@kylinos.cn
CPU0 becomes overloaded when hosting a CPU-bound RT task, a non-CPU-bound
RT task, and a CFS task stuck in kernel space. When other CPUs switch from
RT to non-RT tasks, RT load balancing (LB) is triggered; with
HAVE_RT_PUSH_IPI enabled, they send IPIs to CPU0 to drive the execution
of rto_push_irq_work_func. During push_rt_task on CPU0,
if next_task->prio < rq->donor->prio, resched_curr() sets NEED_RESCHED
and after the push operation completes, CPU0 calls rto_next_cpu().
Since only CPU0 is overloaded in this scenario, rto_next_cpu() should
ideally return -1 (no further IPI needed).
However, multiple CPUs invoking tell_cpu_to_push() during LB increments
rd->rto_loop_next. Even when rd->rto_cpu is set to -1, the mismatch between
rd->rto_loop and rd->rto_loop_next forces rto_next_cpu() to restart its
search from -1. With CPU0 remaining overloaded (satisfying rt_nr_migratory
&& rt_nr_total > 1), it gets reselected, causing CPU0 to queue irq_work to
itself and send self-IPIs repeatedly. As long as CPU0 stays overloaded and
other CPUs run pull_rt_tasks(), it falls into an infinite self-IPI loop,
which triggers a CPU hardlockup due to continuous self-interrupts.
The trigging scenario is as follows:
cpu0 cpu1 cpu2
pull_rt_task
tell_cpu_to_push
<------------irq_work_queue_on
rto_push_irq_work_func
push_rt_task
resched_curr(rq) pull_rt_task
rto_next_cpu tell_cpu_to_push
<-------------------------- atomic_inc(rto_loop_next)
rd->rto_loop != next
rto_next_cpu
irq_work_queue_on
rto_push_irq_work_func
Fix redundant self-IPI by filtering the initiating CPU in rto_next_cpu().
This solution has been verified to effectively eliminate spurious self-IPIs
and prevent CPU hardlockup scenarios.
Fixes: 4bdced5c9a ("sched/rt: Simplify the IPI based RT balancing logic")
Suggested-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Suggested-by: K Prateek Nayak <kprateek.nayak@amd.com>
Signed-off-by: Chen Jinghuang <chenjinghuang2@huawei.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Reviewed-by: Valentin Schneider <vschneid@redhat.com>
Link: https://patch.msgid.link/20260122012533.673768-1-chenjinghuang2@huawei.com
Read-mostly sched_clock_irqtime may share the same cacheline with
frequently updated nohz struct. Make it as static_key to avoid
false sharing issue.
The only user of disable_sched_clock_irqtime()
is tsc_.*mark_unstable() which may be invoked under atomic context
and require a workqueue to disable static_key. But both of them
calls clear_sched_clock_stable() just before doing
disable_sched_clock_irqtime(). We can reuse
"sched_clock_work" to also disable sched_clock_irqtime().
One additional case need to handle is if the tsc is marked unstable
before late_initcall() phase, sched_clock_work will not be invoked
and sched_clock_irqtime will stay enabled although clock is unstable:
tsc_init()
enable_sched_clock_irqtime() # irqtime accounting is enabled here
...
if (unsynchronized_tsc()) # true
mark_tsc_unstable()
clear_sched_clock_stable()
__sched_clock_stable_early = 0;
...
if (static_key_count(&sched_clock_running.key) == 2)
# Only happens at sched_clock_init_late()
__clear_sched_clock_stable(); # Never executed
...
# late_initcall() phase
sched_clock_init_late()
if (__sched_clock_stable_early) # Already false
__set_sched_clock_stable(); # sched_clock is never marked stable
# TSC unstable, but sched_clock_work won't run to disable irqtime
So we need to disable_sched_clock_irqtime() in sched_clock_init_late()
if clock is unstable.
Reported-by: Benjamin Lei <benjamin.lei@intel.com>
Suggested-by: K Prateek Nayak <kprateek.nayak@amd.com>
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Suggested-by: Shrikanth Hegde <sshegde@linux.ibm.com>
Signed-off-by: Wangyang Guo <wangyang.guo@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: K Prateek Nayak <kprateek.nayak@amd.com>
Reviewed-by: Tim Chen <tim.c.chen@linux.intel.com>
Reviewed-by: Tianyou Li <tianyou.li@intel.com>
Reviewed-by: Shrikanth Hegde <sshegde@linux.ibm.com>
Tested-by: K Prateek Nayak <kprateek.nayak@amd.com>
Link: https://patch.msgid.link/20260127072509.2627346-1-wangyang.guo@intel.com
Add a new kselftest to verify that the total_bw value in
/sys/kernel/debug/sched/debug remains consistent across all CPUs
under different sched_ext BPF program states:
1. Before a BPF scheduler is loaded
2. While a BPF scheduler is loaded and active
3. After a BPF scheduler is unloaded
The test runs CPU stress threads to ensure DL server bandwidth
values stabilize before checking consistency. This helps catch
potential issues with DL server bandwidth accounting during
sched_ext transitions.
Co-developed-by: Andrea Righi <arighi@nvidia.com>
Signed-off-by: Andrea Righi <arighi@nvidia.com>
Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Christian Loehle <christian.loehle@arm.com>
Link: https://patch.msgid.link/20260126100050.3854740-8-arighi@nvidia.com
Add a selftest to validate the correct behavior of the deadline server
for the ext_sched_class.
Co-developed-by: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: Andrea Righi <arighi@nvidia.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com>
Tested-by: Christian Loehle <christian.loehle@arm.com>
Link: https://patch.msgid.link/20260126100050.3854740-7-arighi@nvidia.com
There are two problems with sched_server_write_common() that can cause the
dl_server to malfunction upon attempting to change the parameters:
1) when, after having disabled the dl_server by setting runtime=0, it is
enabled again while tasks are already enqueued. In this case is_active would
still be 0 and dl_server_start() would not be called.
2) when dl_server_apply_params() would fail, runtime is not applied and does
not reflect the new state.
Instead have dl_server_start() check its actual dl_runtime, and have
sched_server_write_common() unconditionally (re)start the dl_server. It will
automatically stop if there isn't anything to do, so spurious activation is
harmless -- while failing to start it is a problem.
While there, move the printk out of the locked region and make it symmetric,
also printing on enable.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://patch.msgid.link/20260203103407.GK1282955@noisy.programming.kicks-ass.net
When a sched_ext server is loaded, tasks in the fair class are
automatically moved to the sched_ext class. Add support to modify the
ext server parameters similar to how the fair server parameters are
modified.
Re-use common code between ext and fair servers as needed.
Co-developed-by: Andrea Righi <arighi@nvidia.com>
Signed-off-by: Andrea Righi <arighi@nvidia.com>
Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Juri Lelli <juri.lelli@redhat.com>
Tested-by: Christian Loehle <christian.loehle@arm.com>
Link: https://patch.msgid.link/20260126100050.3854740-6-arighi@nvidia.com
sched_ext currently suffers starvation due to RT. The same workload when
converted to EXT can get zero runtime if RT is 100% running, causing EXT
processes to stall. Fix it by adding a DL server for EXT.
A kselftest is also included later to confirm that both DL servers are
functioning correctly:
# ./runner -t rt_stall
===== START =====
TEST: rt_stall
DESCRIPTION: Verify that RT tasks cannot stall SCHED_EXT tasks
OUTPUT:
TAP version 13
1..1
# Runtime of FAIR task (PID 1511) is 0.250000 seconds
# Runtime of RT task (PID 1512) is 4.750000 seconds
# FAIR task got 5.00% of total runtime
ok 1 PASS: FAIR task got more than 4.00% of runtime
TAP version 13
1..1
# Runtime of EXT task (PID 1514) is 0.250000 seconds
# Runtime of RT task (PID 1515) is 4.750000 seconds
# EXT task got 5.00% of total runtime
ok 2 PASS: EXT task got more than 4.00% of runtime
TAP version 13
1..1
# Runtime of FAIR task (PID 1517) is 0.250000 seconds
# Runtime of RT task (PID 1518) is 4.750000 seconds
# FAIR task got 5.00% of total runtime
ok 3 PASS: FAIR task got more than 4.00% of runtime
TAP version 13
1..1
# Runtime of EXT task (PID 1521) is 0.250000 seconds
# Runtime of RT task (PID 1522) is 4.750000 seconds
# EXT task got 5.00% of total runtime
ok 4 PASS: EXT task got more than 4.00% of runtime
ok 1 rt_stall #
===== END =====
Co-developed-by: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: Andrea Righi <arighi@nvidia.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Juri Lelli <juri.lelli@redhat.com>
Tested-by: Christian Loehle <christian.loehle@arm.com>
Link: https://patch.msgid.link/20260126100050.3854740-5-arighi@nvidia.com
Currently the DL server interface for applying parameters checks
CFS-internals to identify if the server is active. This is error-prone
and makes it difficult when adding new servers in the future.
Fix it, by using dl_server_active() which is also used by the DL server
code to determine if the DL server was started.
Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Juri Lelli <juri.lelli@redhat.com>
Reviewed-by: Andrea Righi <arighi@nvidia.com>
Acked-by: Tejun Heo <tj@kernel.org>
Tested-by: Christian Loehle <christian.loehle@arm.com>
Link: https://patch.msgid.link/20260126100050.3854740-4-arighi@nvidia.com
Updating "ppos" on error conditions does not make much sense. The pattern
is to return the error code directly without modifying the position, or
modify the position on success and return the number of bytes written.
Since on success, the return value of apply is 0, there is no point in
modifying ppos either. Fix it by removing all this and just returning
error code or number of bytes written on success.
Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Juri Lelli <juri.lelli@redhat.com>
Reviewed-by: Andrea Righi <arighi@nvidia.com>
Acked-by: Tejun Heo <tj@kernel.org>
Tested-by: Christian Loehle <christian.loehle@arm.com>
Link: https://patch.msgid.link/20260126100050.3854740-3-arighi@nvidia.com
The defer params were not cleared in __dl_clear_params. Clear them.
Without this is some of my test cases are flaking and the DL timer is
not starting correctly AFAICS.
Fixes: a110a81c52 ("sched/deadline: Deferrable dl server")
Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Andrea Righi <arighi@nvidia.com>
Acked-by: Juri Lelli <juri.lelli@redhat.com>
Tested-by: Christian Loehle <christian.loehle@arm.com>
Link: https://patch.msgid.link/20260126100050.3854740-2-arighi@nvidia.com
Instead of relying on fixed relation to the display probe flag,
add configfs attribute to allow an administrator to configure
desired PF operation mode in a more flexible way.
Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Reviewed-by: Piotr Piórkowski <piotr.piorkowski@intel.com>
Acked-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patch.msgid.link/20260121214218.2817-6-michal.wajdeczko@intel.com
Instead of doing guesses each time during the runtime, set flag
admin_only once during PF's initialization.
Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Reviewed-by: Piotr Piórkowski <piotr.piorkowski@intel.com>
Acked-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patch.msgid.link/20260127210501.794-1-michal.wajdeczko@intel.com
The max_vfs parameter used by the Xe driver has its default value
definition, but it could be altered by the module parameter or by
the device specific configfs attribute.
To avoid mistakes or code duplication, always rely on the configfs
helper (or stub), which will provide necessary fallback if needed.
Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Reviewed-by: Piotr Piórkowski <piotr.piorkowski@intel.com>
Acked-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patch.msgid.link/20260121214218.2817-4-michal.wajdeczko@intel.com
For local includes we should use "" notation, not <>.
Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Reviewed-by: Piotr Piórkowski <piotr.piorkowski@intel.com>
Acked-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patch.msgid.link/20260121214218.2817-3-michal.wajdeczko@intel.com
We already have most of Xe defaults defined in xe_module.c,
where we use them for the modparam initializations, but some
were defined elsewhere, which breaks the consistency.
Introduce xe_defaults.h file, that will act as a placeholder
for all our default values, and can be used from other places.
Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Reviewed-by: Piotr Piórkowski <piotr.piorkowski@intel.com>
Acked-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patch.msgid.link/20260121214218.2817-2-michal.wajdeczko@intel.com
Fix two memory leaks in the gfs2_fill_super() error handling path when
transitioning a filesystem to read-write mode fails.
First leak: kthread objects (thread_struct, task_struct, etc.)
When gfs2_freeze_lock_shared() fails after init_threads() succeeds, the
created kernel threads (logd and quotad) are never destroyed. This
occurs because the fail_per_node label doesn't call
gfs2_destroy_threads().
Second leak: quota bitmap buffer (8192 bytes)
When gfs2_make_fs_rw() fails after gfs2_quota_init() succeeds but
before other operations complete, the allocated quota bitmap is never
freed.
The fix moves thread cleanup to the fail_per_node label to handle all
error paths uniformly. gfs2_destroy_threads() is safe to call
unconditionally as it checks for NULL pointers. Quota cleanup is added
in gfs2_make_fs_rw() to properly handle the withdrawal case where
quota initialization succeeds but the filesystem is then withdrawn.
Thread leak backtrace (gfs2_freeze_lock_shared failure):
unreferenced object 0xffff88801d7bca80 (size 4480):
copy_process+0x3a1/0x4670 kernel/fork.c:2422
kernel_clone+0xf3/0x6e0 kernel/fork.c:2779
kthread_create_on_node+0x100/0x150 kernel/kthread.c:478
init_threads+0xab/0x350 fs/gfs2/ops_fstype.c:611
gfs2_fill_super+0xe5c/0x1240 fs/gfs2/ops_fstype.c:1265
Quota leak backtrace (gfs2_make_fs_rw failure):
unreferenced object 0xffff88812de7c000 (size 8192):
gfs2_quota_init+0xe5/0x820 fs/gfs2/quota.c:1409
gfs2_make_fs_rw+0x7a/0xe0 fs/gfs2/super.c:149
gfs2_fill_super+0xfbb/0x1240 fs/gfs2/ops_fstype.c:1275
Reported-by: syzbot+aac438d7a1c44071e04b@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=aac438d7a1c44071e04b
Fixes: 6c7410f449 ("gfs2: gfs2_freeze_lock_shared cleanup")
Fixes: b66f723bb5 ("gfs2: Improve gfs2_make_fs_rw error handling")
Link: https://lore.kernel.org/all/20260131062509.77974-1-kartikey406@gmail.com/T/ [v1]
Signed-off-by: Deepanshu Kartikey <kartikey406@gmail.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
alloc_gcs() returns an error-encoded pointer on failure, which comes
from do_mmap(), not NULL.
The current NULL check fails to detect errors, which could lead to using
an invalid GCS address.
Use IS_ERR_VALUE() to properly detect errors, consistent with the
check in gcs_alloc_thread_stack().
Fixes: b57180c75c ("arm64/gcs: Implement shadow stack prctl() interface")
Reviewed-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Will Deacon <will@kernel.org>
Clang warns (or errors with CONFIG_WERROR=y / W=e):
drivers/gpu/drm/panel/panel-ilitek-ili9882t.c:95:16: error: initializer overrides prior initialization of this subobject [-Werror,-Winitializer-overrides]
95 | .vbr_enable = 0,
| ^
drivers/gpu/drm/panel/panel-ilitek-ili9882t.c:90:16: note: previous initialization is here
90 | .vbr_enable = false,
| ^~~~~
drivers/gpu/drm/panel/panel-ilitek-ili9882t.c:97:19: error: initializer overrides prior initialization of this subobject [-Werror,-Winitializer-overrides]
97 | .rc_model_size = DSC_RC_MODEL_SIZE_CONST,
| ^~~~~~~~~~~~~~~~~~~~~~~
include/drm/display/drm_dsc.h:22:38: note: expanded from macro 'DSC_RC_MODEL_SIZE_CONST'
22 | #define DSC_RC_MODEL_SIZE_CONST 8192
| ^~~~
drivers/gpu/drm/panel/panel-ilitek-ili9882t.c:91:19: note: previous initialization is here
91 | .rc_model_size = DSC_RC_MODEL_SIZE_CONST,
| ^~~~~~~~~~~~~~~~~~~~~~~
include/drm/display/drm_dsc.h:22:38: note: expanded from macro 'DSC_RC_MODEL_SIZE_CONST'
22 | #define DSC_RC_MODEL_SIZE_CONST 8192
| ^~~~
drivers/gpu/drm/panel/panel-ilitek-ili9882t.c:132:25: error: initializer overrides prior initialization of this subobject [-Werror,-Winitializer-overrides]
132 | .initial_scale_value = 32,
| ^~
drivers/gpu/drm/panel/panel-ilitek-ili9882t.c:126:25: note: previous initialization is here
126 | .initial_scale_value = 32,
| ^~
drivers/gpu/drm/panel/panel-ilitek-ili9882t.c:133:20: error: initializer overrides prior initialization of this subobject [-Werror,-Winitializer-overrides]
133 | .nfl_bpg_offset = 3511,
| ^~~~
drivers/gpu/drm/panel/panel-ilitek-ili9882t.c:108:20: note: previous initialization is here
108 | .nfl_bpg_offset = 1402,
| ^~~~
GCC would warn about this in the same manner but its version,
-Woverride-init, is disabled for a normal kernel build in
scripts/Makefile.warn. For clang, -Wextra in drivers/gpu/drm/Makefile
turns it back but GCC respects turning it off earlier in the command
line.
Of all the duplicate fields in the initializer, only nfl_bpg_offset is a
different value. Clear up the duplicate initializers, keeping the
'false' value for .vbr_enable, as it is bool, and the second value for
.nfl_bpg_offset, assuming it is the correct one since it was the one
tested in the original change.
Fixes: 65ce1f5834 ("drm/panel: ilitek-ili9882t: Switch Tianma TL121BVMS07 to DSC 120Hz mode")
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Link: https://patch.msgid.link/20260114-panel-ilitek-ili9882t-fix-override-init-v1-1-1d69a2b096df@kernel.org
Signed-off-by: Maxime Ripard <mripard@kernel.org>
The interrupt handler iio_trigger_generic_data_rdy_poll() will invoke other
interrupt handlers and this supposed to happen from hard interrupt context.
Use IRQF_NO_THREAD to forbid forced-threading.
Fixes: 0ab13674a9 ("media: pci: mgb4: Added Digiteq Automotive MGB4 driver")
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/20260128095540.863589-21-bigeasy@linutronix.de
Add upper limit check for pixel clock for WCL.
For prior platforms though the bspec mentions the dotclock limits, however
these are intentionally not enforced to avoid regressions, unless real
issues are observed.
BSpec: 49199, 68912
Signed-off-by: Chaitanya Kumar Borah <chaitanya.kumar.borah@intel.com>
Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Link: https://patch.msgid.link/20260202103731.357416-18-ankit.k.nautiyal@intel.com
Add upper limit check for pixel clock for DISPLAY_VER >= 30.
Limits don't apply when DSC is enabled.
The helper returns the upper limit for the platforms, capped to the
max dotclock (khz).
For the currently supported versions of HDMI, pixel clock is already
limited to 600Mhz so nothing needs to be done there as of now.
v2:
- Add this limit to the new helper.
v3:
- Rename helper to intel_max_uncompressed_dotclock(). (Imre)
- Limit only for PTL and cap the limit to max_dotclock. (Imre)
BSpec: 49199, 68912
Signed-off-by: Chaitanya Kumar Borah <chaitanya.kumar.borah@intel.com>
Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Link: https://patch.msgid.link/20260202103731.357416-17-ankit.k.nautiyal@intel.com
Introduce for_each_joiner_candidate(), intel_dp_joiner_candidate_valid()
and intel_dp_joiner_candidate_valid() to remove duplicated joiner
enumeration and validity checks across DP SST and MST paths.
Suggested-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Link: https://patch.msgid.link/20260202103731.357416-16-ankit.k.nautiyal@intel.com
Account for DSC slice overhead bubbles and adjust the pixel rate while
checking the pixel rate against the max dotclock limits.
v2: Add missing assignment for dsc_slice_count in
mst_connector_mode_valid_ctx(). (Imre)
v3: Explicitly pass dsc_slice_count as 0 for Non-DSC case. (Imre)
Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Link: https://patch.msgid.link/20260202103731.357416-15-ankit.k.nautiyal@intel.com
Make dsc_slice_count closer to the block where it is used and promote it
from u8 to int. This aligns it with upcoming DSC bubble pixel-rate
adjustments, where the slice count participates in wider arithmetic.
Currently, for non-eDP (DP/DP_MST) cases the slice count is computed only
inside intel_dp_dsc_mode_valid() and is not used by the caller. Once DSC
bubble handling is added, dp_mode_valid() will need access to its own local
slice count for non-eDP cases as well.
Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Link: https://patch.msgid.link/20260202103731.357416-14-ankit.k.nautiyal@intel.com
Add intel_dp_dotclk_valid() helper, that checks the required pixel rate
against platform dotclock limit. With joined pipes the effective dotclock
limit depends upon the number of joined pipes.
Call the helper from the mode_valid phase and from the compute_config
phase where we need to check the limits for the given target clock for a
given joiner candidate.
v2: Rename the helper to intel_dp_dotclk_valid(). (Imre)
Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Link: https://patch.msgid.link/20260202103731.357416-13-ankit.k.nautiyal@intel.com
The helpers intel_dp_num_joined_pipes() and intel_dp_needs_joiner() are no
longer used now that joiner selection iterates over all candidates.
Remove them.
Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Link: https://patch.msgid.link/20260202103731.357416-12-ankit.k.nautiyal@intel.com
Similar to the DP SST, refactor mst_stream_compute_config() to iterate
over joiner candidates and select the minimal joiner configuration that
satisfies the mode requirements. This prepares the logic for future changes
that will consider DSC slice overhead.
v2:
- Move the check for dotclock in the new helper and check for both DSC and
non-DSC case. In case the check fails for non-DSC, fallback to DSC
configuration. (Imre)
- Propagate the return value from the core helper:
mst_stream_compute_link_for_joined_pipes(). (Imre)
v3:
- Use num_joined_pipes instead of num_pipes. (Imre)
v4:
- Switch to 'ret == 0' for break condition to match SST code.
Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Link: https://patch.msgid.link/20260202103731.357416-11-ankit.k.nautiyal@intel.com
Move the joiner-dependent portion of mst_stream_compute_config() into
mst_stream_compute_link_for_joined_pipes(), which computes the MST link
configuration for a specific num_joined_pipes.
Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Link: https://patch.msgid.link/20260202103731.357416-10-ankit.k.nautiyal@intel.com
