Avoid angering kcsan by serialising the read of the pm_events with the write in rps_diable_interrupts. [ 6268.713419] BUG: KCSAN: data-race in intel_rps_park [i915] / rps_work [i915] [ 6268.713437] [ 6268.713449] write to 0xffff8881eda8efac of 4 bytes by task 1127 on cpu 3: [ 6268.713680] intel_rps_park+0x136/0x260 [i915] [ 6268.713905] __gt_park+0x61/0xa0 [i915] [ 6268.714128] ____intel_wakeref_put_last+0x42/0x90 [i915] [ 6268.714352] __intel_wakeref_put_work+0xd3/0xf0 [i915] [ 6268.714369] process_one_work+0x3b1/0x690 [ 6268.714384] worker_thread+0x80/0x670 [ 6268.714398] kthread+0x19a/0x1e0 [ 6268.714412] ret_from_fork+0x1f/0x30 [ 6268.714423] [ 6268.714435] read to 0xffff8881eda8efac of 4 bytes by task 950 on cpu 2: [ 6268.714664] rps_work+0xc2/0x680 [i915] [ 6268.714679] process_one_work+0x3b1/0x690 [ 6268.714693] worker_thread+0x80/0x670 [ 6268.714707] kthread+0x19a/0x1e0 [ 6268.714720] ret_from_fork+0x1f/0x30 Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> --- drivers/gpu/drm/i915/gt/intel_rps.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/gt/intel_rps.c b/drivers/gpu/drm/i915/gt/intel_rps.c index 506738dede16..dbecfb5a5bb1 100644 --- a/drivers/gpu/drm/i915/gt/intel_rps.c +++ b/drivers/gpu/drm/i915/gt/intel_rps.c @@ -1459,12 +1459,12 @@ static void rps_work(struct work_struct *work) u32 pm_iir = 0; spin_lock_irq(>->irq_lock); - pm_iir = fetch_and_zero(&rps->pm_iir); + pm_iir = fetch_and_zero(&rps->pm_iir) & rps->pm_events; client_boost = atomic_read(&rps->num_waiters); spin_unlock_irq(>->irq_lock); /* Make sure we didn't queue anything we're not going to process. */ - if ((pm_iir & rps->pm_events) == 0 && !client_boost) + if (!pm_iir && !client_boost) goto out; mutex_lock(&rps->lock); -- 2.20.1 _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
