From 922c2877827dcc474f3079e464773ab31ac13b79 Mon Sep 17 00:00:00 2001 From: Hersen Wu Date: Tue, 30 Apr 2024 14:24:17 -0400 Subject: [PATCH] drm/amd/display: Fix writeback job lock evasion within dm_crtc_high_irq [Why] Coverity report LOCK_EVASION warning. Access acrtc->wb_pending without lock wb_conn->job_lock. [How] Lock wb_conn->job_lock before accessing acrtc->wb_pending. Reviewed-by: Alex Hung Acked-by: Tom Chung Signed-off-by: Hersen Wu Tested-by: Daniel Wheeler Signed-off-by: Alex Deucher --- drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c index ee8da59a6ccc..5667db120399 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c @@ -597,12 +597,14 @@ static void dm_crtc_high_irq(void *interrupt_params) if (!acrtc) return; - if (acrtc->wb_pending) { - if (acrtc->wb_conn) { - spin_lock_irqsave(&acrtc->wb_conn->job_lock, flags); + if (acrtc->wb_conn) { + spin_lock_irqsave(&acrtc->wb_conn->job_lock, flags); + + if (acrtc->wb_pending) { job = list_first_entry_or_null(&acrtc->wb_conn->job_queue, struct drm_writeback_job, list_entry); + acrtc->wb_pending = false; spin_unlock_irqrestore(&acrtc->wb_conn->job_lock, flags); if (job) { @@ -620,8 +622,7 @@ static void dm_crtc_high_irq(void *interrupt_params) acrtc->dm_irq_params.stream, 0); } } else - DRM_ERROR("%s: no amdgpu_crtc wb_conn\n", __func__); - acrtc->wb_pending = false; + spin_unlock_irqrestore(&acrtc->wb_conn->job_lock, flags); } vrr_active = amdgpu_dm_crtc_vrr_active_irq(acrtc); -- 2.50.1