From 0cd1262de7b7509bbbcd650a9918e8895dee6d73 Mon Sep 17 00:00:00 2001 From: Matt Roper Date: Tue, 12 Jan 2016 07:13:37 -0800 Subject: [PATCH] drm/i915: Handle error paths during watermark sanitization properly (v3) sanitize_watermarks() does not properly handle errors returned by drm_atomic_helper_duplicate_state(). Make failures drop locks before returning. We also change the lock of connection_mutex to a drm_modeset_lock_all_ctx() to make sure any EDEADLK's are handled earlier. v2: Change call to lock connetion_mutex with a call to drm_modeset_lock_all_ctx(). This ensures that any lock contention is handled earlier and drm_atomic_helper_duplicate_state() won't return EDEADLK. (Maarten) v3: Drop locks properly in more error paths. (Maarten) Cc: Daniel Vetter Cc: Maarten Lankhorst Signed-off-by: Matt Roper Reviewed-by: Maarten Lankhorst Link: http://patchwork.freedesktop.org/patch/msgid/1452611617-32144-1-git-send-email-matthew.d.roper@intel.com --- drivers/gpu/drm/i915/intel_display.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index 9c87d57..3b79981 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -15355,17 +15355,17 @@ static void sanitize_watermarks(struct drm_device *dev) */ drm_modeset_acquire_init(&ctx, 0); retry: - ret = drm_modeset_lock(&dev->mode_config.connection_mutex, &ctx); + ret = drm_modeset_lock_all_ctx(dev, &ctx); if (ret == -EDEADLK) { drm_modeset_backoff(&ctx); goto retry; } else if (WARN_ON(ret)) { - return; + goto fail; } state = drm_atomic_helper_duplicate_state(dev, &ctx); if (WARN_ON(IS_ERR(state))) - return; + goto fail; /* * Hardware readout is the only time we don't want to calculate @@ -15388,7 +15388,7 @@ retry: * BIOS-programmed watermarks untouched and hope for the best. */ WARN(true, "Could not determine valid watermarks for inherited state\n"); - return; + goto fail; } /* Write calculated watermark values back */ @@ -15401,6 +15401,7 @@ retry: } drm_atomic_state_free(state); +fail: drm_modeset_drop_locks(&ctx); drm_modeset_acquire_fini(&ctx); } -- 2.7.4