From 440d52b370b03b366fd26ace36bab20552116145 Mon Sep 17 00:00:00 2001 From: Rob Clark Date: Fri, 13 Sep 2024 13:23:01 -0700 Subject: drm/sched: Fix dynamic job-flow control race Fixes a race condition reported here: https://github.com/AsahiLinux/linux/issues/309#issuecomment-2238968609 The whole premise of lockless access to a single-producer-single- consumer queue is that there is just a single producer and single consumer. That means we can't call drm_sched_can_queue() (which is about queueing more work to the hw, not to the spsc queue) from anywhere other than the consumer (wq). This call in the producer is just an optimization to avoid scheduling the consuming worker if it cannot yet queue more work to the hw. It is safe to drop this optimization to avoid the race condition. Suggested-by: Asahi Lina Fixes: a78422e9dff3 ("drm/sched: implement dynamic job-flow control") Closes: https://github.com/AsahiLinux/linux/issues/309 Cc: stable@vger.kernel.org Signed-off-by: Rob Clark Reviewed-by: Danilo Krummrich Tested-by: Janne Grunau Signed-off-by: Danilo Krummrich Link: https://patchwork.freedesktop.org/patch/msgid/20240913202301.16772-1-robdclark@gmail.com --- include/drm/gpu_scheduler.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include') diff --git a/include/drm/gpu_scheduler.h b/include/drm/gpu_scheduler.h index 5acc64954a88..e28bc649b5c9 100644 --- a/include/drm/gpu_scheduler.h +++ b/include/drm/gpu_scheduler.h @@ -574,7 +574,7 @@ void drm_sched_entity_modify_sched(struct drm_sched_entity *entity, void drm_sched_tdr_queue_imm(struct drm_gpu_scheduler *sched); void drm_sched_job_cleanup(struct drm_sched_job *job); -void drm_sched_wakeup(struct drm_gpu_scheduler *sched, struct drm_sched_entity *entity); +void drm_sched_wakeup(struct drm_gpu_scheduler *sched); bool drm_sched_wqueue_ready(struct drm_gpu_scheduler *sched); void drm_sched_wqueue_stop(struct drm_gpu_scheduler *sched); void drm_sched_wqueue_start(struct drm_gpu_scheduler *sched); -- cgit From f0fa69b5011a45394554fb8061d74fee4d7cd72c Mon Sep 17 00:00:00 2001 From: Derek Foreman Date: Tue, 27 Aug 2024 11:39:04 -0500 Subject: drm/connector: hdmi: Fix writing Dynamic Range Mastering infoframes The largest infoframe we create is the DRM (Dynamic Range Mastering) infoframe which is 26 bytes + a 4 byte header, for a total of 30 bytes. With HDMI_MAX_INFOFRAME_SIZE set to 29 bytes, as it is now, we allocate too little space to pack a DRM infoframe in write_device_infoframe(), leading to an ENOSPC return from hdmi_infoframe_pack(), and never calling the connector's write_infoframe() vfunc. Instead of having HDMI_MAX_INFOFRAME_SIZE defined in two places, replace HDMI_MAX_INFOFRAME_SIZE with HDMI_INFOFRAME_SIZE(MAX) and make MAX 27 bytes - which is defined by the HDMI specification to be the largest infoframe payload. Fixes: f378b77227bc ("drm/connector: hdmi: Add Infoframes generation") Fixes: c602e4959a0c ("drm/connector: hdmi: Create Infoframe DebugFS entries") Signed-off-by: Derek Foreman Acked-by: Maxime Ripard Reviewed-by: Jani Nikula Link: https://patchwork.freedesktop.org/patch/msgid/20240827163918.48160-1-derek.foreman@collabora.com Signed-off-by: Maxime Ripard --- drivers/gpu/drm/display/drm_hdmi_state_helper.c | 4 +--- drivers/gpu/drm/drm_debugfs.c | 4 +--- include/linux/hdmi.h | 9 +++++++++ 3 files changed, 11 insertions(+), 6 deletions(-) (limited to 'include') diff --git a/drivers/gpu/drm/display/drm_hdmi_state_helper.c b/drivers/gpu/drm/display/drm_hdmi_state_helper.c index 7854820089ec..feb7a3a75981 100644 --- a/drivers/gpu/drm/display/drm_hdmi_state_helper.c +++ b/drivers/gpu/drm/display/drm_hdmi_state_helper.c @@ -521,8 +521,6 @@ int drm_atomic_helper_connector_hdmi_check(struct drm_connector *connector, } EXPORT_SYMBOL(drm_atomic_helper_connector_hdmi_check); -#define HDMI_MAX_INFOFRAME_SIZE 29 - static int clear_device_infoframe(struct drm_connector *connector, enum hdmi_infoframe_type type) { @@ -563,7 +561,7 @@ static int write_device_infoframe(struct drm_connector *connector, { const struct drm_connector_hdmi_funcs *funcs = connector->hdmi.funcs; struct drm_device *dev = connector->dev; - u8 buffer[HDMI_MAX_INFOFRAME_SIZE]; + u8 buffer[HDMI_INFOFRAME_SIZE(MAX)]; int ret; int len; diff --git a/drivers/gpu/drm/drm_debugfs.c b/drivers/gpu/drm/drm_debugfs.c index 6b239a24f1df..9d3e6dd68810 100644 --- a/drivers/gpu/drm/drm_debugfs.c +++ b/drivers/gpu/drm/drm_debugfs.c @@ -520,8 +520,6 @@ static const struct file_operations drm_connector_fops = { .write = connector_write }; -#define HDMI_MAX_INFOFRAME_SIZE 29 - static ssize_t audio_infoframe_read(struct file *filp, char __user *ubuf, size_t count, loff_t *ppos) { @@ -579,7 +577,7 @@ static ssize_t _f##_read_infoframe(struct file *filp, \ struct drm_connector *connector; \ union hdmi_infoframe *frame; \ struct drm_device *dev; \ - u8 buf[HDMI_MAX_INFOFRAME_SIZE]; \ + u8 buf[HDMI_INFOFRAME_SIZE(MAX)]; \ ssize_t len = 0; \ \ connector = filp->private_data; \ diff --git a/include/linux/hdmi.h b/include/linux/hdmi.h index 3bb87bf6bc65..455f855bc084 100644 --- a/include/linux/hdmi.h +++ b/include/linux/hdmi.h @@ -59,6 +59,15 @@ enum hdmi_infoframe_type { #define HDMI_DRM_INFOFRAME_SIZE 26 #define HDMI_VENDOR_INFOFRAME_SIZE 4 +/* + * HDMI 1.3a table 5-14 states that the largest InfoFrame_length is 27, + * not including the packet header or checksum byte. We include the + * checksum byte in HDMI_INFOFRAME_HEADER_SIZE, so this should allow + * HDMI_INFOFRAME_SIZE(MAX) to be the largest buffer we could ever need + * for any HDMI infoframe. + */ +#define HDMI_MAX_INFOFRAME_SIZE 27 + #define HDMI_INFOFRAME_SIZE(type) \ (HDMI_INFOFRAME_HEADER_SIZE + HDMI_ ## type ## _INFOFRAME_SIZE) -- cgit