6.7-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ming Qian <ming.qian@xxxxxxx> [ Upstream commit f9c8ddce2fe3b767582f299d03fc8fb85943568c ] mutext_lock should not be called in condition of wait_event, otherwise, when CONFIG_DEBUG_ATOMIC_SLEEP is enabled, we may meet the following warning: do not call blocking ops when !TASK_RUNNING; state=2 WARNING: CPU: 5 PID: 741 at kernel/sched/core.c:9859 __might_sleep+0x80/0xa4 Hardware name: Freescale i.MX8QM MEK (DT) pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : __might_sleep+0x80/0xa4 lr : __might_sleep+0x80/0xa4 sp : ffffffc0123738a0 x29: ffffffc0123738a0 x28: ffffffc009194c48 x27: ffffffc00bbc1050 x26: ffffff8814b282f0 x25: ffffff8814b280d0 x24: ffffff8814b28080 x23: 0000000000000001 x22: 0000000000000032 x21: ffffffc00bbc1000 x20: 000000000000011b x19: ffffffc009324670 x18: 00000000fffffffd x17: 30303c5b20746120 x16: 74657320323d6574 x15: 617473203b474e49 x14: 00058b5b8b9aa1f1 x13: ffffffc00903cda0 x12: 00000000d744fcc9 x11: 000000000000001c x10: 00000000000009a0 x9 : ffffffc0090201f4 x8 : ffffff8828245000 x7 : 0000000000000001 x6 : 0000000000000001 x5 : 00000000410fd080 x4 : 0000000000000002 x3 : ffffff8815aab4c8 x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffffff8828244600 Call trace: __might_sleep+0x80/0xa4 mutex_lock+0x2c/0x80 sync_session_response+0x110/0x310 vpu_session_send_cmd+0x18c/0x244 vpu_session_start+0x38/0x70 vdec_start_session+0x1b4/0x3e0 vpu_vb2_start_streaming+0xa0/0x1c4 vb2_start_streaming+0x74/0x160 vb2_core_qbuf+0x488/0x650 vb2_qbuf+0x9c/0x100 v4l2_m2m_qbuf+0x7c/0x224 v4l2_m2m_ioctl_qbuf+0x20/0x2c v4l_qbuf+0x50/0x6c __video_do_ioctl+0x174/0x3f0 video_usercopy+0x210/0x7cc video_ioctl2+0x20/0x30 v4l2_ioctl+0x48/0x6c we need to refine check_is_responsed() to remove the mutext_lock, each cmd has a monotonically increasing id, and cmds are executed sequentially, so we can check the id of the last reponsed cmd, then determine whether a command has been responded or not. Signed-off-by: Ming Qian <ming.qian@xxxxxxx> CC: Xiaolei Wang <xiaolei.wang@xxxxxxxxxxxxx> Signed-off-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/media/platform/amphion/vpu.h | 3 ++- drivers/media/platform/amphion/vpu_cmds.c | 28 ++++++++--------------- drivers/media/platform/amphion/vpu_v4l2.c | 1 + 3 files changed, 12 insertions(+), 20 deletions(-) diff --git a/drivers/media/platform/amphion/vpu.h b/drivers/media/platform/amphion/vpu.h index 5a701f64289e..0246cf0ac3a8 100644 --- a/drivers/media/platform/amphion/vpu.h +++ b/drivers/media/platform/amphion/vpu.h @@ -154,7 +154,6 @@ struct vpu_core { struct vpu_mbox tx_type; struct vpu_mbox tx_data; struct vpu_mbox rx; - unsigned long cmd_seq; wait_queue_head_t ack_wq; struct completion cmp; @@ -253,6 +252,8 @@ struct vpu_inst { struct list_head cmd_q; void *pending; + unsigned long cmd_seq; + atomic_long_t last_response_cmd; struct vpu_inst_ops *ops; const struct vpu_format *formats; diff --git a/drivers/media/platform/amphion/vpu_cmds.c b/drivers/media/platform/amphion/vpu_cmds.c index c2337812573e..5695f5c1cb3e 100644 --- a/drivers/media/platform/amphion/vpu_cmds.c +++ b/drivers/media/platform/amphion/vpu_cmds.c @@ -32,6 +32,7 @@ struct vpu_cmd_t { struct vpu_cmd_request *request; struct vpu_rpc_event *pkt; unsigned long key; + atomic_long_t *last_response_cmd; }; static struct vpu_cmd_request vpu_cmd_requests[] = { @@ -115,6 +116,8 @@ static void vpu_free_cmd(struct vpu_cmd_t *cmd) { if (!cmd) return; + if (cmd->last_response_cmd) + atomic_long_set(cmd->last_response_cmd, cmd->key); vfree(cmd->pkt); vfree(cmd); } @@ -172,7 +175,8 @@ static int vpu_request_cmd(struct vpu_inst *inst, u32 id, void *data, return -ENOMEM; mutex_lock(&core->cmd_lock); - cmd->key = core->cmd_seq++; + cmd->key = ++inst->cmd_seq; + cmd->last_response_cmd = &inst->last_response_cmd; if (key) *key = cmd->key; if (sync) @@ -246,26 +250,12 @@ void vpu_clear_request(struct vpu_inst *inst) static bool check_is_responsed(struct vpu_inst *inst, unsigned long key) { - struct vpu_core *core = inst->core; - struct vpu_cmd_t *cmd; - bool flag = true; + unsigned long last_response = atomic_long_read(&inst->last_response_cmd); - mutex_lock(&core->cmd_lock); - cmd = inst->pending; - if (cmd && key == cmd->key) { - flag = false; - goto exit; - } - list_for_each_entry(cmd, &inst->cmd_q, list) { - if (key == cmd->key) { - flag = false; - break; - } - } -exit: - mutex_unlock(&core->cmd_lock); + if (key <= last_response && (last_response - key) < (ULONG_MAX >> 1)) + return true; - return flag; + return false; } static int sync_session_response(struct vpu_inst *inst, unsigned long key, long timeout, int try) diff --git a/drivers/media/platform/amphion/vpu_v4l2.c b/drivers/media/platform/amphion/vpu_v4l2.c index 0f6e4c666440..d7e0de49b3dc 100644 --- a/drivers/media/platform/amphion/vpu_v4l2.c +++ b/drivers/media/platform/amphion/vpu_v4l2.c @@ -716,6 +716,7 @@ int vpu_v4l2_open(struct file *file, struct vpu_inst *inst) func = &vpu->decoder; atomic_set(&inst->ref_count, 0); + atomic_long_set(&inst->last_response_cmd, 0); vpu_inst_get(inst); inst->vpu = vpu; inst->core = vpu_request_core(vpu, inst->type); -- 2.43.0