From: Jackson.lee Date: Tue, 17 Dec 2024 04:51:23 +0000 (+0900) Subject: media: chips-media: wave5: Avoid race condition in the interrupt handler X-Git-Tag: io_uring-6.15-20250403~96^2~211 X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=ac35f768986610480a1c01323d9cf9f5eaf3ee9b;p=linux-block.git media: chips-media: wave5: Avoid race condition in the interrupt handler In case of multiple active instances, new interrupts can occur as soon as the current interrupt is cleared. If the driver reads the instance_info after clearing the interrupt, then there is no guarantee, that the instance_info is still valid for the current interrupt. Read the instance_info register for each interrupt before clearing the interrupt. Fixes: ed7276ed2fd0 ("media: chips-media: wave5: Add hrtimer based polling support") Cc: stable@vger.kernel.org Signed-off-by: Jackson.lee Signed-off-by: Nas Chung Reviewed-by: Nicolas Dufresne Signed-off-by: Sebastian Fricke Signed-off-by: Hans Verkuil --- diff --git a/drivers/media/platform/chips-media/wave5/wave5-vpu.c b/drivers/media/platform/chips-media/wave5/wave5-vpu.c index d1320298a0f7..5948a18958d1 100644 --- a/drivers/media/platform/chips-media/wave5/wave5-vpu.c +++ b/drivers/media/platform/chips-media/wave5/wave5-vpu.c @@ -55,12 +55,12 @@ static void wave5_vpu_handle_irq(void *dev_id) struct vpu_device *dev = dev_id; irq_reason = wave5_vdi_read_register(dev, W5_VPU_VINT_REASON); + seq_done = wave5_vdi_read_register(dev, W5_RET_SEQ_DONE_INSTANCE_INFO); + cmd_done = wave5_vdi_read_register(dev, W5_RET_QUEUE_CMD_DONE_INST); wave5_vdi_write_register(dev, W5_VPU_VINT_REASON_CLR, irq_reason); wave5_vdi_write_register(dev, W5_VPU_VINT_CLEAR, 0x1); list_for_each_entry(inst, &dev->instances, list) { - seq_done = wave5_vdi_read_register(dev, W5_RET_SEQ_DONE_INSTANCE_INFO); - cmd_done = wave5_vdi_read_register(dev, W5_RET_QUEUE_CMD_DONE_INST); if (irq_reason & BIT(INT_WAVE5_INIT_SEQ) || irq_reason & BIT(INT_WAVE5_ENC_SET_PARAM)) {