The new patch has been upload. The modification points are as follower:
1. delete the period. 2. change 'W' to lowercase. 3. add a Reviewed-by tag. On 6/27/22 06:40, Yuwen Chen wrote:
When the user mounts the erofs second times, the decompression thread may hung. The problem happens due to a sequence of steps like the following: 1) Task A called z_erofs_load_lzma_config which obtain all of the node from the z_erofs_lzma_head. 2) At this time, task B called the z_erofs_lzma_decompress and wanted to get a node. But the z_erofs_lzma_head was empty, the Task B had to sleep. 3) Task A release nodes and push nodes into the z_erofs_lzma_head. But task B was still sleeping. One example report when the hung happens: task:kworker/u3:1 state:D stack:14384 pid: 86 ppid: 2 flags:0x00004000 Workqueue: erofs_unzipd z_erofs_decompressqueue_work Call Trace: <TASK> __schedule+0x281/0x760 schedule+0x49/0xb0 z_erofs_lzma_decompress+0x4bc/0x580 ? cpu_core_flags+0x10/0x10 z_erofs_decompress_pcluster+0x49b/0xba0 ? __update_load_avg_se+0x2b0/0x330 ? __update_load_avg_se+0x2b0/0x330 ? update_load_avg+0x5f/0x690 ? update_load_avg+0x5f/0x690 ? set_next_entity+0xbd/0x110 ? _raw_spin_unlock+0xd/0x20 z_erofs_decompress_queue.isra.0+0x2e/0x50 z_erofs_decompressqueue_work+0x30/0x60 process_one_work+0x1d3/0x3a0 worker_thread+0x45/0x3a0 ? process_one_work+0x3a0/0x3a0 kthread+0xe2/0x110 ? kthread_complete_and_exit+0x20/0x20 ret_from_fork+0x22/0x30 </TASK> Signed-off-by: Yuwen Chen <[email protected]> Reviewed-by: Gao Xiang <[email protected]> --- fs/erofs/decompressor_lzma.c | 1 + 1 file changed, 1 insertion(+) diff --git a/fs/erofs/decompressor_lzma.c b/fs/erofs/decompressor_lzma.c index 05a3063cf2bc..5e59b3f523eb 100644 --- a/fs/erofs/decompressor_lzma.c +++ b/fs/erofs/decompressor_lzma.c @@ -143,6 +143,7 @@ int z_erofs_load_lzma_config(struct super_block *sb, DBG_BUGON(z_erofs_lzma_head); z_erofs_lzma_head = head; spin_unlock(&z_erofs_lzma_lock); + wake_up_all(&z_erofs_lzma_wq);z_erofs_lzma_max_dictsize = dict_size;mutex_unlock(&lzma_resize_mutex);
