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| author | Yuwen Chen <chenyuwen1@meizu.com> | 2022-06-27 01:40:41 +0300 |
|---|---|---|
| committer | Gao Xiang <hsiangkao@linux.alibaba.com> | 2022-07-09 01:32:29 +0300 |
| commit | 2df7c4bd7c1d2bc5ece5e9ed19dbd386810c2a65 (patch) | |
| tree | 07ba6bbc825183db80b8fde7705eb8d3eac18b09 /fs/erofs | |
| parent | f94bc517b4992aeddeeb30a4ac813cb4d1d81241 (diff) | |
| download | linux-2df7c4bd7c1d2bc5ece5e9ed19dbd386810c2a65.tar.xz | |
erofs: wake up all waiters after z_erofs_lzma_head ready
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 <chenyuwen1@meizu.com>
Fixes: 622ceaddb764 ("erofs: lzma compression support")
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20220626224041.4288-1-chenyuwen1@meizu.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Diffstat (limited to 'fs/erofs')
| -rw-r--r-- | fs/erofs/decompressor_lzma.c | 1 |
1 files changed, 1 insertions, 0 deletions
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 @@ again: 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); |