Searched hist:"887554 ab96588de2917b6c8c73e552da082e5368" (Results 1 – 2 of 2) sorted by relevance
/linux/drivers/md/bcache/ |
H A D | writeback.c | diff 887554ab96588de2917b6c8c73e552da082e5368 Fri Feb 11 07:39:15 CET 2022 Mingzhe Zou <mingzhe.zou@easystack.cn> bcache: fixup multiple threads crash
When multiple threads to check btree nodes in parallel, the main thread wait for all threads to stop or CACHE_SET_IO_DISABLE flag:
wait_event_interruptible(check_state->wait, atomic_read(&check_state->started) == 0 || test_bit(CACHE_SET_IO_DISABLE, &c->flags));
However, the bch_btree_node_read and bch_btree_node_read_done maybe call bch_cache_set_error, then the CACHE_SET_IO_DISABLE will be set. If the flag already set, the main thread return error. At the same time, maybe some threads still running and read NULL pointer, the kernel will crash.
This patch change the event wait condition, the main thread must wait for all threads to stop.
Fixes: 8e7102273f597 ("bcache: make bch_btree_check() to be multithreaded") Signed-off-by: Mingzhe Zou <mingzhe.zou@easystack.cn> Cc: stable@vger.kernel.org # v5.7+ Signed-off-by: Coly Li <colyli@suse.de>
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H A D | btree.c | diff 887554ab96588de2917b6c8c73e552da082e5368 Fri Feb 11 07:39:15 CET 2022 Mingzhe Zou <mingzhe.zou@easystack.cn> bcache: fixup multiple threads crash
When multiple threads to check btree nodes in parallel, the main thread wait for all threads to stop or CACHE_SET_IO_DISABLE flag:
wait_event_interruptible(check_state->wait, atomic_read(&check_state->started) == 0 || test_bit(CACHE_SET_IO_DISABLE, &c->flags));
However, the bch_btree_node_read and bch_btree_node_read_done maybe call bch_cache_set_error, then the CACHE_SET_IO_DISABLE will be set. If the flag already set, the main thread return error. At the same time, maybe some threads still running and read NULL pointer, the kernel will crash.
This patch change the event wait condition, the main thread must wait for all threads to stop.
Fixes: 8e7102273f597 ("bcache: make bch_btree_check() to be multithreaded") Signed-off-by: Mingzhe Zou <mingzhe.zou@easystack.cn> Cc: stable@vger.kernel.org # v5.7+ Signed-off-by: Coly Li <colyli@suse.de>
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