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Maksim Kiselev 2d623c94fb aoe: avoid potential deadlock at set_capacity ... [ Upstream commit e169bd4fb2 ] Move set_capacity() outside of the section procected by (&d->lock). To avoid possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- [1] lock(&bdev->bd_size_lock); local_irq_disable(); [2] lock(&d->lock); [3] lock(&bdev->bd_size_lock); <Interrupt> [4] lock(&d->lock); *** DEADLOCK *** Where [1](&bdev->bd_size_lock) hold by zram_add()->set_capacity(). [2]lock(&d->lock) hold by aoeblk_gdalloc(). And aoeblk_gdalloc() is trying to acquire [3](&bdev->bd_size_lock) at set_capacity() call. In this situation an attempt to acquire [4]lock(&d->lock) from aoecmd_cfg_rsp() will lead to deadlock. So the simplest solution is breaking lock dependency [2](&d->lock) -> [3](&bdev->bd_size_lock) by moving set_capacity() outside. Signed-off-by: Maksim Kiselev <bigunclemax@gmail.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20240124072436.3745720-2-bigunclemax@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org>		History 2024-03-01 13:26:26 +01:00
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aoe.h	aoe: Avoid flush_scheduled_work() usage	2022-05-01 06:41:41 -06:00
aoeblk.c	aoe: avoid potential deadlock at set_capacity	2024-03-01 13:26:26 +01:00
aoechr.c	aoe: remove unnecessary oom message	2021-06-09 09:41:48 -06:00
aoecmd.c	aoe: Avoid flush_scheduled_work() usage	2022-05-01 06:41:41 -06:00
aoedev.c	block: remove blk_cleanup_disk	2022-06-28 06:33:15 -06:00
aoemain.c	aoe: Avoid flush_scheduled_work() usage	2022-05-01 06:41:41 -06:00
aoenet.c	aoe: update copyright date	2013-07-03 16:08:05 -07:00
Makefile	treewide: Add SPDX license identifier - Makefile/Kconfig	2019-05-21 10:50:46 +02:00