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Maksim Kiselev 2499fa286f aoe: avoid potential deadlock at set_capacity ... commit e169bd4fb2 upstream. 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> [ Larry: backport to 5.15.y. Minor conflict resolved due to missing commit d9c2bd252a aoe: add error handling support for add_disk() ] Signed-off-by: Larry Bassel <larry.bassel@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		History 2025-07-17 18:30:48 +02:00
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aoe.h	aoe: replace ->special use with private data in the request	2018-11-10 08:03:49 -07:00
aoeblk.c	aoe: avoid potential deadlock at set_capacity	2025-07-17 18:30:48 +02:00
aoechr.c	aoe: remove unnecessary oom message	2021-06-09 09:41:48 -06:00
aoecmd.c	aoe: fix the potential use-after-free problem in more places	2024-10-17 15:11:39 +02:00
aoedev.c	aoe: clean device rq_list in aoedev_downdev()	2025-06-27 11:05:35 +01:00
aoemain.c	aoe: add __exit annotation	2018-12-16 09:01:38 -07:00
aoenet.c	aoe: fix the potential use-after-free problem in aoecmd_cfg_pkts	2024-03-26 18:21:15 -04:00
Makefile	treewide: Add SPDX license identifier - Makefile/Kconfig	2019-05-21 10:50:46 +02:00