block: avoid calling blkg_free() in atomic context
blkg_free() can currently be called in atomic context, either spin lock is
held, or run in rcu callback. Meantime either request queue's release
handler or ->pd_free_fn can sleep.
Fix the issue by scheduling a work function for freeing blkcg_gq the
instance.
[ 148.553894] BUG: sleeping function called from invalid context at block/blk-sysfs.c:767
[ 148.557381] in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 0, name: swapper/13
[ 148.560741] preempt_count: 101, expected: 0
[ 148.562577] RCU nest depth: 0, expected: 0
[ 148.564379] 1 lock held by swapper/13/0:
[ 148.566127] #0:
ffffffff82615f80 (rcu_callback){....}-{0:0}, at: rcu_lock_acquire+0x0/0x1b
[ 148.569640] Preemption disabled at:
[ 148.569642] [<
ffffffff8123f9c3>] ___slab_alloc+0x554/0x661
[ 148.573559] CPU: 13 PID: 0 Comm: swapper/13 Kdump: loaded Not tainted 5.17.0_up+ #110
[ 148.576834] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-1.fc33 04/01/2014
[ 148.579768] Call Trace:
[ 148.580567] <IRQ>
[ 148.581262] dump_stack_lvl+0x56/0x7c
[ 148.582367] ? ___slab_alloc+0x554/0x661
[ 148.583526] __might_resched+0x1af/0x1c8
[ 148.584678] blk_release_queue+0x24/0x109
[ 148.585861] kobject_cleanup+0xc9/0xfe
[ 148.586979] blkg_free+0x46/0x63
[ 148.587962] rcu_do_batch+0x1c5/0x3db
[ 148.589057] rcu_core+0x14a/0x184
[ 148.590065] __do_softirq+0x14d/0x2c7
[ 148.591167] __irq_exit_rcu+0x7a/0xd4
[ 148.592264] sysvec_apic_timer_interrupt+0x82/0xa5
[ 148.593649] </IRQ>
[ 148.594354] <TASK>
[ 148.595058] asm_sysvec_apic_timer_interrupt+0x12/0x20
Cc: Tejun Heo <tj@kernel.org>
Fixes:
0a9a25ca7843 ("block: let blkcg_gq grab request queue's refcnt")
Reported-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/linux-block/20220322093322.GA27283@lst.de/
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20220323011308.2010380-1-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
projects / linux-block.git / commit