Commit 901206f7 authored Feb 15, 2022 by Bart Van Assche Committed by Greg Kroah-Hartman Mar 02, 2022

RDMA/ib_srp: Fix a deadlock

[ Upstream commit 081bdc9fe05bb23248f5effb6f811da3da4b8252 ]

Remove the flush_workqueue(system_long_wq) call since flushing
system_long_wq is deadlock-prone and since that call is redundant with a
preceding cancel_work_sync()

Link: https://lore.kernel.org/r/20220215210511.28303-3-bvanassche@acm.org


Fixes: ef6c49d8 ("IB/srp: Eliminate state SRP_TARGET_DEAD")
Reported-by:  <syzbot+831661966588c802aae9@syzkaller.appspotmail.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

parent b7e2b91f

drivers/infiniband/ulp/srp/ib_srp.c

+4 −2

Original line number	Diff line number	Diff line
		@@ -4222,9 +4222,11 @@ static void srp_remove_one(struct ib_device device, void client_data)
		spin_unlock(&host->target_lock);

		/*
		* Wait for tl_err and target port removal tasks.
		* srp_queue_remove_work() queues a call to
		* srp_remove_target(). The latter function cancels
		* target->tl_err_work so waiting for the remove works to
		* finish is sufficient.
		*/
		flush_workqueue(system_long_wq);
		flush_workqueue(srp_remove_wq);

		kfree(host);