The might_sleep() annotation in alua_rtpg_queue() is not correct since the command completion code may call this function from atomic context. Calling alua_rtpg_queue() from atomic context in the command completion path is fine since request submitters must hold an sdev reference until command execution has completed. This patch fixes the following kernel complaint: BUG: sleeping function called from invalid context at drivers/scsi/device_handler/scsi_dh_alua.c:992 Call Trace: dump_stack_lvl+0xac/0x100 __might_resched+0x284/0x2c8 alua_rtpg_queue+0x3c/0x98 [scsi_dh_alua] alua_check+0x122/0x250 [scsi_dh_alua] alua_check_sense+0x172/0x228 [scsi_dh_alua] scsi_check_sense+0x8a/0x2e0 scsi_decide_disposition+0x286/0x298 scsi_complete+0x6a/0x108 blk_complete_reqs+0x6e/0x88 __do_softirq+0x13e/0x6b8 __irq_exit_rcu+0x14a/0x170 irq_exit_rcu+0x22/0x50 do_ext_irq+0x10a/0x1d0 Reported-by: Steffen Maier <maier@xxxxxxxxxxxxx> Reviewed-by: Martin Wilck <mwilck@xxxxxxxx> Tested-by: Steffen Maier <maier@xxxxxxxxxxxxx> Signed-off-by: Bart Van Assche <bvanassche@xxxxxxx> --- drivers/scsi/device_handler/scsi_dh_alua.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c index 55a5073248f8..362fa631f39b 100644 --- a/drivers/scsi/device_handler/scsi_dh_alua.c +++ b/drivers/scsi/device_handler/scsi_dh_alua.c @@ -987,6 +987,9 @@ static void alua_rtpg_work(struct work_struct *work) * * Returns true if and only if alua_rtpg_work() will be called asynchronously. * That function is responsible for calling @qdata->fn(). + * + * Context: may be called from atomic context (alua_check()) only if the caller + * holds an sdev reference. */ static bool alua_rtpg_queue(struct alua_port_group *pg, struct scsi_device *sdev, @@ -995,8 +998,6 @@ static bool alua_rtpg_queue(struct alua_port_group *pg, int start_queue = 0; unsigned long flags; - might_sleep(); - if (WARN_ON_ONCE(!pg) || scsi_device_get(sdev)) return false;
