From: Bart Van Assche Date: Wed, 18 Jan 2023 18:05:57 +0000 (-0800) Subject: scsi: device_handler: alua: Remove a might_sleep() annotation X-Git-Tag: v6.6.7~3643^2~2 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=0bfe63d075789456e9589457b29d6f9c279e3252;p=platform%2Fkernel%2Flinux-starfive.git scsi: device_handler: alua: Remove a might_sleep() annotation 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 Link: https://lore.kernel.org/r/20230118180557.1212577-1-bvanassche@acm.org Reported-by: Steffen Maier Reviewed-by: Martin Wilck Tested-by: Steffen Maier Signed-off-by: Bart Van Assche Signed-off-by: Martin K. Petersen --- diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c index 49cc18a..29a2865 100644 --- a/drivers/scsi/device_handler/scsi_dh_alua.c +++ b/drivers/scsi/device_handler/scsi_dh_alua.c @@ -981,6 +981,9 @@ queue_rtpg: * * 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, @@ -989,8 +992,6 @@ 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;