From: Alexander Strakh <strakh@xxxxxxxxx> Driver scsi_lib.c might sleep in atomic context, because it calls scsi_device_put under spin_lock_irqsave. drivers/scsi/scsi_lib.c:356: spin_lock_irqsave(shost->host_lock, flags); scsi_device_put(sdev); Path to might_sleep macro from scsi_device_put: 1. scsi_device_put calls put_device at ./drivers/scsi/scsi.c:1111 2. put_device calls kobject_put at ./drivers/base/core.c:1038 3. kobject_put calls kref_put at ./lib/kobject.c 4. kref_put may call callback function kobject_release at ./lib/kref.c if refcount becomes zero, which might_sleep because it calls user event. Details: 4.1 kobject_cleanup calls kobject_uevent at ./lib/kobject.c:555 4.2 kobject_uevent calls kobject_uevent_env at ./lib/kobject_uevent.c:282 4.3 kobject_uevent_env calls call_usermodehelper_exec at ./include/linux/kmod.h:83 4.4 call_usermodehelper_exec calls wait_for_completion at ./kernel/kmod.c:481 4.5 wait_for_completion calls wait_for_common at ./kernel/sched.c:5710 4.5 wait_for_common calls might_sleep at ./kernels/sched.c:5692 Found by Linux Driver Verification project. Delete wrong sleeping function calls. Signed-off-by: Alexander Strakh <strakh@xxxxxxxxx> Cc: James Bottomley <James.Bottomley@xxxxxxxxxxxxxxxxxxxxx> Cc: Jens Axboe <jens.axboe@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- drivers/scsi/scsi_lib.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff -puN drivers/scsi/scsi_lib.c~scsi_libc-avoid-calling-scsi_device_put-from-under-host_lock drivers/scsi/scsi_lib.c --- a/drivers/scsi/scsi_lib.c~scsi_libc-avoid-calling-scsi_device_put-from-under-host_lock +++ a/drivers/scsi/scsi_lib.c @@ -353,9 +353,9 @@ static void scsi_single_lun_run(struct s spin_unlock_irqrestore(shost->host_lock, flags); blk_run_queue(sdev->request_queue); - spin_lock_irqsave(shost->host_lock, flags); scsi_device_put(sdev); + spin_lock_irqsave(shost->host_lock, flags); } out: spin_unlock_irqrestore(shost->host_lock, flags); _ -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
