Hello, Rafael. On Sun, Dec 26, 2010 at 11:16:26PM +0100, Rafael J. Wysocki wrote: > [ 319.281892] ======================================================= > [ 319.281893] [ INFO: possible circular locking dependency detected ] > [ 319.281894] 2.6.37-rc7+ #16 > [ 319.281895] ------------------------------------------------------- > [ 319.281896] kworker/1:0/13333 is trying to acquire lock: > [ 319.281897] (&bdev->bd_mutex){+.+.+.}, at: [<ffffffff811271a6>] revalidate_disk+0x56/0x90 > [ 319.281902] > [ 319.281903] but task is already holding lock: > [ 319.281903] (&ap->scsi_scan_mutex){+.+...}, at: [<ffffffff81360420>] ata_scsi_dev_rescan+0x30/0x120 This dependency is true. > [ 319.281910] -> #3 (&ap->scsi_scan_mutex){+.+...}: > [ 319.281927] -> #2 ((&ap->scsi_rescan_task)){+.+...}: > [ 319.281937] -> #1 (events){+.+.+.}: > [ 319.281970] -> #0 (&bdev->bd_mutex){+.+.+.}: But the above is bogus. It's only linked through the system_wq. The current lockdep notation assumes single execution resource and triggers spuriously in certain cases. I'll think about how to relax it. Thank you. -- tejun -- 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