On 2018/3/20 23:14, Bart Van Assche wrote: > On Tue, 2018-03-20 at 16:12 +0100, Xose Vazquez Perez wrote: >> On 03/20/2018 03:58 PM, Bart Van Assche wrote: >> >>> It is on purpose that the SCSI core does not remove stale SCSI device nodes. >>> If you want that these stale SCSI device nodes get removed automatically, >>> two possible approaches are (there might be other approaches): >>> * Write a new user space daemon that periodically checks for stale devices >>> (e.g. by running grep -aH . /sys/class/scsi_device/*/*/state | >>> grep -v running) and that triggers a SCSI rescan if any stale devices are >>> found. >>> * Write a udev rule that listens for SDEV_UA=REPORTED_LUNS_DATA_HAS_CHANGED >>> and that triggers a SCSI rescan if this event is triggered by the kernel. >> >> There are some "remove" flags in rescan-scsi-bus.sh: >> https://github.com/hreinecke/sg3_utils/blob/d4dbbede04db21c206e4c2acc1cf766117f003c3/scripts/rescan-scsi-bus.sh#L1080 >> >> -r enables removing of devices [default: disabled] >> --forceremove: Remove stale devices (DANGEROUS) >> --forcerescan: Remove and readd existing devices (DANGEROUS) > > Last time I checked the rescan-scsi-bus.sh script relied on the SCSI sysfs > delete attribute to remove stale devices. That is the mechanism that can > trigger a deadlock in the kernel. > > Bart. > Hi Bart, Is there any special operation or conditions to reproduce the dead lock? I have use SCSI sysfs delete atrribute to remove stale devices in my previous patch and test many times, but I haven't encountered any deadlock problems. Regards, Chongyun -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
