On 04/06/2012 07:36 PM, Daniel J Blueman wrote: > Hi Josef, Chris, > > When testing BTRFS with RAID 0 metadata on linux-3.4-rc1, we see > discard ranges exceeding the end of the block device [1], potentially > causing dataloss; when this occurs, filesystem writeback becomes > catatonic due to continual resubmission. > > Simply mounting with discard a raid0 metadata filesystem and copying > some data in [2] provokes the issue. > > Thanks, > Daniel > > --- [1] > > attempt to access beyond end of device > ram0: rw=129, want=8452072, limit=4096000 > ... > > --- [2] > > modprobe brd rd_size=2048000 (or boot with ramdisk_size=2048000) > mkfs.btrfs -m raid0 /dev/ram0 /dev/ram1 > mount /dev/ram0 /mnt -o discard > cd /mnt && tar -xvzf linux.tar.gz > <access beyond end of device and livelock> Thanks for the report, this bug shows we've miscalculated the length of discard extents. I'll send a patch for this soon. thanks, -- liubo -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
