'd like to perform a reverse bisect to figure out which commit upstream fixes this regression. It would be very helpful to know the last kernel that had this issue and the first kernel that did not.
Can you test the following kernels and report back? We are looking for the earliest kernel version that doesn't have this bug: v4.1-rc4: http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.1-rc4-unstable/ v4.1-rc3: http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.1-rc3-unstable/ v4.1-rc2: http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.1-rc2-unstable/ v4.1-rc1: http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.1-rc1-unstable/ You don't have to test every kernel. We are just looking for the last kernel that had the bug and the first kernel that did not. Once we know these two versions, we can bisect between them. ** Tags added: performing-bisect -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1439780 Title: [Hyper-V] Fiber Channel critical target error Status in linux package in Ubuntu: Confirmed Bug description: System details: Linux version 3.19.0-11-generic (apw@gloin) (gcc version 4.9.2 (Ubuntu 4.9.2-10ubuntu12) ) #11~lp1423343v201503311833 SMP Tue Mar 31 17:40:01 UTC 2015 (Ubuntu 3.19.0-11.11~lp1423343v201503311833-generic 3.19.3) Ubuntu 3.19.0-11 Ubuntu Vivid 15.04 64bit custom kernel Platform: WS2012R2 Using a fiber channel disk partition ( dev/sde1 in this example) outputs the following error: [ 1307.744496] blk_update_request: critical target error, dev sde, sector 0 [ 1396.052488] blk_update_request: critical target error, dev sde, sector 0 [ 1456.216570] blk_update_request: critical target error, dev sde, sector 0 Creating a partition works, reading too, but first time writing it hangs for around 20 seconds and after a couple more writes the partition goes into read-only mode: #echo "test1" > test1.txt *hangs for 30 seconds* blk_update_request: critical target error, dev sde, sector 0 # echo "test2" > test2.txt blk_update_request: critical target error, dev sde, sector 289671192 Aborting journal on device sde1-8. EXT4-fs error (device sde1): ext4_journal_check_start:56: Detected aborted journal EXT4-fs (sde1): Remounting filesystem read-only # echo "test string" > sample.txt -bash: sample.txt: Read-only file system Dmesg log: [ 461.284362] blk_update_request: critical target error, dev sde, sector 0 [ 484.845659] EXT4-fs (sde1): mounted filesystem with ordered data mode. Opts: (null) [ 548.988377] blk_update_request: critical target error, dev sde, sector 0 [ 609.216340] blk_update_request: critical target error, dev sde, sector 289671192 [ 609.221812] Aborting journal on device sde1-8. [ 612.237503] EXT4-fs error (device sde1): ext4_journal_check_start:56: Detected aborted journal [ 612.249529] EXT4-fs (sde1): Remounting filesystem read-only Additional info: cat /proc/version_signature Ubuntu 3.19.0-11.11~lp1423343v201503311833-generic 3.19.3 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1439780/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp