** Attachment added: "ext4.oops" https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1839849/+attachment/5282203/+files/ext4.oops
-- 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/1839849 Title: ext4 oops when running xfstests on cifs - kernel 5.0.0-x (Disco) only Status in linux package in Ubuntu: Confirmed Status in linux source package in Disco: Confirmed Bug description: I've found an issue with kernel 5.0.0-24 while trying to verify LP#1824981 in a qemu guest - xfstests running on CIFS triggers a crash in ext4 with the following signature: BUG: unable to handle kernel NULL pointer dereference at 000000000000012c #PF error: [normal kernel read fault] Oops: 0000 [#1] SMP PTI CPU: 3 PID: 24980 Comm: 223 Not tainted 5.0.0-24-generic #25-Ubuntu RIP: 0010:call_filldir+0xa2/0x140 [...] Call Trace: ext4_readdir+0x869/0xa80 iterate_dir+0x9a/0x1b0 __x64_sys_getdents+0xa6/0x140 ? __x64_sys_getdents+0x140/0x140 do_syscall_64+0x5a/0x110 The full oops is attached below. I've tested on the following kernels, always in the Disco guest: *Reproduced -> 5.0.0-7 (built that one), 5.0.0-13, 5.0.0-21, 5.0.0-23, 5.0.0-24 (proposed) *No Issue -> 4.18.0-25 (from Cosmic), 5.2.0-10 (from Eoan), and 5.0, 5.1 and 5.2 from mainline builds (https://kernel.ubuntu.com/~kernel-ppa/mainline/) To trigger that I've ran the xfstests on a cifs mount point according to the instructions in https://wiki.samba.org/index.php/Xfstesting- cifs . The issue shows around test generic/208 usually. I've started a "manual" bisect - isolated all commits from v5.0..5.0.0-7, excluded all related with debian folder (and efi- lockdown, due to their complexity) and I'm reverting in a binary search fashion. Reverted 105 commits and still reproduced, and in the next set I've failed to build. I'll investigate the build fault and also I'll try to reproduce in a Bionic VM with bionic-hwe kernel version 5.0 . To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1839849/+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
