On Tue, Sep 11, 2018 at 10:52:26PM +0100, David Howells wrote: > > [ 5.057003] RIP: 0010:reconfigure_super+0x47/0x210 > > Can you tell me what file and line this is? > > Also, do you know which filesystem was involved? > > > I don't find a more recent version of this patch in patchwork on kernel.org, > > so I am replying to this one. My apologies if there are more recent versions. > > I've just updated my tree with some fixes. Can you try: > > https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git/log/ > > branch "fsinfo"? > Unfortunately, that does not work either. With v4.19-rc3-40-g09f0a401de37: [ 8.505130] BUG: unable to handle kernel NULL pointer dereference at 0000000000000030 [ 8.506237] PGD 800000001d81e067 P4D 800000001d81e067 PUD 1dfb1067 PMD 0 [ 8.506669] Oops: 0000 [#1] SMP PTI [ 8.506915] CPU: 0 PID: 1180 Comm: umount Not tainted 4.19.0-rc3+ #1 [ 8.507052] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.11.2-0-gf9626ccb91-prebuilt.qemu-project.org 04/01/2014 [ 8.507672] RIP: 0010:reconfigure_super+0x47/0x210 [ 8.507877] Code: d4 01 00 00 44 8b a3 30 02 00 00 45 85 e4 0f 85 9d 01 00 00 a8 01 48 89 fd 75 4f 48 89 df 45 31 ed e8 ad 4f 01 00 48 8b 45 00 <48> 4 [ 8.508222] RSP: 0018:ffffb3794015bdd0 EFLAGS: 00000246 [ 8.508345] RAX: 0000000000000000 RBX: ffff9d855df27800 RCX: ffff9d855df278b8 [ 8.508479] RDX: ffff9d855df27848 RSI: 0000000000000000 RDI: ffffffff8d54a9a8 [ 8.508617] RBP: ffffb3794015be00 R08: 00000000000000d8 R09: 0000000000000000 [ 8.508752] R10: ffffb3794011fce8 R11: 0000000000000001 R12: 0000000000000000 [ 8.508885] R13: 0000000000000001 R14: ffff9d855effc920 R15: 0000000000000000 [ 8.509056] FS: 00007f6712967500(0000) GS:ffff9d855f200000(0000) knlGS:0000000000000000 [ 8.509217] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 8.509332] CR2: 0000000000000030 CR3: 000000001dfe0000 CR4: 00000000000006f0 [ 8.509516] Call Trace: [ 8.510121] do_umount_root+0x7b/0xb0 [ 8.510244] ksys_umount+0x250/0x3e0 [ 8.510535] ? vfs_write+0x13f/0x190 [ 8.510629] __x64_sys_umount+0xd/0x10 [ 8.510722] do_syscall_64+0x39/0xe0 [ 8.510810] entry_SYSCALL_64_after_hwframe+0x44/0xa9 Guenter