Comment 2 for bug 1496438

Gabriel Rauter (raetiacorvus) wrote :

I get the same error when i try to do the following:

Start ubuntu:wily image trough docker and have the kernel sources mounted in a ro mountpoint.
Use overlayfs to have a rw version of it:
mount -t overlay overlay -o lowerdir=/linux-ro/,upperdir=/linux-up,workdir=/linux-work /linux
when i try to compile the kernel with make -j4 ... my system crashes after 1-2 sec

Host system is Archlinux with btrfs as filesystem.

Sep 16 20:21:34 Lilith kernel: BUG: unable to handle kernel NULL pointer dereference at 0000000000000334
Sep 16 20:21:34 Lilith kernel: IP: [<ffffffffa0468f43>] btrfs_sync_file+0xe3/0x380 [btrfs]
Sep 16 20:21:34 Lilith kernel: PGD 202916067 PUD 1308ce067 PMD 0
Sep 16 20:21:34 Lilith kernel: Oops: 0002 [#1] PREEMPT SMP
Sep 16 20:21:34 Lilith kernel: Modules linked in: overlay rfcomm veth cmac ecb fuse xt_conntrack ipt_MASQUERADE nf_nat_masquerade_ipv4 iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv
Sep 16 20:21:34 Lilith kernel: crc32c_generic btrfs xor raid6_pq sd_mod hid_generic usbhid hid uas usb_storage atkbd libps2 radeon ahci libahci ohci_pci ohci_hcd ehci_pci i2c_algo_bit ehci_
Sep 16 20:21:34 Lilith kernel: CPU: 2 PID: 27896 Comm: vdsomunge Not tainted 4.2.0-3-ARCH #1
Sep 16 20:21:34 Lilith kernel: Hardware name: To be filled by O.E.M. To be filled by O.E.M./SABERTOOTH 990FX, BIOS 1604 10/16/2012
Sep 16 20:21:34 Lilith kernel: task: ffff880132754b00 ti: ffff88018a054000 task.ti: ffff88018a054000
Sep 16 20:21:34 Lilith kernel: RIP: 0010:[<ffffffffa0468f43>] [<ffffffffa0468f43>] btrfs_sync_file+0xe3/0x380 [btrfs]
Sep 16 20:21:34 Lilith kernel: RSP: 0018:ffff88018a057e08 EFLAGS: 00010296
Sep 16 20:21:34 Lilith kernel: RAX: ffff880132754b00 RBX: ffff880015468900 RCX: 0000000000000000
Sep 16 20:21:34 Lilith kernel: RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff880201aeba58
Sep 16 20:21:34 Lilith kernel: RBP: ffff88018a057e98 R08: 0000000000000001 R09: ffff880015468900
Sep 16 20:21:34 Lilith kernel: R10: 00000000000002fc R11: 0000000000000246 R12: ffff880201aeba58
Sep 16 20:21:34 Lilith kernel: R13: ffff880201aeb9b0 R14: 0000000000000000 R15: 0000000000000000
Sep 16 20:21:34 Lilith kernel: FS: 00002ab262e61b40(0000) GS:ffff88023fc80000(0000) knlGS:0000000000000000
Sep 16 20:21:34 Lilith kernel: CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
Sep 16 20:21:34 Lilith kernel: CR2: 0000000000000334 CR3: 000000013d7d7000 CR4: 00000000000006e0
Sep 16 20:21:34 Lilith kernel: Stack:
Sep 16 20:21:34 Lilith kernel: ffff88018a057e58 ffffffff8126f90f 0000000000001000 ffff880201a02840
Sep 16 20:21:34 Lilith kernel: 0000000000000fff 0000000000000000 ffff880000000055 ffff880000000204
Sep 16 20:21:34 Lilith kernel: 0000000000000001 0000000000000000 ffffea0005796b00 00000000da3419dd
Sep 16 20:21:34 Lilith kernel: Call Trace:
Sep 16 20:21:34 Lilith kernel: [<ffffffff8126f90f>] ? security_mmap_file+0x5f/0xe0
Sep 16 20:21:34 Lilith kernel: [<ffffffff81201e2b>] vfs_fsync_range+0x4b/0xb0
Sep 16 20:21:34 Lilith kernel: [<ffffffff8119326e>] SyS_msync+0x17e/0x1f0
Sep 16 20:21:34 Lilith kernel: [<ffffffff81570a6e>] entry_SYSCALL_64_fastpath+0x12/0x71
Sep 16 20:21:34 Lilith kernel: Code: eb 8e e8 f5 a0 b9 e0 eb 87 48 8b 45 90 4c 8b 75 98 4d 8d a5 a8 00 00 00 4c 89 e7 4c 29 f0 48 83 c0 01 48 89 45 80 e8 6d 59 10 e1 <f0> 41 ff 87 34 03 00 0
Sep 16 20:21:34 Lilith kernel: RIP [<ffffffffa0468f43>] btrfs_sync_file+0xe3/0x380 [btrfs]
Sep 16 20:21:34 Lilith kernel: RSP <ffff88018a057e08>
Sep 16 20:21:34 Lilith kernel: CR2: 0000000000000334
Sep 16 20:21:34 Lilith kernel: ---[ end trace 6f6b5de737c62bb0 ]---