syzbot


BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio (4)

Status: upstream: reported C repro on 2024/11/16 23:40
Subsystems: fs
[Documentation on labels]
Reported-by: syzbot+09b7d050e4806540153d@syzkaller.appspotmail.com
First crash: 208d, last: 5h27m
Cause bisection: introduced by (bisect log) :
commit ad41251c290dfe3c01472c94d2439a59de23fe97
Author: Andrii Nakryiko <andrii@kernel.org>
Date: Thu Aug 29 17:42:28 2024 +0000

  lib/buildid: implement sleepable build_id_parse() API

Crash: BUG: unable to handle kernel paging request in workingset_refault (log)
Repro: C syz .config
  
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [fs?] BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio (4) 1 (4) 2025/04/06 23:09
Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio (3) erofs C 492 208d 265d 28/28 fixed on 2024/11/12 23:31
upstream BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio fs mm 8 953d 962d 0/28 auto-obsoleted due to no activity on 2023/02/26 19:26
upstream BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio (2) fs 6 727d 777d 0/28 auto-obsoleted due to no activity on 2023/09/20 22:50
Last patch testing requests (1)
Created Duration User Patch Repo Result
2024/11/17 00:18 17m hdanton@sina.com patch upstream OK log

Sample crash report:
BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor instruction fetch in kernel mode
#PF: error_code(0x0010) - not-present page
PGD 0 P4D 0 
Oops: Oops: 0010 [#1] SMP KASAN PTI
CPU: 0 UID: 0 PID: 6539 Comm: syz-executor306 Not tainted 6.15.0-rc5-syzkaller-00207-g1a33418a69cc #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:0x0
Code: Unable to access opcode bytes at 0xffffffffffffffd6.
RSP: 0018:ffffc90004a7f9c8 EFLAGS: 00010293
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff81f1092e
RDX: ffff88806aa00000 RSI: ffffea0001e1b1c0 RDI: ffff888031e936c0
RBP: ffffea0001e1b1c0 R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: 1ffff9200094ff3a
R13: ffff888031e936c0 R14: 0000000000000000 R15: dffffc0000000000
FS:  00007f7731a8a6c0(0000) GS:ffff8881249ec000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 0000000012968000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 filemap_read_folio+0xc5/0x2a0 mm/filemap.c:2401
 do_read_cache_folio+0x263/0x5c0 mm/filemap.c:3885
 freader_get_folio+0x337/0x8e0 lib/buildid.c:77
 freader_fetch+0xc2/0x5e0 lib/buildid.c:120
 __build_id_parse.isra.0+0xec/0x7a0 lib/buildid.c:305
 do_procmap_query+0xd96/0x1090 fs/proc/task_mmu.c:534
 procfs_procmap_ioctl+0x7d/0xb0 fs/proc/task_mmu.c:613
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:906 [inline]
 __se_sys_ioctl fs/ioctl.c:892 [inline]
 __x64_sys_ioctl+0x190/0x200 fs/ioctl.c:892
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x230 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7731af3909
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 18 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f7731a8a218 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f7731b7e3d8 RCX: 00007f7731af3909
RDX: 0000200000000080 RSI: 00000000c0686611 RDI: 0000000000000003
RBP: 00007f7731b7e3d0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f7731b4b400
R13: 0000080000000007 R14: 00002000000000a0 R15: 0000200000000080
 </TASK>
Modules linked in:
CR2: 0000000000000000
---[ end trace 0000000000000000 ]---
RIP: 0010:0x0
Code: Unable to access opcode bytes at 0xffffffffffffffd6.
RSP: 0018:ffffc90004a7f9c8 EFLAGS: 00010293
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff81f1092e
RDX: ffff88806aa00000 RSI: ffffea0001e1b1c0 RDI: ffff888031e936c0
RBP: ffffea0001e1b1c0 R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: 1ffff9200094ff3a
R13: ffff888031e936c0 R14: 0000000000000000 R15: dffffc0000000000
FS:  00007f7731a8a6c0(0000) GS:ffff8881249ec000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 0000000012968000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Crashes (2483):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/05/10 19:37 upstream 1a33418a69cc 77908e5f .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/04/25 06:28 upstream e72e9e693307 e3715315 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/04/25 05:40 upstream e72e9e693307 e3715315 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/04/25 04:53 upstream e72e9e693307 e3715315 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/04/25 04:05 upstream e72e9e693307 e3715315 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/04/04 11:13 upstream a2cc6ff5ec8f d7ae3a11 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/01/02 11:29 upstream 56e6a3499e14 d3ccff63 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2024/12/26 20:28 upstream 9b2ffa6148b1 d3ccff63 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2024/12/26 06:49 upstream 9b2ffa6148b1 444551c4 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2024/12/24 12:38 upstream f07044dd0df0 444551c4 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2024/12/23 04:24 upstream bcde95ce32b6 b4fbdbd4 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2024/12/20 19:09 upstream 8faabc041a00 49cfeac8 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2024/12/20 18:12 upstream 8faabc041a00 49cfeac8 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2024/12/18 12:32 upstream aef25be35d23 a0626d3a .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2024/12/18 12:09 upstream aef25be35d23 a0626d3a .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2024/12/18 11:44 upstream aef25be35d23 a0626d3a .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2024/12/18 11:17 upstream aef25be35d23 a0626d3a .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/03/26 19:25 upstream 1e26c5e28ca5 19e40f48 .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/02/13 14:29 upstream 4dc1d1bec898 7320a65f .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2024/11/13 00:01 upstream 3022e9d00ebe c819f227 .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/01/03 18:03 upstream 0bc21e701a6f 96d578a3 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/06/09 05:05 upstream 939f15e640f1 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/06/08 17:07 upstream 8630c59e9936 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/06/08 09:46 upstream 8630c59e9936 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/06/08 06:10 upstream 8630c59e9936 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/06/08 04:53 upstream 8630c59e9936 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/06/07 23:05 upstream 5b032cac6225 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/06/07 06:36 upstream c0c9379f235d 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/06/06 19:09 upstream e271ed52b344 3d899f2c .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/06/06 15:58 upstream e271ed52b344 3d899f2c .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/06/05 17:45 upstream ec7714e49479 6b6b5f21 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/06/05 16:12 upstream ec7714e49479 6b6b5f21 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/06/04 16:45 upstream 5abc7438f1e9 e565f08d .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/06/03 20:21 upstream 546b1c9e93c2 a30356b7 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/06/02 18:25 upstream cd2e103d57e5 aaaaf5ea .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/06/01 22:04 upstream 7d4e49a77d99 3d2f584d .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/02/25 14:59 upstream d082ecbc71e9 d34966d1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/02/20 19:30 upstream 87a132e73910 50668798 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/05/16 10:23 upstream fee3e843b309 cfde8269 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/06/08 22:34 upstream 939f15e640f1 4826c28e .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/06/08 19:01 upstream 8630c59e9936 4826c28e .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/06/08 12:56 upstream 8630c59e9936 4826c28e .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/06/08 07:16 upstream 8630c59e9936 4826c28e .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/06/07 19:48 upstream bdc7f8c5adad 4826c28e .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/06/07 08:48 upstream c0c9379f235d 4826c28e .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/06/07 02:19 upstream c0c9379f235d 4826c28e .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/06/07 00:09 upstream c0c9379f235d 4826c28e .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/06/06 13:14 upstream e271ed52b344 3d899f2c .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/06/06 05:23 upstream e271ed52b344 6b6b5f21 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/06/06 02:12 upstream e271ed52b344 6b6b5f21 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/06/05 20:16 upstream ec7714e49479 6b6b5f21 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/06/05 08:07 upstream 1af80d00e1e0 6b6b5f21 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/06/05 06:07 upstream 1af80d00e1e0 6b6b5f21 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/06/05 00:50 upstream 1af80d00e1e0 6b6b5f21 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/06/04 20:12 upstream 1af80d00e1e0 e565f08d .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/06/04 14:53 upstream 5abc7438f1e9 e565f08d .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/06/04 13:32 upstream 5abc7438f1e9 e565f08d .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/06/04 11:37 upstream 5abc7438f1e9 e565f08d .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/06/04 04:03 upstream 5abc7438f1e9 a30356b7 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/06/03 23:24 upstream 546b1c9e93c2 a30356b7 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/06/03 15:28 upstream 546b1c9e93c2 a30356b7 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/06/03 09:34 upstream 7f9039c524a3 a30356b7 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/06/03 08:01 upstream 7f9039c524a3 a30356b7 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/06/03 04:02 upstream 7f9039c524a3 a30356b7 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/06/03 01:50 upstream 7f9039c524a3 a30356b7 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/06/03 00:30 upstream 7f9039c524a3 a30356b7 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/06/02 14:09 upstream cd2e103d57e5 aaaaf5ea .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/06/02 07:14 upstream cd2e103d57e5 3d2f584d .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/06/01 20:35 upstream 7d4e49a77d99 3d2f584d .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/05/25 06:42 upstream d0c22de9995b ed351ea7 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/03/14 19:42 upstream e3a854b577cb e2826670 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
2025/06/08 11:21 linux-next 475c850a7fdd 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
* Struck through repros no longer work on HEAD.