kernel BUG in add_to_swap (2)

Status: upstream: reported on 2026/08/11 00:58
Reported-by: syzbot+6df539bcb1c18bdf732e@syzkaller.appspotmail.com
First crash: 24d, last: 9d06h
Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream kernel BUG in add_to_swap mm -1 7 829d 990d 0/29 auto-obsoleted due to no activity on 2024/09/04 20:46
linux-5.15 kernel BUG in add_to_swap -1 3 898d 981d 0/3 auto-obsoleted due to no activity on 2024/06/28 00:38
linux-6.1 kernel BUG in add_to_swap -1 2 911d 967d 0/3 auto-obsoleted due to no activity on 2024/06/14 15:58

Sample crash report:
raw: 05ffc00000480009 dead000000000100 dead000000000122 ffff0000d59f8cc1
raw: 0000000000020276 0000000000000000 00000002ffffffff ffff0000f82a0000
page dumped because: VM_BUG_ON_FOLIO(!folio_test_uptodate(folio))
------------[ cut here ]------------
kernel BUG at mm/swap_state.c:180!
Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 PID: 12913 Comm: syz.6.2580 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/07/2026
pstate: 82400005 (Nzcv daif +PAN -UAO +TCO -DIT -SSBS BTYPE=--)
pc : add_to_swap+0x1b4/0x1b8 mm/swap_state.c:180
lr : add_to_swap+0x1b4/0x1b8 mm/swap_state.c:180
sp : ffff8000219e6960
x29: ffff8000219e6960 x28: ffff8000219e6b00 x27: dfff800000000000
x26: ffff8000219e6fc0 x25: fffffc0003e82b80 x24: 05ffc00000480009
x23: 1fffff80007d0570 x22: 1fffff80007d0571 x21: dead000000000100
x20: 05ffc00000480009 x19: fffffc0003e82b80 x18: 0000000000000000
x17: 296f696c6f662865 x16: ffff8000082dd25c x15: 747365745f6f696c
x14: 0000000000000001 x13: 1ffff0000433cc70 x12: 0000000000080000
x11: 000000000001f4eb x10: ffff80002346a000 x9 : ffff8000087c9f5c
x8 : 000000000001f4ec x7 : 0000000000000001 x6 : 0000000000000001
x5 : ffff8000219e6398 x4 : ffff800015474e80 x3 : ffff80000831d368
x2 : 0000000000000001 x1 : 0000000100000000 x0 : 0000000000000041
Call trace:
 add_to_swap+0x1b4/0x1b8 mm/swap_state.c:180
 shrink_folio_list+0x1da8/0x4528 mm/vmscan.c:1845
 evict_folios+0x338c/0x4850 mm/vmscan.c:5053
 lru_gen_shrink_lruvec mm/vmscan.c:5236 [inline]
 shrink_lruvec+0x9fc/0x36a4 mm/vmscan.c:5931
 shrink_node_memcgs mm/vmscan.c:6152 [inline]
 shrink_node+0x4c0/0x20bc mm/vmscan.c:6183
 shrink_zones mm/vmscan.c:6424 [inline]
 do_try_to_free_pages+0x55c/0x1470 mm/vmscan.c:6486
 try_to_free_mem_cgroup_pages+0x2f4/0xa8c mm/vmscan.c:6801
 mem_cgroup_resize_max+0x250/0x2e4 mm/memcontrol.c:3506
 mem_cgroup_write+0x1f4/0x224 mm/memcontrol.c:-1
 cgroup_file_write+0x258/0x584 kernel/cgroup/cgroup.c:4101
 kernfs_fop_write_iter+0x390/0x4b4 fs/kernfs/file.c:352
 call_write_iter include/linux/fs.h:2271 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x3c8/0x7c8 fs/read_write.c:584
 ksys_write+0x12c/0x228 fs/read_write.c:637
 __do_sys_write fs/read_write.c:649 [inline]
 __se_sys_write fs/read_write.c:646 [inline]
 __arm64_sys_write+0x7c/0x90 fs/read_write.c:646
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x290 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x13c/0x258 arch/arm64/kernel/syscall.c:140
 do_el0_svc+0x5c/0x134 arch/arm64/kernel/syscall.c:204
 el0_svc+0x58/0x128 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585
Code: f004a8e1 91070021 aa1303e0 97fd393a (d4210000) 
---[ end trace 0000000000000000 ]---

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/08/26 07:55 linux-6.1.y 05208478041c 6a91adb4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 kernel BUG in add_to_swap
2026/08/11 00:57 linux-6.1.y e4f7d8be268e 508909ea .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 kernel BUG in add_to_swap
* Struck through repros no longer work on HEAD.