md/raid:md0: not clean -- starting background reconstruction
md/raid:md0: device ram0 operational as raid disk 0
md/raid:md0: raid level 5 active with 1 out of 1 devices, algorithm 0
------------[ cut here ]------------
UBSAN: shift-out-of-bounds in ./include/linux/log2.h:57:13
shift exponent 64 is too large for 64-bit type 'unsigned long'
CPU: 0 UID: 0 PID: 5972 Comm: syz.0.19 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 ubsan_epilogue+0xa/0x30 lib/ubsan.c:233
 __ubsan_handle_shift_out_of_bounds+0x36d/0x400 lib/ubsan.c:494
 __roundup_pow_of_two include/linux/log2.h:57 [inline]
 raid5_set_limits+0x538/0x660 drivers/md/raid5.c:7835
 raid5_run+0x1e86/0x2560 drivers/md/raid5.c:8133
 md_run+0xdbd/0x1e00 drivers/md/md.c:6760
 do_md_run+0x35/0x720 drivers/md/md.c:6861
 array_state_store+0x958/0xe90 drivers/md/md.c:-1
 md_attr_store+0x3b7/0x640 drivers/md/md.c:6137
 kernfs_fop_write_iter+0x3a5/0x540 fs/kernfs/file.c:345
 new_sync_write fs/read_write.c:595 [inline]
 vfs_write+0x61e/0xbb0 fs/read_write.c:687
 ksys_write+0x156/0x270 fs/read_write.c:739
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f094044e0d9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffc11fef8d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f09406d5fa0 RCX: 00007f094044e0d9
RDX: 0000000000000006 RSI: 00002000000007c0 RDI: 0000000000000009
RBP: 00007f09404e5024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f09406d5fac R14: 00007f09406d5fa0 R15: 00007f09406d5fa0
 </TASK>
---[ end trace ]---