syzbot
WARNING in __ioremap_caller
Status:
upstream: reported C repro on 2026/02/22 11:33
Subsystems:
kernel
Labels:
prio:high
[Documentation on labels]
Reported-by: syzbot+49b1021becba70c1f3f6@syzkaller.appspotmail.com
First crash: 200d, last: 1d14h
Sample crash report:
------------[ cut here ]------------
ioremap on RAM at 0x000000001bf67000 - 0x000000001bf67fff
WARNING: arch/x86/mm/ioremap.c:216 at __ioremap_caller.isra.0+0x4c2/0x5f0 arch/x86/mm/ioremap.c:216, CPU#2: syz.0.17/5915
Modules linked in:
CPU: 2 UID: 0 PID: 5915 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:__ioremap_caller.isra.0+0x4d3/0x5f0 arch/x86/mm/ioremap.c:216
Code: 41 5c 41 5d 41 5e 41 5f c3 cc cc cc cc e8 45 cb 50 00 48 8d 3d 2e 85 8d 0f 48 8d 84 24 c0 00 00 00 48 8d 54 24 60 48 8d 70 c0 <67> 48 0f b9 3a eb 89 41 83 ff 04 75 32 e8 1b cb 50 00 bf 04 00 00
RSP: 0018:ffffc900036478a0 EFLAGS: 00010293
RAX: ffffc90003647960 RBX: 1ffff920006c8f18 RCX: 0000000000000000
RDX: ffffc90003647900 RSI: ffffc90003647920 RDI: ffffffff9147f620
RBP: 0000000000001000 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000001
R13: 000000001bf67000 R14: 0000000000000002 R15: 000000001bf67000
FS: 0000000000000000(0000) GS:ffff888096b64000(0063) knlGS:0000000056c88480
CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 0000000000000018 CR3: 000000005eb62000 CR4: 0000000000352ef0
Call Trace:
<TASK>
generic_access_phys+0x130/0x4d0 mm/memory.c:7178
kernfs_vma_access+0x1ce/0x280 fs/kernfs/file.c:437
__access_remote_vm+0x58f/0x890 mm/memory.c:7256
mem_rw+0x2a1/0x670 fs/proc/base.c:912
do_loop_readv_writev fs/read_write.c:848 [inline]
do_loop_readv_writev fs/read_write.c:836 [inline]
vfs_readv+0x5d8/0x8d0 fs/read_write.c:1021
do_readv+0x13e/0x340 fs/read_write.c:1081
do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:79 [inline]
__do_fast_syscall_32+0x13a/0x8b0 arch/x86/entry/syscall_32.c:291
do_fast_syscall_32+0x32/0x70 arch/x86/entry/syscall_32.c:316
entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf7f14fec
Code: Unable to access opcode bytes at 0xf7f14fc2.
RSP: 002b:00000000ffc02c5c EFLAGS: 00000296 ORIG_RAX: 0000000000000091
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000080000100
RDX: 0000000000000002 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
</TASK>
----------------
Code disassembly (best guess):
0: 41 5c pop %r12
2: 41 5d pop %r13
4: 41 5e pop %r14
6: 41 5f pop %r15
8: c3 ret
9: cc int3
a: cc int3
b: cc int3
c: cc int3
d: e8 45 cb 50 00 call 0x50cb57
12: 48 8d 3d 2e 85 8d 0f lea 0xf8d852e(%rip),%rdi # 0xf8d8547
19: 48 8d 84 24 c0 00 00 lea 0xc0(%rsp),%rax
20: 00
21: 48 8d 54 24 60 lea 0x60(%rsp),%rdx
26: 48 8d 70 c0 lea -0x40(%rax),%rsi
* 2a: 67 48 0f b9 3a ud1 (%edx),%rdi <-- trapping instruction
2f: eb 89 jmp 0xffffffba
31: 41 83 ff 04 cmp $0x4,%r15d
35: 75 32 jne 0x69
37: e8 1b cb 50 00 call 0x50cb57
3c: bf .byte 0xbf
3d: 04 00 add $0x0,%al
* Struck through repros no longer work on HEAD.