syzbot


WARNING in iopt_map_pages (3)

Status: fixed on 2026/01/21 09:45
Subsystems: iommu
[Documentation on labels]
Reported-by: syzbot+57fdb0cf6a0c5d1f15a2@syzkaller.appspotmail.com
Fix commit: e6a973af1113 iommufd/selftest: Check for overflow in IOMMU_TEST_OP_ADD_RESERVED
First crash: 47d, last: 40d
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [iommu?] WARNING in iopt_map_pages (3) 2 (3) 2025/12/12 06:56
Similar bugs (2)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream WARNING in iopt_map_pages (2) iommu -1 C 4 199d 212d 29/29 fixed on 2025/09/04 16:57
upstream WARNING in iopt_map_pages iommu -1 C error 3 511d 592d 28/29 fixed on 2024/10/22 11:56

Sample crash report:
iommufd_mock iommufd_mock0: Adding to iommu group 0
------------[ cut here ]------------
WARNING: CPU: 0 PID: 6739 at drivers/iommu/iommufd/io_pagetable.c:292 iopt_alloc_area_pages drivers/iommu/iommufd/io_pagetable.c:292 [inline]
WARNING: CPU: 0 PID: 6739 at drivers/iommu/iommufd/io_pagetable.c:292 iopt_map_pages+0xd7c/0xdcc drivers/iommu/iommufd/io_pagetable.c:376
Modules linked in:
CPU: 0 UID: 0 PID: 6739 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/03/2025
pstate: 83400005 (Nzcv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--)
pc : iopt_alloc_area_pages drivers/iommu/iommufd/io_pagetable.c:292 [inline]
pc : iopt_map_pages+0xd7c/0xdcc drivers/iommu/iommufd/io_pagetable.c:376
lr : iopt_alloc_area_pages drivers/iommu/iommufd/io_pagetable.c:292 [inline]
lr : iopt_map_pages+0xd7c/0xdcc drivers/iommu/iommufd/io_pagetable.c:376
sp : ffff8000a04f76c0
x29: ffff8000a04f78a0 x28: ffff0000d66f4810 x27: 1fffe0001acde944
x26: ffff8000a04f7b00 x25: 0000000000002fff x24: 0000000000003000
x23: ffff0000d66f4a20 x22: ffff0000d66f49f8 x21: 00000000ffffffea
x20: dfff800000000000 x19: ffff8000a04f79b0 x18: 0000000000000000
x17: ffff800083ce6110 x16: ffff80008052b3c8 x15: 0000000000000007
x14: 0000000000000000 x13: 00000000ffffffff x12: 0000000000ff0100
x11: ffff0000c72f5c40 x10: 0000000000ff0100 x9 : 0000000000000000
x8 : ffff0000c72f5c40 x7 : 0000000000000000 x6 : 000000000000003f
x5 : 0000000000000040 x4 : ffffffffffffefff x3 : ffffffffffffefff
x2 : 0000000000f03fff x1 : 00000000ffffffea x0 : 0000000000000000
Call trace:
 iopt_alloc_area_pages drivers/iommu/iommufd/io_pagetable.c:292 [inline] (P)
 iopt_map_pages+0xd7c/0xdcc drivers/iommu/iommufd/io_pagetable.c:376 (P)
 iopt_map_common+0x204/0x420 drivers/iommu/iommufd/io_pagetable.c:420
 iopt_map_user_pages+0xb4/0xd8 drivers/iommu/iommufd/io_pagetable.c:461
 iommufd_ioas_map+0x2d4/0x3d0 drivers/iommu/iommufd/ioas.c:276
 iommufd_fops_ioctl+0x424/0x54c drivers/iommu/iommufd/main.c:533
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl fs/ioctl.c:583 [inline]
 __arm64_sys_ioctl+0x14c/0x1c4 fs/ioctl.c:583
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x98/0x254 arch/arm64/kernel/syscall.c:49
 el0_svc_common+0xe8/0x23c arch/arm64/kernel/syscall.c:132
 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
 el0_svc+0x5c/0x254 arch/arm64/kernel/entry-common.c:724
 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:743
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596
irq event stamp: 1160
hardirqs last  enabled at (1159): [<ffff80008ae21fa0>] __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:151 [inline]
hardirqs last  enabled at (1159): [<ffff80008ae21fa0>] _raw_spin_unlock_irqrestore+0x38/0x98 kernel/locking/spinlock.c:194
hardirqs last disabled at (1160): [<ffff80008adf99f4>] el1_brk64+0x20/0x54 arch/arm64/kernel/entry-common.c:412
softirqs last  enabled at (132): [<ffff8000801f96d0>] local_bh_enable+0x10/0x34 include/linux/bottom_half.h:32
softirqs last disabled at (130): [<ffff8000801f969c>] local_bh_disable+0x10/0x34 include/linux/bottom_half.h:19
---[ end trace 0000000000000000 ]---

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/12/07 00:31 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 05c93f3395ed d6526ea3 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in iopt_map_pages
2025/12/06 23:53 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 05c93f3395ed d6526ea3 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in iopt_map_pages
2025/12/13 15:23 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 05c93f3395ed d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in iopt_map_pages
2025/12/06 23:20 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 05c93f3395ed d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in iopt_map_pages
* Struck through repros no longer work on HEAD.