Re: [PATCH] fuse: when copying a folio delay the mark dirty until the end

From: kernel test robot

Date: Thu Mar 26 2026 - 02:41:42 EST

Hello,

kernel test robot noticed "RIP:fuse_iomap_writeback_range[fuse]" on:

commit: 47f8dde97f35e32a1003d54e387273bcdf014ddf ("[PATCH] fuse: when copying a folio delay the mark dirty until the end")
url: https://github.com/intel-lab-lkp/linux/commits/Horst-Birthelmer/fuse-when-copying-a-folio-delay-the-mark-dirty-until-the-end/20260316-234418
patch link: https://lore.kernel.org/all/20260316-mark-dirty-per-folio-v1-1-8dc39c94b7ce@xxxxxxx/
patch subject: [PATCH] fuse: when copying a folio delay the mark dirty until the end

in testcase: ltp
version:
with following parameters:

disk: 1HDD
fs: ext4
test: fs-03

config: x86_64-rhel-9.4-ltp
compiler: gcc-14
test machine: 36 threads 1 sockets Intel(R) Core(TM) i9-10980XE CPU @ 3.00GHz (Cascade Lake) with 128G memory

(please refer to attached dmesg/kmsg for entire log/backtrace)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <oliver.sang@xxxxxxxxx>
| Closes: https://lore.kernel.org/oe-lkp/202603261451.d2a4cd46-lkp@xxxxxxxxx

kern :warn : [ 623.963830] [ T243] ------------[ cut here ]------------
kern :warn : [ 623.964688] [ T243] WARNING: fs/fuse/file.c:2025 at fuse_iomap_writeback_range+0xeb3/0x17b0 [fuse], CPU#24: 9/243
kern :warn : [ 623.966501] [ T243] Modules linked in: exfat vfat fat xfs loop ext4 mbcache jbd2 dm_mod binfmt_misc intel_rapl_msr intel_rapl_common intel_uncore_frequency intel_uncore_frequency_common skx_edac_common nfit libnvdimm amdgpu x86_pkg_temp_thermal intel_powerclamp snd_hda_codec_alc882 snd_hda_codec_realtek_lib snd_hda_codec_atihdmi coretemp snd_hda_codec_generic snd_hda_codec_hdmi btrfs amdxcp snd_soc_avs drm_panel_backlight_quirks sd_mod kvm_intel gpu_sched snd_soc_hda_codec sg libblake2b drm_buddy snd_hda_intel snd_hda_ext_core xor drm_ttm_helper zstd_compress ttm snd_hda_codec kvm drm_exec snd_hda_core drm_suballoc_helper raid6_pq snd_soc_core snd_intel_dspcfg drm_display_helper snd_intel_sdw_acpi irqbypass snd_hwdep snd_compress ghash_clmulni_intel cec snd_pcm rapl ahci drm_client_lib intel_cstate drm_kms_helper snd_timer libahci wmi_bmof mxm_wmi intel_wmi_thunderbolt nvme snd mei_me i2c_i801 video intel_uncore libata nvme_core wdat_wdt soundcore crc16 pcspkr i2c_smbus ioatdma mei dca wmi drm fuse nfnetlink
kern :warn : [ 623.977867] [ T243] CPU: 24 UID: 0 PID: 243 Comm: kworker/u144:9 Tainted: G S 7.0.0-rc4-00001-g47f8dde97f35 #1 PREEMPT(lazy)
kern :warn : [ 623.979856] [ T243] Tainted: [S]=CPU_OUT_OF_SPEC
kern :warn : [ 623.980727] [ T243] Hardware name: Gigabyte Technology Co., Ltd. X299 UD4 Pro/X299 UD4 Pro-CF, BIOS F8a 04/27/2021
kern :warn : [ 623.982101] [ T243] Workqueue: writeback wb_workfn (flush-7:0-fuseblk)
kern :warn : [ 623.983158] [ T243] RIP: 0010:fuse_iomap_writeback_range (fs/fuse/file.c:2025 (discriminator 1) fs/fuse/file.c:2206 (discriminator 1)) fuse
kern :warn : [ 623.984255] [ T243] Code: 03 80 3c 02 00 0f 85 fc 03 00 00 48 8b 44 24 18 49 89 47 08 e9 0e f3 ff ff 0f 0b e9 dd f2 ff ff 48 8b 7c 24 20 e8 4d a0 08 c4 <0f> 0b 48 b8 00 00 00 00 00 fc ff df 4c 89 ea 48 c1 ea 03 80 3c 02
All code
========
0: 03 80 3c 02 00 0f add 0xf00023c(%rax),%eax
6: 85 fc test %edi,%esp
8: 03 00 add (%rax),%eax
a: 00 48 8b add %cl,-0x75(%rax)
d: 44 24 18 rex.R and $0x18,%al
10: 49 89 47 08 mov %rax,0x8(%r15)
14: e9 0e f3 ff ff jmp 0xfffffffffffff327
19: 0f 0b ud2
1b: e9 dd f2 ff ff jmp 0xfffffffffffff2fd
20: 48 8b 7c 24 20 mov 0x20(%rsp),%rdi
25: e8 4d a0 08 c4 call 0xffffffffc408a077
2a:* 0f 0b ud2 <-- trapping instruction
2c: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax
33: fc ff df
36: 4c 89 ea mov %r13,%rdx
39: 48 c1 ea 03 shr $0x3,%rdx
3d: 80 .byte 0x80
3e: 3c 02 cmp $0x2,%al

Code starting with the faulting instruction
===========================================
0: 0f 0b ud2
2: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax
9: fc ff df
c: 4c 89 ea mov %r13,%rdx
f: 48 c1 ea 03 shr $0x3,%rdx
13: 80 .byte 0x80
14: 3c 02 cmp $0x2,%al
kern :warn : [ 623.986908] [ T243] RSP: 0018:ffffc9000131f320 EFLAGS: 00010286
kern :warn : [ 623.987958] [ T243] RAX: ffff888167fd4ea8 RBX: 0000000000000000 RCX: 1ffff1102cffa9d5
kern :warn : [ 623.989181] [ T243] RDX: ffff888167fd4ea8 RSI: 0000000000000004 RDI: ffff888167fd4f28
kern :warn : [ 623.990332] [ T243] RBP: ffff888167fd4c00 R08: 0000000000000001 R09: fffff52000263e59
kern :warn : [ 623.991500] [ T243] R10: 0000000000000003 R11: 0000000000000038 R12: 0000000000000000
kern :warn : [ 623.992678] [ T243] R13: ffffc9000131f590 R14: ffffea000aff1380 R15: ffffc9000131f588
kern :warn : [ 623.993830] [ T243] FS: 0000000000000000(0000) GS:ffff88a09e48c000(0000) knlGS:0000000000000000
kern :warn : [ 623.995069] [ T243] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
kern :warn : [ 623.996117] [ T243] CR2: 00007f8e6b375000 CR3: 000000209ca72001 CR4: 00000000003726f0
kern :warn : [ 623.997263] [ T243] Call Trace:
kern :warn : [ 623.998054] [ T243] <TASK>
kern :warn : [ 623.998796] [ T243] iomap_writeback_folio (fs/iomap/buffered-io.c:1777 fs/iomap/buffered-io.c:1895)
kern :warn : [ 623.999721] [ T243] ? __pfx_iomap_writeback_folio (fs/iomap/buffered-io.c:1854)
kern :warn : [ 624.000685] [ T243] ? writeback_iter (mm/page-writeback.c:2513)
kern :warn : [ 624.001559] [ T243] iomap_writepages (fs/iomap/buffered-io.c:1959)
kern :warn : [ 624.002410] [ T243] ? __pfx_iomap_writepages (fs/iomap/buffered-io.c:1944)
kern :warn : [ 624.003325] [ T243] ? unwind_next_frame (include/linux/rcupdate.h:1193 arch/x86/kernel/unwind_orc.c:495)
kern :warn : [ 624.004213] [ T243] ? ret_from_fork_asm (arch/x86/entry/entry_64.S:255)
kern :warn : [ 624.005068] [ T243] fuse_writepages (fs/fuse/file.c:2276) fuse
kern :warn : [ 624.005975] [ T243] ? __pfx_fuse_writepages (fs/fuse/file.c:2276) fuse
kern :warn : [ 624.006916] [ T243] ? update_sg_lb_stats (kernel/sched/fair.c:10481 (discriminator 2))
kern :warn : [ 624.007771] [ T243] ? __pfx__raw_spin_lock (kernel/locking/spinlock.c:153)
kern :warn : [ 624.008629] [ T243] do_writepages (mm/page-writeback.c:2558)
kern :warn : [ 624.009436] [ T243] __writeback_single_inode (fs/fs-writeback.c:1759)
kern :warn : [ 624.010308] [ T243] writeback_sb_inodes (fs/fs-writeback.c:2045)
kern :warn : [ 624.011156] [ T243] ? __pfx_writeback_sb_inodes (fs/fs-writeback.c:1946)
kern :warn : [ 624.012141] [ T243] ? __wb_calc_thresh (arch/x86/include/asm/atomic64_64.h:15 include/linux/atomic/atomic-arch-fallback.h:2583 include/linux/atomic/atomic-long.h:38 include/linux/atomic/atomic-instrumented.h:3189 mm/page-writeback.c:160 mm/page-writeback.c:912)
kern :warn : [ 624.012991] [ T243] ? __pfx_down_read_trylock (kernel/locking/rwsem.c:1575)
kern :warn : [ 624.013925] [ T243] ? __pfx_move_expired_inodes (fs/fs-writeback.c:1499)
kern :warn : [ 624.014835] [ T243] __writeback_inodes_wb (fs/fs-writeback.c:2119)
kern :warn : [ 624.015718] [ T243] wb_writeback (fs/fs-writeback.c:2229)
kern :warn : [ 624.016519] [ T243] ? __pfx_wb_writeback (fs/fs-writeback.c:2172)
kern :warn : [ 624.017340] [ T243] ? get_nr_dirty_inodes (fs/inode.c:95 (discriminator 1) fs/inode.c:103 (discriminator 1))
kern :warn : [ 624.018188] [ T243] wb_do_writeback (fs/fs-writeback.c:2387 (discriminator 1))
kern :warn : [ 624.018984] [ T243] ? set_worker_desc (kernel/workqueue.c:6209)
kern :warn : [ 624.019821] [ T243] ? __pfx_wb_do_writeback (fs/fs-writeback.c:2367)
kern :warn : [ 624.020682] [ T243] ? finish_task_switch+0x13b/0x6f0
kern :warn : [ 624.021574] [ T243] ? __switch_to (arch/x86/include/asm/cpufeature.h:101 arch/x86/kernel/process_64.c:377 arch/x86/kernel/process_64.c:665)
kern :warn : [ 624.022332] [ T243] wb_workfn (fs/fs-writeback.c:2414)
kern :warn : [ 624.023026] [ T243] process_one_work (arch/x86/include/asm/jump_label.h:37 include/trace/events/workqueue.h:110 kernel/workqueue.c:3281)
kern :warn : [ 624.023772] [ T243] ? assign_work (kernel/workqueue.c:1219)
kern :warn : [ 624.024470] [ T243] worker_thread (kernel/workqueue.c:3353 (discriminator 2) kernel/workqueue.c:3440 (discriminator 2))
kern :warn : [ 624.025199] [ T243] ? __pfx_worker_thread (kernel/workqueue.c:3386)
kern :warn : [ 624.025970] [ T243] kthread (kernel/kthread.c:436)
kern :warn : [ 624.026642] [ T243] ? recalc_sigpending (arch/x86/include/asm/bitops.h:75 include/asm-generic/bitops/instrumented-atomic.h:42 include/linux/thread_info.h:109 kernel/signal.c:181)
kern :warn : [ 624.027381] [ T243] ? __pfx_kthread (kernel/kthread.c:381)
kern :warn : [ 624.028081] [ T243] ret_from_fork (arch/x86/kernel/process.c:164)
kern :warn : [ 624.028770] [ T243] ? __pfx_ret_from_fork (arch/x86/kernel/process.c:153)
kern :warn : [ 624.029533] [ T243] ? switch_fpu (arch/x86/include/asm/bitops.h:202 (discriminator 1) arch/x86/include/asm/bitops.h:232 (discriminator 1) include/asm-generic/bitops/instrumented-non-atomic.h:142 (discriminator 1) include/linux/thread_info.h:133 (discriminator 1) include/linux/sched.h:2064 (discriminator 1) arch/x86/include/asm/fpu/sched.h:34 (discriminator 1))
kern :warn : [ 624.030233] [ T243] ? __switch_to (arch/x86/include/asm/cpufeature.h:101 arch/x86/kernel/process_64.c:377 arch/x86/kernel/process_64.c:665)
kern :warn : [ 624.030868] [ T243] ? __pfx_kthread (kernel/kthread.c:381)
kern :warn : [ 624.031524] [ T243] ret_from_fork_asm (arch/x86/entry/entry_64.S:255)
kern :warn : [ 624.032186] [ T243] </TASK>
kern :warn : [ 624.032704] [ T243] ---[ end trace 0000000000000000 ]---

The kernel config and materials to reproduce are available at:
https://download.01.org/0day-ci/archive/20260326/202603261451.d2a4cd46-lkp@xxxxxxxxx

--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki