Re: [syzbot] [io-uring?] [ext4?] INFO: task hung in io_write
From: syzbot
Date: Wed Sep 09 2026 - 07:54:51 EST
Hello,
syzbot tried to test the proposed patch but the build/boot failed:
[ T1] jffs2: version 2.2. (NAND) (SUMMARY) © 2001-2006 Red Hat, Inc.
[ 9.450006][ T1] romfs: ROMFS MTD (C) 2007 Red Hat, Inc.
[ 9.454451][ T1] QNX4 filesystem 0.2.3 registered.
[ 9.467839][ T1] qnx6: QNX6 filesystem 1.0.0 registered.
[ 9.473957][ T1] fuse: init (API version 7.45)
[ 9.493414][ T106] kworker/u4:1 (106) used greatest stack depth: 26960 bytes left
[ 9.499661][ T1] orangefs_debugfs_init: called with debug mask: :none: :0:
[ 9.517806][ T1] orangefs_init: module version upstream loaded
[ 9.523522][ T1] JFS: nTxBlock = 6145, nTxLock = 49167
[ 9.549727][ T1] SGI XFS with ACLs, security attributes, realtime, scrub, repair, quota, no debug enabled
[ 9.587305][ T1] 9p: Installing v9fs 9p2000 file system support
[ 9.598431][ T1] NILFS version 2 loaded
[ 9.601604][ T1] befs: version: 0.9.3
[ 9.605491][ T1] ocfs2: Registered cluster interface o2cb
[ 9.629421][ T1] ocfs2: Registered cluster interface user
[ 9.648529][ T1] OCFS2 User DLM kernel interface loaded
[ 9.683543][ T115] kworker/u4:2 (115) used greatest stack depth: 26504 bytes left
[ 9.711809][ T1] gfs2: GFS2 installed
[ 9.750240][ T1] ceph: loaded (mds proto 32)
[ 9.783162][ T1] NET: Registered PF_ALG protocol family
[ 9.798112][ T1] async_tx: api initialized (async)
[ 9.802397][ T1] Key type asymmetric registered
[ 9.817841][ T1] Asymmetric key parser 'x509' registered
[ 9.822530][ T1] Asymmetric key parser 'pkcs8' registered
[ 9.826906][ T1] Key type pkcs7_test registered
[ 9.839159][ T1] Block layer SCSI generic (bsg) driver version 0.4 loaded (major 239)
[ 9.863479][ T1] io scheduler mq-deadline registered
[ 9.867560][ T1] io scheduler kyber registered
[ 9.878657][ T1] io scheduler bfq registered
[ 9.888919][ T1] raid6: skipped pq benchmark and selected avx512x4
[ 9.992971][ T1] ACPI: \_SB_.GSIE: Enabled at IRQ 20
[ 10.028066][ T1] pcieport 0000:00:04.0: PME: Signaling with IRQ 25
[ 10.059120][ T1] pcieport 0000:00:04.0: AER: enabled with IRQ 26
[ 10.082251][ T1] input: Power Button as /devices/platform/LNXPWRBN:00/input/input0
[ 10.101416][ T1] ACPI: button: Power Button [PWRF]
[ 10.994864][ T1] ioatdma: Intel(R) QuickData Technology Driver 5.00
[ 11.099208][ T1] ACPI: \_SB_.GSIF: Enabled at IRQ 21
[ 11.203563][ T1] ACPI: \_SB_.GSIH: Enabled at IRQ 23
[ 12.461571][ T1] N_HDLC line discipline registered with maxframe=4096
[ 12.473979][ T1] Serial: 8250/16550 driver, 4 ports, IRQ sharing enabled
[ 12.490839][ T1] 00:03: ttyS0 at I/O 0x3f8 (irq = 4, base_baud = 115200) is a 16550A
[ 12.596214][ T1] Non-volatile memory driver v1.3
[ 12.619055][ T1] usbcore: registered new interface driver xillyusb
[ 12.631909][ T1] ACPI: bus type drm_connector registered
[ 12.646781][ T1] [drm] Initialized vgem 1.0.0 for vgem on minor 0
[ 12.653751][ T1] usbcore: registered new interface driver udl
[ 12.660228][ T1] [drm] pci: virtio-vga detected at 0000:00:01.0
[ 12.665091][ T1] virtio-pci 0000:00:01.0: vgaarb: deactivate vga console
[ 12.690228][ T1] Console: switching to colour dummy device 80x25
[ 12.699414][ T1] [drm] features: -virgl +edid -resource_blob -host_visible
[ 12.699488][ T1] [drm] features: -context_init -blob_alignment
[ 12.717375][ T1] [drm] number of scanouts: 1
[ 12.721344][ T1] [drm] number of cap sets: 0
[ 12.728666][ T1] ------------[ cut here ]------------
[ 12.732715][ T1] [PLANE:36:plane-1] pixel format with alpha exposed but blend mode not setup
[ 12.732728][ T1] WARNING: drivers/gpu/drm/drm_mode_config.c:873 at drm_mode_config_validate+0x1c6a/0x1e60, CPU#0: swapper/0/1
[ 12.747874][ T1] Modules linked in:
[ 12.750657][ T1] CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(full)
[ 12.756989][ T1] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
[ 12.764555][ T1] RIP: 0010:drm_mode_config_validate+0x1cab/0x1e60
[ 12.769342][ T1] Code: 0f 85 ae 00 00 00 4d 8d 77 10 8b 6d 00 4c 89 f0 48 c1 e8 03 80 3c 18 00 74 08 4c 89 f7 e8 7d a5 a3 fc 49 8b 16 4c 89 ef 89 ee <67> 48 0f b9 3a eb 05 e8 89 54 32 fc 49 bd 00 00 00 00 00 fc ff df
[ 12.783031][ T1] RSP: 0000:ffffc900001af450 EFLAGS: 00010246
[ 12.787445][ T1] RAX: 1ffff110000a2808 RBX: dffffc0000000000 RCX: ffff88801ceb0000
[ 12.793083][ T1] RDX: ffff88801f5dd780 RSI: 0000000000000024 RDI: ffffffff9085b000
[ 12.798984][ T1] RBP: 0000000000000024 R08: ffffffff8ec2b347 R09: 1ffffffff1d85668
[ 12.804669][ T1] R10: dffffc0000000000 R11: fffffbfff1d85669 R12: dffffc0000000000
[ 12.810525][ T1] R13: ffffffff9085b000 R14: ffff888000514040 R15: ffff888000514030
[ 12.816240][ T1] FS: 0000000000000000(0000) GS:ffff88808c2e6000(0000) knlGS:0000000000000000
[ 12.822827][ T1] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 12.827688][ T1] CR2: ffff88801af19000 CR3: 000000000eb46000 CR4: 0000000000352ef0
[ 12.833506][ T1] Call Trace:
[ 12.835839][ T1] <TASK>
[ 12.838056][ T1] ? __pfx_autoremove_wake_function+0x10/0x10
[ 12.842500][ T1] drm_dev_register+0x7c/0xd80
[ 12.845841][ T1] virtio_gpu_probe+0x1cb/0x290
[ 12.849449][ T1] virtio_dev_probe+0xdf6/0x10c0
[ 12.853176][ T1] ? up_write+0x19d/0x4a0
[ 12.856327][ T1] ? __pfx_virtio_dev_probe+0x10/0x10
[ 12.860356][ T1] ? driver_sysfs_add+0x1fe/0x210
[ 12.864021][ T1] ? __pfx_virtio_dev_probe+0x10/0x10
[ 12.867970][ T1] really_probe+0x254/0xae0
[ 12.871209][ T1] __driver_probe_device+0x1e8/0x360
[ 12.875197][ T1] driver_probe_device+0x4f/0x240
[ 12.878980][ T1] __driver_attach+0x339/0x600
[ 12.882501][ T1] bus_for_each_dev+0x23b/0x2c0
[ 12.886017][ T1] ? __pfx___driver_attach+0x10/0x10
[ 12.889911][ T1] ? __pfx_bus_for_each_dev+0x10/0x10
[ 12.893969][ T1] ? do_raw_spin_unlock+0x4d/0x200
[ 12.897821][ T1] bus_add_driver+0x345/0x670
[ 12.901156][ T1] driver_register+0x23a/0x320
[ 12.904616][ T1] ? __pfx_virtio_gpu_driver_init+0x10/0x10
[ 12.908997][ T1] virtio_gpu_driver_init+0x96/0x110
[ 12.912765][ T1] do_one_initcall+0x250/0x870
[ 12.916048][ T1] ? __pfx_virtio_gpu_driver_init+0x10/0x10
[ 12.920425][ T1] ? __pfx_do_one_initcall+0x10/0x10
[ 12.924224][ T1] ? lapic_next_event+0x11/0x20
[ 12.927996][ T1] ? clockevents_program_event+0x491/0x630
[ 12.932173][ T1] ? __pfx___schedule+0x10/0x10
[ 12.935834][ T1] ? irqentry_exit+0x218/0x910
[ 12.939393][ T1] ? lockdep_hardirqs_on+0x7b/0x110
[ 12.943214][ T1] ? irqentry_exit+0x218/0x910
[ 12.946613][ T1] ? trace_irq_disable+0x3b/0x140
[ 12.950297][ T1] ? strlen+0x2e/0x70
[ 12.953299][ T1] ? next_arg+0x4a0/0x5e0
[ 12.956477][ T1] ? parameq+0x14d/0x170
[ 12.959569][ T1] ? parse_args+0x9c3/0xad0
[ 12.962839][ T1] ? rcu_is_watching+0x16/0xb0
[ 12.966030][ T1] do_initcall_level+0x10a/0x1a0
[ 12.969717][ T1] ? kernel_init+0x22/0x1d0
[ 12.973025][ T1] do_initcalls+0x59/0xa0
[ 12.976142][ T1] kernel_init_freeable+0x29d/0x3e0
[ 12.980086][ T1] ? __pfx_kernel_init+0x10/0x10
[ 12.983647][ T1] kernel_init+0x22/0x1d0
[ 12.986760][ T1] ? __pfx_kernel_init+0x10/0x10
[ 12.990406][ T1] ret_from_fork+0x514/0xb70
[ 12.993692][ T1] ? __pfx_ret_from_fork+0x10/0x10
[ 12.997415][ T1] ? __switch_to+0xc89/0x1420
[ 13.000914][ T1] ? __pfx_kernel_init+0x10/0x10
[ 13.004417][ T1] ret_from_fork_asm+0x1a/0x30
[ 13.007943][ T1] </TASK>
[ 13.010159][ T1] Kernel panic - not syncing: kernel: panic_on_warn set ...
[ 13.015418][ T1] CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(full)
[ 13.017889][ T1] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
[ 13.017889][ T1] Call Trace:
[ 13.017889][ T1] <TASK>
[ 13.017889][ T1] vpanic+0x56d/0xa60
[ 13.017889][ T1] ? __pfx__printk+0x10/0x10
[ 13.017889][ T1] ? __pfx_vpanic+0x10/0x10
[ 13.017889][ T1] ? is_bpf_text_address+0x292/0x2b0
[ 13.017889][ T1] ? is_bpf_text_address+0x26/0x2b0
[ 13.017889][ T1] panic+0xc5/0xd0
[ 13.017889][ T1] ? __pfx_panic+0x10/0x10
[ 13.017889][ T1] ? ret_from_fork_asm+0x1a/0x30
[ 13.017889][ T1] __warn+0x315/0x4c0
[ 13.017889][ T1] ? drm_mode_config_validate+0x1c6a/0x1e60
[ 13.017889][ T1] ? drm_mode_config_validate+0x1c6a/0x1e60
[ 13.017889][ T1] __report_bug+0x276/0x570
[ 13.017889][ T1] ? blocking_notifier_chain_register+0x50/0xc0
[ 13.017889][ T1] ? drm_mode_config_validate+0x1c6a/0x1e60
[ 13.017889][ T1] ? __pfx___report_bug+0x10/0x10
[ 13.017889][ T1] ? blocking_notifier_chain_register+0x6b/0xc0
[ 13.017889][ T1] report_bug_entry+0x19b/0x290
[ 13.017889][ T1] ? drm_mode_config_validate+0x1cab/0x1e60
[ 13.017889][ T1] ? drm_mode_config_validate+0x1cb0/0x1e60
[ 13.017889][ T1] handle_bug+0xce/0x200
[ 13.017889][ T1] exc_invalid_op+0x1a/0x50
[ 13.017889][ T1] asm_exc_invalid_op+0x1a/0x20
[ 13.017889][ T1] RIP: 0010:drm_mode_config_validate+0x1cab/0x1e60
[ 13.017889][ T1] Code: 0f 85 ae 00 00 00 4d 8d 77 10 8b 6d 00 4c 89 f0 48 c1 e8 03 80 3c 18 00 74 08 4c 89 f7 e8 7d a5 a3 fc 49 8b 16 4c 89 ef 89 ee <67> 48 0f b9 3a eb 05 e8 89 54 32 fc 49 bd 00 00 00 00 00 fc ff df
[ 13.017889][ T1] RSP: 0000:ffffc900001af450 EFLAGS: 00010246
[ 13.017889][ T1] RAX: 1ffff110000a2808 RBX: dffffc0000000000 RCX: ffff88801ceb0000
[ 13.017889][ T1] RDX: ffff88801f5dd780 RSI: 0000000000000024 RDI: ffffffff9085b000
[ 13.017889][ T1] RBP: 0000000000000024 R08: ffffffff8ec2b347 R09: 1ffffffff1d85668
[ 13.017889][ T1] R10: dffffc0000000000 R11: fffffbfff1d85669 R12: dffffc0000000000
[ 13.017889][ T1] R13: ffffffff9085b000 R14: ffff888000514040 R15: ffff888000514030
[ 13.017889][ T1] ? __pfx_autoremove_wake_function+0x10/0x10
[ 13.017889][ T1] drm_dev_register+0x7c/0xd80
[ 13.017889][ T1] virtio_gpu_probe+0x1cb/0x290
[ 13.017889][ T1] virtio_dev_probe+0xdf6/0x10c0
[ 13.017889][ T1] ? up_write+0x19d/0x4a0
[ 13.017889][ T1] ? __pfx_virtio_dev_probe+0x10/0x10
[ 13.017889][ T1] ? driver_sysfs_add+0x1fe/0x210
[ 13.017889][ T1] ? __pfx_virtio_dev_probe+0x10/0x10
[ 13.017889][ T1] really_probe+0x254/0xae0
[ 13.017889][ T1] __driver_probe_device+0x1e8/0x360
[ 13.017889][ T1] driver_probe_device+0x4f/0x240
[ 13.017889][ T1] __driver_attach+0x339/0x600
[ 13.017889][ T1] bus_for_each_dev+0x23b/0x2c0
[ 13.017889][ T1] ? __pfx___driver_attach+0x10/0x10
[ 13.017889][ T1] ? __pfx_bus_for_each_dev+0x10/0x10
[ 13.017889][ T1] ? do_raw_spin_unlock+0x4d/0x200
[ 13.017889][ T1] bus_add_driver+0x345/0x670
[ 13.017889][ T1] driver_register+0x23a/0x320
[ 13.017889][ T1] ? __pfx_virtio_gpu_driver_init+0x10/0x10
[ 13.017889][ T1] virtio_gpu_driver_init+0x96/0x110
[ 13.017889][ T1] do_one_initcall+0x250/0x870
[ 13.017889][ T1] ? __pfx_virtio_gpu_driver_init+0x10/0x10
[ 13.017889][ T1] ? __pfx_do_one_initcall+0x10/0x10
[ 13.017889][ T1] ? lapic_next_event+0x11/0x20
[ 13.017889][ T1] ? clockevents_program_event+0x491/0x630
[ 13.017889][ T1] ? __pfx___schedule+0x10/0x10
[ 13.017889][ T1] ? irqentry_exit+0x218/0x910
[ 13.017889][ T1] ? lockdep_hardirqs_on+0x7b/0x110
[ 13.017889][ T1] ? irqentry_exit+0x218/0x910
[ 13.017889][ T1] ? trace_irq_disable+0x3b/0x140
[ 13.017889][ T1] ? strlen+0x2e/0x70
[ 13.017889][ T1] ? next_arg+0x4a0/0x5e0
[ 13.017889][ T1] ? parameq+0x14d/0x170
[ 13.017889][ T1] ? parse_args+0x9c3/0xad0
[ 13.017889][ T1] ? rcu_is_watching+0x16/0xb0
[ 13.017889][ T1] do_initcall_level+0x10a/0x1a0
[ 13.017889][ T1] ? kernel_init+0x22/0x1d0
[ 13.017889][ T1] do_initcalls+0x59/0xa0
[ 13.017889][ T1] kernel_init_freeable+0x29d/0x3e0
[ 13.017889][ T1] ? __pfx_kernel_init+0x10/0x10
[ 13.017889][ T1] kernel_init+0x22/0x1d0
[ 13.017889][ T1] ? __pfx_kernel_init+0x10/0x10
[ 13.017889][ T1] ret_from_fork+0x514/0xb70
[ 13.017889][ T1] ? __pfx_ret_from_fork+0x10/0x10
[ 13.017889][ T1] ? __switch_to+0xc89/0x1420
[ 13.017889][ T1] ? __pfx_kernel_init+0x10/0x10
[ 13.017889][ T1] ret_from_fork_asm+0x1a/0x30
[ 13.017889][ T1] </TASK>
[ 13.017889][ T1] Kernel Offset: disabled
[ 13.017889][ T1] Rebooting in 86400 seconds..
syzkaller build log:
go env (err=<nil>)
AR='ar'
CC='gcc'
CGO_CFLAGS='-O2 -g'
CGO_CPPFLAGS=''
CGO_CXXFLAGS='-O2 -g'
CGO_ENABLED='1'
CGO_FFLAGS='-O2 -g'
CGO_LDFLAGS='-O2 -g'
CXX='g++'
GCCGO='gccgo'
GO111MODULE='auto'
GOAMD64='v1'
GOARCH='amd64'
GOAUTH='netrc'
GOBIN=''
GOCACHE='/syzkaller/.cache/go-build'
GOCACHEPROG=''
GODEBUG=''
GOENV='/syzkaller/.config/go/env'
GOEXE=''
GOEXPERIMENT=''
GOFIPS140='off'
GOFLAGS=''
GOGCCFLAGS='-fPIC -m64 -pthread -Wl,--no-gc-sections -fmessage-length=0 -ffile-prefix-map=/tmp/go-build2768744602=/tmp/go-build -gno-record-gcc-switches'
GOHOSTARCH='amd64'
GOHOSTOS='linux'
GOINSECURE=''
GOMOD='/syzkaller/jobs/linux/gopath/src/github.com/google/syzkaller/go.mod'
GOMODCACHE='/syzkaller/jobs/linux/gopath/pkg/mod'
GONOPROXY=''
GONOSUMDB=''
GOOS='linux'
GOPATH='/syzkaller/jobs/linux/gopath'
GOPRIVATE=''
GOPROXY='https://proxy.golang.org,direct'
GOROOT='/usr/local/go'
GOSUMDB='sum.golang.org'
GOTELEMETRY='local'
GOTELEMETRYDIR='/syzkaller/.config/go/telemetry'
GOTMPDIR=''
GOTOOLCHAIN='auto'
GOTOOLDIR='/usr/local/go/pkg/tool/linux_amd64'
GOVCS=''
GOVERSION='go1.26.0'
GOWORK=''
PKG_CONFIG='pkg-config'
git status (err=<nil>)
HEAD detached at 680aa3e19b5
nothing to commit, working tree clean
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
Makefile:31: run command via tools/syz-env for best compatibility, see:
Makefile:32: https://github.com/google/syzkaller/blob/master/docs/contributing.md#using-syz-env
go list -f '{{.Stale}}' -ldflags="-s -w -X github.com/google/syzkaller/prog.GitRevision=680aa3e19b52574eca8bcba3c41aa18235367abe -X github.com/google/syzkaller/prog.gitRevisionDate=20260907-094615" ./sys/syz-sysgen | grep -q false || go install -ldflags="-s -w -X github.com/google/syzkaller/prog.GitRevision=680aa3e19b52574eca8bcba3c41aa18235367abe -X github.com/google/syzkaller/prog.gitRevisionDate=20260907-094615" ./sys/syz-sysgen
make .descriptions
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
Makefile:31: run command via tools/syz-env for best compatibility, see:
Makefile:32: https://github.com/google/syzkaller/blob/master/docs/contributing.md#using-syz-env
bin/syz-sysgen
touch .descriptions
GOOS=linux GOARCH=amd64 go build -ldflags="-s -w -X github.com/google/syzkaller/prog.GitRevision=680aa3e19b52574eca8bcba3c41aa18235367abe -X github.com/google/syzkaller/prog.gitRevisionDate=20260907-094615" -o ./bin/linux_amd64/syz-execprog github.com/google/syzkaller/tools/syz-execprog
mkdir -p ./bin/linux_amd64
g++ -o ./bin/linux_amd64/syz-executor executor/executor.cc \
-m64 -O2 -pthread -Wall -Werror -Wparentheses -Wunused-const-variable -Wframe-larger-than=16384 -Wno-stringop-overflow -Wno-array-bounds -Wno-format-overflow -Wno-unused-but-set-variable -Wno-unused-command-line-argument -static-pie -std=c++17 -I. -Iexecutor/_include -DGOOS_linux=1 -DGOARCH_amd64=1 \
-DHOSTGOOS_linux=1 -DGIT_REVISION=\"680aa3e19b52574eca8bcba3c41aa18235367abe\"
/usr/bin/ld: /tmp/ccdJQzUC.o: in function `Connection::Connect(char const*, char const*)':
executor.cc:(.text._ZN10Connection7ConnectEPKcS1_[_ZN10Connection7ConnectEPKcS1_]+0x386): warning: Using 'gethostbyname' in statically linked applications requires at runtime the shared libraries from the glibc version used for linking
./tools/check-syzos.sh 2>/dev/null
Error text is too large and was truncated, full error text is at:
https://syzkaller.appspot.com/x/error.txt?x=164baa15580000
Tested on:
commit: 796aa054 io_uring/rw: end write accounting from ->ki_c..
git tree: git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux.git io_uring-7.3
kernel config: https://syzkaller.appspot.com/x/.config?x=780bb9a5c10069a1
dashboard link: https://syzkaller.appspot.com/bug?extid=2eb3d983669d3e49d4fa
compiler: Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8
Note: no patches were applied.