ci2 starts bisection 2023-12-06 05:01:25.6344224 +0000 UTC m=+39296.626927905
bisecting fixing commit since a343b0dd87b42ba9d508fbf7d0c06f744c2e0954
building syzkaller on cf1845599c0bdab59c69518eaa0ecb960ec7ddf0
ensuring issue is reproducible on original commit a343b0dd87b42ba9d508fbf7d0c06f744c2e0954

testing commit a343b0dd87b42ba9d508fbf7d0c06f744c2e0954 gcc
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
kernel signature: 823d329bd1c508db06141e804721380c5fc226e4f6644b6ef5871d1d76516966
all runs: crashed: possible deadlock in hfsplus_find_init
representative crash: possible deadlock in hfsplus_find_init, types: [LOCKDEP]
check whether we can drop unnecessary instrumentation
disabling configs for [LEAK UBSAN BUG KASAN ATOMIC_SLEEP HANG], they are not needed
testing commit a343b0dd87b42ba9d508fbf7d0c06f744c2e0954 gcc
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
kernel signature: eea628f9375c1d173ee13c6d7f39898112d8bbd76d3dd83513d047cd5c0d0580
all runs: crashed: possible deadlock in hfsplus_find_init
representative crash: possible deadlock in hfsplus_find_init, types: [LOCKDEP]
the bug reproduces without the instrumentation
disabling configs for [ATOMIC_SLEEP HANG LEAK UBSAN BUG KASAN], they are not needed
kconfig minimization: base=3820 full=7523 leaves diff=1994
split chunks (needed=false): <1994>
split chunk #0 of len 1994 into 5 parts
testing without sub-chunk 1/5
disabling configs for [LEAK UBSAN BUG KASAN ATOMIC_SLEEP HANG], they are not needed
testing commit a343b0dd87b42ba9d508fbf7d0c06f744c2e0954 gcc
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
kernel signature: 28cb0658dc7ace27c8c488c5fbe40d46e5194373da27a4eac7cc1d87311b182f
all runs: crashed: possible deadlock in hfsplus_find_init
representative crash: possible deadlock in hfsplus_find_init, types: [LOCKDEP]
the chunk can be dropped
testing without sub-chunk 2/5
disabling configs for [ATOMIC_SLEEP HANG LEAK UBSAN BUG KASAN], they are not needed
testing commit a343b0dd87b42ba9d508fbf7d0c06f744c2e0954 gcc
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
kernel signature: 44a6c33a870573968f6f836ee36b83e5e243d03e54a1baceb820a0bff9676ec4
run #0: failed: failed to run command in VM: broken console: Permission denied (publickey)
run #1: OK
run #2: OK
run #3: OK
run #4: OK
run #5: OK
run #6: OK
run #7: OK
run #8: OK
run #9: OK
false negative chance: 0.000
testing without sub-chunk 3/5
disabling configs for [UBSAN BUG KASAN ATOMIC_SLEEP HANG LEAK], they are not needed
testing commit a343b0dd87b42ba9d508fbf7d0c06f744c2e0954 gcc
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
kernel signature: 55011480a7a90f9fb43efc287bebe395fa50a6816c5e9f0867eaa958fb30832c
all runs: crashed: possible deadlock in hfsplus_find_init
representative crash: possible deadlock in hfsplus_find_init, types: [LOCKDEP]
the chunk can be dropped
testing without sub-chunk 4/5
disabling configs for [LEAK UBSAN BUG KASAN ATOMIC_SLEEP HANG], they are not needed
testing commit a343b0dd87b42ba9d508fbf7d0c06f744c2e0954 gcc
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
kernel signature: 1e7fdcc2216dcd5585c9fe28cb79cab4f0e9b49103b20bc3d66caddb2a88ae2f
all runs: crashed: possible deadlock in hfsplus_find_init
representative crash: possible deadlock in hfsplus_find_init, types: [LOCKDEP]
the chunk can be dropped
testing without sub-chunk 5/5
disabling configs for [LEAK UBSAN BUG KASAN ATOMIC_SLEEP HANG], they are not needed
testing commit a343b0dd87b42ba9d508fbf7d0c06f744c2e0954 gcc
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
kernel signature: 7f1ffbe1df7e03812071b9a2ceac85d6eed9c0e0850b05e56a900cea5a242e19
all runs: crashed: possible deadlock in hfsplus_find_init
representative crash: possible deadlock in hfsplus_find_init, types: [LOCKDEP]
the chunk can be dropped
minimized to 399 configs; suspects: [6LOWPAN ARCH_ENABLE_MEMORY_HOTREMOVE ASUS_WMI CMA COMMON_CLK DAX DLM DRM DRM_BRIDGE DRM_DISPLAY_DP_HELPER DRM_DISPLAY_HDCP_HELPER DRM_DISPLAY_HDMI_HELPER DRM_DISPLAY_HELPER DRM_DP_AUX_BUS DRM_DP_AUX_CHARDEV DRM_FBDEV_EMULATION DRM_GEM_SHMEM_HELPER DRM_I915 DRM_I915_CAPTURE_ERROR DRM_I915_COMPRESS_ERROR DRM_I915_USERPTR DRM_KMS_HELPER DRM_MIPI_DSI DRM_NOMODESET DRM_PANEL DRM_PANEL_BRIDGE DRM_PANEL_EDP DRM_PANEL_ORIENTATION_QUIRKS DRM_SIMPLEDRM DRM_TTM DRM_TTM_HELPER DRM_UDL DRM_VGEM DRM_VIRTIO_GPU DRM_VKMS DRM_VMWGFX DRM_VRAM_HELPER DUMMY DVB_AF9013 DVB_AF9033 DVB_AS102 DVB_AS102_FE DVB_B2C2_FLEXCOP DVB_B2C2_FLEXCOP_USB DVB_CORE DVB_DIB3000MB DVB_DIB3000MC DVB_EC100 DVB_GP8PSK_FE DVB_RTL2830 DVB_RTL2832 DVB_RTL2832_SDR DVB_TEST_DRIVERS DVB_TTUSB_BUDGET DVB_TTUSB_DEC DVB_USB DVB_USB_A800 DVB_USB_AF9005 DVB_USB_AF9005_REMOTE DVB_USB_AF9015 DVB_USB_AF9035 DVB_USB_ANYSEE DVB_USB_AU6610 DVB_USB_AZ6007 DVB_USB_AZ6027 DVB_USB_CE6230 DVB_USB_CINERGY_T2 DVB_USB_CXUSB DVB_USB_DIB0700 DVB_USB_DIB3000MC DVB_USB_DIBUSB_MB DVB_USB_DIBUSB_MC DVB_USB_DIGITV DVB_USB_DTT200U DVB_USB_DTV5100 DVB_USB_DVBSKY DVB_USB_DW2102 DVB_USB_EC168 DVB_USB_GL861 DVB_USB_GP8PSK DVB_USB_LME2510 DVB_USB_M920X DVB_USB_MXL111SF DVB_USB_NOVA_T_USB2 DVB_USB_OPERA1 DVB_USB_PCTV452E DVB_USB_RTL28XXU DVB_USB_TECHNISAT_USB2 DVB_USB_TTUSB2 DVB_USB_UMT_010 DVB_USB_V2 DVB_USB_VP702X DVB_USB_VP7045 DVB_USB_ZD1301 DVB_VIDTV DVB_ZL10353 ECRYPT_FS ECRYPT_FS_MESSAGING EDAC EEPROM_93CX6 EFS_FS ENCRYPTED_KEYS EQUALIZER EROFS_FS EROFS_FS_POSIX_ACL EROFS_FS_SECURITY EROFS_FS_XATTR EROFS_FS_ZIP EVM EVM_ADD_XATTRS EVM_ATTR_FSUUID EXFAT_FS EXPORTFS_BLOCK_OPS EXT3_FS EXT3_FS_POSIX_ACL EXT3_FS_SECURITY EXTCON EXTCON_INTEL_CHT_WC F2FS_CHECK_FS F2FS_FAULT_INJECTION F2FS_FS F2FS_FS_COMPRESSION F2FS_FS_LZ4 F2FS_FS_LZ4HC F2FS_FS_LZO F2FS_FS_LZORLE F2FS_FS_POSIX_ACL F2FS_FS_SECURITY F2FS_FS_XATTR F2FS_FS_ZSTD F2FS_STAT_FS FANOTIFY FANOTIFY_ACCESS_PERMISSIONS FB FB_CFB_COPYAREA FB_CFB_FILLRECT FB_CFB_IMAGEBLIT FB_CMDLINE FB_DEFERRED_IO FB_NOTIFY FB_SYS_COPYAREA FB_SYS_FILLRECT FB_SYS_FOPS FB_SYS_IMAGEBLIT FB_TILEBLITTING FB_VESA FB_VGA16 FB_VIRTUAL FDDI FIREWIRE FIREWIRE_NET FIREWIRE_OHCI FIREWIRE_SBP2 FONT_8x16 FONT_8x8 FONT_SUPPORT FRAMEBUFFER_CONSOLE FRAMEBUFFER_CONSOLE_DETECT_PRIMARY FRAMEBUFFER_CONSOLE_ROTATION FRONTSWAP FS_DAX FS_DAX_PMD FS_ENCRYPTION FS_ENCRYPTION_ALGS FS_VERITY FS_VERITY_BUILTIN_SIGNATURES FTL FUSE_DAX FUSE_FS FW_LOADER_COMPRESS FW_LOADER_PAGED_BUF FW_LOADER_SYSFS FW_LOADER_USER_HELPER FW_LOADER_USER_HELPER_FALLBACK GACT_PROB GARP GENERIC_PHY GET_FREE_REGION GFS2_FS GFS2_FS_LOCKING_DLM GOOGLE_COREBOOT_TABLE GOOGLE_FIRMWARE GOOGLE_MEMCONSOLE GOOGLE_MEMCONSOLE_COREBOOT GOOGLE_VPD GPIOLIB GPIOLIB_IRQCHIP GPIO_ACPI GPIO_DLN2 GPIO_VIPERBOARD GREENASIA_FF GREYBUS GREYBUS_BRIDGED_PHY GREYBUS_ES2 GREYBUS_HID GREYBUS_USB GTP GUEST_PERF_EVENTS GVE HAVE_ARCH_NODE_DEV_GROUP HAVE_ARCH_USERFAULTFD_MINOR HAVE_ARCH_USERFAULTFD_WP HAVE_BOOTMEM_INFO_NODE HAVE_CLK_PREPARE HAVE_KVM_CPU_RELAX_INTERCEPT HAVE_KVM_DIRTY_RING HAVE_KVM_DIRTY_RING_ACQ_REL HAVE_KVM_DIRTY_RING_TSO HAVE_KVM_EVENTFD HAVE_KVM_IRQCHIP HAVE_KVM_IRQFD HAVE_KVM_IRQ_BYPASS HAVE_KVM_IRQ_ROUTING HAVE_KVM_MSI HAVE_KVM_NO_POLL HAVE_KVM_PFNCACHE HAVE_KVM_PM_NOTIFIER HAVE_SCHED_AVG_IRQ HDLC HDLC_CISCO HDLC_FR HDLC_PPP HDLC_RAW HDLC_RAW_ETH HDLC_X25 HDMI HFSPLUS_FS HFS_FS HID_ACCUTOUCH HID_ACRUX HID_ACRUX_FF HID_ALPS HID_APPLEIR HID_ASUS HID_AUREAL HID_BATTERY_STRENGTH HID_BETOP_FF HID_CMEDIA HID_CORSAIR HID_CP2112 HID_ELECOM HID_ELO HID_EMS_FF HID_GEMBIRD HID_GFRM HID_GREENASIA HID_GT683R HID_HOLTEK HID_ICADE HID_KEYTOUCH HID_KYE HID_LCPOWER HID_LED HID_LENOVO HID_LOGITECH_DJ HID_LOGITECH_HIDPP HID_MAGICMOUSE HID_MAYFLASH HID_MULTITOUCH HID_NTI HID_ORTEK HID_PENMOUNT HID_PICOLCD HID_PICOLCD_BACKLIGHT HID_PICOLCD_CIR HID_PICOLCD_FB HID_PICOLCD_LCD HID_PICOLCD_LEDS HID_PLANTRONICS HID_PRIMAX HID_PRODIKEYS HID_RETRODE HID_RMI HID_ROCCAT HID_SAITEK HID_SENSOR_ACCEL_3D HID_SENSOR_ALS HID_SENSOR_CUSTOM_SENSOR HID_SENSOR_DEVICE_ROTATION HID_SENSOR_GYRO_3D HID_SENSOR_HUB HID_SENSOR_HUMIDITY HID_SENSOR_IIO_COMMON HID_SENSOR_IIO_TRIGGER HID_SENSOR_INCLINOMETER_3D HID_SENSOR_MAGNETOMETER_3D HID_SENSOR_PRESS HID_SENSOR_PROX HID_SENSOR_TEMP HID_SPEEDLINK HID_STEELSERIES HID_THINGM HID_TIVO HID_TWINHAN HID_UCLOGIC HID_UDRAW_PS3 HID_WACOM HID_WALTOP HID_WIIMOTE HID_XINMO HID_ZYDACRON HMM_MIRROR HOLTEK_FF HOTPLUG_PCI_PCIE HPET_MMAP HPET_MMAP_DEFAULT HPFS_FS I2C_ALGOBIT I2C_CHARDEV I2C_DESIGNWARE_CORE I2C_DESIGNWARE_PLATFORM I2C_DIOLAN_U2C I2C_DLN2 I2C_MUX I2C_MUX_REG I2C_ROBOTFUZZ_OSIF I2C_SI4713 I2C_SLAVE I2C_SLAVE_EEPROM I2C_TINY_USB I2C_VIPERBOARD IEEE802154 IEEE802154_6LOWPAN IEEE802154_ATUSB IEEE802154_DRIVERS IEEE802154_HWSIM IEEE802154_NL802154_EXPERIMENTAL IEEE802154_SOCKET IFB IIO IIO_BUFFER IIO_KFIFO_BUF IIO_TRIGGER IIO_TRIGGERED_BUFFER IKCONFIG IKCONFIG_PROC IMA IMA_APPRAISE IMA_APPRAISE_MODSIG IMA_DEFAULT_HASH_SHA256 IMA_LSM_RULES IMA_MEASURE_ASYMMETRIC_KEYS IMA_NG_TEMPLATE IMA_QUEUE_EARLY_BOOT_KEYS IMA_READ_POLICY IMA_WRITE_POLICY INET6_ESPINTCP INET6_ESP_OFFLOAD INET6_IPCOMP INET6_TUNNEL INET6_XFRM_TUNNEL INET_AH INET_DCCP_DIAG INET_DIAG INET_DIAG_DESTROY INET_ESP INET_ESPINTCP INET_ESP_OFFLOAD INET_IPCOMP INET_MPTCP_DIAG INET_RAW_DIAG INET_SCTP_DIAG INET_TCP_DIAG INET_UDP_DIAG INET_XFRM_TUNNEL INFINIBAND INFINIBAND_ADDR_TRANS INFINIBAND_ADDR_TRANS_CONFIGFS INFINIBAND_IPOIB INFINIBAND_IPOIB_CM INFINIBAND_IPOIB_DEBUG INFINIBAND_ISER INFINIBAND_ON_DEMAND_PAGING INFINIBAND_RTRS INFINIBAND_SRP INFINIBAND_USER_ACCESS INFINIBAND_USER_MAD INFINIBAND_USER_MEM INPUT_ATI_REMOTE2 INPUT_CM109 INPUT_IMS_PCU INPUT_JOYDEV INPUT_KEYSPAN_REMOTE INPUT_LEDS INPUT_MOUSEDEV INPUT_MOUSEDEV_PSAUX INPUT_POWERMATE INPUT_UINPUT INPUT_YEALINK INTEGRITY INTEGRITY_ASYMMETRIC_KEYS INTEGRITY_AUDIT INTEGRITY_SIGNATURE INTEGRITY_TRUSTED_KEYRING INTEL_IDMA64 INTEL_IOATDMA INTEL_IOMMU_DEFAULT_ON INTEL_IOMMU_SVM INTEL_SOC_PMIC_CHTWC INTERVAL_TREE IOMMU_SVA IP6_NF_MATCH_AH IP6_NF_MATCH_EUI64 IP6_NF_MATCH_FRAG IP6_NF_MATCH_HL IP6_NF_MATCH_MH IP6_NF_MATCH_OPTS IP6_NF_MATCH_RPFILTER IP6_NF_MATCH_RT IP6_NF_MATCH_SRH IP6_NF_NAT IP6_NF_RAW IP6_NF_SECURITY IP6_NF_TARGET_HL IP6_NF_TARGET_MASQUERADE IP6_NF_TARGET_NPT IP6_NF_TARGET_SYNPROXY IPV6_FOU IPV6_FOU_TUNNEL IPV6_GRE IPV6_ILA IPV6_MIP6 IPV6_MROUTE IPV6_MROUTE_MULTIPLE_TABLES IPV6_MULTIPLE_TABLES IPV6_OPTIMISTIC_DAD IPV6_PIMSM_V2 IPV6_ROUTER_PREF IPV6_ROUTE_INFO IPV6_RPL_LWTUNNEL IPV6_SEG6_BPF IPV6_SEG6_HMAC IPV6_SEG6_LWTUNNEL IPV6_SIT_6RD IPV6_SUBTREES IPV6_TUNNEL IPV6_VTI IPVLAN IPVLAN_L3S IPVTAP IP_DCCP IP_DCCP_CCID3 IP_DCCP_TFRC_LIB IP_FIB_TRIE_STATS IP_MROUTE_MULTIPLE_TABLES IP_NF_ARPFILTER IP_NF_ARPTABLES IP_NF_ARP_MANGLE IP_NF_MATCH_AH IP_NF_MATCH_ECN IP_NF_MATCH_RPFILTER IP_NF_MATCH_TTL IP_NF_RAW IP_NF_SECURITY IP_NF_TARGET_CLUSTERIP IP_NF_TARGET_ECN IP_NF_TARGET_NETMAP IP_NF_TARGET_REDIRECT IP_NF_TARGET_SYNPROXY IP_NF_TARGET_TTL IP_ROUTE_CLASSID IP_SCTP IP_SET IP_SET_BITMAP_IP IP_SET_BITMAP_IPMAC IP_SET_BITMAP_PORT IP_SET_HASH_IP IP_SET_HASH_IPMAC IP_SET_HASH_IPMARK IP_SET_HASH_IPPORT IP_SET_HASH_IPPORTIP IP_SET_HASH_IPPORTNET IP_SET_HASH_MAC IP_SET_HASH_NET IP_SET_HASH_NETIFACE IP_SET_HASH_NETNET IP_SET_HASH_NETPORT IP_SET_HASH_NETPORTNET IP_SET_LIST_SET IP_VS IP_VS_DH IP_VS_FO IP_VS_FTP IP_VS_IPV6 IP_VS_LBLC IP_VS_LBLCR IP_VS_LC IP_VS_MH IP_VS_NFCT IP_VS_NQ IP_VS_OVF IP_VS_PE_SIP IP_VS_PROTO_TCP IP_VS_PROTO_UDP IRQ_TIME_ACCOUNTING LAPB LCD_CLASS_DEVICE MAC802154 MEDIA_DIGITAL_TV_SUPPORT MEDIA_RADIO_SUPPORT MEDIA_SDR_SUPPORT MEDIA_SUPPORT MEDIA_TEST_SUPPORT MEDIA_USB_SUPPORT MEMORY_HOTPLUG MEMORY_HOTREMOVE MFD_DLN2 MFD_VIPERBOARD MPTCP MTD NETFILTER_ADVANCED NET_ACT_GACT NET_ACT_MIRRED NET_IPGRE_DEMUX NFT_FWD_NETDEV NF_TABLES NF_TABLES_NETDEV RADIO_ADAPTERS RADIO_SI4713 RAS RC_CORE RFKILL SND SOUND STAGING TRANSPARENT_HUGEPAGE VIDEO_DEV VIRTIO_FS WAN ZONE_DEVICE]
disabling configs for [KASAN ATOMIC_SLEEP HANG LEAK UBSAN BUG], they are not needed
testing current HEAD c6114c845984144944f1abc07c61de219367a4da
testing commit c6114c845984144944f1abc07c61de219367a4da gcc
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
kernel signature: 24fead541634b4db776f5b605f66823b9cac3b079ef62d5414f0bf70cb90b1b2
all runs: crashed: possible deadlock in hfsplus_find_init
representative crash: possible deadlock in hfsplus_find_init, types: [LOCKDEP]
crash still not fixed/happens on the oldest tested release
revisions tested: 8, total time: 1h3m9.356870781s (build: 29m16.338679353s, test: 31m14.098597616s)
crash still not fixed or there were kernel test errors
commit msg: Linux 6.1.65
crash: possible deadlock in hfsplus_find_init
============================================
WARNING: possible recursive locking detected
6.1.65-syzkaller #0 Not tainted
--------------------------------------------
kworker/u4:4/287 is trying to acquire lock:
ffff88810c6d50b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfsplus_find_init+0x6f/0x80

but task is already holding lock:
ffff88810c6d50b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfsplus_find_init+0x6f/0x80

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(&tree->tree_lock/1);
  lock(&tree->tree_lock/1);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

5 locks held by kworker/u4:4/287:
 #0: ffff888100340538 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x1da/0x470 kernel/workqueue.c:2267
 #1: ffffc900014a3e68 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x1da/0x470 kernel/workqueue.c:2267
 #2: ffff888107b62688 (&hip->extents_lock){+.+.}-{3:3}, at: hfsplus_ext_write_extent+0x2e/0xe0 fs/hfsplus/extents.c:149
 #3: ffff88810c6d50b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfsplus_find_init+0x6f/0x80
 #4: ffff888107b60108 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{3:3}, at: hfsplus_file_extend+0x6d/0x560 fs/hfsplus/extents.c:457

stack backtrace:
CPU: 1 PID: 287 Comm: kworker/u4:4 Not tainted 6.1.65-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
Workqueue: writeback wb_workfn (flush-7:0)
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x89/0xd7 lib/dump_stack.c:106
 __lock_acquire+0x73d/0x2830
 lock_acquire+0xe3/0x270 kernel/locking/lockdep.c:5662
 __mutex_lock_common kernel/locking/mutex.c:603 [inline]
 __mutex_lock+0x99/0x970 kernel/locking/mutex.c:747
 hfsplus_find_init+0x6f/0x80
 hfsplus_ext_read_extent fs/hfsplus/extents.c:216 [inline]
 hfsplus_file_extend+0x114/0x560 fs/hfsplus/extents.c:461
 hfsplus_bmap_reserve+0x33/0xb0 fs/hfsplus/btree.c:358
 __hfsplus_ext_write_extent+0x91/0xc0 fs/hfsplus/extents.c:104
 hfsplus_ext_write_extent_locked fs/hfsplus/extents.c:139 [inline]
 hfsplus_ext_write_extent+0xa2/0xe0 fs/hfsplus/extents.c:150
 hfsplus_write_inode+0x10/0x160 fs/hfsplus/super.c:154
 write_inode fs/fs-writeback.c:1460 [inline]
 __writeback_single_inode+0x18f/0x380 fs/fs-writeback.c:1677
 writeback_sb_inodes+0x376/0x700 fs/fs-writeback.c:1903
 wb_writeback+0x179/0x3c0 fs/fs-writeback.c:2077
 wb_do_writeback fs/fs-writeback.c:2220 [inline]
 wb_workfn+0x126/0x500 fs/fs-writeback.c:2260
 process_one_work+0x235/0x470 kernel/workqueue.c:2292
 worker_thread+0x214/0x370 kernel/workqueue.c:2439
 kthread+0xd1/0xe0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
 </TASK>