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write_cache_pages (2) To: "Huang, Ying" Cc: Yang Shi , syzbot , Hugh Dickins , akpm@linux-foundation.org, elver@google.com, glider@google.com, kasan-dev@googlegroups.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 3 Mar 2023 at 00:43, Huang, Ying wrote: > > Yang Shi writes: > > > On Wed, Mar 1, 2023 at 4:36=E2=80=AFPM syzbot > > wrote: > >> > >> Hello, > >> > >> syzbot found the following issue on: > >> > >> HEAD commit: 489fa31ea873 Merge branch 'work.misc' of git://git.ker= nel... > >> git tree: upstream > >> console output: https://syzkaller.appspot.com/x/log.txt?x=3D1034fef8c8= 0000 > >> kernel config: https://syzkaller.appspot.com/x/.config?x=3Dcbfa7a73c5= 40248d > >> dashboard link: https://syzkaller.appspot.com/bug?extid=3D0adf31ecbba8= 86ab504f > >> compiler: Debian clang version 15.0.7, GNU ld (GNU Binutils for = Debian) 2.35.2 > >> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=3D16dc6960= c80000 > >> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=3D16f39d50c8= 0000 > >> > >> Downloadable assets: > >> disk image: https://storage.googleapis.com/syzbot-assets/8121ff3f8044/= disk-489fa31e.raw.xz > >> vmlinux: https://storage.googleapis.com/syzbot-assets/ba8296ba1bf7/vml= inux-489fa31e.xz > >> kernel image: https://storage.googleapis.com/syzbot-assets/6459f50e23f= 3/bzImage-489fa31e.xz > >> mounted in repro: https://storage.googleapis.com/syzbot-assets/845f653= 8108c/mount_1.gz > >> > >> IMPORTANT: if you fix the issue, please add the following tag to the c= ommit: > >> Reported-by: syzbot+0adf31ecbba886ab504f@syzkaller.appspotmail.com > >> > >> INFO: task kworker/u4:0:9 blocked for more than 143 seconds. > >> Not tainted 6.2.0-syzkaller-10827-g489fa31ea873 #0 > >> "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this messa= ge. > >> task:kworker/u4:0 state:D stack:21720 pid:9 ppid:2 flags:0= x00004000 > >> Workqueue: writeback wb_workfn (flush-7:0) > >> Call Trace: > >> > >> context_switch kernel/sched/core.c:5304 [inline] > >> __schedule+0x17d8/0x4990 kernel/sched/core.c:6622 > >> schedule+0xc3/0x180 kernel/sched/core.c:6698 > >> io_schedule+0x8c/0x100 kernel/sched/core.c:8884 > >> folio_wait_bit_common+0x86c/0x12b0 mm/filemap.c:1301 > >> folio_lock include/linux/pagemap.h:952 [inline] > >> write_cache_pages+0x58f/0x1450 mm/page-writeback.c:2440 > >> mpage_writepages+0x107/0x1d0 fs/mpage.c:653 > >> do_writepages+0x3a6/0x670 mm/page-writeback.c:2551 > >> __writeback_single_inode+0x1c4/0x15e0 fs/fs-writeback.c:1600 > >> writeback_sb_inodes+0x92c/0x1360 fs/fs-writeback.c:1891 > >> __writeback_inodes_wb+0x11b/0x260 fs/fs-writeback.c:1962 > >> wb_writeback+0x51c/0x1080 fs/fs-writeback.c:2067 > >> wb_check_background_flush fs/fs-writeback.c:2133 [inline] > >> wb_do_writeback fs/fs-writeback.c:2221 [inline] > >> wb_workfn+0xd80/0x1100 fs/fs-writeback.c:2248 > >> process_one_work+0x915/0x13a0 kernel/workqueue.c:2390 > >> worker_thread+0xa63/0x1210 kernel/workqueue.c:2537 > >> kthread+0x270/0x300 kernel/kthread.c:376 > >> ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 > >> > >> INFO: task kworker/u4:2:41 blocked for more than 143 seconds. > >> Not tainted 6.2.0-syzkaller-10827-g489fa31ea873 #0 > >> "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this messa= ge. > >> task:kworker/u4:2 state:D stack:20480 pid:41 ppid:2 flags:0= x00004000 > >> Workqueue: writeback wb_workfn (flush-7:5) > >> Call Trace: > >> > >> context_switch kernel/sched/core.c:5304 [inline] > >> __schedule+0x17d8/0x4990 kernel/sched/core.c:6622 > >> schedule+0xc3/0x180 kernel/sched/core.c:6698 > >> io_schedule+0x8c/0x100 kernel/sched/core.c:8884 > >> folio_wait_bit_common+0x86c/0x12b0 mm/filemap.c:1301 > >> folio_lock include/linux/pagemap.h:952 [inline] > >> write_cache_pages+0x58f/0x1450 mm/page-writeback.c:2440 > >> mpage_writepages+0x107/0x1d0 fs/mpage.c:653 > >> do_writepages+0x3a6/0x670 mm/page-writeback.c:2551 > >> __writeback_single_inode+0x1c4/0x15e0 fs/fs-writeback.c:1600 > >> writeback_sb_inodes+0x92c/0x1360 fs/fs-writeback.c:1891 > >> __writeback_inodes_wb+0x11b/0x260 fs/fs-writeback.c:1962 > >> wb_writeback+0x51c/0x1080 fs/fs-writeback.c:2067 > >> wb_check_old_data_flush fs/fs-writeback.c:2167 [inline] > >> wb_do_writeback fs/fs-writeback.c:2220 [inline] > >> wb_workfn+0xccb/0x1100 fs/fs-writeback.c:2248 > >> process_one_work+0x915/0x13a0 kernel/workqueue.c:2390 > >> worker_thread+0xa63/0x1210 kernel/workqueue.c:2537 > >> kthread+0x270/0x300 kernel/kthread.c:376 > >> ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 > >> > >> INFO: task kworker/u4:4:75 blocked for more than 144 seconds. > >> Not tainted 6.2.0-syzkaller-10827-g489fa31ea873 #0 > >> "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this messa= ge. > >> task:kworker/u4:4 state:D stack:25088 pid:75 ppid:2 flags:0= x00004000 > >> Workqueue: writeback wb_workfn (flush-7:1) > >> Call Trace: > >> > >> context_switch kernel/sched/core.c:5304 [inline] > >> __schedule+0x17d8/0x4990 kernel/sched/core.c:6622 > >> schedule+0xc3/0x180 kernel/sched/core.c:6698 > >> io_schedule+0x8c/0x100 kernel/sched/core.c:8884 > >> folio_wait_bit_common+0x86c/0x12b0 mm/filemap.c:1301 > >> folio_lock include/linux/pagemap.h:952 [inline] > >> write_cache_pages+0x58f/0x1450 mm/page-writeback.c:2440 > >> mpage_writepages+0x107/0x1d0 fs/mpage.c:653 > >> do_writepages+0x3a6/0x670 mm/page-writeback.c:2551 > >> __writeback_single_inode+0x1c4/0x15e0 fs/fs-writeback.c:1600 > >> writeback_sb_inodes+0x92c/0x1360 fs/fs-writeback.c:1891 > >> __writeback_inodes_wb+0x11b/0x260 fs/fs-writeback.c:1962 > >> wb_writeback+0x51c/0x1080 fs/fs-writeback.c:2067 > >> wb_check_old_data_flush fs/fs-writeback.c:2167 [inline] > >> wb_do_writeback fs/fs-writeback.c:2220 [inline] > >> wb_workfn+0xccb/0x1100 fs/fs-writeback.c:2248 > >> process_one_work+0x915/0x13a0 kernel/workqueue.c:2390 > >> worker_thread+0xa63/0x1210 kernel/workqueue.c:2537 > >> kthread+0x270/0x300 kernel/kthread.c:376 > >> ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 > >> > >> INFO: task syz-executor359:5222 blocked for more than 144 seconds. > >> Not tainted 6.2.0-syzkaller-10827-g489fa31ea873 #0 > >> "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this messa= ge. > >> task:syz-executor359 state:D stack:26576 pid:5222 ppid:5113 flags:0= x00004004 > >> Call Trace: > >> > >> context_switch kernel/sched/core.c:5304 [inline] > >> __schedule+0x17d8/0x4990 kernel/sched/core.c:6622 > >> schedule+0xc3/0x180 kernel/sched/core.c:6698 > >> schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6757 > >> rwsem_down_read_slowpath+0x5f4/0x950 kernel/locking/rwsem.c:1086 > >> __down_read_common+0x61/0x2c0 kernel/locking/rwsem.c:1250 > >> mmap_read_lock include/linux/mmap_lock.h:117 [inline] > >> do_user_addr_fault arch/x86/mm/fault.c:1358 [inline] > >> handle_page_fault arch/x86/mm/fault.c:1498 [inline] > >> exc_page_fault+0x558/0x8a0 arch/x86/mm/fault.c:1554 > >> asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570 > >> RIP: 0033:0x7fd6f371b888 > >> RSP: 002b:00007ffd6fdf2398 EFLAGS: 00010206 > >> RAX: 00007fd6f374ebd0 RBX: 00007fd6f374d1a8 RCX: 0000000000000001 > >> RDX: 00007fd6f3688d30 RSI: 0000000000000000 RDI: 00007fd6f374ebd0 > >> RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000010 > >> R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 > >> R13: 0000000000000001 R14: 00007fd6f37543e0 R15: 0000000000000001 > >> > >> INFO: task syz-executor359:5223 blocked for more than 144 seconds. > >> Not tainted 6.2.0-syzkaller-10827-g489fa31ea873 #0 > >> "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this messa= ge. > >> task:syz-executor359 state:D stack:24840 pid:5223 ppid:5113 flags:0= x00004004 > >> Call Trace: > >> > >> context_switch kernel/sched/core.c:5304 [inline] > >> __schedule+0x17d8/0x4990 kernel/sched/core.c:6622 > >> schedule+0xc3/0x180 kernel/sched/core.c:6698 > >> io_schedule+0x8c/0x100 kernel/sched/core.c:8884 > >> folio_wait_bit_common+0x86c/0x12b0 mm/filemap.c:1301 > >> folio_lock include/linux/pagemap.h:952 [inline] > >> write_cache_pages+0x58f/0x1450 mm/page-writeback.c:2440 > >> mpage_writepages+0x107/0x1d0 fs/mpage.c:653 > >> do_writepages+0x3a6/0x670 mm/page-writeback.c:2551 > >> filemap_fdatawrite_wbc+0x125/0x180 mm/filemap.c:390 > >> __filemap_fdatawrite_range mm/filemap.c:423 [inline] > >> file_write_and_wait_range+0x20f/0x300 mm/filemap.c:781 > >> __generic_file_fsync+0x72/0x190 fs/libfs.c:1132 > >> fat_file_fsync+0x7e/0x190 fs/fat/file.c:191 > >> generic_write_sync include/linux/fs.h:2452 [inline] > >> generic_file_write_iter+0x2a1/0x310 mm/filemap.c:4090 > >> call_write_iter include/linux/fs.h:1851 [inline] > >> new_sync_write fs/read_write.c:491 [inline] > >> vfs_write+0x7b2/0xbb0 fs/read_write.c:584 > >> ksys_write+0x1a0/0x2c0 fs/read_write.c:637 > >> do_syscall_x64 arch/x86/entry/common.c:50 [inline] > >> do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 > >> entry_SYSCALL_64_after_hwframe+0x63/0xcd > >> RIP: 0033:0x7fd6f36ca719 > >> RSP: 002b:00007fd6f36762f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 > >> RAX: ffffffffffffffda RBX: 00007fd6f374f7a0 RCX: 00007fd6f36ca719 > >> RDX: 000000000208e24b RSI: 0000000020000080 RDI: 0000000000000004 > >> RBP: 00007fd6f371c604 R08: 0000000000000000 R09: 0000000000000000 > >> R10: 0000000000000000 R11: 0000000000000246 R12: 00007fd6f371c0e0 > >> R13: 0000000020000a80 R14: 0030656c69662f2e R15: 00007fd6f374f7a8 > >> > >> INFO: task syz-executor359:5229 blocked for more than 144 seconds. > >> Not tainted 6.2.0-syzkaller-10827-g489fa31ea873 #0 > >> "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this messa= ge. > >> task:syz-executor359 state:D stack:26504 pid:5229 ppid:5113 flags:0= x00004004 > >> Call Trace: > >> > >> context_switch kernel/sched/core.c:5304 [inline] > >> __schedule+0x17d8/0x4990 kernel/sched/core.c:6622 > >> schedule+0xc3/0x180 kernel/sched/core.c:6698 > >> io_schedule+0x8c/0x100 kernel/sched/core.c:8884 > >> folio_wait_bit_common+0x86c/0x12b0 mm/filemap.c:1301 > >> folio_wait_writeback+0xec/0x1f0 mm/page-writeback.c:3127 > >> migrate_folio_unmap mm/migrate.c:1192 [inline] > >> migrate_pages_batch mm/migrate.c:1685 [inline] > >> migrate_pages+0x2d50/0x6610 mm/migrate.c:1973 > > > > The migration has locked the page, but is waiting for writeback. The > > writeback is waiting for the page lock... > > > > I recalled Huge reported the same bug. There is a patch to solve it, > > but may be not shown in linus's tree yet. And It seems like the > > reproducer is dirtying some files on loop device and calling mbind at > > the same time. This does match the reproducer mentioned by Hugh. > > Yes. We have fixed a bug report similar. The fix patchset is as > follows, > > https://lore.kernel.org/linux-mm/20230224141145.96814-1-ying.huang@intel.= com/ > > It will take some time for it to land in Linus's tree. Let's tell the bot about the fix so that it reports similar issues in futur= e: #syz fix: migrate_pages: fix deadlock in batched migration > Best Regards, > Huang, Ying > > >> do_mbind mm/mempolicy.c:1338 [inline] > >> kernel_mbind mm/mempolicy.c:1485 [inline] > >> __do_sys_mbind mm/mempolicy.c:1559 [inline] > >> __se_sys_mbind+0x75a/0x9c0 mm/mempolicy.c:1555 > >> do_syscall_x64 arch/x86/entry/common.c:50 [inline] > >> do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 > >> entry_SYSCALL_64_after_hwframe+0x63/0xcd > >> RIP: 0033:0x7fd6f36ca719 > >> RSP: 002b:00007fd6eb3552e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ed > >> RAX: ffffffffffffffda RBX: 00007fd6f374f7b0 RCX: 00007fd6f36ca719 > >> RDX: 0000000000000000 RSI: 0000000000800000 RDI: 0000000020001000 > >> RBP: 00007fd6f371c604 R08: 0000000000000000 R09: 0000000000000002 > >> R10: 0000000000000000 R11: 0000000000000246 R12: 00007fd6f371c0e0 > >> R13: 0000000020000a80 R14: 0030656c69662f2e R15: 00007fd6f374f7b8 > >> > >> INFO: task syz-executor359:5296 blocked for more than 145 seconds. > >> Not tainted 6.2.0-syzkaller-10827-g489fa31ea873 #0 > >> "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this messa= ge. > >> task:syz-executor359 state:D stack:27008 pid:5296 ppid:5112 flags:0= x00004004 > >> Call Trace: > >> > >> context_switch kernel/sched/core.c:5304 [inline] > >> __schedule+0x17d8/0x4990 kernel/sched/core.c:6622 > >> schedule+0xc3/0x180 kernel/sched/core.c:6698 > >> schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6757 > >> rwsem_down_read_slowpath+0x5f4/0x950 kernel/locking/rwsem.c:1086 > >> __down_read_common+0x61/0x2c0 kernel/locking/rwsem.c:1250 > >> mmap_read_lock include/linux/mmap_lock.h:117 [inline] > >> do_user_addr_fault arch/x86/mm/fault.c:1358 [inline] > >> handle_page_fault arch/x86/mm/fault.c:1498 [inline] > >> exc_page_fault+0x558/0x8a0 arch/x86/mm/fault.c:1554 > >> asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570 > >> RIP: 0033:0x7fd6f371b888 > >> RSP: 002b:00007ffd6fdf2398 EFLAGS: 00010206 > >> RAX: 00007fd6f374ebd0 RBX: 00007fd6f374d1a8 RCX: 0000000000000001 > >> RDX: 00007fd6f3688d30 RSI: 0000000000000000 RDI: 00007fd6f374ebd0 > >> RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000010 > >> R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 > >> R13: 0000000000000001 R14: 00007fd6f37543e0 R15: 0000000000000001 > >> > >> INFO: task syz-executor359:5298 blocked for more than 145 seconds. > >> Not tainted 6.2.0-syzkaller-10827-g489fa31ea873 #0 > >> "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this messa= ge. > >> task:syz-executor359 state:D stack:24840 pid:5298 ppid:5112 flags:0= x00004004 > >> Call Trace: > >> > >> context_switch kernel/sched/core.c:5304 [inline] > >> __schedule+0x17d8/0x4990 kernel/sched/core.c:6622 > >> schedule+0xc3/0x180 kernel/sched/core.c:6698 > >> io_schedule+0x8c/0x100 kernel/sched/core.c:8884 > >> folio_wait_bit_common+0x86c/0x12b0 mm/filemap.c:1301 > >> folio_lock include/linux/pagemap.h:952 [inline] > >> write_cache_pages+0x58f/0x1450 mm/page-writeback.c:2440 > >> mpage_writepages+0x107/0x1d0 fs/mpage.c:653 > >> do_writepages+0x3a6/0x670 mm/page-writeback.c:2551 > >> filemap_fdatawrite_wbc+0x125/0x180 mm/filemap.c:390 > >> __filemap_fdatawrite_range mm/filemap.c:423 [inline] > >> file_write_and_wait_range+0x20f/0x300 mm/filemap.c:781 > >> __generic_file_fsync+0x72/0x190 fs/libfs.c:1132 > >> fat_file_fsync+0x7e/0x190 fs/fat/file.c:191 > >> generic_write_sync include/linux/fs.h:2452 [inline] > >> generic_file_write_iter+0x2a1/0x310 mm/filemap.c:4090 > >> call_write_iter include/linux/fs.h:1851 [inline] > >> new_sync_write fs/read_write.c:491 [inline] > >> vfs_write+0x7b2/0xbb0 fs/read_write.c:584 > >> ksys_write+0x1a0/0x2c0 fs/read_write.c:637 > >> do_syscall_x64 arch/x86/entry/common.c:50 [inline] > >> do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 > >> entry_SYSCALL_64_after_hwframe+0x63/0xcd > >> RIP: 0033:0x7fd6f36ca719 > >> RSP: 002b:00007fd6f36762f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 > >> RAX: ffffffffffffffda RBX: 00007fd6f374f7a0 RCX: 00007fd6f36ca719 > >> RDX: 000000000208e24b RSI: 0000000020000080 RDI: 0000000000000004 > >> RBP: 00007fd6f371c604 R08: 0000000000000000 R09: 0000000000000000 > >> R10: 0000000000000000 R11: 0000000000000246 R12: 00007fd6f371c0e0 > >> R13: 0000000020000a80 R14: 0030656c69662f2e R15: 00007fd6f374f7a8 > >> > >> INFO: task syz-executor359:5304 blocked for more than 145 seconds. > >> Not tainted 6.2.0-syzkaller-10827-g489fa31ea873 #0 > >> "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this messa= ge. > >> task:syz-executor359 state:D stack:26504 pid:5304 ppid:5112 flags:0= x00004004 > >> Call Trace: > >> > >> context_switch kernel/sched/core.c:5304 [inline] > >> __schedule+0x17d8/0x4990 kernel/sched/core.c:6622 > >> schedule+0xc3/0x180 kernel/sched/core.c:6698 > >> io_schedule+0x8c/0x100 kernel/sched/core.c:8884 > >> folio_wait_bit_common+0x86c/0x12b0 mm/filemap.c:1301 > >> folio_wait_writeback+0xec/0x1f0 mm/page-writeback.c:3127 > >> migrate_folio_unmap mm/migrate.c:1192 [inline] > >> migrate_pages_batch mm/migrate.c:1685 [inline] > >> migrate_pages+0x2d50/0x6610 mm/migrate.c:1973 > >> do_mbind mm/mempolicy.c:1338 [inline] > >> kernel_mbind mm/mempolicy.c:1485 [inline] > >> __do_sys_mbind mm/mempolicy.c:1559 [inline] > >> __se_sys_mbind+0x75a/0x9c0 mm/mempolicy.c:1555 > >> do_syscall_x64 arch/x86/entry/common.c:50 [inline] > >> do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 > >> entry_SYSCALL_64_after_hwframe+0x63/0xcd > >> RIP: 0033:0x7fd6f36ca719 > >> RSP: 002b:00007fd6eb3552e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ed > >> RAX: ffffffffffffffda RBX: 00007fd6f374f7b0 RCX: 00007fd6f36ca719 > >> RDX: 0000000000000000 RSI: 0000000000800000 RDI: 0000000020001000 > >> RBP: 00007fd6f371c604 R08: 0000000000000000 R09: 0000000000000002 > >> R10: 0000000000000000 R11: 0000000000000246 R12: 00007fd6f371c0e0 > >> R13: 0000000020000a80 R14: 0030656c69662f2e R15: 00007fd6f374f7b8 > >> > >> INFO: task syz-executor359:5460 blocked for more than 146 seconds. > >> Not tainted 6.2.0-syzkaller-10827-g489fa31ea873 #0 > >> "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this messa= ge. > >> task:syz-executor359 state:D stack:26520 pid:5460 ppid:5115 flags:0= x00004004 > >> Call Trace: > >> > >> context_switch kernel/sched/core.c:5304 [inline] > >> __schedule+0x17d8/0x4990 kernel/sched/core.c:6622 > >> schedule+0xc3/0x180 kernel/sched/core.c:6698 > >> schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6757 > >> rwsem_down_read_slowpath+0x5f4/0x950 kernel/locking/rwsem.c:1086 > >> __down_read_common+0x61/0x2c0 kernel/locking/rwsem.c:1250 > >> mmap_read_lock include/linux/mmap_lock.h:117 [inline] > >> do_user_addr_fault arch/x86/mm/fault.c:1358 [inline] > >> handle_page_fault arch/x86/mm/fault.c:1498 [inline] > >> exc_page_fault+0x558/0x8a0 arch/x86/mm/fault.c:1554 > >> asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570 > >> RIP: 0033:0x7fd6f371b888 > >> RSP: 002b:00007ffd6fdf2398 EFLAGS: 00010206 > >> RAX: 00007fd6f374ebd0 RBX: 00007fd6f374d1a8 RCX: 0000000000000001 > >> RDX: 00007fd6f3688d30 RSI: 0000000000000000 RDI: 00007fd6f374ebd0 > >> RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000010 > >> R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 > >> R13: 0000000000000001 R14: 00007fd6f37543e0 R15: 0000000000000001 > >> > >> Future hung task reports are suppressed, see sysctl kernel.hung_task_w= arnings > >> > >> Showing all locks held in the system: > >> 3 locks held by kworker/u4:0/9: > >> #0: ffff8881451bb938 ((wq_completion)writeback){+.+.}-{0:0}, at: proc= ess_one_work+0x77f/0x13a0 > >> #1: ffffc900000e7d20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{= 0:0}, at: process_one_work+0x7c6/0x13a0 kernel/workqueue.c:2365 > >> #2: ffff88807dfe20e0 (&type->s_umount_key#43){++++}-{3:3}, at: tryloc= k_super+0x1f/0xf0 fs/super.c:414 > >> 1 lock held by rcu_tasks_kthre/12: > >> #0: ffffffff8d127cf0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_= tasks_one_gp+0x29/0xd20 kernel/rcu/tasks.h:510 > >> 1 lock held by rcu_tasks_trace/13: > >> #0: ffffffff8d1284f0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at= : rcu_tasks_one_gp+0x29/0xd20 kernel/rcu/tasks.h:510 > >> 1 lock held by khungtaskd/28: > >> #0: ffffffff8d127b20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquir= e+0x0/0x30 > >> 3 locks held by kworker/u4:2/41: > >> #0: ffff8881451bb938 ((wq_completion)writeback){+.+.}-{0:0}, at: proc= ess_one_work+0x77f/0x13a0 > >> #1: ffffc90000b27d20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{= 0:0}, at: process_one_work+0x7c6/0x13a0 kernel/workqueue.c:2365 > >> #2: ffff88801d8680e0 (&type->s_umount_key#43){++++}-{3:3}, at: tryloc= k_super+0x1f/0xf0 fs/super.c:414 > >> 3 locks held by kworker/u4:4/75: > >> #0: ffff8881451bb938 ((wq_completion)writeback){+.+.}-{0:0}, at: proc= ess_one_work+0x77f/0x13a0 > >> #1: ffffc900020efd20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{= 0:0}, at: process_one_work+0x7c6/0x13a0 kernel/workqueue.c:2365 > >> #2: ffff88802c2640e0 (&type->s_umount_key#43){++++}-{3:3}, at: tryloc= k_super+0x1f/0xf0 fs/super.c:414 > >> 2 locks held by kworker/1:2/2494: > >> #0: ffff888012472538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process= _one_work+0x77f/0x13a0 > >> #1: ffffc9000a86fd20 ((work_completion)(&rew->rew_work)){+.+.}-{0:0},= at: process_one_work+0x7c6/0x13a0 kernel/workqueue.c:2365 > >> 2 locks held by getty/4750: > >> #0: ffff88814a0e2098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref= _wait+0x25/0x70 drivers/tty/tty_ldisc.c:244 > >> #1: ffffc900015802f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tt= y_read+0x6ab/0x1db0 drivers/tty/n_tty.c:2177 > >> 1 lock held by syz-executor359/5222: > >> #0: ffff88807d1df698 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_lock= include/linux/mmap_lock.h:117 [inline] > >> #0: ffff88807d1df698 (&mm->mmap_lock){++++}-{3:3}, at: do_user_addr_f= ault arch/x86/mm/fault.c:1358 [inline] > >> #0: ffff88807d1df698 (&mm->mmap_lock){++++}-{3:3}, at: handle_page_fa= ult arch/x86/mm/fault.c:1498 [inline] > >> #0: ffff88807d1df698 (&mm->mmap_lock){++++}-{3:3}, at: exc_page_fault= +0x558/0x8a0 arch/x86/mm/fault.c:1554 > >> 2 locks held by syz-executor359/5223: > >> #0: ffff888021e0f768 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x= 254/0x2f0 fs/file.c:1046 > >> #1: ffff88802c264460 (sb_writers#9){.+.+}-{0:0}, at: vfs_write+0x26d/= 0xbb0 fs/read_write.c:580 > >> 1 lock held by syz-executor359/5229: > >> #0: ffff88807d1df698 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_loc= k include/linux/mmap_lock.h:71 [inline] > >> #0: ffff88807d1df698 (&mm->mmap_lock){++++}-{3:3}, at: do_mbind mm/me= mpolicy.c:1312 [inline] > >> #0: ffff88807d1df698 (&mm->mmap_lock){++++}-{3:3}, at: kernel_mbind m= m/mempolicy.c:1485 [inline] > >> #0: ffff88807d1df698 (&mm->mmap_lock){++++}-{3:3}, at: __do_sys_mbind= mm/mempolicy.c:1559 [inline] > >> #0: ffff88807d1df698 (&mm->mmap_lock){++++}-{3:3}, at: __se_sys_mbind= +0x47d/0x9c0 mm/mempolicy.c:1555 > >> 1 lock held by syz-executor359/5296: > >> #0: ffff88802cd0ae98 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_lock= include/linux/mmap_lock.h:117 [inline] > >> #0: ffff88802cd0ae98 (&mm->mmap_lock){++++}-{3:3}, at: do_user_addr_f= ault arch/x86/mm/fault.c:1358 [inline] > >> #0: ffff88802cd0ae98 (&mm->mmap_lock){++++}-{3:3}, at: handle_page_fa= ult arch/x86/mm/fault.c:1498 [inline] > >> #0: ffff88802cd0ae98 (&mm->mmap_lock){++++}-{3:3}, at: exc_page_fault= +0x558/0x8a0 arch/x86/mm/fault.c:1554 > >> 2 locks held by syz-executor359/5298: > >> #0: ffff88807e2b0fe8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x= 254/0x2f0 fs/file.c:1046 > >> #1: ffff88807dfe2460 (sb_writers#9){.+.+}-{0:0}, at: vfs_write+0x26d/= 0xbb0 fs/read_write.c:580 > >> 1 lock held by syz-executor359/5304: > >> #0: ffff88802cd0ae98 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_loc= k include/linux/mmap_lock.h:71 [inline] > >> #0: ffff88802cd0ae98 (&mm->mmap_lock){++++}-{3:3}, at: do_mbind mm/me= mpolicy.c:1312 [inline] > >> #0: ffff88802cd0ae98 (&mm->mmap_lock){++++}-{3:3}, at: kernel_mbind m= m/mempolicy.c:1485 [inline] > >> #0: ffff88802cd0ae98 (&mm->mmap_lock){++++}-{3:3}, at: __do_sys_mbind= mm/mempolicy.c:1559 [inline] > >> #0: ffff88802cd0ae98 (&mm->mmap_lock){++++}-{3:3}, at: __se_sys_mbind= +0x47d/0x9c0 mm/mempolicy.c:1555 > >> 1 lock held by syz-executor359/5460: > >> #0: ffff888022485298 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_lock= include/linux/mmap_lock.h:117 [inline] > >> #0: ffff888022485298 (&mm->mmap_lock){++++}-{3:3}, at: do_user_addr_f= ault arch/x86/mm/fault.c:1358 [inline] > >> #0: ffff888022485298 (&mm->mmap_lock){++++}-{3:3}, at: handle_page_fa= ult arch/x86/mm/fault.c:1498 [inline] > >> #0: ffff888022485298 (&mm->mmap_lock){++++}-{3:3}, at: exc_page_fault= +0x558/0x8a0 arch/x86/mm/fault.c:1554 > >> 2 locks held by syz-executor359/5461: > >> #0: ffff88801da66ae8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x= 254/0x2f0 fs/file.c:1046 > >> #1: ffff888148d0a460 (sb_writers#9){.+.+}-{0:0}, at: vfs_write+0x26d/= 0xbb0 fs/read_write.c:580 > >> 1 lock held by syz-executor359/5467: > >> #0: ffff888022485298 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_loc= k include/linux/mmap_lock.h:71 [inline] > >> #0: ffff888022485298 (&mm->mmap_lock){++++}-{3:3}, at: do_mbind mm/me= mpolicy.c:1312 [inline] > >> #0: ffff888022485298 (&mm->mmap_lock){++++}-{3:3}, at: kernel_mbind m= m/mempolicy.c:1485 [inline] > >> #0: ffff888022485298 (&mm->mmap_lock){++++}-{3:3}, at: __do_sys_mbind= mm/mempolicy.c:1559 [inline] > >> #0: ffff888022485298 (&mm->mmap_lock){++++}-{3:3}, at: __se_sys_mbind= +0x47d/0x9c0 mm/mempolicy.c:1555 > >> 1 lock held by syz-executor359/5570: > >> #0: ffff88807d295298 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_lock= include/linux/mmap_lock.h:117 [inline] > >> #0: ffff88807d295298 (&mm->mmap_lock){++++}-{3:3}, at: do_user_addr_f= ault arch/x86/mm/fault.c:1358 [inline] > >> #0: ffff88807d295298 (&mm->mmap_lock){++++}-{3:3}, at: handle_page_fa= ult arch/x86/mm/fault.c:1498 [inline] > >> #0: ffff88807d295298 (&mm->mmap_lock){++++}-{3:3}, at: exc_page_fault= +0x558/0x8a0 arch/x86/mm/fault.c:1554 > >> 2 locks held by syz-executor359/5571: > >> #0: ffff88807838a5e8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x= 254/0x2f0 fs/file.c:1046 > >> #1: ffff88801d868460 (sb_writers#9){.+.+}-{0:0}, at: vfs_write+0x26d/= 0xbb0 fs/read_write.c:580 > >> 1 lock held by syz-executor359/5575: > >> #0: ffff88807d295298 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_loc= k include/linux/mmap_lock.h:71 [inline] > >> #0: ffff88807d295298 (&mm->mmap_lock){++++}-{3:3}, at: do_mbind mm/me= mpolicy.c:1312 [inline] > >> #0: ffff88807d295298 (&mm->mmap_lock){++++}-{3:3}, at: kernel_mbind m= m/mempolicy.c:1485 [inline] > >> #0: ffff88807d295298 (&mm->mmap_lock){++++}-{3:3}, at: __do_sys_mbind= mm/mempolicy.c:1559 [inline] > >> #0: ffff88807d295298 (&mm->mmap_lock){++++}-{3:3}, at: __se_sys_mbind= +0x47d/0x9c0 mm/mempolicy.c:1555 > >> 1 lock held by syz-executor359/5572: > >> #0: ffff88807d1dc098 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_lock= include/linux/mmap_lock.h:117 [inline] > >> #0: ffff88807d1dc098 (&mm->mmap_lock){++++}-{3:3}, at: do_user_addr_f= ault arch/x86/mm/fault.c:1358 [inline] > >> #0: ffff88807d1dc098 (&mm->mmap_lock){++++}-{3:3}, at: handle_page_fa= ult arch/x86/mm/fault.c:1498 [inline] > >> #0: ffff88807d1dc098 (&mm->mmap_lock){++++}-{3:3}, at: exc_page_fault= +0x558/0x8a0 arch/x86/mm/fault.c:1554 > >> 2 locks held by syz-executor359/5573: > >> #0: ffff888026d84d68 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x= 254/0x2f0 fs/file.c:1046 > >> #1: ffff88807b6ac460 (sb_writers#9){.+.+}-{0:0}, at: vfs_write+0x26d/= 0xbb0 fs/read_write.c:580 > >> 1 lock held by syz-executor359/5576: > >> #0: ffff88807d1dc098 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_loc= k include/linux/mmap_lock.h:71 [inline] > >> #0: ffff88807d1dc098 (&mm->mmap_lock){++++}-{3:3}, at: do_mbind mm/me= mpolicy.c:1312 [inline] > >> #0: ffff88807d1dc098 (&mm->mmap_lock){++++}-{3:3}, at: kernel_mbind m= m/mempolicy.c:1485 [inline] > >> #0: ffff88807d1dc098 (&mm->mmap_lock){++++}-{3:3}, at: __do_sys_mbind= mm/mempolicy.c:1559 [inline] > >> #0: ffff88807d1dc098 (&mm->mmap_lock){++++}-{3:3}, at: __se_sys_mbind= +0x47d/0x9c0 mm/mempolicy.c:1555 > >> 3 locks held by kworker/u4:3/5614: > >> #0: ffff8881451bb938 ((wq_completion)writeback){+.+.}-{0:0}, at: proc= ess_one_work+0x77f/0x13a0 > >> #1: ffffc90004defd20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{= 0:0}, at: process_one_work+0x7c6/0x13a0 kernel/workqueue.c:2365 > >> #2: ffff88807b6ac0e0 (&type->s_umount_key#43){++++}-{3:3}, at: tryloc= k_super+0x1f/0xf0 fs/super.c:414 > >> 3 locks held by kworker/u4:5/6087: > >> #0: ffff8881451bb938 ((wq_completion)writeback){+.+.}-{0:0}, at: proc= ess_one_work+0x77f/0x13a0 > >> #1: ffffc900055b7d20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{= 0:0}, at: process_one_work+0x7c6/0x13a0 kernel/workqueue.c:2365 > >> #2: ffff888148d0a0e0 (&type->s_umount_key#43){++++}-{3:3}, at: tryloc= k_super+0x1f/0xf0 fs/super.c:414 > >> 1 lock held by syz-executor359/12461: > >> #0: ffffffff8d12d1f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funne= l_lock kernel/rcu/tree_exp.h:293 [inline] > >> #0: ffffffff8d12d1f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchroni= ze_rcu_expedited+0x3a3/0x890 kernel/rcu/tree_exp.h:989 > >> > >> =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D > >> > >> NMI backtrace for cpu 0 > >> CPU: 0 PID: 28 Comm: khungtaskd Not tainted 6.2.0-syzkaller-10827-g489= fa31ea873 #0 > >> Hardware name: Google Google Compute Engine/Google Compute Engine, BIO= S Google 02/16/2023 > >> Call Trace: > >> > >> __dump_stack lib/dump_stack.c:88 [inline] > >> dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106 > >> nmi_cpu_backtrace+0x4e5/0x560 lib/nmi_backtrace.c:113 > >> nmi_trigger_cpumask_backtrace+0x1b4/0x410 lib/nmi_backtrace.c:62 > >> trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] > >> check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] > >> watchdog+0x1024/0x1070 kernel/hung_task.c:379 > >> kthread+0x270/0x300 kernel/kthread.c:376 > >> ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 > >> > >> Sending NMI from CPU 0 to CPUs 1: > >> NMI backtrace for cpu 1 > >> CPU: 1 PID: 6343 Comm: kworker/u4:9 Not tainted 6.2.0-syzkaller-10827-= g489fa31ea873 #0 > >> Hardware name: Google Google Compute Engine/Google Compute Engine, BIO= S Google 02/16/2023 > >> Workqueue: events_unbound toggle_allocation_gate > >> RIP: 0010:rcu_sync_is_idle include/linux/rcu_sync.h:36 [inline] > >> RIP: 0010:percpu_up_read include/linux/percpu-rwsem.h:105 [inline] > >> RIP: 0010:cpus_read_unlock+0x5f/0x130 kernel/cpu.c:322 > >> Code: 85 db 74 1b e8 c2 4f 20 00 89 c3 31 ff 89 c6 e8 87 23 39 00 85 > > db 74 5b e8 ce 1f 39 00 eb 05 e8 c7 1f 39 00 8b 1d 41 be a8 0b <31> ff > > 89 de e8 68 23 39 00 85 db 0f 85 8c 00 00 00 e8 ab 1f 39 00 > >> RSP: 0018:ffffc90005757b70 EFLAGS: 00000293 > >> RAX: ffffffff81538cb2 RBX: 0000000000000000 RCX: ffff888028643a80 > >> RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 > >> RBP: ffffc90005757c50 R08: ffffffff81538ca9 R09: fffffbfff1ce8d2e > >> R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000 > >> R13: 1ffff1104779cc03 R14: 0000000000000000 R15: 1ffff92000aeaf70 > >> FS: 0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000= 000000 > >> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > >> CR2: 00007ffd6fdf0bb8 CR3: 000000000cf30000 CR4: 00000000003506e0 > >> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > >> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > >> Call Trace: > >> > >> toggle_allocation_gate+0xb5/0x250 mm/kfence/core.c:799 > >> process_one_work+0x915/0x13a0 kernel/workqueue.c:2390 > >> worker_thread+0xa63/0x1210 kernel/workqueue.c:2537 > >> kthread+0x270/0x300 kernel/kthread.c:376 > >> ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 > >> > >> > >> > >> --- > >> This report is generated by a bot. It may contain errors. > >> See https://goo.gl/tpsmEJ for more information about syzbot. > >> syzbot engineers can be reached at syzkaller@googlegroups.com. > >> > >> syzbot will keep track of this issue. See: > >> https://goo.gl/tpsmEJ#status for how to communicate with syzbot. > >> syzbot can test patches for this issue, for details see: > >> https://goo.gl/tpsmEJ#testing-patches