bisecting cause commit starting from 8ee15f3248660f85102a47410079d408615723d4 building syzkaller on c402d8f1aa5d2fdc219d2155fa467fb7f02321a5 testing commit 8ee15f3248660f85102a47410079d408615723d4 with gcc (GCC) 8.1.0 run #0: crashed: INFO: task hung in do_exit run #1: crashed: INFO: task hung in do_exit run #2: crashed: INFO: task hung in do_exit run #3: OK run #4: OK run #5: OK run #6: OK run #7: OK run #8: OK run #9: OK testing release v5.0 testing commit 1c163f4c7b3f621efff9b28a47abb36f7378d783 with gcc (GCC) 8.1.0 run #0: crashed: INFO: task hung in do_exit run #1: crashed: INFO: task hung in do_exit run #2: crashed: INFO: task hung in do_exit run #3: crashed: INFO: task hung in do_exit run #4: OK run #5: OK run #6: OK run #7: OK run #8: OK run #9: OK testing release v4.20 testing commit 8fe28cb58bcb235034b64cbbb7550a8a43fd88be with gcc (GCC) 8.1.0 run #0: crashed: INFO: task hung in do_exit run #1: crashed: INFO: task hung in do_exit run #2: crashed: INFO: task hung in do_exit run #3: crashed: INFO: task hung in do_exit run #4: crashed: INFO: task hung in do_exit run #5: OK run #6: OK run #7: OK run #8: OK run #9: OK testing release v4.19 testing commit 84df9525b0c27f3ebc2ebb1864fa62a97fdedb7d with gcc (GCC) 8.1.0 run #0: crashed: INFO: task hung in do_exit run #1: crashed: INFO: task hung in do_exit run #2: crashed: INFO: task hung in do_exit run #3: crashed: INFO: task hung in do_exit run #4: OK run #5: OK run #6: OK run #7: OK run #8: OK run #9: OK testing release v4.18 testing commit 94710cac0ef4ee177a63b5227664b38c95bbf703 with gcc (GCC) 8.1.0 run #0: crashed: INFO: task hung in do_exit run #1: crashed: INFO: task hung in do_exit run #2: crashed: INFO: task hung in do_exit run #3: crashed: INFO: task hung in do_exit run #4: OK run #5: OK run #6: OK run #7: OK run #8: OK run #9: OK testing release v4.17 testing commit 29dcea88779c856c7dc92040a0c01233263101d4 with gcc (GCC) 8.1.0 run #0: crashed: INFO: task hung in do_exit run #1: crashed: INFO: task hung in do_exit run #2: crashed: INFO: task hung in do_exit run #3: crashed: INFO: task hung in do_exit run #4: OK run #5: OK run #6: OK run #7: OK run #8: OK run #9: OK testing release v4.16 testing commit 0adb32858b0bddf4ada5f364a84ed60b196dbcda with gcc (GCC) 8.1.0 run #0: crashed: INFO: task hung in do_exit run #1: crashed: INFO: task hung in do_exit run #2: crashed: INFO: task hung in do_exit run #3: crashed: INFO: task hung in do_exit run #4: crashed: INFO: task hung in do_exit run #5: OK run #6: OK run #7: OK run #8: OK run #9: OK testing release v4.15 testing commit d8a5b80568a9cb66810e75b182018e9edb68e8ff with gcc (GCC) 8.1.0 run #0: crashed: INFO: task hung in khugepaged run #1: crashed: INFO: task hung in khugepaged run #2: OK run #3: OK run #4: OK run #5: OK run #6: OK run #7: OK run #8: OK run #9: OK testing release v4.14 testing commit bebc6082da0a9f5d47a1ea2edc099bf671058bd4 with gcc (GCC) 8.1.0 run #0: crashed: INFO: task hung in khugepaged run #1: crashed: INFO: task hung in khugepaged run #2: crashed: INFO: task hung in khugepaged run #3: crashed: INFO: task hung in khugepaged run #4: crashed: INFO: task hung in khugepaged run #5: OK run #6: crashed: INFO: task hung in khugepaged run #7: OK run #8: OK run #9: OK testing release v4.13 testing commit 569dbb88e80deb68974ef6fdd6a13edb9d686261 with gcc (GCC) 8.1.0 all runs: OK # git bisect start v4.14 v4.13 Bisecting: 7300 revisions left to test after this (roughly 13 steps) [15d8ffc96464f6571ecf22043c45fad659f11bdd] Merge tag 'mmc-v4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc testing commit 15d8ffc96464f6571ecf22043c45fad659f11bdd with gcc (GCC) 8.1.0 run #0: basic kernel testing failed: failed to copy test binary to VM: failed to run ["scp" "-P" "22" "-F" "/dev/null" "-o" "UserKnownHostsFile=/dev/null" "-o" "BatchMode=yes" "-o" "IdentitiesOnly=yes" "-o" "StrictHostKeyChecking=no" "-o" "ConnectTimeout=10" "-i" "/syzkaller/jobs/linux/workdir/image/key" "/syzkaller/jobs/linux/gopath/src/github.com/google/syzkaller/bin/linux_amd64/syz-executor" "root@10.128.10.9:./syz-executor"]: exit status 1 ssh: connect to host 10.128.10.9 port 22: Connection timed out lost connection run #1: basic kernel testing failed: failed to copy test binary to VM: failed to run ["scp" "-P" "22" "-F" "/dev/null" "-o" "UserKnownHostsFile=/dev/null" "-o" "BatchMode=yes" "-o" "IdentitiesOnly=yes" "-o" "StrictHostKeyChecking=no" "-o" "ConnectTimeout=10" "-i" "/syzkaller/jobs/linux/workdir/image/key" "/syzkaller/jobs/linux/workdir/repro.prog" "root@10.128.0.142:./repro.prog"]: exit status 1 Connection timed out during banner exchange lost connection run #2: basic kernel testing failed: failed to copy test binary to VM: timedout ["scp" "-P" "22" "-F" "/dev/null" "-o" "UserKnownHostsFile=/dev/null" "-o" "BatchMode=yes" "-o" "IdentitiesOnly=yes" "-o" "StrictHostKeyChecking=no" "-o" "ConnectTimeout=10" "-i" "/syzkaller/jobs/linux/workdir/image/key" "/syzkaller/jobs/linux/gopath/src/github.com/google/syzkaller/bin/linux_amd64/syz-executor" "root@10.128.10.5:./syz-executor"] run #3: basic kernel testing failed: failed to copy test binary to VM: timedout ["scp" "-P" "22" "-F" "/dev/null" "-o" "UserKnownHostsFile=/dev/null" "-o" "BatchMode=yes" "-o" "IdentitiesOnly=yes" "-o" "StrictHostKeyChecking=no" "-o" "ConnectTimeout=10" "-i" "/syzkaller/jobs/linux/workdir/image/key" "/syzkaller/jobs/linux/gopath/src/github.com/google/syzkaller/bin/linux_amd64/syz-executor" "root@10.128.0.68:./syz-executor"] Warning: Permanently added '10.128.0.68' (ECDSA) to the list of known hosts. run #4: basic kernel testing failed: failed to copy test binary to VM: timedout ["scp" "-P" "22" "-F" "/dev/null" "-o" "UserKnownHostsFile=/dev/null" "-o" "BatchMode=yes" "-o" "IdentitiesOnly=yes" "-o" "StrictHostKeyChecking=no" "-o" "ConnectTimeout=10" "-i" "/syzkaller/jobs/linux/workdir/image/key" "/syzkaller/jobs/linux/gopath/src/github.com/google/syzkaller/bin/linux_amd64/syz-executor" "root@10.128.0.175:./syz-executor"] Warning: Permanently added '10.128.0.175' (ECDSA) to the list of known hosts. run #5: basic kernel testing failed: failed to copy test binary to VM: timedout ["scp" "-P" "22" "-F" "/dev/null" "-o" "UserKnownHostsFile=/dev/null" "-o" "BatchMode=yes" "-o" "IdentitiesOnly=yes" "-o" "StrictHostKeyChecking=no" "-o" "ConnectTimeout=10" "-i" "/syzkaller/jobs/linux/workdir/image/key" "/syzkaller/jobs/linux/gopath/src/github.com/google/syzkaller/bin/linux_amd64/syz-executor" "root@10.128.10.15:./syz-executor"] Warning: Permanently added '10.128.10.15' (ECDSA) to the list of known hosts. run #6: basic kernel testing failed: failed to copy test binary to VM: timedout ["scp" "-P" "22" "-F" "/dev/null" "-o" "UserKnownHostsFile=/dev/null" "-o" "BatchMode=yes" "-o" "IdentitiesOnly=yes" "-o" "StrictHostKeyChecking=no" "-o" "ConnectTimeout=10" "-i" "/syzkaller/jobs/linux/workdir/image/key" "/syzkaller/jobs/linux/gopath/src/github.com/google/syzkaller/bin/linux_amd64/syz-executor" "root@10.128.1.45:./syz-executor"] Warning: Permanently added '10.128.1.45' (ECDSA) to the list of known hosts. run #7: basic kernel testing failed: failed to copy test binary to VM: timedout ["scp" "-P" "22" "-F" "/dev/null" "-o" "UserKnownHostsFile=/dev/null" "-o" "BatchMode=yes" "-o" "IdentitiesOnly=yes" "-o" "StrictHostKeyChecking=no" "-o" "ConnectTimeout=10" "-i" "/syzkaller/jobs/linux/workdir/image/key" "/syzkaller/jobs/linux/gopath/src/github.com/google/syzkaller/bin/linux_amd64/syz-executor" "root@10.128.1.52:./syz-executor"] Warning: Permanently added '10.128.1.52' (ECDSA) to the list of known hosts. run #8: basic kernel testing failed: failed to copy test binary to VM: timedout ["scp" "-P" "22" "-F" "/dev/null" "-o" "UserKnownHostsFile=/dev/null" "-o" "BatchMode=yes" "-o" "IdentitiesOnly=yes" "-o" "StrictHostKeyChecking=no" "-o" "ConnectTimeout=10" "-i" "/syzkaller/jobs/linux/workdir/image/key" "/syzkaller/jobs/linux/gopath/src/github.com/google/syzkaller/bin/linux_amd64/syz-executor" "root@10.128.10.8:./syz-executor"] Warning: Permanently added '10.128.10.8' (ECDSA) to the list of known hosts. run #9: basic kernel testing failed: failed to copy test binary to VM: timedout ["scp" "-P" "22" "-F" "/dev/null" "-o" "UserKnownHostsFile=/dev/null" "-o" "BatchMode=yes" "-o" "IdentitiesOnly=yes" "-o" "StrictHostKeyChecking=no" "-o" "ConnectTimeout=10" "-i" "/syzkaller/jobs/linux/workdir/image/key" "/syzkaller/jobs/linux/gopath/src/github.com/google/syzkaller/bin/linux_amd64/syz-executor" "root@10.128.0.129:./syz-executor"] Warning: Permanently added '10.128.0.129' (ECDSA) to the list of known hosts. # git bisect skip 15d8ffc96464f6571ecf22043c45fad659f11bdd Bisecting: 7300 revisions left to test after this (roughly 13 steps) [ace743214ea205c7d433562c5fa24e33bdfda7ab] net/mlx5e: Fix erroneous freeing of encap header buffer testing commit ace743214ea205c7d433562c5fa24e33bdfda7ab with gcc (GCC) 8.1.0 run #0: crashed: INFO: task hung in khugepaged run #1: crashed: INFO: task hung in khugepaged run #2: crashed: INFO: task hung in khugepaged run #3: crashed: INFO: task hung in khugepaged run #4: crashed: INFO: task hung in khugepaged run #5: OK run #6: OK run #7: OK run #8: OK run #9: OK # git bisect bad ace743214ea205c7d433562c5fa24e33bdfda7ab Bisecting: 6370 revisions left to test after this (roughly 13 steps) [aae3dbb4776e7916b6cd442d00159bea27a695c1] Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next testing commit aae3dbb4776e7916b6cd442d00159bea27a695c1 with gcc (GCC) 8.1.0 run #0: basic kernel testing failed: failed to copy test binary to VM: failed to run ["scp" "-P" "22" "-F" "/dev/null" "-o" "UserKnownHostsFile=/dev/null" "-o" "BatchMode=yes" "-o" "IdentitiesOnly=yes" "-o" "StrictHostKeyChecking=no" "-o" "ConnectTimeout=10" "-i" "/syzkaller/jobs/linux/workdir/image/key" "/syzkaller/jobs/linux/gopath/src/github.com/google/syzkaller/bin/linux_amd64/syz-executor" "root@10.128.1.39:./syz-executor"]: exit status 1 ssh: connect to host 10.128.1.39 port 22: Connection timed out lost connection run #1: basic kernel testing failed: failed to copy test binary to VM: timedout ["scp" "-P" "22" "-F" "/dev/null" "-o" "UserKnownHostsFile=/dev/null" "-o" "BatchMode=yes" "-o" "IdentitiesOnly=yes" "-o" "StrictHostKeyChecking=no" "-o" "ConnectTimeout=10" "-i" "/syzkaller/jobs/linux/workdir/image/key" "/syzkaller/jobs/linux/gopath/src/github.com/google/syzkaller/bin/linux_amd64/syz-executor" "root@10.128.0.106:./syz-executor"] Warning: Permanently added '10.128.0.106' (ECDSA) to the list of known hosts. run #2: basic kernel testing failed: failed to copy test binary to VM: timedout ["scp" "-P" "22" "-F" "/dev/null" "-o" "UserKnownHostsFile=/dev/null" "-o" "BatchMode=yes" "-o" "IdentitiesOnly=yes" "-o" "StrictHostKeyChecking=no" "-o" "ConnectTimeout=10" "-i" "/syzkaller/jobs/linux/workdir/image/key" "/syzkaller/jobs/linux/gopath/src/github.com/google/syzkaller/bin/linux_amd64/syz-executor" "root@10.128.0.20:./syz-executor"] Warning: Permanently added '10.128.0.20' (ECDSA) to the list of known hosts. run #3: basic kernel testing failed: failed to copy test binary to VM: timedout ["scp" "-P" "22" "-F" "/dev/null" "-o" "UserKnownHostsFile=/dev/null" "-o" "BatchMode=yes" "-o" "IdentitiesOnly=yes" "-o" "StrictHostKeyChecking=no" "-o" "ConnectTimeout=10" "-i" "/syzkaller/jobs/linux/workdir/image/key" "/syzkaller/jobs/linux/gopath/src/github.com/google/syzkaller/bin/linux_amd64/syz-executor" "root@10.128.0.243:./syz-executor"] Warning: Permanently added '10.128.0.243' (ECDSA) to the list of known hosts. run #4: basic kernel testing failed: failed to copy test binary to VM: timedout ["scp" "-P" "22" "-F" "/dev/null" "-o" "UserKnownHostsFile=/dev/null" "-o" "BatchMode=yes" "-o" "IdentitiesOnly=yes" "-o" "StrictHostKeyChecking=no" "-o" "ConnectTimeout=10" "-i" "/syzkaller/jobs/linux/workdir/image/key" "/syzkaller/jobs/linux/gopath/src/github.com/google/syzkaller/bin/linux_amd64/syz-execprog" "root@10.128.1.36:./syz-execprog"] Warning: Permanently added '10.128.1.36' (ECDSA) to the list of known hosts. run #5: basic kernel testing failed: failed to copy test binary to VM: timedout ["scp" "-P" "22" "-F" "/dev/null" "-o" "UserKnownHostsFile=/dev/null" "-o" "BatchMode=yes" "-o" "IdentitiesOnly=yes" "-o" "StrictHostKeyChecking=no" "-o" "ConnectTimeout=10" "-i" "/syzkaller/jobs/linux/workdir/image/key" "/syzkaller/jobs/linux/gopath/src/github.com/google/syzkaller/bin/linux_amd64/syz-executor" "root@10.128.0.249:./syz-executor"] Warning: Permanently added '10.128.0.249' (ECDSA) to the list of known hosts. run #6: basic kernel testing failed: failed to copy test binary to VM: timedout ["scp" "-P" "22" "-F" "/dev/null" "-o" "UserKnownHostsFile=/dev/null" "-o" "BatchMode=yes" "-o" "IdentitiesOnly=yes" "-o" "StrictHostKeyChecking=no" "-o" "ConnectTimeout=10" "-i" "/syzkaller/jobs/linux/workdir/image/key" "/syzkaller/jobs/linux/gopath/src/github.com/google/syzkaller/bin/linux_amd64/syz-executor" "root@10.128.1.28:./syz-executor"] Warning: Permanently added '10.128.1.28' (ECDSA) to the list of known hosts. run #7: basic kernel testing failed: failed to copy test binary to VM: timedout ["scp" "-P" "22" "-F" "/dev/null" "-o" "UserKnownHostsFile=/dev/null" "-o" "BatchMode=yes" "-o" "IdentitiesOnly=yes" "-o" "StrictHostKeyChecking=no" "-o" "ConnectTimeout=10" "-i" "/syzkaller/jobs/linux/workdir/image/key" "/syzkaller/jobs/linux/gopath/src/github.com/google/syzkaller/bin/linux_amd64/syz-executor" "root@10.128.0.221:./syz-executor"] run #8: basic kernel testing failed: failed to copy test binary to VM: timedout ["scp" "-P" "22" "-F" "/dev/null" "-o" "UserKnownHostsFile=/dev/null" "-o" "BatchMode=yes" "-o" "IdentitiesOnly=yes" "-o" "StrictHostKeyChecking=no" "-o" "ConnectTimeout=10" "-i" "/syzkaller/jobs/linux/workdir/image/key" "/syzkaller/jobs/linux/gopath/src/github.com/google/syzkaller/bin/linux_amd64/syz-execprog" "root@10.128.0.114:./syz-execprog"] Warning: Permanently added '10.128.0.114' (ECDSA) to the list of known hosts. run #9: basic kernel testing failed: failed to copy test binary to VM: timedout ["scp" "-P" "22" "-F" "/dev/null" "-o" "UserKnownHostsFile=/dev/null" "-o" "BatchMode=yes" "-o" "IdentitiesOnly=yes" "-o" "StrictHostKeyChecking=no" "-o" "ConnectTimeout=10" "-i" "/syzkaller/jobs/linux/workdir/image/key" "/syzkaller/jobs/linux/gopath/src/github.com/google/syzkaller/bin/linux_amd64/syz-executor" "root@10.128.0.5:./syz-executor"] Warning: Permanently added '10.128.0.5' (ECDSA) to the list of known hosts. # git bisect skip aae3dbb4776e7916b6cd442d00159bea27a695c1 Bisecting: 6370 revisions left to test after this (roughly 13 steps) [f5808ac158f2b16b686a3d3c0879c5d6048aba14] leds: gpio: Allow LED to retain state at shutdown testing commit f5808ac158f2b16b686a3d3c0879c5d6048aba14 with gcc (GCC) 8.1.0 run #0: crashed: INFO: task hung in khugepaged run #1: OK run #2: crashed: INFO: task hung in do_exit run #3: OK run #4: OK run #5: OK run #6: OK run #7: OK run #8: OK run #9: OK # git bisect bad f5808ac158f2b16b686a3d3c0879c5d6048aba14 Bisecting: 8 revisions left to test after this (roughly 3 steps) [15201b5de9d62fd6ece51ba9005c441d588fcb94] dt-bindings: leds: add pca955x testing commit 15201b5de9d62fd6ece51ba9005c441d588fcb94 with gcc (GCC) 8.1.0 all runs: OK # git bisect good 15201b5de9d62fd6ece51ba9005c441d588fcb94 Bisecting: 3 revisions left to test after this (roughly 2 steps) [85775013ec49b3d114adfbd618d721247bf1b431] leds: lp5562: make several arrays static const testing commit 85775013ec49b3d114adfbd618d721247bf1b431 with gcc (GCC) 8.1.0 run #0: crashed: INFO: task hung in khugepaged run #1: crashed: INFO: task hung in khugepaged run #2: OK run #3: OK run #4: OK run #5: OK run #6: OK run #7: OK run #8: OK run #9: OK # git bisect bad 85775013ec49b3d114adfbd618d721247bf1b431 Bisecting: 1 revision left to test after this (roughly 1 step) [17224244bbbe2ac91bc2645b5198f742a63e1d82] leds: aat1290: make array max_mm_current_percent static const testing commit 17224244bbbe2ac91bc2645b5198f742a63e1d82 with gcc (GCC) 8.1.0 run #0: crashed: INFO: task hung in khugepaged run #1: crashed: INFO: task hung in khugepaged run #2: crashed: INFO: task hung in khugepaged run #3: OK run #4: OK run #5: OK run #6: OK run #7: OK run #8: OK run #9: OK # git bisect bad 17224244bbbe2ac91bc2645b5198f742a63e1d82 Bisecting: 0 revisions left to test after this (roughly 1 step) [390c97dc6e346b65df61c18fade67577896382fd] leds: pca955x: Prevent crippled LED device name testing commit 390c97dc6e346b65df61c18fade67577896382fd with gcc (GCC) 8.1.0 run #0: crashed: INFO: task hung in do_exit 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 # git bisect bad 390c97dc6e346b65df61c18fade67577896382fd Bisecting: 0 revisions left to test after this (roughly 0 steps) [430e48ecf31f4f897047f22e02abdfa75730cad8] leds: lm3533: constify attribute_group structure testing commit 430e48ecf31f4f897047f22e02abdfa75730cad8 with gcc (GCC) 8.1.0 run #0: crashed: INFO: task hung in khugepaged 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 # git bisect bad 430e48ecf31f4f897047f22e02abdfa75730cad8 430e48ecf31f4f897047f22e02abdfa75730cad8 is the first bad commit commit 430e48ecf31f4f897047f22e02abdfa75730cad8 Author: Amitoj Kaur Chawla Date: Thu Aug 10 12:28:09 2017 -0400 leds: lm3533: constify attribute_group structure Functions working with attribute_groups provided by work with const attribute_group. These attribute_group structures do not change at runtime so mark them as const. File size before: text data bss dec hex filename 8272 4608 64 12944 3290 drivers/leds/leds-lm3533.o File size after: text data bss dec hex filename 8368 4512 64 12944 3290 drivers/leds/leds-lm3533.o This change was made with the help of Coccinelle. Signed-off-by: Amitoj Kaur Chawla Acked-by: Pavel Machek Signed-off-by: Jacek Anaszewski :040000 040000 aab39d2abe08a67a36f0165183565af14587411a 11bf90bf48948d694307a62833f4cb371351b25a M drivers revisions tested: 19, total time: 4h58m16.415467301s (build: 1h42m34.625842772s, test: 3h9m25.098393969s) first bad commit: 430e48ecf31f4f897047f22e02abdfa75730cad8 leds: lm3533: constify attribute_group structure cc: ["amitoj1606@gmail.com" "jacek.anaszewski@gmail.com" "linux-kernel@vger.kernel.org" "linux-leds@vger.kernel.org" "pavel@ucw.cz" "rpurdie@rpsys.net"] crash: INFO: task hung in khugepaged kworker/dying (28) used greatest stack depth: 15480 bytes left INFO: task khugepaged:1016 blocked for more than 140 seconds. Not tainted 4.13.0-rc1+ #1 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. khugepaged D23000 1016 2 0x00000000 Call Trace: context_switch kernel/sched/core.c:2771 [inline] __schedule+0x818/0x1fa0 kernel/sched/core.c:3332 schedule+0x109/0x440 kernel/sched/core.c:3391 rwsem_down_read_failed+0x3fe/0x650 kernel/locking/rwsem-xadd.c:261 call_rwsem_down_read_failed+0x18/0x30 arch/x86/lib/rwsem.S:94 __down_read arch/x86/include/asm/rwsem.h:65 [inline] down_read+0xa0/0x150 kernel/locking/rwsem.c:25 khugepaged_scan_mm_slot mm/khugepaged.c:1676 [inline] khugepaged_do_scan mm/khugepaged.c:1809 [inline] khugepaged+0x988/0x12f0 mm/khugepaged.c:1854 kthread+0x338/0x400 kernel/kthread.c:231 ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:425 Showing all locks held in the system: 2 locks held by khungtaskd/1009: #0: (rcu_read_lock){......}, at: [] check_hung_uninterruptible_tasks kernel/hung_task.c:175 [inline] #0: (rcu_read_lock){......}, at: [] watchdog+0x19d/0xba0 kernel/hung_task.c:249 #1: (tasklist_lock){.+.+..}, at: [] debug_show_all_locks+0xde/0x340 kernel/locking/lockdep.c:4417 1 lock held by khugepaged/1016: #0: (&mm->mmap_sem){++++++}, at: [] khugepaged_scan_mm_slot mm/khugepaged.c:1676 [inline] #0: (&mm->mmap_sem){++++++}, at: [] khugepaged_do_scan mm/khugepaged.c:1809 [inline] #0: (&mm->mmap_sem){++++++}, at: [] khugepaged+0x988/0x12f0 mm/khugepaged.c:1854 2 locks held by getty/6459: #0: (&tty->ldisc_sem){++++++}, at: [] ldsem_down_read+0x2d/0x40 drivers/tty/tty_ldsem.c:367 #1: (&ldata->atomic_read_lock){+.+...}, at: [] n_tty_read+0x2e9/0x19d0 drivers/tty/n_tty.c:2133 2 locks held by getty/6460: #0: (&tty->ldisc_sem){++++++}, at: [] ldsem_down_read+0x2d/0x40 drivers/tty/tty_ldsem.c:367 #1: (&ldata->atomic_read_lock){+.+...}, at: [] n_tty_read+0x2e9/0x19d0 drivers/tty/n_tty.c:2133 2 locks held by getty/6461: #0: (&tty->ldisc_sem){++++++}, at: [] ldsem_down_read+0x2d/0x40 drivers/tty/tty_ldsem.c:367 #1: (&ldata->atomic_read_lock){+.+...}, at: [] n_tty_read+0x2e9/0x19d0 drivers/tty/n_tty.c:2133 2 locks held by getty/6462: #0: (&tty->ldisc_sem){++++++}, at: [] ldsem_down_read+0x2d/0x40 drivers/tty/tty_ldsem.c:367 #1: (&ldata->atomic_read_lock){+.+...}, at: [] n_tty_read+0x2e9/0x19d0 drivers/tty/n_tty.c:2133 2 locks held by getty/6463: #0: (&tty->ldisc_sem){++++++}, at: [] ldsem_down_read+0x2d/0x40 drivers/tty/tty_ldsem.c:367 #1: (&ldata->atomic_read_lock){+.+...}, at: [] n_tty_read+0x2e9/0x19d0 drivers/tty/n_tty.c:2133 2 locks held by getty/6464: #0: (&tty->ldisc_sem){++++++}, at: [] ldsem_down_read+0x2d/0x40 drivers/tty/tty_ldsem.c:367 #1: (&ldata->atomic_read_lock){+.+...}, at: [] n_tty_read+0x2e9/0x19d0 drivers/tty/n_tty.c:2133 2 locks held by getty/6465: #0: (&tty->ldisc_sem){++++++}, at: [] ldsem_down_read+0x2d/0x40 drivers/tty/tty_ldsem.c:367 #1: (&ldata->atomic_read_lock){+.+...}, at: [] n_tty_read+0x2e9/0x19d0 drivers/tty/n_tty.c:2133 1 lock held by syz-executor.3/5978: #0: (&mm->mmap_sem){++++++}, at: [] exit_mm kernel/exit.c:510 [inline] #0: (&mm->mmap_sem){++++++}, at: [] do_exit+0x44a/0x17d0 kernel/exit.c:852 1 lock held by syz-executor.3/5981: #0: (&mm->mmap_sem){++++++}, at: [] exit_mm kernel/exit.c:510 [inline] #0: (&mm->mmap_sem){++++++}, at: [] do_exit+0x44a/0x17d0 kernel/exit.c:852 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1009 Comm: khungtaskd Not tainted 4.13.0-rc1+ #1 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:16 [inline] dump_stack+0x145/0x1e1 lib/dump_stack.c:52 nmi_cpu_backtrace.cold.5+0x13/0xb2 lib/nmi_backtrace.c:102 nmi_trigger_cpumask_backtrace+0xf4/0x118 lib/nmi_backtrace.c:61 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37 trigger_all_cpu_backtrace include/linux/nmi.h:105 [inline] check_hung_task kernel/hung_task.c:132 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:190 [inline] watchdog+0x74d/0xba0 kernel/hung_task.c:249 kthread+0x338/0x400 kernel/kthread.c:231 ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:425 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 5989 Comm: syz-executor.3 Not tainted 4.13.0-rc1+ #1 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff88010defa2c0 task.stack: ffff880127190000 RIP: 0010:debug_lockdep_rcu_enabled+0x20/0x90 kernel/rcu/update.c:299 RSP: 0018:ffff880127197370 EFLAGS: 00000a07 RAX: dffffc0000000000 RBX: 1ffff10024e32e71 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 00000000000002eb RDI: ffffffff88bf7a74 RBP: ffff880127197370 R08: ffffffff817cdd5b R09: ffffffff89e98ec0 R10: ffff880127197860 R11: 0000000000000000 R12: ffffffff870ac9c0 R13: 0000000000000000 R14: ffffffff870ac9c0 R15: 00000000000002eb FS: 00007fe28fd0b700(0000) GS:ffff88012c000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff973c0f140 CR3: 0000000124726000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ___might_sleep+0x66/0x320 kernel/sched/core.c:5959 __might_sleep+0x93/0xb0 kernel/sched/core.c:5947 __mutex_lock_common kernel/locking/mutex.c:747 [inline] __mutex_lock+0x13d/0x18f0 kernel/locking/mutex.c:893 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 perf_mmap+0x59b/0x1830 kernel/events/core.c:5307 call_mmap include/linux/fs.h:1747 [inline] mmap_region+0xa1e/0x16d0 mm/mmap.c:1689 do_mmap+0x534/0x1170 mm/mmap.c:1467 do_mmap_pgoff include/linux/mm.h:2107 [inline] vm_mmap_pgoff+0x1c3/0x2b0 mm/util.c:333 SYSC_mmap_pgoff mm/mmap.c:1517 [inline] SyS_mmap_pgoff+0x411/0x710 mm/mmap.c:1475 SYSC_mmap arch/x86/kernel/sys_x86_64.c:98 [inline] SyS_mmap+0x16/0x20 arch/x86/kernel/sys_x86_64.c:89 entry_SYSCALL_64_fastpath+0x23/0xc2 RIP: 0033:0x458c29 RSP: 002b:00007fe28fd0ac78 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 0000000000458c29 RDX: 0000000000000000 RSI: 0000000000003000 RDI: 0000000020ffd000 RBP: 0000000000000082 R08: 0000000000000003 R09: 0000000000000000 R10: 0000000000001011 R11: 0000000000000246 R12: 00007fe28fd0b6d4 R13: 00000000004c4b5a R14: 00000000004d8780 R15: 00000000ffffffff Code: 00 66 2e 0f 1f 84 00 00 00 00 00 48 c7 c7 74 7a bf 88 55 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 89 e5 48 c1 ea 03 0f b6 14 02 <48> 89 f8 83 e0 07 83 c0 03 38 d0 7c 04 84 d2 75 4c 8b 15 7d 75