bisecting cause commit starting from e9919e11e219eaa5e8041b7b1a196839143e9125 building syzkaller on 609fb51750f5938bd47f9b78c3d7d8fb435d069c testing commit e9919e11e219eaa5e8041b7b1a196839143e9125 with gcc (GCC) 8.1.0 kernel signature: 81c7a464d583c5afa81836a36fefbffa696e4f75d4091d1426a05a009d43bc95 run #0: crashed: INFO: rcu detected stall in do_sys_open run #1: crashed: BUG: soft lockup in smp_call_function run #2: crashed: INFO: rcu detected stall in rtnl_newlink run #3: crashed: BUG: soft lockup in smp_call_function run #4: crashed: BUG: soft lockup in smp_call_function run #5: crashed: INFO: rcu detected stall in sys_clock_settime run #6: crashed: INFO: rcu detected stall in sys_clock_settime run #7: crashed: INFO: rcu detected stall in corrupted run #8: crashed: INFO: rcu detected stall in sys_clock_settime run #9: crashed: INFO: rcu detected stall in inet6_rtm_newaddr testing release v5.7 testing commit 3d77e6a8804abcc0504c904bd6e5cdf3a5cf8162 with gcc (GCC) 8.1.0 kernel signature: 172a04728572042192bf3451dbeb8dfe8a665da2eab2d1563cbd69dd6d434b08 run #0: crashed: INFO: rcu detected stall in sys_clock_settime run #1: crashed: INFO: rcu detected stall in sys_clock_settime run #2: crashed: INFO: rcu detected stall in sys_clock_settime run #3: crashed: INFO: rcu detected stall in sys_clock_settime run #4: crashed: INFO: rcu detected stall in sys_clock_settime run #5: crashed: BUG: soft lockup in smp_call_function run #6: crashed: BUG: soft lockup in smp_call_function run #7: crashed: BUG: soft lockup in smp_call_function run #8: crashed: no output from test machine run #9: crashed: no output from test machine testing release v5.6 testing commit 7111951b8d4973bda27ff663f2cf18b663d15b48 with gcc (GCC) 8.1.0 kernel signature: fe5745f1558b6f182446fdbe1e447e2d46b8f0c850bede332dfa69a5cd4b43e6 run #0: crashed: INFO: rcu detected stall in do_sys_open run #1: crashed: INFO: rcu detected stall in sys_clock_settime run #2: crashed: INFO: rcu detected stall in sys_clock_settime run #3: crashed: INFO: rcu detected stall in corrupted run #4: crashed: INFO: rcu detected stall in sys_clock_settime run #5: crashed: BUG: soft lockup in smp_call_function run #6: crashed: BUG: soft lockup in smp_call_function run #7: crashed: BUG: soft lockup in smp_call_function run #8: crashed: no output from test machine run #9: crashed: no output from test machine testing release v5.5 testing commit d5226fa6dbae0569ee43ecfc08bdcd6770fc4755 with gcc (GCC) 8.1.0 kernel signature: 72a2236f11bb255bbeb46ad2f385f7f5e58004f39993d6b6e87b7eec763ad485 all runs: crashed: BUG: sleeping function called from invalid context in cpus_read_lock testing release v5.4 testing commit 219d54332a09e8d8741c1e1982f5eae56099de85 with gcc (GCC) 8.1.0 kernel signature: 38e9806cecdd87f55b595912a2e3148a679ded32f9eeffa750857474391e30ef all runs: crashed: BUG: sleeping function called from invalid context in cpus_read_lock testing release v5.3 testing commit 4d856f72c10ecb060868ed10ff1b1453943fc6c8 with gcc (GCC) 8.1.0 kernel signature: e510919474a186cc034c0da48a1aec34a6ee650c0f5fc2011744eb2a7e2c15cd all runs: crashed: BUG: sleeping function called from invalid context in cpus_read_lock testing release v5.2 testing commit 0ecfebd2b52404ae0c54a878c872bb93363ada36 with gcc (GCC) 8.1.0 kernel signature: f173bf018be9e7df8d5ef4175f6ce8ceb2b66072a4fd3209082e9b7fb518f13d all runs: crashed: BUG: sleeping function called from invalid context in cpus_read_lock testing release v5.1 testing commit e93c9c99a629c61837d5a7fc2120cd2b6c70dbdd with gcc (GCC) 8.1.0 kernel signature: 8e71d0a77703f7f514faa6693b197c828f384b3686436f90e0d93cc9541cb066 run #0: crashed: INFO: rcu detected stall in rtnl_newlink run #1: crashed: INFO: rcu detected stall in sys_getdents run #2: crashed: INFO: rcu detected stall in sys_clock_settime run #3: crashed: INFO: rcu detected stall in smp_call_function run #4: crashed: INFO: rcu detected stall in sys_clock_settime run #5: crashed: BUG: soft lockup in smp_call_function run #6: crashed: BUG: soft lockup in smp_call_function run #7: crashed: BUG: soft lockup in smp_call_function run #8: crashed: BUG: soft lockup in smp_call_function run #9: crashed: INFO: rcu detected stall in linkwatch_event testing release v5.0 testing commit 1c163f4c7b3f621efff9b28a47abb36f7378d783 with gcc (GCC) 8.1.0 kernel signature: a4f88d857df0afa21aec1679d5b4ec2d668ed1dd86c45c1429ff571616a2d134 run #0: crashed: INFO: rcu detected stall in netlink_sendmsg run #1: crashed: INFO: rcu detected stall in inet6_rtm_newaddr run #2: crashed: INFO: rcu detected stall in sys_clock_settime run #3: crashed: INFO: rcu detected stall in sys_clock_settime run #4: crashed: BUG: soft lockup in smp_call_function run #5: crashed: BUG: soft lockup in smp_call_function run #6: crashed: BUG: soft lockup in smp_call_function run #7: crashed: INFO: rcu detected stall in smp_call_function run #8: crashed: no output from test machine run #9: crashed: BUG: soft lockup in smp_call_function testing release v4.20 testing commit 8fe28cb58bcb235034b64cbbb7550a8a43fd88be with gcc (GCC) 8.1.0 kernel signature: b56aca3e0b30348a9cc2abc95d8c94cf8f0052da20134674632c83f31d3c729d run #0: crashed: INFO: rcu detected stall in sys_clock_settime run #1: crashed: INFO: rcu detected stall in sys_clock_settime run #2: crashed: INFO: rcu detected stall in sys_clock_settime run #3: crashed: INFO: rcu detected stall in sys_clock_settime run #4: crashed: INFO: rcu detected stall in sys_clock_settime run #5: crashed: BUG: soft lockup in smp_call_function run #6: crashed: BUG: soft lockup in smp_call_function run #7: crashed: BUG: soft lockup in smp_call_function run #8: crashed: BUG: soft lockup in smp_call_function run #9: crashed: INFO: rcu detected stall in rtnl_newlink testing release v4.19 testing commit 84df9525b0c27f3ebc2ebb1864fa62a97fdedb7d with gcc (GCC) 8.1.0 kernel signature: 0e62f123594f1d57a2effcf6b350d823aae5db0e80cbc023f9a99f0b9880dec1 all runs: OK # git bisect start 8fe28cb58bcb235034b64cbbb7550a8a43fd88be 84df9525b0c27f3ebc2ebb1864fa62a97fdedb7d Bisecting: 7499 revisions left to test after this (roughly 13 steps) [ec9c166434595382be3babf266febf876327774d] Merge tag 'mips_fixes_4.20_1' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux testing commit ec9c166434595382be3babf266febf876327774d with gcc (GCC) 8.1.0 kernel signature: d33d7f1c593b75ca50d0d7015ef0607e1b6930ed3f477c9247cb29b3f636927a run #0: crashed: INFO: rcu detected stall in sys_clock_settime run #1: crashed: INFO: rcu detected stall in sys_clock_settime run #2: crashed: INFO: rcu detected stall in sys_clock_settime run #3: crashed: INFO: rcu detected stall in sys_clock_settime run #4: crashed: INFO: rcu detected stall in sys_clock_settime run #5: crashed: BUG: soft lockup in smp_call_function run #6: crashed: BUG: soft lockup in smp_call_function run #7: crashed: BUG: soft lockup in smp_call_function run #8: crashed: BUG: soft lockup in smp_call_function run #9: crashed: BUG: soft lockup in smp_call_function # git bisect bad ec9c166434595382be3babf266febf876327774d Bisecting: 3252 revisions left to test after this (roughly 12 steps) [50b825d7e87f4cff7070df6eb26390152bb29537] Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next testing commit 50b825d7e87f4cff7070df6eb26390152bb29537 with gcc (GCC) 8.1.0 kernel signature: 4f518b53c63843dcd51c2ae2a2cbf7d80f0083c57801a9023cb2ae4e2dee13a1 run #0: crashed: INFO: rcu detected stall in rtnl_newlink run #1: crashed: INFO: rcu detected stall in sys_clock_settime run #2: crashed: INFO: rcu detected stall in sys_clock_settime run #3: crashed: INFO: rcu detected stall in sys_clock_settime run #4: crashed: INFO: rcu detected stall in sys_clock_settime run #5: crashed: BUG: soft lockup in smp_call_function run #6: crashed: BUG: soft lockup in smp_call_function run #7: crashed: BUG: soft lockup in smp_call_function run #8: crashed: BUG: soft lockup in smp_call_function run #9: crashed: no output from test machine # git bisect bad 50b825d7e87f4cff7070df6eb26390152bb29537 Bisecting: 2120 revisions left to test after this (roughly 11 steps) [99e9acd85ccbdc8f5785f9e961d4956e96bd6aa5] Merge tag 'mlx5-updates-2018-10-17' of git://git.kernel.org/pub/scm/linux/kernel/git/saeed/linux testing commit 99e9acd85ccbdc8f5785f9e961d4956e96bd6aa5 with gcc (GCC) 8.1.0 kernel signature: 9945c9dc5d2b53e2c735cc8d99f7efb878430714593acfa194d2577da3844899 run #0: crashed: INFO: rcu detected stall in smp_call_function run #1: crashed: INFO: rcu detected stall in smp_call_function run #2: crashed: INFO: rcu detected stall in sys_clock_settime run #3: crashed: BUG: soft lockup in smp_call_function run #4: crashed: BUG: soft lockup in smp_call_function run #5: crashed: BUG: soft lockup in smp_call_function run #6: crashed: BUG: soft lockup in smp_call_function run #7: crashed: BUG: soft lockup in smp_call_function run #8: crashed: no output from test machine run #9: crashed: no output from test machine # git bisect bad 99e9acd85ccbdc8f5785f9e961d4956e96bd6aa5 Bisecting: 989 revisions left to test after this (roughly 10 steps) [d793fb46822ff7408a1767313ef6b12e811baa55] Merge tag 'wireless-drivers-next-for-davem-2018-10-02' of git://git.kernel.org/pub/scm/linux/kernel/git/kvalo/wireless-drivers-next testing commit d793fb46822ff7408a1767313ef6b12e811baa55 with gcc (GCC) 8.1.0 kernel signature: 0eaa6a5738dcd1521243b2b935059977f15f4e44f12a2f8d4b76e0e2c8e6cebd all runs: OK # git bisect good d793fb46822ff7408a1767313ef6b12e811baa55 Bisecting: 461 revisions left to test after this (roughly 9 steps) [071a234ad744ab9a1e9c948874d5f646a2964734] Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next testing commit 071a234ad744ab9a1e9c948874d5f646a2964734 with gcc (GCC) 8.1.0 kernel signature: e30eb99dec189c42238b1c7dd18eee54ca13e5fbaa72cb6a9afdd6c1ac252f54 run #0: crashed: INFO: rcu detected stall in sys_clock_settime run #1: crashed: INFO: rcu detected stall in sys_clock_settime run #2: crashed: INFO: rcu detected stall in sys_clock_settime run #3: crashed: INFO: rcu detected stall in sys_clock_settime run #4: crashed: INFO: rcu detected stall in sys_clock_settime run #5: crashed: INFO: rcu detected stall in sys_clock_settime run #6: crashed: BUG: soft lockup in smp_call_function run #7: crashed: BUG: soft lockup in smp_call_function run #8: crashed: BUG: soft lockup in smp_call_function run #9: crashed: BUG: soft lockup in smp_call_function # git bisect bad 071a234ad744ab9a1e9c948874d5f646a2964734 Bisecting: 275 revisions left to test after this (roughly 8 steps) [5580d810560da33804053ae3bca13110c9a8d5e8] Merge tag 'mt76-for-kvalo-2018-10-05' of https://github.com/nbd168/wireless testing commit 5580d810560da33804053ae3bca13110c9a8d5e8 with gcc (GCC) 8.1.0 kernel signature: 6e6469f24739e8e16920c98dfd6671d1a9a14b373d52ee4b51a0f58c88522f28 all runs: OK # git bisect good 5580d810560da33804053ae3bca13110c9a8d5e8 Bisecting: 137 revisions left to test after this (roughly 7 steps) [b245d32c995868879f361d252f32bb8a2ca33deb] net: sched: cls_u32: keep track of knodes count in tc_u_common testing commit b245d32c995868879f361d252f32bb8a2ca33deb with gcc (GCC) 8.1.0 kernel signature: 2e782969bb219b82fc36e9790a20bc1ea125f820e679fef3f2814dd604841463 run #0: crashed: INFO: rcu detected stall in rtnl_newlink run #1: crashed: INFO: rcu detected stall in sys_open run #2: crashed: INFO: rcu detected stall in sys_clock_settime run #3: crashed: INFO: rcu detected stall in sys_clock_settime run #4: crashed: INFO: rcu detected stall in sys_clock_settime run #5: crashed: INFO: rcu detected stall in sys_clock_settime run #6: crashed: INFO: rcu detected stall in sys_clock_settime run #7: crashed: BUG: soft lockup in smp_call_function run #8: crashed: BUG: soft lockup in smp_call_function run #9: crashed: INFO: rcu detected stall in sys_clock_settime # git bisect bad b245d32c995868879f361d252f32bb8a2ca33deb Bisecting: 68 revisions left to test after this (roughly 6 steps) [cc5f0eb2164f9aa11fe631f8d905192e0233e262] net: Move free of fib_metrics to helper testing commit cc5f0eb2164f9aa11fe631f8d905192e0233e262 with gcc (GCC) 8.1.0 kernel signature: 110eadc2eb2731c055081a54ed82b2d3abf04cb6703e222af5266eda9532bf26 run #0: crashed: INFO: rcu detected stall in netlink_sendmsg run #1: crashed: INFO: rcu detected stall in proc_reg_read run #2: crashed: INFO: rcu detected stall in sys_clock_settime run #3: crashed: INFO: rcu detected stall in sys_clock_settime run #4: crashed: INFO: rcu detected stall in sys_clock_settime run #5: crashed: BUG: soft lockup in smp_call_function run #6: crashed: BUG: soft lockup in smp_call_function run #7: crashed: BUG: soft lockup in smp_call_function run #8: crashed: BUG: soft lockup in smp_call_function run #9: crashed: BUG: soft lockup in smp_call_function # git bisect bad cc5f0eb2164f9aa11fe631f8d905192e0233e262 Bisecting: 33 revisions left to test after this (roughly 5 steps) [6a5e6b118092dfddc545d95911d66d6562f05281] Merge branch 'ieee802154-for-davem-2018-10-04' of git://git.kernel.org/pub/scm/linux/kernel/git/sschmidt/wpan-next testing commit 6a5e6b118092dfddc545d95911d66d6562f05281 with gcc (GCC) 8.1.0 kernel signature: 2a66c6804ce9006ed071517199b9a42b3deadbb2fca7ecf7a5a6a0ac89d49656 all runs: OK # git bisect good 6a5e6b118092dfddc545d95911d66d6562f05281 Bisecting: 15 revisions left to test after this (roughly 4 steps) [9e50727f0e710e25e9fd740c9f43f51b37757773] Merge tag 'mlx5-updates-2018-10-03' of git://git.kernel.org/pub/scm/linux/kernel/git/saeed/linux testing commit 9e50727f0e710e25e9fd740c9f43f51b37757773 with gcc (GCC) 8.1.0 kernel signature: 427f380ae5e8b6d054f410f0f0d06da8118fc5f3f595901ee8e3ec04109216df all runs: OK # git bisect good 9e50727f0e710e25e9fd740c9f43f51b37757773 Bisecting: 7 revisions left to test after this (roughly 3 steps) [2dc0865e9ac7150e2d3b29afdc32d04b99f37902] bnxt_en: Add a driver specific gre_ver_check devlink parameter. testing commit 2dc0865e9ac7150e2d3b29afdc32d04b99f37902 with gcc (GCC) 8.1.0 kernel signature: cd51862db13cadd6954231b9b8a61962ff50bcc85e07e6c7b8934dedbbeeb69b all runs: OK # git bisect good 2dc0865e9ac7150e2d3b29afdc32d04b99f37902 Bisecting: 3 revisions left to test after this (roughly 2 steps) [5a781ccbd19e4664babcbe4b4ead7aa2b9283d22] tc: Add support for configuring the taprio scheduler testing commit 5a781ccbd19e4664babcbe4b4ead7aa2b9283d22 with gcc (GCC) 8.1.0 kernel signature: 0f5dccb6e1b27f6e1d48798c6f6ee997c42a9131388a55f03f430c58ad008398 run #0: crashed: INFO: rcu detected stall in sys_clock_settime run #1: crashed: INFO: rcu detected stall in sys_clock_settime run #2: crashed: BUG: soft lockup in smp_call_function run #3: crashed: BUG: soft lockup in smp_call_function run #4: crashed: BUG: soft lockup in smp_call_function run #5: crashed: BUG: soft lockup in smp_call_function run #6: crashed: BUG: soft lockup in smp_call_function run #7: crashed: BUG: soft lockup in smp_call_function run #8: crashed: BUG: soft lockup in smp_call_function run #9: crashed: INFO: rcu detected stall in corrupted # git bisect bad 5a781ccbd19e4664babcbe4b4ead7aa2b9283d22 Bisecting: 1 revision left to test after this (roughly 1 step) [53e233ea2fa9fa7e2405e95070981f327d90e519] devlink: Add Documentation/networking/devlink-params-bnxt.txt testing commit 53e233ea2fa9fa7e2405e95070981f327d90e519 with gcc (GCC) 8.1.0 kernel signature: fb475db2c8da475e5f84bf080deaafcae32bb0d83484a8a71114bcfcf23cc165 all runs: OK # git bisect good 53e233ea2fa9fa7e2405e95070981f327d90e519 Bisecting: 0 revisions left to test after this (roughly 0 steps) [34f8c58f47797efa25ba212001514ef31e153134] Merge branch 'bnxt_en-devlink-param-updates' testing commit 34f8c58f47797efa25ba212001514ef31e153134 with gcc (GCC) 8.1.0 kernel signature: fd14002308b840a05c3b79eefeca662a3709c103cdbc3c72f6756f78f9276afe all runs: OK # git bisect good 34f8c58f47797efa25ba212001514ef31e153134 5a781ccbd19e4664babcbe4b4ead7aa2b9283d22 is the first bad commit commit 5a781ccbd19e4664babcbe4b4ead7aa2b9283d22 Author: Vinicius Costa Gomes Date: Fri Sep 28 17:59:43 2018 -0700 tc: Add support for configuring the taprio scheduler This traffic scheduler allows traffic classes states (transmission allowed/not allowed, in the simplest case) to be scheduled, according to a pre-generated time sequence. This is the basis of the IEEE 802.1Qbv specification. Example configuration: tc qdisc replace dev enp3s0 parent root handle 100 taprio \ num_tc 3 \ map 2 2 1 0 2 2 2 2 2 2 2 2 2 2 2 2 \ queues 1@0 1@1 2@2 \ base-time 1528743495910289987 \ sched-entry S 01 300000 \ sched-entry S 02 300000 \ sched-entry S 04 300000 \ clockid CLOCK_TAI The configuration format is similar to mqprio. The main difference is the presence of a schedule, built by multiple "sched-entry" definitions, each entry has the following format: sched-entry The only supported is "S", which means "SetGateStates", following the IEEE 802.1Qbv-2015 definition (Table 8-6). is a bitmask where each bit is a associated with a traffic class, so bit 0 (the least significant bit) being "on" means that traffic class 0 is "active" for that schedule entry. is a time duration in nanoseconds that specifies for how long that state defined by and should be held before moving to the next entry. This schedule is circular, that is, after the last entry is executed it starts from the first one, indefinitely. The other parameters can be defined as follows: - base-time: specifies the instant when the schedule starts, if 'base-time' is a time in the past, the schedule will start at base-time + (N * cycle-time) where N is the smallest integer so the resulting time is greater than "now", and "cycle-time" is the sum of all the intervals of the entries in the schedule; - clockid: specifies the reference clock to be used; The parameters should be similar to what the IEEE 802.1Q family of specification defines. Signed-off-by: Vinicius Costa Gomes Signed-off-by: David S. Miller include/uapi/linux/pkt_sched.h | 46 ++ net/sched/Kconfig | 11 + net/sched/Makefile | 1 + net/sched/sch_taprio.c | 962 +++++++++++++++++++++++++++++++++++++++++ 4 files changed, 1020 insertions(+) create mode 100644 net/sched/sch_taprio.c culprit signature: 0f5dccb6e1b27f6e1d48798c6f6ee997c42a9131388a55f03f430c58ad008398 parent signature: fd14002308b840a05c3b79eefeca662a3709c103cdbc3c72f6756f78f9276afe revisions tested: 25, total time: 5h37m36.800469048s (build: 2h29m48.588535033s, test: 3h4m0.950673081s) first bad commit: 5a781ccbd19e4664babcbe4b4ead7aa2b9283d22 tc: Add support for configuring the taprio scheduler cc: ["davem@davemloft.net" "jhs@mojatatu.com" "jiri@resnulli.us" "linux-kernel@vger.kernel.org" "netdev@vger.kernel.org" "vinicius.gomes@intel.com" "xiyou.wangcong@gmail.com"] crash: INFO: rcu detected stall in corrupted IPv6: ADDRCONF(NETDEV_UP): batadv_slave_0: link is not ready batman_adv: batadv0: Interface activated: batadv_slave_0 IPv6: ADDRCONF(NETDEV_CHANGE): batadv_slave_0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): veth0_to_batadv: link becomes ready rcu: INFO: rcu_preempt self-detected stall on CPU rcu: INFO: rcu_sched detected stalls on CPUs/tasks: rcu: 1-...!: (1 ticks this GP) idle=02a/1/0x4000000000000002 softirq=11452/11452 fqs=0 rcu: 1-...!: (1223 ticks this GP) idle=02a/1/0x4000000000000002 softirq=9940/11452 fqs=0 rcu: rcu: (t=15765 jiffies g=4837 q=4598) (detected by 0, t=15765 jiffies, g=-1031, q=10) rcu: rcu_preempt kthread starved for 15765 jiffies! g4837 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=1 Sending NMI from CPU 0 to CPUs 1: rcu: RCU grace-period kthread stack dump: NMI backtrace for cpu 1 CPU: 1 PID: 7724 Comm: syz-executor.2 Not tainted 4.19.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:io_serial_in+0x60/0x90 drivers/tty/serial/8250/8250_port.c:450 Code: 0f b6 8b e1 00 00 00 48 8d 7b 38 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 d3 e6 80 3c 02 00 75 1d 03 73 38 89 f2 ec <48> 83 c4 08 0f b6 c0 5b 5d c3 89 75 f4 e8 be 7c 1c fe 8b 75 f4 eb RSP: 0018:ffff8800aeb07950 EFLAGS: 00000006 RAX: dffffc0000000005 RBX: ffffffff8aba5cc0 RCX: 0000000000000000 RDX: 00000000000003f9 RSI: 00000000000003f9 RDI: ffffffff8aba5cf8 RBP: ffff8800aeb07960 R08: fffffbfff1574b99 R09: fffffbfff1574b98 R10: fffffbfff1574b98 R11: ffffffff8aba5cc3 R12: ffffffff8aba5ee0 R13: dffffc0000000000 R14: ffffffff8aba5cc0 R15: ffffffff8aba5d08 FS: 00007f36298c9700(0000) GS:ffff8800aeb00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fd112af2bf8 CR3: 000000009058c000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: serial_port_in include/linux/serial_core.h:268 [inline] serial8250_console_write+0x248/0x880 drivers/tty/serial/8250/8250_port.c:3252 univ8250_console_write+0x4e/0x70 drivers/tty/serial/8250/8250_core.c:590 call_console_drivers kernel/printk/printk.c:1724 [inline] console_unlock+0x845/0xdf0 kernel/printk/printk.c:2405 vprintk_emit+0x334/0x4f0 kernel/printk/printk.c:1922 vprintk_default+0x1a/0x20 kernel/printk/printk.c:1963 vprintk_func+0x42/0x125 kernel/printk/printk_safe.c:398 printk+0x9a/0xc0 kernel/printk/printk.c:1996 rcu_check_gp_kthread_starvation+0x25d/0x2c0 kernel/rcu/tree.c:1317 print_cpu_stall kernel/rcu/tree.c:1476 [inline] check_cpu_stall kernel/rcu/tree.c:1550 [inline] __rcu_pending kernel/rcu/tree.c:3276 [inline] rcu_pending kernel/rcu/tree.c:3319 [inline] rcu_check_callbacks.cold.61+0x5b5/0xd3d kernel/rcu/tree.c:2665 update_process_times+0x2a/0x60 kernel/time/timer.c:1636 tick_sched_handle.isra.5+0x6b/0x130 kernel/time/tick-sched.c:164 tick_sched_timer+0x3c/0xf0 kernel/time/tick-sched.c:1274 __run_hrtimer kernel/time/hrtimer.c:1398 [inline] __hrtimer_run_queues+0x2fa/0xaa0 kernel/time/hrtimer.c:1460 hrtimer_interrupt+0x2df/0x760 kernel/time/hrtimer.c:1518 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1029 [inline] smp_apic_timer_interrupt+0x114/0x530 arch/x86/kernel/apic/apic.c:1054 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:864 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:788 [inline] RIP: 0010:on_each_cpu+0x13c/0x180 kernel/smp.c:607 Code: 48 9c 51 88 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 75 43 48 83 3d a3 08 fb 06 00 74 19 48 89 df 57 9d <0f> 1f 44 00 00 eb a6 0f 0b 0f 0b 0f 0b e8 8d c0 a9 ff eb ae 0f 0b RSP: 0018:ffff88008fc17d30 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13 RAX: dffffc0000000000 RBX: 0000000000000282 RCX: 0000000000000000 RDX: 1ffffffff10a3389 RSI: 0000000000000004 RDI: 0000000000000282 RBP: ffff88008fc17d50 R08: ffffed0015d64b79 R09: ffffed0015d64b78 R10: ffffed0015d64b78 R11: ffff8800aeb25bc3 R12: ffffffff8152ca80 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000282 clock_was_set+0x17/0x20 kernel/time/hrtimer.c:861 do_settimeofday64+0x24a/0x320 kernel/time/timekeeping.c:1270 do_sys_settimeofday64+0x154/0x1d0 kernel/time/time.c:196 posix_clock_realtime_set+0xe/0x10 kernel/time/posix-timers.c:199 __do_sys_clock_settime kernel/time/posix-timers.c:1053 [inline] __se_sys_clock_settime+0xcf/0x140 kernel/time/posix-timers.c:1041 __x64_sys_clock_settime+0x4f/0x70 kernel/time/posix-timers.c:1041 do_syscall_64+0xd0/0x4d0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45cba9 Code: 8d b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 5b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f36298c8c78 EFLAGS: 00000246 ORIG_RAX: 00000000000000e3 RAX: ffffffffffffffda RBX: 00000000004dbd60 RCX: 000000000045cba9 RDX: 0000000000000000 RSI: 0000000020000400 RDI: 0000000000000000 RBP: 000000000078bfa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 000000000000007b R14: 00000000004c352c R15: 00007f36298c96d4 rcu: rcu_sched kthread starved for 15765 jiffies! g-1031 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=0 rcu_preempt I rcu: RCU grace-period kthread stack dump: rcu_sched I 29608 10 2 0x80000000 30080 11 2 0x80000000 Call Trace: Call Trace: context_switch kernel/sched/core.c:2825 [inline] __schedule+0x80c/0x1f20 kernel/sched/core.c:3473 context_switch kernel/sched/core.c:2825 [inline] __schedule+0x80c/0x1f20 kernel/sched/core.c:3473 schedule+0x7f/0x1b0 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3517 schedule_timeout+0x398/0xcc0 kernel/time/timer.c:1804 schedule_timeout+0x398/0xcc0 kernel/time/timer.c:1804 rcu_gp_kthread+0xd30/0x2130 kernel/rcu/tree.c:2194 rcu_gp_kthread+0xd30/0x2130 kernel/rcu/tree.c:2194 kthread+0x324/0x3e0 kernel/kthread.c:246 kthread+0x324/0x3e0 kernel/kthread.c:246 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:413 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:413 rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { NMI backtrace for cpu 1 1-... CPU: 1 PID: 7724 Comm: syz-executor.2 Not tainted 4.19.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x15a/0x20d lib/dump_stack.c:113 nmi_cpu_backtrace.cold.0+0x3c/0x78 lib/nmi_backtrace.c:101 } 15765 jiffies s: 297 root: 0x2/. nmi_trigger_cpumask_backtrace+0xf5/0x119 lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_single_cpu_backtrace include/linux/nmi.h:162 [inline] rcu_dump_cpu_stacks+0x175/0x1c2 kernel/rcu/tree.c:1340 rcu: blocking rcu_node structures: print_cpu_stall kernel/rcu/tree.c:1478 [inline] check_cpu_stall kernel/rcu/tree.c:1550 [inline] __rcu_pending kernel/rcu/tree.c:3276 [inline] rcu_pending kernel/rcu/tree.c:3319 [inline] rcu_check_callbacks.cold.61+0x5bd/0xd3d kernel/rcu/tree.c:2665 Task dump for CPU 1: syz-executor.2 R update_process_times+0x2a/0x60 kernel/time/timer.c:1636 running task tick_sched_handle.isra.5+0x6b/0x130 kernel/time/tick-sched.c:164 tick_sched_timer+0x3c/0xf0 kernel/time/tick-sched.c:1274 __run_hrtimer kernel/time/hrtimer.c:1398 [inline] __hrtimer_run_queues+0x2fa/0xaa0 kernel/time/hrtimer.c:1460 29648 7724 6442 0x8000000c Call Trace: hrtimer_interrupt+0x2df/0x760 kernel/time/hrtimer.c:1518 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1029 [inline] smp_apic_timer_interrupt+0x114/0x530 arch/x86/kernel/apic/apic.c:1054 context_switch kernel/sched/core.c:2828 [inline] __schedule+0x814/0x1f20 kernel/sched/core.c:3473 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:864 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:788 [inline] RIP: 0010:on_each_cpu+0x13c/0x180 kernel/smp.c:607 Code: 48 9c 51 88 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 75 43 48 83 3d a3 08 fb 06 00 74 19 48 89 df 57 9d <0f> 1f 44 00 00 eb a6 0f 0b 0f 0b 0f 0b e8 8d c0 a9 ff eb ae 0f 0b RSP: 0018:ffff88008fc17d30 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13 RAX: dffffc0000000000 RBX: 0000000000000282 RCX: 0000000000000000 RDX: 1ffffffff10a3389 RSI: 0000000000000004 RDI: 0000000000000282 RBP: ffff88008fc17d50 R08: ffffed0015d64b79 R09: ffffed0015d64b78 R10: ffffed0015d64b78 R11: ffff8800aeb25bc3 R12: ffffffff8152ca80 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000282 clock_was_set+0x17/0x20 kernel/time/hrtimer.c:861 do_settimeofday64+0x24a/0x320 kernel/time/timekeeping.c:1270 do_sys_settimeofday64+0x154/0x1d0 kernel/time/time.c:196 posix_clock_realtime_set+0xe/0x10 kernel/time/posix-timers.c:199 __do_sys_clock_settime kernel/time/posix-timers.c:1053 [inline] __se_sys_clock_settime+0xcf/0x140 kernel/time/posix-timers.c:1041 __x64_sys_clock_settime+0x4f/0x70 kernel/time/posix-timers.c:1041 do_syscall_64+0xd0/0x4d0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45cba9 Code: 8d b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 5b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f36298c8c78 EFLAGS: 00000246 ORIG_RAX: 00000000000000e3 RAX: ffffffffffffffda RBX: 00000000004dbd60 RCX: 000000000045cba9 RDX: 0000000000000000 RSI: 0000000020000400 RDI: 0000000000000000 RBP: 000000000078bfa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 000000000000007b R14: 00000000004c352c R15: 00007f36298c96d4 WARNING: CPU: 1 PID: 18 at kernel/fork.c:408 free_task+0xb4/0xd0 kernel/fork.c:415