bisecting fixing commit since 53bd76690e27f37c9df221a651a52cea04214da9 building syzkaller on 6c236867ce33c0c16b102e02a08226d7eb9b2046 testing commit 53bd76690e27f37c9df221a651a52cea04214da9 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: b991b625e5db74bac3d94bf93cff7fcd6b978415abd093508686d46fadbc0cdc run #0: crashed: BUG: soft lockup in addrconf_dad_work run #1: crashed: BUG: soft lockup in addrconf_dad_work run #2: crashed: BUG: soft lockup in addrconf_dad_work run #3: crashed: BUG: soft lockup in addrconf_dad_work run #4: crashed: BUG: soft lockup in addrconf_dad_work run #5: crashed: BUG: soft lockup in mld_dad_timer_expire run #6: crashed: BUG: soft lockup in addrconf_dad_work run #7: crashed: BUG: soft lockup in addrconf_dad_work run #8: crashed: BUG: soft lockup in addrconf_dad_work run #9: crashed: BUG: soft lockup in addrconf_dad_work run #10: crashed: BUG: soft lockup in mld_ifc_timer_expire run #11: crashed: BUG: soft lockup in addrconf_dad_work run #12: crashed: BUG: soft lockup in addrconf_dad_work run #13: crashed: BUG: soft lockup in addrconf_dad_work run #14: crashed: BUG: soft lockup in mld_ifc_timer_expire run #15: crashed: BUG: soft lockup in addrconf_dad_work run #16: crashed: BUG: soft lockup in mld_dad_timer_expire run #17: crashed: BUG: soft lockup in addrconf_dad_work run #18: crashed: BUG: soft lockup in addrconf_dad_work run #19: crashed: BUG: soft lockup in addrconf_dad_work testing current HEAD c2276d585654e8d573366c29c565043ec36adf63 testing commit c2276d585654e8d573366c29c565043ec36adf63 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 182d81b73761c682c630d9e7e491a772c1cfcdf0c34c832176dcc5feb988706c all runs: OK # git bisect start c2276d585654e8d573366c29c565043ec36adf63 53bd76690e27f37c9df221a651a52cea04214da9 Bisecting: 280 revisions left to test after this (roughly 8 steps) [b51cb36e1f849020ec34f2b7f9d06eb57ba058eb] crypto: qat - handle both source of interrupt in VF ISR testing commit b51cb36e1f849020ec34f2b7f9d06eb57ba058eb compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 131933e4280d3fd4787df59b3f1c4659d8329f82df3dc7cea5231b065bbc3001 run #0: crashed: BUG: soft lockup in addrconf_dad_work run #1: crashed: BUG: soft lockup in addrconf_dad_work run #2: crashed: BUG: soft lockup in addrconf_dad_work run #3: crashed: BUG: soft lockup in mld_dad_timer_expire run #4: crashed: BUG: soft lockup in addrconf_dad_work run #5: crashed: BUG: soft lockup in mld_ifc_timer_expire run #6: crashed: BUG: soft lockup in addrconf_dad_work run #7: crashed: BUG: soft lockup in addrconf_dad_work run #8: crashed: BUG: soft lockup in mld_ifc_timer_expire run #9: crashed: BUG: soft lockup in addrconf_dad_work # git bisect good b51cb36e1f849020ec34f2b7f9d06eb57ba058eb Bisecting: 140 revisions left to test after this (roughly 7 steps) [5fa42b748728f418da5f9574e2d0383c466d842a] bpf/tests: Fix copy-and-paste error in double word test testing commit 5fa42b748728f418da5f9574e2d0383c466d842a compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 3922324ec8740f5e7825530d5acea6161e89bb6fe4f5b653e8d494774c7202f1 run #0: crashed: BUG: soft lockup in addrconf_dad_work run #1: crashed: BUG: soft lockup in addrconf_dad_work run #2: crashed: BUG: soft lockup in addrconf_dad_work run #3: crashed: BUG: soft lockup in addrconf_dad_work run #4: crashed: BUG: soft lockup in addrconf_dad_work run #5: crashed: BUG: soft lockup in mld_dad_timer_expire run #6: crashed: BUG: soft lockup in addrconf_dad_work run #7: crashed: BUG: soft lockup in addrconf_dad_work run #8: crashed: BUG: soft lockup in mld_ifc_timer_expire run #9: crashed: BUG: soft lockup in addrconf_dad_work # git bisect good 5fa42b748728f418da5f9574e2d0383c466d842a Bisecting: 70 revisions left to test after this (roughly 6 steps) [9abcfed25029c1a99029914823389ea8f213d3df] net-caif: avoid user-triggerable WARN_ON(1) testing commit 9abcfed25029c1a99029914823389ea8f213d3df compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 5fb10420e832f1a22f8d3d0aba7c47583efee00e70ab2a774a11a23fffc9f36c run #0: crashed: BUG: soft lockup in addrconf_dad_work run #1: crashed: BUG: soft lockup in mld_dad_timer_expire run #2: crashed: BUG: soft lockup in addrconf_dad_work run #3: crashed: BUG: soft lockup in mld_dad_timer_expire run #4: crashed: BUG: soft lockup in addrconf_dad_work run #5: crashed: BUG: soft lockup in addrconf_dad_work run #6: crashed: BUG: soft lockup in addrconf_dad_work run #7: crashed: BUG: soft lockup in addrconf_dad_work run #8: crashed: BUG: soft lockup in addrconf_rs_timer run #9: crashed: BUG: soft lockup in addrconf_dad_work # git bisect good 9abcfed25029c1a99029914823389ea8f213d3df Bisecting: 35 revisions left to test after this (roughly 5 steps) [044e7097e849366dfc71cccfc5d8c8a97cb3f010] net: renesas: sh_eth: Fix freeing wrong tx descriptor testing commit 044e7097e849366dfc71cccfc5d8c8a97cb3f010 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 7e4dffc9fe495a3e94f9ddceefe624cb345575d9420f6a6a4b9abb23c411ed2b all runs: OK # git bisect bad 044e7097e849366dfc71cccfc5d8c8a97cb3f010 Bisecting: 17 revisions left to test after this (roughly 4 steps) [05e4fdd51a934d4bf51b368e5c00dd35f744637e] dt-bindings: mtd: gpmc: Fix the ECC bytes vs. OOB bytes equation testing commit 05e4fdd51a934d4bf51b368e5c00dd35f744637e compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: b27e430d2c46b974991ba65ab4f3448fa87212f609ed3ca7d56653b51e085df2 run #0: crashed: BUG: soft lockup in mld_dad_timer_expire run #1: crashed: BUG: soft lockup in mld_dad_timer_expire run #2: crashed: BUG: soft lockup in addrconf_dad_work run #3: crashed: BUG: soft lockup in addrconf_dad_work run #4: crashed: BUG: soft lockup in mld_dad_timer_expire run #5: crashed: BUG: soft lockup in mld_dad_timer_expire run #6: crashed: BUG: soft lockup in addrconf_dad_work run #7: crashed: BUG: soft lockup in addrconf_dad_work run #8: crashed: BUG: soft lockup in addrconf_dad_work run #9: crashed: BUG: soft lockup in mld_ifc_timer_expire # git bisect good 05e4fdd51a934d4bf51b368e5c00dd35f744637e Bisecting: 8 revisions left to test after this (roughly 3 steps) [b6e5cd323d1d1537f450ab0d3e06811a868267c2] KVM: arm64: Handle PSCI resets before userspace touches vCPU state testing commit b6e5cd323d1d1537f450ab0d3e06811a868267c2 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 91add4dd8f8e7941a1ddac94ea787ca3a259f33ee30c2e0a9175b9134a369f5c run #0: crashed: BUG: soft lockup in addrconf_dad_work run #1: crashed: BUG: soft lockup in mld_dad_timer_expire run #2: crashed: BUG: soft lockup in addrconf_dad_work run #3: crashed: BUG: soft lockup in addrconf_dad_work run #4: crashed: BUG: soft lockup in mld_ifc_timer_expire run #5: crashed: BUG: soft lockup in addrconf_dad_work run #6: crashed: BUG: soft lockup in mld_ifc_timer_expire run #7: crashed: BUG: soft lockup in mld_ifc_timer_expire run #8: crashed: BUG: soft lockup in addrconf_dad_work run #9: crashed: BUG: soft lockup in mld_dad_timer_expire # git bisect good b6e5cd323d1d1537f450ab0d3e06811a868267c2 Bisecting: 4 revisions left to test after this (roughly 2 steps) [e24ffdb604179a057e9be5c9a8ed68b90a28eee5] net: dsa: b53: Fix calculating number of switch ports testing commit e24ffdb604179a057e9be5c9a8ed68b90a28eee5 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 91add4dd8f8e7941a1ddac94ea787ca3a259f33ee30c2e0a9175b9134a369f5c run #0: crashed: BUG: soft lockup in addrconf_dad_work run #1: crashed: BUG: soft lockup in addrconf_dad_work run #2: crashed: BUG: soft lockup in addrconf_dad_work run #3: crashed: BUG: soft lockup in mld_dad_timer_expire run #4: crashed: BUG: soft lockup in addrconf_dad_work run #5: crashed: BUG: soft lockup in addrconf_dad_work run #6: crashed: BUG: soft lockup in mld_dad_timer_expire run #7: crashed: BUG: soft lockup in addrconf_dad_work run #8: crashed: BUG: soft lockup in mld_ifc_timer_expire run #9: crashed: BUG: soft lockup in addrconf_dad_work # git bisect good e24ffdb604179a057e9be5c9a8ed68b90a28eee5 Bisecting: 2 revisions left to test after this (roughly 1 step) [7c113506163a1ec6157927428eddd80038d2916e] fq_codel: reject silly quantum parameters testing commit 7c113506163a1ec6157927428eddd80038d2916e compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: e03e13855118ecc0716df7699489d15ad1082b78c45773f4c71789768f6afb04 all runs: OK # git bisect bad 7c113506163a1ec6157927428eddd80038d2916e Bisecting: 0 revisions left to test after this (roughly 0 steps) [d6efada330af09253b0f81a0d836cee02192bd4f] netfilter: socket: icmp6: fix use-after-scope testing commit d6efada330af09253b0f81a0d836cee02192bd4f compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 0b2846274ef5dfbca6199bad35e9f98c7cdab25e0ae482fa9cd5d2802a0b68b9 run #0: crashed: BUG: soft lockup in addrconf_dad_work run #1: crashed: BUG: soft lockup in addrconf_dad_work run #2: crashed: BUG: soft lockup in addrconf_dad_work run #3: crashed: BUG: soft lockup in addrconf_dad_work run #4: crashed: BUG: soft lockup in addrconf_dad_work run #5: crashed: BUG: soft lockup in addrconf_dad_work run #6: crashed: BUG: soft lockup in addrconf_dad_work run #7: crashed: BUG: soft lockup in addrconf_dad_work run #8: crashed: BUG: soft lockup in mld_ifc_timer_expire run #9: crashed: BUG: soft lockup in mld_dad_timer_expire # git bisect good d6efada330af09253b0f81a0d836cee02192bd4f 7c113506163a1ec6157927428eddd80038d2916e is the first bad commit commit 7c113506163a1ec6157927428eddd80038d2916e Author: Eric Dumazet Date: Fri Sep 3 15:03:43 2021 -0700 fq_codel: reject silly quantum parameters [ Upstream commit c7c5e6ff533fe1f9afef7d2fa46678987a1335a7 ] syzbot found that forcing a big quantum attribute would crash hosts fast, essentially using this: tc qd replace dev eth0 root fq_codel quantum 4294967295 This is because fq_codel_dequeue() would have to loop ~2^31 times in : if (flow->deficit <= 0) { flow->deficit += q->quantum; list_move_tail(&flow->flowchain, &q->old_flows); goto begin; } SFQ max quantum is 2^19 (half a megabyte) Lets adopt a max quantum of one megabyte for FQ_CODEL. Fixes: 4b549a2ef4be ("fq_codel: Fair Queue Codel AQM") Signed-off-by: Eric Dumazet Reported-by: syzbot Signed-off-by: David S. Miller Signed-off-by: Sasha Levin include/uapi/linux/pkt_sched.h | 2 ++ net/sched/sch_fq_codel.c | 12 ++++++++++-- 2 files changed, 12 insertions(+), 2 deletions(-) culprit signature: e03e13855118ecc0716df7699489d15ad1082b78c45773f4c71789768f6afb04 parent signature: 0b2846274ef5dfbca6199bad35e9f98c7cdab25e0ae482fa9cd5d2802a0b68b9 revisions tested: 11, total time: 2h52m21.901885803s (build: 1h48m22.924274283s, test: 1h2m47.912404406s) first good commit: 7c113506163a1ec6157927428eddd80038d2916e fq_codel: reject silly quantum parameters recipients (to): ["davem@davemloft.net" "edumazet@google.com" "sashal@kernel.org"] recipients (cc): []