bisecting fixing commit since 63623fd44972d1ed2bfb6e0fb631dfcf547fd1e7 building syzkaller on c88c7b75a4e022b758f4b0f1bf3db8ebb2fb25e6 testing commit 63623fd44972d1ed2bfb6e0fb631dfcf547fd1e7 with gcc (GCC) 8.1.0 kernel signature: 189649acd9cabb6b22f122dbfc1f569a80ca7944d9913d864f898ed1d9fdb3dd run #0: crashed: possible deadlock in seq_read run #1: crashed: possible deadlock in lock_trace run #2: crashed: possible deadlock in seq_read run #3: crashed: possible deadlock in lock_trace run #4: crashed: possible deadlock in lock_trace run #5: crashed: possible deadlock in lock_trace run #6: crashed: possible deadlock in lock_trace run #7: crashed: possible deadlock in lock_trace run #8: crashed: possible deadlock in lock_trace run #9: crashed: possible deadlock in lock_trace testing current HEAD 8632e9b5645bbc2331d21d892b0d6961c1a08429 testing commit 8632e9b5645bbc2331d21d892b0d6961c1a08429 with gcc (GCC) 8.1.0 kernel signature: 0cf34db0a56192fc3b3216f9f2fc50297a84ffacc02be54bb708482e82a8cf03 all runs: OK # git bisect start 8632e9b5645bbc2331d21d892b0d6961c1a08429 63623fd44972d1ed2bfb6e0fb631dfcf547fd1e7 Bisecting: 7076 revisions left to test after this (roughly 13 steps) [222100eed264ba9d640af9977bffb6fcb6f11ea3] mm/vma: make is_vma_temporary_stack() available for general use testing commit 222100eed264ba9d640af9977bffb6fcb6f11ea3 with gcc (GCC) 8.1.0 kernel signature: 0b82110d744a120f21ce98afca3c379578ec5966267c3b213ceede1ba3a0df92 run #0: crashed: possible deadlock in seq_read run #1: crashed: possible deadlock in lock_trace run #2: crashed: possible deadlock in seq_read run #3: crashed: possible deadlock in lock_trace run #4: crashed: possible deadlock in lock_trace run #5: crashed: possible deadlock in lock_trace run #6: crashed: possible deadlock in lock_trace run #7: crashed: possible deadlock in lock_trace run #8: crashed: possible deadlock in lock_trace run #9: crashed: possible deadlock in lock_trace # git bisect good 222100eed264ba9d640af9977bffb6fcb6f11ea3 Bisecting: 3449 revisions left to test after this (roughly 12 steps) [79f51b7b9c4719303f758ae8406c4e5997ed6aa3] Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi testing commit 79f51b7b9c4719303f758ae8406c4e5997ed6aa3 with gcc (GCC) 8.1.0 kernel signature: 9adfff10fe51c24f140c88bdd6c4869a20c039c5f062fd8a186e3d7defac432c all runs: OK # git bisect bad 79f51b7b9c4719303f758ae8406c4e5997ed6aa3 Bisecting: 1802 revisions left to test after this (roughly 11 steps) [397a97946798890b9bdaa6122fcfad7147690670] Merge tag 'linux-kselftest-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest testing commit 397a97946798890b9bdaa6122fcfad7147690670 with gcc (GCC) 8.1.0 kernel signature: 4315080b1cd223c0549b3d9dd38dc3af01e17349952dafc1b5663a95fe615bee run #0: crashed: possible deadlock in seq_read run #1: crashed: possible deadlock in lock_trace run #2: crashed: possible deadlock in lock_trace run #3: crashed: possible deadlock in lock_trace run #4: crashed: possible deadlock in seq_read run #5: crashed: possible deadlock in lock_trace run #6: crashed: possible deadlock in lock_trace run #7: crashed: possible deadlock in lock_trace run #8: crashed: possible deadlock in lock_trace run #9: crashed: possible deadlock in lock_trace # git bisect good 397a97946798890b9bdaa6122fcfad7147690670 Bisecting: 913 revisions left to test after this (roughly 10 steps) [bc3b3f4bfbded031a11c4284106adddbfacd05bb] Merge tag 'pinctrl-v5.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl testing commit bc3b3f4bfbded031a11c4284106adddbfacd05bb with gcc (GCC) 8.1.0 kernel signature: 562891ff7b8346d50d2e1dcdb40189550241c1e50e36fee8530a31e1fd8f9cf9 run #0: OK 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: boot failed: can't ssh into the instance # git bisect bad bc3b3f4bfbded031a11c4284106adddbfacd05bb Bisecting: 478 revisions left to test after this (roughly 9 steps) [7be97138e7276c71cc9ad1752dcb502d28f4400d] Merge tag 'xfs-5.7-merge-8' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux testing commit 7be97138e7276c71cc9ad1752dcb502d28f4400d with gcc (GCC) 8.1.0 kernel signature: 5b3738fe74c03e6b1fd9f3a9f5af10395627d1f612349dddc41983a85b11391f all runs: OK # git bisect bad 7be97138e7276c71cc9ad1752dcb502d28f4400d Bisecting: 212 revisions left to test after this (roughly 8 steps) [919dce24701f7b34681a6a1d3ef95c9f6c4fb1cc] Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma testing commit 919dce24701f7b34681a6a1d3ef95c9f6c4fb1cc with gcc (GCC) 8.1.0 kernel signature: 579513b7e2144f0a1c0369e68a0faabc6a271491e46d1c3146a93fb681c5d4b0 run #0: crashed: possible deadlock in seq_read run #1: crashed: possible deadlock in lock_trace run #2: crashed: possible deadlock in seq_read run #3: crashed: possible deadlock in lock_trace run #4: crashed: possible deadlock in lock_trace run #5: crashed: possible deadlock in lock_trace run #6: crashed: possible deadlock in lock_trace run #7: crashed: possible deadlock in lock_trace run #8: crashed: possible deadlock in lock_trace run #9: boot failed: can't ssh into the instance # git bisect good 919dce24701f7b34681a6a1d3ef95c9f6c4fb1cc Bisecting: 106 revisions left to test after this (roughly 7 steps) [d59f44d3e723c4f7143d910dfa333f2bdb587bbc] xfs: directory bestfree check should release buffers testing commit d59f44d3e723c4f7143d910dfa333f2bdb587bbc with gcc (GCC) 8.1.0 kernel signature: 0e47822daa1484974165ba68cef20c42cd9909b916dd0a49cf42315b09b8fb10 run #0: crashed: possible deadlock in seq_read run #1: crashed: possible deadlock in seq_read run #2: crashed: possible deadlock in seq_read run #3: crashed: possible deadlock in lock_trace run #4: crashed: possible deadlock in lock_trace run #5: crashed: possible deadlock in seq_read run #6: crashed: possible deadlock in lock_trace run #7: crashed: possible deadlock in seq_read run #8: crashed: possible deadlock in lock_trace run #9: crashed: possible deadlock in lock_trace # git bisect good d59f44d3e723c4f7143d910dfa333f2bdb587bbc Bisecting: 53 revisions left to test after this (roughly 6 steps) [7ef482fa65513b18eed05a5c5f00413aad137810] helper for mount rootwards traversal testing commit 7ef482fa65513b18eed05a5c5f00413aad137810 with gcc (GCC) 8.1.0 kernel signature: 86f008ad6620f24dac507ad0ba9c7f3e351b1a7406ade6b0177666c4e827ae9f run #0: crashed: possible deadlock in seq_read run #1: crashed: possible deadlock in seq_read run #2: crashed: possible deadlock in seq_read run #3: crashed: possible deadlock in seq_read run #4: crashed: possible deadlock in lock_trace run #5: crashed: possible deadlock in lock_trace run #6: crashed: possible deadlock in lock_trace run #7: crashed: possible deadlock in lock_trace run #8: crashed: possible deadlock in lock_trace run #9: crashed: possible deadlock in lock_trace # git bisect good 7ef482fa65513b18eed05a5c5f00413aad137810 Bisecting: 26 revisions left to test after this (roughly 5 steps) [4b871ce26ab2c758ea90b8dd659e4267aae9e943] Merged 'Infrastructure to allow fixing exec deadlocks' from Bernd Edlinger testing commit 4b871ce26ab2c758ea90b8dd659e4267aae9e943 with gcc (GCC) 8.1.0 kernel signature: 352e5bbe59ff6fbccf10387eb30e04d1234bd9f9ac21c9dbbe676973298fb053 all runs: OK # git bisect bad 4b871ce26ab2c758ea90b8dd659e4267aae9e943 Bisecting: 13 revisions left to test after this (roughly 4 steps) [2ca7be7d55ad84fb0f7c2a23fb700a28fd76b19a] exec: Only compute current once in flush_old_exec testing commit 2ca7be7d55ad84fb0f7c2a23fb700a28fd76b19a with gcc (GCC) 8.1.0 kernel signature: f14933919dd7031d1b1cecbca10e6b773464a5434bfed7f5a4c4b517addbfc62 run #0: crashed: possible deadlock in seq_read run #1: crashed: possible deadlock in seq_read run #2: crashed: possible deadlock in seq_read run #3: crashed: possible deadlock in lock_trace run #4: crashed: possible deadlock in lock_trace run #5: crashed: possible deadlock in seq_read run #6: crashed: possible deadlock in lock_trace run #7: crashed: possible deadlock in seq_read run #8: crashed: possible deadlock in lock_trace run #9: crashed: possible deadlock in lock_trace # git bisect good 2ca7be7d55ad84fb0f7c2a23fb700a28fd76b19a Bisecting: 6 revisions left to test after this (roughly 3 steps) [8d09db80ef404d8e2e143677e0716cfcd544e29b] mm: docs: Fix a comment in process_vm_rw_core testing commit 8d09db80ef404d8e2e143677e0716cfcd544e29b with gcc (GCC) 8.1.0 kernel signature: 58bd7fe12ded09ce52bdd2e9e0be7138e9fbe35d284c051a8b591b0067bd5a75 run #0: crashed: possible deadlock in seq_read run #1: crashed: possible deadlock in lock_trace run #2: crashed: possible deadlock in seq_read run #3: crashed: possible deadlock in lock_trace run #4: crashed: possible deadlock in seq_read run #5: crashed: possible deadlock in seq_read run #6: crashed: possible deadlock in lock_trace run #7: crashed: possible deadlock in lock_trace run #8: crashed: possible deadlock in seq_read run #9: crashed: possible deadlock in lock_trace # git bisect good 8d09db80ef404d8e2e143677e0716cfcd544e29b Bisecting: 3 revisions left to test after this (roughly 2 steps) [2db9dbf71bf98d02a0bf33e798e5bfd2a9944696] proc: Use new infrastructure to fix deadlocks in execve testing commit 2db9dbf71bf98d02a0bf33e798e5bfd2a9944696 with gcc (GCC) 8.1.0 kernel signature: 9cbf1b77b2650ee8d30b8fe4daed8d290fe3e7d5bc78e22ea27d0cb8a02e2328 run #0: OK 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: boot failed: can't ssh into the instance # git bisect bad 2db9dbf71bf98d02a0bf33e798e5bfd2a9944696 Bisecting: 0 revisions left to test after this (roughly 1 step) [454e3126cb842388e22df6b3ac3da44062c00765] kernel/kcmp.c: Use new infrastructure to fix deadlocks in execve testing commit 454e3126cb842388e22df6b3ac3da44062c00765 with gcc (GCC) 8.1.0 kernel signature: 4a0d8e77a2f60262725de2c9958860f823369fd1b065b4979b10c52970972464 run #0: crashed: possible deadlock in lock_trace run #1: crashed: possible deadlock in lock_trace run #2: crashed: possible deadlock in lock_trace run #3: crashed: possible deadlock in lock_trace run #4: crashed: possible deadlock in seq_read run #5: crashed: possible deadlock in lock_trace run #6: crashed: possible deadlock in lock_trace run #7: crashed: possible deadlock in seq_read run #8: crashed: possible deadlock in lock_trace run #9: crashed: possible deadlock in lock_trace # git bisect good 454e3126cb842388e22df6b3ac3da44062c00765 2db9dbf71bf98d02a0bf33e798e5bfd2a9944696 is the first bad commit commit 2db9dbf71bf98d02a0bf33e798e5bfd2a9944696 Author: Bernd Edlinger Date: Fri Mar 20 21:27:24 2020 +0100 proc: Use new infrastructure to fix deadlocks in execve This changes lock_trace to use the new exec_update_mutex instead of cred_guard_mutex. This fixes possible deadlocks when the trace is accessing /proc/$pid/stack for instance. This should be safe, as the credentials are only used for reading, and task->mm is updated on execve under the new exec_update_mutex. Signed-off-by: Bernd Edlinger Signed-off-by: Eric W. Biederman fs/proc/base.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) culprit signature: 9cbf1b77b2650ee8d30b8fe4daed8d290fe3e7d5bc78e22ea27d0cb8a02e2328 parent signature: 4a0d8e77a2f60262725de2c9958860f823369fd1b065b4979b10c52970972464 revisions tested: 15, total time: 3h22m59.648059761s (build: 1h33m57.375595137s, test: 1h47m55.233621993s) first good commit: 2db9dbf71bf98d02a0bf33e798e5bfd2a9944696 proc: Use new infrastructure to fix deadlocks in execve cc: ["adobriyan@gmail.com" "akpm@linux-foundation.org" "avagin@gmail.com" "bernd.edlinger@hotmail.de" "ebiederm@xmission.com" "linux-fsdevel@vger.kernel.org" "linux-kernel@vger.kernel.org"]