bisecting cause commit starting from 8f8972a3127ff46df62ae30057d29606968ec4aa building syzkaller on 0342f8c7bc656ea8ee3c45e49edeb4ee9cc12cce testing commit 8f8972a3127ff46df62ae30057d29606968ec4aa with gcc (GCC) 8.1.0 kernel signature: 79997370cc3830520d4160fdfe29fb613cdbda12421fa6b4be096d0aa9945379 run #0: crashed: INFO: task hung in hashlimit_mt_check_common run #1: crashed: INFO: task hung in hashlimit_mt_check_common run #2: crashed: INFO: task hung in hashlimit_mt_check_common run #3: crashed: INFO: task hung in hashlimit_mt_check_common run #4: crashed: INFO: task hung in htable_put run #5: crashed: INFO: task hung in hashlimit_mt_check_common run #6: crashed: INFO: task hung in htable_put run #7: crashed: INFO: task hung in htable_put run #8: crashed: INFO: task hung in htable_put run #9: crashed: INFO: task hung in hashlimit_mt_check_common testing release v5.4 testing commit 219d54332a09e8d8741c1e1982f5eae56099de85 with gcc (GCC) 8.1.0 kernel signature: b97d909f72c12e5178268539a0d6fa8e68125fdf6b47e6efb01b405e179e0ca7 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" "/tmp/syz-executor557615102" "root@10.128.10.47:./syz-executor557615102"]: exit status 1 Connection timed out during banner exchange lost connection run #1: crashed: INFO: task hung in htable_put run #2: crashed: INFO: task hung in htable_put run #3: crashed: INFO: task hung in htable_put run #4: crashed: INFO: task hung in htable_put run #5: crashed: INFO: task hung in htable_put run #6: crashed: INFO: task hung in hashlimit_mt_check_common run #7: crashed: INFO: task hung in htable_put run #8: crashed: INFO: task hung in hashlimit_mt_check_common run #9: crashed: INFO: task hung in hashlimit_mt_check_common testing release v5.3 testing commit 4d856f72c10ecb060868ed10ff1b1453943fc6c8 with gcc (GCC) 8.1.0 kernel signature: a0819ef74dd2adc7bf0eaa3e834291bacb75f65fa3335768dd2de6d7f951c67b 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" "/tmp/syz-executor028062688" "root@10.128.10.39:./syz-executor028062688"]: exit status 1 Connection timed out during banner exchange lost connection run #1: crashed: INFO: task hung in htable_put run #2: crashed: INFO: task hung in htable_put run #3: crashed: INFO: task hung in htable_put run #4: crashed: INFO: task hung in htable_put run #5: crashed: INFO: task hung in hashlimit_mt_check_common run #6: crashed: INFO: task hung in hashlimit_mt_check_common run #7: crashed: INFO: task hung in htable_put run #8: crashed: INFO: task hung in htable_put run #9: crashed: INFO: task hung in htable_put testing release v5.2 testing commit 0ecfebd2b52404ae0c54a878c872bb93363ada36 with gcc (GCC) 8.1.0 kernel signature: 5e74d37e3a158126fc6cd00bfc0c3145870e6ece207e5eeca093744ab4a9ab17 all runs: crashed: INFO: task hung in htable_put testing release v5.1 testing commit e93c9c99a629c61837d5a7fc2120cd2b6c70dbdd with gcc (GCC) 8.1.0 kernel signature: dfb2541c01e740aaaf78cc3ff76c65e2f73139fa97cafca6abe3868e340724b9 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" "/tmp/syz-executor960877641" "root@10.128.10.13:./syz-executor960877641"]: exit status 1 Connection timed out during banner exchange lost connection run #1: crashed: INFO: task hung in htable_put run #2: crashed: INFO: task hung in htable_put run #3: crashed: INFO: task hung in drain_all_pages run #4: crashed: INFO: task hung in htable_put run #5: crashed: INFO: task hung in htable_put run #6: crashed: INFO: task hung in htable_put run #7: crashed: INFO: task hung in htable_put run #8: crashed: INFO: task hung in htable_put run #9: crashed: INFO: task hung in htable_put testing release v5.0 testing commit 1c163f4c7b3f621efff9b28a47abb36f7378d783 with gcc (GCC) 8.1.0 kernel signature: 197d2848c4a85f7df7824b49a6ab44d50596c9083964d5fef7463718ad039ef6 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" "/tmp/syz-executor467147107" "root@10.128.0.156:./syz-executor467147107"]: exit status 1 Connection timed out during banner exchange 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" "/tmp/syz-executor827546982" "root@10.128.1.58:./syz-executor827546982"]: exit status 1 Connection timed out during banner exchange lost connection run #2: crashed: INFO: task hung in htable_put run #3: crashed: INFO: task hung in htable_put run #4: crashed: INFO: task hung in htable_put run #5: crashed: INFO: task hung in htable_put run #6: crashed: INFO: task hung in htable_put run #7: crashed: INFO: task hung in htable_put run #8: crashed: INFO: task hung in htable_put run #9: crashed: INFO: task hung in htable_put testing release v4.20 testing commit 8fe28cb58bcb235034b64cbbb7550a8a43fd88be with gcc (GCC) 8.1.0 kernel signature: da856eee01d7232d6cd6ff4acaddd001282fb3b666568b76bc8fda358e0a02d7 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" "/tmp/syz-executor100126600" "root@10.128.15.198:./syz-executor100126600"]: exit status 1 Connection timed out during banner exchange lost connection run #1: crashed: INFO: task hung in htable_put run #2: crashed: INFO: task hung in htable_put run #3: crashed: INFO: task hung in drain_all_pages run #4: crashed: INFO: task hung in htable_put run #5: crashed: INFO: task hung in htable_put run #6: crashed: INFO: task hung in htable_put run #7: crashed: INFO: task hung in htable_put run #8: crashed: INFO: task hung in drain_all_pages run #9: crashed: INFO: task hung in htable_put testing release v4.19 testing commit 84df9525b0c27f3ebc2ebb1864fa62a97fdedb7d with gcc (GCC) 8.1.0 kernel signature: 7a4e93fdfc6c75e54862a383fd18507171bcd40b0c23edb95157a48098b03452 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" "/tmp/syz-executor637029882" "root@10.128.0.193:./syz-executor637029882"]: exit status 1 ssh: connect to host 10.128.0.193 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" "/tmp/syz-executor601802513" "root@10.128.10.57:./syz-executor601802513"]: exit status 1 Connection timed out during banner exchange lost connection run #2: 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" "/tmp/syz-executor119409468" "root@10.128.0.222:./syz-executor119409468"]: exit status 1 Connection timed out during banner exchange lost connection run #3: crashed: INFO: task hung in htable_put run #4: crashed: INFO: task hung in htable_put run #5: crashed: INFO: task hung in htable_put run #6: crashed: INFO: task hung in htable_put run #7: crashed: INFO: task hung in htable_put run #8: crashed: INFO: task hung in drain_all_pages run #9: crashed: INFO: task hung in htable_put testing release v4.18 testing commit 94710cac0ef4ee177a63b5227664b38c95bbf703 with gcc (GCC) 8.1.0 kernel signature: c2d7d91d6b73d6a77322f420abc659a0f49c910975c31b0b4ff8a0d369075f38 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" "/tmp/syz-executor373694414" "root@10.128.1.7:./syz-executor373694414"]: exit status 1 ssh: connect to host 10.128.1.7 port 22: Connection timed out lost connection run #1: crashed: BUG: workqueue lockup run #2: crashed: BUG: workqueue lockup run #3: crashed: BUG: workqueue lockup run #4: crashed: BUG: workqueue lockup run #5: crashed: BUG: workqueue lockup run #6: crashed: BUG: workqueue lockup run #7: crashed: BUG: workqueue lockup run #8: crashed: BUG: workqueue lockup run #9: crashed: BUG: workqueue lockup testing release v4.17 testing commit 29dcea88779c856c7dc92040a0c01233263101d4 with gcc (GCC) 8.1.0 kernel signature: 9b3597d428d59cc8c49cd6a93f8b89368d8bb222771d5fa1a2776a3b1a1e8b54 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" "/tmp/syz-executor594492976" "root@10.128.0.88:./syz-executor594492976"]: exit status 1 ssh: connect to host 10.128.0.88 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" "/tmp/syz-executor854684111" "root@10.128.0.178:./syz-executor854684111"]: exit status 1 Connection timed out during banner exchange lost connection run #2: crashed: BUG: workqueue lockup run #3: crashed: BUG: workqueue lockup run #4: crashed: INFO: task hung in htable_put run #5: crashed: BUG: workqueue lockup run #6: crashed: BUG: workqueue lockup run #7: crashed: BUG: workqueue lockup run #8: crashed: BUG: workqueue lockup run #9: crashed: BUG: workqueue lockup testing release v4.16 testing commit 0adb32858b0bddf4ada5f364a84ed60b196dbcda with gcc (GCC) 8.1.0 kernel signature: 0c6a31cbe8c6c2fd4f5359443a87d299fce3f083e81d1b2c57eaa19cf4d2bc30 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" "/tmp/syz-executor437206745" "root@10.128.0.208:./syz-executor437206745"]: exit status 1 Connection timed out during banner exchange lost connection run #1: crashed: INFO: task hung in htable_put run #2: crashed: INFO: task hung in htable_put run #3: crashed: INFO: task hung in htable_put run #4: crashed: INFO: task hung in htable_put run #5: crashed: INFO: task hung in htable_put run #6: crashed: INFO: task hung in htable_put run #7: crashed: INFO: task hung in htable_put run #8: crashed: INFO: task hung in htable_put run #9: crashed: INFO: task hung in htable_put testing release v4.15 testing commit d8a5b80568a9cb66810e75b182018e9edb68e8ff with gcc (GCC) 8.1.0 kernel signature: de66e418c785ca8ba60cb914df1add310dcf08a63d28d6c0b157effdea738d41 all runs: crashed: BUG: workqueue lockup testing release v4.14 testing commit bebc6082da0a9f5d47a1ea2edc099bf671058bd4 with gcc (GCC) 8.1.0 kernel signature: 56f8c14143da7fe817d3bc35a07a2612509c0280c645c1c5c52050b666d9c41c run #0: crashed: BUG: workqueue lockup run #1: crashed: BUG: workqueue lockup run #2: crashed: BUG: workqueue lockup run #3: crashed: BUG: workqueue lockup run #4: crashed: BUG: workqueue lockup run #5: crashed: BUG: workqueue lockup run #6: crashed: BUG: workqueue lockup run #7: crashed: INFO: task hung in corrupted run #8: crashed: BUG: workqueue lockup run #9: crashed: BUG: workqueue lockup testing release v4.13 testing commit 569dbb88e80deb68974ef6fdd6a13edb9d686261 with gcc (GCC) 8.1.0 kernel signature: 7802fce9198f4d58dcb680ff5fc7e50781435844907cfc15d30f238ae596dda4 all runs: OK # git bisect start bebc6082da0a9f5d47a1ea2edc099bf671058bd4 569dbb88e80deb68974ef6fdd6a13edb9d686261 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 kernel signature: 2d1fefca7d119b1684313a6d7eb6737f79e28cd1703fb9e9117c4de1ef7a0f91 all runs: OK # git bisect good 15d8ffc96464f6571ecf22043c45fad659f11bdd Bisecting: 3465 revisions left to test after this (roughly 12 steps) [e90937e756938f03d37d4cae7c82316a3a425944] Merge tag 'armsoc-devicetree' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc testing commit e90937e756938f03d37d4cae7c82316a3a425944 with gcc (GCC) 8.1.0 kernel signature: 469d6a9a8e1b782849e441832ff3a2b946ce016f93665fabf9463bae50cbdb71 all runs: OK # git bisect good e90937e756938f03d37d4cae7c82316a3a425944 Bisecting: 1724 revisions left to test after this (roughly 11 steps) [a3583202e8292540fae38ed44bd49d77e35286c2] Merge tag 'drm-fixes-for-v4.14-rc3' of git://people.freedesktop.org/~airlied/linux testing commit a3583202e8292540fae38ed44bd49d77e35286c2 with gcc (GCC) 8.1.0 kernel signature: 27042228f9c8ac0094e6c8d00d6fda5a98fae7f18e6f095e1fdc8693f37803c0 all runs: OK # git bisect good a3583202e8292540fae38ed44bd49d77e35286c2 Bisecting: 861 revisions left to test after this (roughly 10 steps) [2cb3a34abd035756f9ba3cde12f44f4b3e4c234b] Merge tag 'drm-intel-fixes-2017-10-18-1' of git://anongit.freedesktop.org/drm/drm-intel into drm-fixes testing commit 2cb3a34abd035756f9ba3cde12f44f4b3e4c234b with gcc (GCC) 8.1.0 kernel signature: 48c2bf745f60d6b80598821cb25fd4465a9e7b65e26aae8008944aec276f1377 run #0: crashed: BUG: workqueue lockup run #1: crashed: INFO: task hung in corrupted run #2: crashed: BUG: workqueue lockup run #3: crashed: BUG: workqueue lockup run #4: crashed: BUG: workqueue lockup run #5: crashed: INFO: task hung in corrupted run #6: crashed: BUG: workqueue lockup run #7: crashed: BUG: workqueue lockup run #8: crashed: BUG: workqueue lockup run #9: crashed: BUG: workqueue lockup # git bisect bad 2cb3a34abd035756f9ba3cde12f44f4b3e4c234b Bisecting: 431 revisions left to test after this (roughly 9 steps) [00a534e5ea5c21b95f58cbb2f7918cc9fa82dd47] doc: Fix typo "8023.ad" in bonding documentation testing commit 00a534e5ea5c21b95f58cbb2f7918cc9fa82dd47 with gcc (GCC) 8.1.0 kernel signature: f009f9033e94a43e78c6fa2ab54d665df03d58102a0e1ad2c9b6f629728ae6e2 all runs: OK # git bisect good 00a534e5ea5c21b95f58cbb2f7918cc9fa82dd47 Bisecting: 216 revisions left to test after this (roughly 8 steps) [cc74613b13c95c842b47251c7b8788781a967503] Merge tag 'pinctrl-v4.14-3' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl testing commit cc74613b13c95c842b47251c7b8788781a967503 with gcc (GCC) 8.1.0 kernel signature: e3c89b47d69fe9c72008dc0c48be079f1e798d11e225ac38ae41b4c13969ba6b all runs: OK # git bisect good cc74613b13c95c842b47251c7b8788781a967503 Bisecting: 96 revisions left to test after this (roughly 7 steps) [9aa0d2dde6ebd14e9d16e28081a24721d5b41cc8] Merge tag 'drm-fixes-for-v4.14-rc5' of git://people.freedesktop.org/~airlied/linux testing commit 9aa0d2dde6ebd14e9d16e28081a24721d5b41cc8 with gcc (GCC) 8.1.0 kernel signature: fe5fc5d5bfe132002fdfb4d65e14bfe49435335bb9d35240d643f45cc5baf78e run #0: crashed: INFO: task hung in corrupted run #1: crashed: BUG: workqueue lockup run #2: crashed: BUG: workqueue lockup run #3: crashed: BUG: workqueue lockup run #4: crashed: BUG: workqueue lockup run #5: crashed: BUG: workqueue lockup run #6: crashed: INFO: task hung in corrupted run #7: crashed: BUG: workqueue lockup run #8: crashed: BUG: workqueue lockup run #9: crashed: BUG: workqueue lockup # git bisect bad 9aa0d2dde6ebd14e9d16e28081a24721d5b41cc8 Bisecting: 62 revisions left to test after this (roughly 6 steps) [3be5f884f60e9ac66f38c11d92929ba367a86cdb] Merge tag 'for-linus-4.14c-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip testing commit 3be5f884f60e9ac66f38c11d92929ba367a86cdb with gcc (GCC) 8.1.0 kernel signature: e953bb2d93019efd458dfa2532d969c1accd2bf67ea794d125190d3c9901843e all runs: OK # git bisect good 3be5f884f60e9ac66f38c11d92929ba367a86cdb Bisecting: 31 revisions left to test after this (roughly 5 steps) [ca182551857cc2c1e6a2b7f1e72090a137a15008] kmemleak: clear stale pointers from task stacks testing commit ca182551857cc2c1e6a2b7f1e72090a137a15008 with gcc (GCC) 8.1.0 kernel signature: fbcccb8c205d61c9571dabca340a005775d0d150f41dbf7ac8bf81c88ab32ab3 run #0: crashed: BUG: workqueue lockup run #1: crashed: BUG: workqueue lockup run #2: crashed: BUG: workqueue lockup run #3: crashed: BUG: workqueue lockup run #4: crashed: BUG: workqueue lockup run #5: crashed: BUG: workqueue lockup run #6: crashed: BUG: workqueue lockup run #7: crashed: BUG: workqueue lockup run #8: crashed: INFO: task hung in corrupted run #9: crashed: BUG: workqueue lockup # git bisect bad ca182551857cc2c1e6a2b7f1e72090a137a15008 Bisecting: 15 revisions left to test after this (roughly 4 steps) [997301a860fca1a05ab8e383a8039b65f8abeb1e] Merge tag 'iommu-fixes-v4.14-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu testing commit 997301a860fca1a05ab8e383a8039b65f8abeb1e with gcc (GCC) 8.1.0 kernel signature: 5bf4a6cf0e12f4158b8cfc3f351a389dc549abd439cbafd120e56f2dcf1474d7 all runs: OK # git bisect good 997301a860fca1a05ab8e383a8039b65f8abeb1e Bisecting: 7 revisions left to test after this (roughly 3 steps) [7ddd8faf4399ab4f4edad5604eab35f8a87caf02] userfaultfd: selftest: exercise -EEXIST only in background transfer testing commit 7ddd8faf4399ab4f4edad5604eab35f8a87caf02 with gcc (GCC) 8.1.0 kernel signature: 82f94525dd04aec33053547b5ff78889a6bf050e82e15c612ed5c60a9c0a1b0e run #0: crashed: WARNING: ODEBUG bug in netdev_freemem 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 7ddd8faf4399ab4f4edad5604eab35f8a87caf02 Bisecting: 3 revisions left to test after this (roughly 2 steps) [8a1ac5dc7be09883051b1bf89a5e57d7ad850fa5] include/linux/of.h: provide of_n_{addr,size}_cells wrappers for !CONFIG_OF testing commit 8a1ac5dc7be09883051b1bf89a5e57d7ad850fa5 with gcc (GCC) 8.1.0 kernel signature: d14490a431ffb5242d19aa6a1126f3dee1f0ffff8d5e95bb7220acab1c205be0 all runs: OK # git bisect good 8a1ac5dc7be09883051b1bf89a5e57d7ad850fa5 Bisecting: 1 revision left to test after this (roughly 1 step) [af0db981f35ea99b00a0b249bf0bedef8cf972e8] mm: remove unnecessary WARN_ONCE in page_vma_mapped_walk(). testing commit af0db981f35ea99b00a0b249bf0bedef8cf972e8 with gcc (GCC) 8.1.0 kernel signature: 257189182c2bcf3befc8d4b7dcd948913a201130143d2e290a0fbf339bd7f558 all runs: OK # git bisect good af0db981f35ea99b00a0b249bf0bedef8cf972e8 Bisecting: 0 revisions left to test after this (roughly 0 steps) [064f0e9302af4f4ab5e9dca03a5a77d6bebfd35e] mm: only display online cpus of the numa node testing commit 064f0e9302af4f4ab5e9dca03a5a77d6bebfd35e with gcc (GCC) 8.1.0 kernel signature: 2abde71be966c1b9ae90fb039980f97562b369d49ea4ab51840ba8502414cea5 all runs: OK # git bisect good 064f0e9302af4f4ab5e9dca03a5a77d6bebfd35e 7ddd8faf4399ab4f4edad5604eab35f8a87caf02 is the first bad commit commit 7ddd8faf4399ab4f4edad5604eab35f8a87caf02 Author: Andrea Arcangeli Date: Fri Oct 13 15:57:54 2017 -0700 userfaultfd: selftest: exercise -EEXIST only in background transfer I was stress testing some backports and with high load, after some time, the latest version of the selftest showed some false positive in connection with the uffdio_copy_retry. This seems to fix it while still exercising -EEXIST in the background transfer once in a while. The fork child will quit after the last UFFDIO_COPY is run, so a repeated UFFDIO_COPY may not return -EEXIST. This change restricts the -EEXIST stress to the background transfer where the memory can't go away from under it. Also updated uffdio_zeropage, so the interface is consistent. Link: http://lkml.kernel.org/r/20171004171541.1495-2-aarcange@redhat.com Signed-off-by: Andrea Arcangeli Cc: Pavel Emelyanov Cc: Mike Rapoport Cc: "Dr. David Alan Gilbert" Cc: Mike Kravetz Cc: Shuah Khan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds tools/testing/selftests/vm/userfaultfd.c | 25 ++++++++++++++++++++----- 1 file changed, 20 insertions(+), 5 deletions(-) culprit signature: 82f94525dd04aec33053547b5ff78889a6bf050e82e15c612ed5c60a9c0a1b0e parent signature: 2abde71be966c1b9ae90fb039980f97562b369d49ea4ab51840ba8502414cea5 revisions tested: 28, total time: 6h58m2.905779566s (build: 2h41m6.926200384s, test: 4h14m31.08127918s) first bad commit: 7ddd8faf4399ab4f4edad5604eab35f8a87caf02 userfaultfd: selftest: exercise -EEXIST only in background transfer cc: ["aarcange@redhat.com" "akpm@linux-foundation.org" "torvalds@linux-foundation.org"] crash: WARNING: ODEBUG bug in netdev_freemem bond0 (unregistering): Releasing backup interface bond_slave_1 bond0 (unregistering): Releasing backup interface bond_slave_0 bond0 (unregistering): Released all slaves ODEBUG: free active (active state 0) object type: timer_list hint: delayed_work_timer_fn+0x0/0x90 kernel/workqueue.c:4806 ------------[ cut here ]------------ WARNING: CPU: 0 PID: 8059 at lib/debugobjects.c:291 debug_print_object.cold.14+0xa7/0xdb lib/debugobjects.c:288 Kernel panic - not syncing: panic_on_warn set ... CPU: 0 PID: 8059 Comm: kworker/u4:6 Not tainted 4.14.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: netns cleanup_net Call Trace: __dump_stack lib/dump_stack.c:16 [inline] dump_stack+0x145/0x1e1 lib/dump_stack.c:52 panic+0x1a9/0x34e kernel/panic.c:181 __warn.cold.8+0x11a/0x156 kernel/panic.c:542 report_bug+0x1a3/0x227 lib/bug.c:183 fixup_bug arch/x86/kernel/traps.c:178 [inline] do_trap_no_signal arch/x86/kernel/traps.c:212 [inline] do_trap+0x1ef/0x2d0 arch/x86/kernel/traps.c:261 do_error_trap+0x11f/0x390 arch/x86/kernel/traps.c:298 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:311 invalid_op+0x18/0x20 arch/x86/entry/entry_64.S:905 RIP: 0010:debug_print_object.cold.14+0xa7/0xdb lib/debugobjects.c:288 RSP: 0018:ffff88010da7ea58 EFLAGS: 00010082 RAX: 0000000000000061 RBX: 0000000000000003 RCX: 0000000000000000 RDX: 0000000000000061 RSI: ffffffff878bd580 RDI: ffffed0021b4fd42 RBP: ffff88010da7ea80 R08: 1ffff10021b4fcd9 R09: ffff88010bb42440 R10: 0000000000000000 R11: dffffc0000000000 R12: ffffffff878b8780 R13: ffffffff81453770 R14: 0000000000000000 R15: ffff88010da7ec28 __debug_check_no_obj_freed lib/debugobjects.c:745 [inline] debug_check_no_obj_freed+0x643/0xcc3 lib/debugobjects.c:774 kfree+0xbd/0x270 mm/slab.c:3819 kvfree+0x2c/0x30 mm/util.c:416 netdev_freemem+0x47/0x60 net/core/dev.c:7975 netdev_release+0x6a/0x80 net/core/net-sysfs.c:1492 device_release+0x134/0x170 drivers/base/core.c:814 kobject_cleanup lib/kobject.c:648 [inline] kobject_release lib/kobject.c:677 [inline] kref_put include/linux/kref.h:70 [inline] kobject_put+0x107/0x1b0 lib/kobject.c:694 netdev_run_todo+0x883/0xb70 net/core/dev.c:7880 rtnl_unlock+0x9/0x10 net/core/rtnetlink.c:106 default_device_exit_batch+0x3d0/0x500 net/core/dev.c:8664 ops_exit_list.isra.8+0xd3/0x120 net/core/net_namespace.c:145 cleanup_net+0x55b/0xaa0 net/core/net_namespace.c:483 process_one_work+0x9f7/0x1a80 kernel/workqueue.c:2119 worker_thread+0x215/0x1820 kernel/workqueue.c:2253 kthread+0x376/0x440 kernel/kthread.c:231 ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:431 ======================================================