bisecting cause commit starting from 990f227371a400c0fbcb98b75c91a7dbd65f6132 building syzkaller on 54ce1ed6b9fcb3b8d77c43dd4b3533e70cade414 testing commit 990f227371a400c0fbcb98b75c91a7dbd65f6132 with gcc (GCC) 8.1.0 kernel signature: e5f978faf4aaefa93e45abb0011571c11a7aaf2dd8b80ce5edbb77926d91ccdc all runs: crashed: BUG: unable to handle kernel NULL pointer dereference in x86_fsgsbase_read_task testing release v5.8 testing commit bcf876870b95592b52519ed4aafcf9d95999bc9c with gcc (GCC) 8.1.0 kernel signature: e6b7f9fd7a02b818c0a220721b0158320d99c34a1b2a78f9b6c75818e008eeb4 all runs: OK # git bisect start 990f227371a400c0fbcb98b75c91a7dbd65f6132 bcf876870b95592b52519ed4aafcf9d95999bc9c Bisecting: 7198 revisions left to test after this (roughly 13 steps) [8186749621ed6b8fc42644c399e8c755a2b6f630] Merge tag 'drm-next-2020-08-06' of git://anongit.freedesktop.org/drm/drm testing commit 8186749621ed6b8fc42644c399e8c755a2b6f630 with gcc (GCC) 8.1.0 kernel signature: 880ba7a5f6174bdd7e4801a68bef361618c36a5d649bdb5eb7af2c48bb77a05f all runs: crashed: BUG: unable to handle kernel NULL pointer dereference in x86_fsgsbase_read_task # git bisect bad 8186749621ed6b8fc42644c399e8c755a2b6f630 Bisecting: 2954 revisions left to test after this (roughly 12 steps) [2324d50d051ec0f14a548e78554fb02513d6dcef] Merge tag 'docs-5.9' of git://git.lwn.net/linux testing commit 2324d50d051ec0f14a548e78554fb02513d6dcef with gcc (GCC) 8.1.0 kernel signature: 4b611afc6a3f3f7b56ce92e1cf07e706e747ed5b80a7aae7a179a614fa191283 all runs: crashed: BUG: unable to handle kernel NULL pointer dereference in x86_fsgsbase_read_task # git bisect bad 2324d50d051ec0f14a548e78554fb02513d6dcef Bisecting: 1745 revisions left to test after this (roughly 11 steps) [92c59e126b21fd212195358a0d296e787e444087] Merge tag 'arm-defconfig-5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc testing commit 92c59e126b21fd212195358a0d296e787e444087 with gcc (GCC) 8.1.0 kernel signature: de2ab9f3d073d05d8f6f44d3380e55a972e12838fc7e5acfad0f6fdd723ee334 all runs: OK # git bisect good 92c59e126b21fd212195358a0d296e787e444087 Bisecting: 853 revisions left to test after this (roughly 10 steps) [d4db4e553249eda9016fab2e363c26e52c47926f] Merge tag 'arm-newsoc-5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc testing commit d4db4e553249eda9016fab2e363c26e52c47926f with gcc (GCC) 8.1.0 kernel signature: 9df555f412fefd0ad098d20d49ee01a55cc4ec64c12e358f0f57eee1f117ed74 all runs: OK # git bisect good d4db4e553249eda9016fab2e363c26e52c47926f Bisecting: 428 revisions left to test after this (roughly 9 steps) [fd76a74d940ae3d6b8b2395cd12914630c7e1739] Merge tag 'audit-pr-20200803' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit testing commit fd76a74d940ae3d6b8b2395cd12914630c7e1739 with gcc (GCC) 8.1.0 kernel signature: 26f7e210476e28c226b1a822f2cdbf295768512d59b6cf74d686a1d696c770c0 all runs: OK # git bisect good fd76a74d940ae3d6b8b2395cd12914630c7e1739 Bisecting: 212 revisions left to test after this (roughly 8 steps) [95ffa676583b23baed40861d30b65fe31397da00] Merge branch 'parisc-5.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux testing commit 95ffa676583b23baed40861d30b65fe31397da00 with gcc (GCC) 8.1.0 kernel signature: 180fefbe21ee31f482557734f89095b63c28969e67b82a6be5e2af1896e3d893 all runs: crashed: BUG: unable to handle kernel NULL pointer dereference in x86_fsgsbase_read_task # git bisect bad 95ffa676583b23baed40861d30b65fe31397da00 Bisecting: 89 revisions left to test after this (roughly 7 steps) [f8b036a7fc231fe6e8297daddee5dffdbbf2581f] Merge tag 'irq-core-2020-08-04' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip testing commit f8b036a7fc231fe6e8297daddee5dffdbbf2581f with gcc (GCC) 8.1.0 kernel signature: b8bf4d5cf79fb0d765b442133c3d18f82d20a8f69bf14525c4c47820eed839c2 all runs: OK # git bisect good f8b036a7fc231fe6e8297daddee5dffdbbf2581f Bisecting: 51 revisions left to test after this (roughly 6 steps) [3f0d6ecdf1ab35ac54cabb759f748fb0bffd26a5] Merge tag 'core-entry-2020-08-04' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip testing commit 3f0d6ecdf1ab35ac54cabb759f748fb0bffd26a5 with gcc (GCC) 8.1.0 kernel signature: 82155a7d5257a1fe5e0342572882bb7889f6e3f5ddc4b435d32458ecb5e7b9b3 all runs: OK # git bisect good 3f0d6ecdf1ab35ac54cabb759f748fb0bffd26a5 Bisecting: 30 revisions left to test after this (roughly 5 steps) [d029bff60aa6c7eab281d52602b6a7a971615324] x86/fsgsbase: Fix Xen PV support testing commit d029bff60aa6c7eab281d52602b6a7a971615324 with gcc (GCC) 8.1.0 kernel signature: 86328c7a4311c51fb05f218de5280352800d77d139208ea8aee0f10479f12ea1 all runs: basic kernel testing failed: BUG: using smp_processor_id() in preemptible code in ext4_mb_new_blocks # git bisect skip d029bff60aa6c7eab281d52602b6a7a971615324 Bisecting: 30 revisions left to test after this (roughly 5 steps) [adb334d17858d8b679a41f7f2cd230e5c6accc0a] Merge branch 'WIP.x86/entry' into x86/entry, to merge the latest generic code and resolve conflicts testing commit adb334d17858d8b679a41f7f2cd230e5c6accc0a with gcc (GCC) 8.1.0 ./include/linux/irqflags.h:40:41: error: expected expression before ')' token # git bisect skip adb334d17858d8b679a41f7f2cd230e5c6accc0a Bisecting: 30 revisions left to test after this (roughly 5 steps) [005f141e5d5e05d3986539567d0bc5aa2f4dc640] x86/process/64: Use FSGSBASE instructions on thread copy and ptrace testing commit 005f141e5d5e05d3986539567d0bc5aa2f4dc640 with gcc (GCC) 8.1.0 kernel signature: 3d78d65aefccdaf602fd67b4b223c22a33782ae8255d39513b198243b4ab9a86 all runs: basic kernel testing failed: BUG: using smp_processor_id() in preemptible code in ext4_mb_new_blocks # git bisect skip 005f141e5d5e05d3986539567d0bc5aa2f4dc640 Bisecting: 30 revisions left to test after this (roughly 5 steps) [979c2c4247cafd8a91628a7306b6871efbd12fdb] selftests/x86/fsgsbase: Fix a comment in the ptrace_write_gsbase test testing commit 979c2c4247cafd8a91628a7306b6871efbd12fdb with gcc (GCC) 8.1.0 kernel signature: 59171e421b6e8546fbc00ab8b5210adcd7d54ed8905fdcb140d35fd3e9d898da all runs: basic kernel testing failed: BUG: using smp_processor_id() in preemptible code in ext4_mb_new_blocks # git bisect skip 979c2c4247cafd8a91628a7306b6871efbd12fdb Bisecting: 30 revisions left to test after this (roughly 5 steps) [157e9afcc4fa25068b0e8743bc254a9b56010e13] Revert "parisc: Revert "Release spinlocks using ordered store"" testing commit 157e9afcc4fa25068b0e8743bc254a9b56010e13 with gcc (GCC) 8.1.0 kernel signature: 4f838550b58720ab05dd91d9f2035e6b62624bfdc0193d96d32e6aebedc36f91 run #0: crashed: WARNING in ptrace_stop run #1: crashed: WARNING in ptrace_stop run #2: crashed: WARNING in ptrace_stop run #3: crashed: WARNING in ptrace_stop run #4: OK run #5: OK run #6: crashed: WARNING in ptrace_stop run #7: OK run #8: OK run #9: OK # git bisect bad 157e9afcc4fa25068b0e8743bc254a9b56010e13 Bisecting: 3 revisions left to test after this (roughly 2 steps) [693a06543379709a7c20a9a6d04f005cf00572f9] parisc: Replace HTTP links with HTTPS ones testing commit 693a06543379709a7c20a9a6d04f005cf00572f9 with gcc (GCC) 8.1.0 kernel signature: 5f6ad9763d15fb0586f19ca869526711a8b43a68c5a82ac540151679bd520523 run #0: crashed: WARNING in ptrace_stop run #1: crashed: WARNING in ptrace_stop run #2: crashed: WARNING in ptrace_stop run #3: crashed: WARNING in ptrace_stop run #4: OK run #5: OK run #6: OK run #7: OK run #8: crashed: WARNING in ptrace_stop run #9: crashed: WARNING in ptrace_stop # git bisect bad 693a06543379709a7c20a9a6d04f005cf00572f9 Bisecting: 1 revision left to test after this (roughly 1 step) [0e5a7ff6e36ad58933d076ddcac36ff14d014692] parisc: Report bad pages as HardwareCorrupted testing commit 0e5a7ff6e36ad58933d076ddcac36ff14d014692 with gcc (GCC) 8.1.0 kernel signature: f2595a7ebafcc4130643057a20d58f75469cfd441a991ae6ba7722c6d3a8a7ff run #0: crashed: WARNING in ptrace_stop run #1: crashed: WARNING in ptrace_stop run #2: crashed: WARNING in ptrace_stop run #3: crashed: WARNING in ptrace_stop run #4: crashed: WARNING in ptrace_stop run #5: boot failed: can't ssh into the instance run #6: OK run #7: boot failed: can't ssh into the instance run #8: OK run #9: OK # git bisect bad 0e5a7ff6e36ad58933d076ddcac36ff14d014692 Bisecting: 0 revisions left to test after this (roughly 0 steps) [208151bfb70fb7fb39959998832f7b5879be4751] parisc: Convert to BIT_MASK() and BIT_WORD() testing commit 208151bfb70fb7fb39959998832f7b5879be4751 with gcc (GCC) 8.1.0 kernel signature: f2cae9d6ad02ddd52352d95cf0f7ae601da576c92f4ea97e6846f7d227b9b0e6 run #0: crashed: WARNING in ptrace_stop run #1: crashed: WARNING in ptrace_stop run #2: crashed: WARNING in ptrace_stop run #3: crashed: WARNING in ptrace_stop run #4: crashed: WARNING in ptrace_stop run #5: crashed: WARNING in ptrace_stop run #6: crashed: WARNING in ptrace_stop run #7: OK run #8: OK run #9: crashed: WARNING in ptrace_stop # git bisect bad 208151bfb70fb7fb39959998832f7b5879be4751 208151bfb70fb7fb39959998832f7b5879be4751 is the first bad commit commit 208151bfb70fb7fb39959998832f7b5879be4751 Author: Helge Deller Date: Sun Jun 14 10:54:10 2020 +0200 parisc: Convert to BIT_MASK() and BIT_WORD() Drop own open-coded implementation to set bits and use the kernel provided BIT_MASK() and BIT_WORD() macros. Signed-off-by: Helge Deller arch/parisc/include/asm/bitops.h | 41 +++++++++++++--------------------------- arch/parisc/mm/init.c | 12 ++++++------ 2 files changed, 19 insertions(+), 34 deletions(-) parent commit ba47d845d715a010f7b51f6f89bae32845e6acb7 wasn't tested testing commit ba47d845d715a010f7b51f6f89bae32845e6acb7 with gcc (GCC) 8.1.0 kernel signature: 5fc3925c9ce4b5e5565a82da8a837472903831311337c7384278d5e7412eaba4 culprit signature: f2cae9d6ad02ddd52352d95cf0f7ae601da576c92f4ea97e6846f7d227b9b0e6 parent signature: 5fc3925c9ce4b5e5565a82da8a837472903831311337c7384278d5e7412eaba4 revisions tested: 18, total time: 3h49m49.092334437s (build: 1h35m43.006157059s, test: 2h12m18.408044694s) first bad commit: 208151bfb70fb7fb39959998832f7b5879be4751 parisc: Convert to BIT_MASK() and BIT_WORD() recipients (to): ["James.Bottomley@HansenPartnership.com" "deller@gmx.de" "deller@gmx.de" "linux-parisc@vger.kernel.org"] recipients (cc): ["akpm@linux-foundation.org" "linux-kernel@vger.kernel.org" "rppt@kernel.org"] crash: WARNING in ptrace_stop ------------[ cut here ]------------ do not call blocking ops when !TASK_RUNNING; state=8 set at [<00000000b3944fd8>] ptrace_stop+0x0/0x2b0 kernel/signal.c:2073 WARNING: CPU: 0 PID: 25327 at kernel/sched/core.c:6888 __might_sleep+0x63/0x70 kernel/sched/core.c:6883 Kernel panic - not syncing: panic_on_warn set ... CPU: 0 PID: 25327 Comm: syz-executor738 Not tainted 5.8.0-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+0xb3/0xec lib/dump_stack.c:118 panic+0x115/0x2fa kernel/panic.c:231 __warn.cold.13+0x20/0x25 kernel/panic.c:600 report_bug+0xc0/0xf0 lib/bug.c:198 handle_bug+0x35/0x90 arch/x86/kernel/traps.c:235 exc_invalid_op+0x13/0x60 arch/x86/kernel/traps.c:255 asm_exc_invalid_op+0x12/0x20 arch/x86/include/asm/idtentry.h:540 RIP: 0010:__might_sleep+0x63/0x70 kernel/sched/core.c:6883 Code: 5b 5d 41 5c e9 7e fe ff ff 48 8b 90 10 14 00 00 48 c7 c7 c8 cf e4 83 c6 05 98 76 3c 03 01 48 8b 70 10 48 89 d1 e8 98 70 fc ff <0f> 0b eb ca 66 0f 1f 84 00 00 00 00 00 89 f6 e9 a9 6e 0e 00 66 0f RSP: 0018:ffffc90006027db8 EFLAGS: 00010286 RAX: 0000000000000000 RBX: ffffffff83e4958e RCX: 0000000000000001 RDX: 0000000080000001 RSI: ffffffff8400db31 RDI: 00000000ffffffff RBP: 0000000000000039 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000004 R14: 0000000000000000 R15: 000000000000003c try_to_freeze_unsafe include/linux/freezer.h:57 [inline] try_to_freeze include/linux/freezer.h:67 [inline] freezer_count include/linux/freezer.h:128 [inline] freezable_schedule include/linux/freezer.h:173 [inline] ptrace_stop+0x160/0x2b0 kernel/signal.c:2215 ptrace_signal kernel/signal.c:2490 [inline] get_signal+0x719/0xcb0 kernel/signal.c:2639 do_signal+0x2b/0x920 arch/x86/kernel/signal.c:810 exit_to_usermode_loop arch/x86/entry/common.c:235 [inline] __prepare_exit_to_usermode+0x1a7/0x210 arch/x86/entry/common.c:269 __do_fast_syscall_32 arch/x86/entry/common.c:475 [inline] do_fast_syscall_32+0x7f/0x120 arch/x86/entry/common.c:503 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c RIP: 0023:0xf7f71569 Code: Bad RIP value. RSP: 002b:00000000ffec98ac EFLAGS: 00000296 ORIG_RAX: 0000000000000072 RAX: fffffffffffffe00 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000040000000 RSI: 0000000000000000 RDI: 00000000ffffffff RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Kernel Offset: disabled Rebooting in 86400 seconds..