bisecting fixing commit since f4d51dffc6c01a9e94650d95ce0104964f8ae822
building syzkaller on abf9ba4fc75d9b29af15625d44dcfc1360fad3b7
testing commit f4d51dffc6c01a9e94650d95ce0104964f8ae822 with gcc (GCC) 8.1.0
kernel signature: ac350ea5fad10cac802777af247d9489d0b699fd0c5cdade263653edd54dfd9d
run #0: crashed: WARNING in vmacache_find
run #1: crashed: BUG: unable to handle kernel paging request in handle_mm_fault
run #2: crashed: BUG: Bad page map
run #3: crashed: PANIC: double fault in __switch_to_asm
run #4: crashed: BUG: unable to handle kernel paging request in futex_wait
run #5: crashed: BUG: unable to handle kernel NULL pointer dereference in do_swap_page
run #6: crashed: BUG: unable to handle kernel NULL pointer dereference in corrupted
run #7: crashed: BUG: Bad rss-counter state
run #8: crashed: kernel BUG at kernel/futex.c:LINE!
run #9: crashed: INFO: trying to register non-static key in try_to_wake_up
testing current HEAD 583090b1b8232e6eae243a9009699666153a13a9
testing commit 583090b1b8232e6eae243a9009699666153a13a9 with gcc (GCC) 8.1.0
kernel signature: 83df8725ed94e56c00752a426eaad784b2991c9005a6bf705ae54da64fac1252
run #0: crashed: BUG: unable to handle kernel NULL pointer dereference in do_swap_page
run #1: crashed: BUG: unable to handle kernel NULL pointer dereference in set_next_entity
run #2: crashed: BUG: unable to handle kernel paging request in wait_consider_task
run #3: crashed: INFO: trying to register non-static key in __split_huge_pud
run #4: crashed: unexpected kernel reboot
run #5: crashed: BUG: Bad page map
run #6: crashed: general protection fault in psi_task_change
run #7: crashed: unexpected kernel reboot
run #8: crashed: WARNING in vmacache_find
run #9: crashed: BUG: unable to handle kernel NULL pointer dereference in do_swap_page
revisions tested: 2, total time: 23m10.238195159s (build: 9m52.674610699s, test: 12m56.117420362s)
the crash still happens on HEAD
commit msg: Merge tag 'block5.9-2020-10-08' of git://git.kernel.dk/linux-block
crash: BUG: unable to handle kernel NULL pointer dereference in do_swap_page
get_swap_device: Bad swap file entry 3fffc47fffc47
BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 53067 P4D 53067 PUD 74067 PMD 0 
Oops: 0000 [#1] PREEMPT SMP
CPU: 0 PID: 27784 Comm: syz-executor.4 Not tainted 5.9.0-rc8-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:do_swap_page+0x419/0xa60 mm/memory.c:3274
Code: 01 0f 85 89 02 00 00 48 8b 7b 50 e8 d1 54 cb 01 48 8d 65 d8 44 89 f0 5b 41 5c 41 5d 41 5e 41 5f 5d c3 4c 89 e7 e8 67 47 03 00 <48> 8b 00 f6 c4 10 74 11 4c 89 e7 e8 d7 ff 02 00 83 f8 01 0f 84 3b
RSP: 0000:ffffc90004f9fde0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffffc90004f9fe60 RCX: 0000000000000001
RDX: 0000000000000000 RSI: ffffffff8401c171 RDI: 0000000000000000
RBP: ffffc90004f9fe28 R08: 0000000000000001 R09: 0000000000000001
R10: ffff88800008e700 R11: 572dc82d83176e59 R12: 0003fffc47fffc47
R13: ffff8880abffd4b0 R14: 0000000000000000 R15: 0000000000000000
FS:  0000000001fca940(0000) GS:ffff88812c000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 0000000000052000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 handle_pte_fault mm/memory.c:4371 [inline]
 __handle_mm_fault mm/memory.c:4502 [inline]
 handle_mm_fault+0x103c/0x1830 mm/memory.c:4600
 do_user_addr_fault arch/x86/mm/fault.c:1372 [inline]
 handle_page_fault arch/x86/mm/fault.c:1429 [inline]
 exc_page_fault+0x34f/0x720 arch/x86/mm/fault.c:1482
 asm_exc_page_fault+0x1e/0x30 arch/x86/include/asm/idtentry.h:538
RIP: 0033:0x40fb38
Code: 00 00 59 01 0f 82 58 ff ff ff 48 89 c6 b9 00 00 59 01 ba 00 00 19 01 bf e0 1a 4d 00 31 c0 e8 df 39 ff ff 0f 1f 80 00 00 00 00 <80> 3d c1 04 18 01 00 75 06 80 7b 20 00 74 2e 8b 05 b7 04 18 01 c6
RSP: 002b:00007fff91a766d0 EFLAGS: 00010202
RAX: 00000000011900a8 RBX: 000000000118cf40 RCX: 0000000000000001
RDX: 0000000000000001 RSI: 00000000011900b0 RDI: 000000000118cf40
RBP: 000000000118d940 R08: 0000000000000000 R09: 0000000000000000
R10: 00007fff91a767e0 R11: 0000000000000246 R12: 00000000000003e8
R13: 00000000000429c4 R14: 0000000000042997 R15: 000000000118cfec
Modules linked in:
CR2: 0000000000000000
---[ end trace 1f44f188effd6782 ]---
RIP: 0010:do_swap_page+0x419/0xa60 mm/memory.c:3274
Code: 01 0f 85 89 02 00 00 48 8b 7b 50 e8 d1 54 cb 01 48 8d 65 d8 44 89 f0 5b 41 5c 41 5d 41 5e 41 5f 5d c3 4c 89 e7 e8 67 47 03 00 <48> 8b 00 f6 c4 10 74 11 4c 89 e7 e8 d7 ff 02 00 83 f8 01 0f 84 3b
RSP: 0000:ffffc90004f9fde0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffffc90004f9fe60 RCX: 0000000000000001
RDX: 0000000000000000 RSI: ffffffff8401c171 RDI: 0000000000000000
RBP: ffffc90004f9fe28 R08: 0000000000000001 R09: 0000000000000001
R10: ffff88800008e700 R11: 572dc82d83176e59 R12: 0003fffc47fffc47
R13: ffff8880abffd4b0 R14: 0000000000000000 R15: 0000000000000000
FS:  0000000001fca940(0000) GS:ffff88812c000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 0000000000052000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400