bisecting fixing commit since cb95712138ec5e480db5160b41172bbc6f6494cc building syzkaller on cef5ae6814696260ff58c538a1b6044af90c5979 testing commit cb95712138ec5e480db5160b41172bbc6f6494cc with gcc (GCC) 8.4.1 20210217 kernel signature: 9b18ca80919f5801857d441e22eb090b0b0b8a9a34d95381668c75c616aa0623 all runs: crashed: general protection fault in bdev_read_page testing current HEAD f69d02e37a85645aa90d18cacfff36dba370f797 testing commit f69d02e37a85645aa90d18cacfff36dba370f797 with gcc (GCC) 10.2.1 20210217 kernel signature: c6f037802bd321740acb98aa776be972a7cdbf2e7153bd8f3a755456422c0e5a all runs: crashed: general protection fault in bdev_read_page revisions tested: 2, total time: 19m20.791576496s (build: 12m12.596268007s, test: 6m27.309758053s) the crash still happens on HEAD commit msg: Merge tag 'misc-5.12-2021-03-02' of git://git.kernel.dk/linux-block crash: general protection fault in bdev_read_page general protection fault, probably for non-canonical address 0xdffffc00000000c5: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000628-0x000000000000062f] CPU: 1 PID: 7417 Comm: systemd-udevd Not tainted 5.12.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:bdev_read_page+0x2c/0x240 fs/block_dev.c:718 Code: 00 00 00 00 00 fc ff df 41 57 41 56 49 89 d6 41 55 41 54 55 48 8d af 28 06 00 00 48 89 ea 53 48 89 fb 48 c1 ea 03 48 83 ec 10 <80> 3c 02 00 48 89 34 24 0f 85 a3 01 00 00 4c 8b a3 28 06 00 00 48 RSP: 0018:ffffc900044d7448 EFLAGS: 00010286 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000014 RDX: 00000000000000c5 RSI: fff88f26e3000000 RDI: 0000000000000000 RBP: 0000000000000628 R08: 0000000000000001 R09: ffffea0004042c47 R10: fffff94000808588 R11: 0000000000000000 R12: ffffc900044d7658 R13: fff88f26e3000000 R14: ffffea0004042c40 R15: 0000000000000000 FS: 00007f373510b8c0(0000) GS:ffff8881f6500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffc8ea1cd80 CR3: 000000011ac54005 CR4: 00000000001706e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: do_mpage_readpage+0xd59/0x18c0 fs/mpage.c:302 mpage_readahead+0x2c0/0x6c0 fs/mpage.c:389 read_pages+0x1b0/0x7c0 mm/readahead.c:130 page_cache_ra_unbounded+0x443/0x7b0 mm/readahead.c:238 do_page_cache_ra mm/readahead.c:267 [inline] force_page_cache_ra+0x2dd/0x540 mm/readahead.c:298 page_cache_sync_readahead include/linux/pagemap.h:840 [inline] filemap_get_pages+0x248/0x1410 mm/filemap.c:2375 filemap_read+0x261/0xb50 mm/filemap.c:2458 call_read_iter include/linux/fs.h:1971 [inline] new_sync_read+0x35a/0x5f0 fs/read_write.c:415 vfs_read+0x264/0x470 fs/read_write.c:496 ksys_read+0xf4/0x1d0 fs/read_write.c:634 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f3734251210 Code: 73 01 c3 48 8b 0d 98 7d 20 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d b9 c1 20 00 00 75 10 b8 00 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 4e fc ff ff 48 89 04 24 RSP: 002b:00007ffc8ea1f448 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 000055ebd77823a0 RCX: 00007f3734251210 RDX: 0000000000000400 RSI: 000055ebd77823c8 RDI: 000000000000000f RBP: 000055ebd777da40 R08: 00007f373423bf78 R09: 0000000000000430 R10: 000000000000006d R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000400 R14: 000055ebd777da90 R15: 0000000000000400 Modules linked in: ---[ end trace 1ae66ee1b9711ece ]--- RIP: 0010:bdev_read_page+0x2c/0x240 fs/block_dev.c:718 Code: 00 00 00 00 00 fc ff df 41 57 41 56 49 89 d6 41 55 41 54 55 48 8d af 28 06 00 00 48 89 ea 53 48 89 fb 48 c1 ea 03 48 83 ec 10 <80> 3c 02 00 48 89 34 24 0f 85 a3 01 00 00 4c 8b a3 28 06 00 00 48 RSP: 0018:ffffc900044d7448 EFLAGS: 00010286 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000014 RDX: 00000000000000c5 RSI: fff88f26e3000000 RDI: 0000000000000000 RBP: 0000000000000628 R08: 0000000000000001 R09: ffffea0004042c47 R10: fffff94000808588 R11: 0000000000000000 R12: ffffc900044d7658 R13: fff88f26e3000000 R14: ffffea0004042c40 R15: 0000000000000000 FS: 00007f373510b8c0(0000) GS:ffff8881f6400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000536db8 CR3: 000000011ac54001 CR4: 00000000001706f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400