syzbot


WARNING in hpage_collapse_scan_pmd (2)

Status: auto-obsoleted due to no activity on 2024/08/29 16:10
Subsystems: mm
[Documentation on labels]
Reported-by: syzbot+5ea2845f44caa77f5543@syzkaller.appspotmail.com
First crash: 236d, last: 228d
Cause bisection: introduced by (bisect log) :
commit ef5b6a542b1dbb718226a5f8208be09ef405983d
Author: Paolo Bonzini <pbonzini@redhat.com>
Date: Wed Nov 8 09:40:35 2023 +0000

  selftests: kvm/s390x: use vm_create_barebones()

Crash: WARNING in hpage_collapse_scan_pmd (log)
Repro: syz .config
  
Fix bisection: fixed by (bisect log) :
commit c88033efe9a391e72ba6b5df4b01d6e628f4e734
Author: Peter Xu <peterx@redhat.com>
Date: Mon Apr 22 13:33:11 2024 +0000

  mm/userfaultfd: reset ptes when close() for wr-protected ones

  
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [mm?] [io-uring?] WARNING in hpage_collapse_scan_pmd (2) 1 (5) 2024/08/15 16:10
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream WARNING in hpage_collapse_scan_pmd mm 1 352d 347d 0/28 auto-obsoleted due to no activity on 2024/04/14 00:41
Last patch testing requests (2)
Created Duration User Patch Repo Result
2024/05/21 22:21 24m retest repro upstream OK log
2024/05/06 09:04 21m david@redhat.com git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-hotfixes-unstable OK log

Sample crash report:
------------[ cut here ]------------
WARNING: CPU: 1 PID: 5288 at arch/x86/include/asm/pgtable.h:403 pte_uffd_wp arch/x86/include/asm/pgtable.h:403 [inline]
WARNING: CPU: 1 PID: 5288 at arch/x86/include/asm/pgtable.h:403 hpage_collapse_scan_pmd+0xd32/0x14c0 mm/khugepaged.c:1316
Modules linked in:
CPU: 1 PID: 5288 Comm: syz-executor.4 Not tainted 6.9.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
RIP: 0010:pte_uffd_wp arch/x86/include/asm/pgtable.h:403 [inline]
RIP: 0010:hpage_collapse_scan_pmd+0xd32/0x14c0 mm/khugepaged.c:1316
Code: 90 90 e9 4b f6 ff ff 4c 8b 64 24 48 e8 f7 ee 9e ff 31 ff 4c 89 ee e8 fd e9 9e ff 4d 85 ed 0f 84 b5 01 00 00 e8 df ee 9e ff 90 <0f> 0b 90 41 be 09 00 00 00 0f b6 6c 24 47 48 8b 5c 24 10 e9 fb fa
RSP: 0018:ffffc90003abf9b0 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffff88807a402000 RCX: ffffffff81eed643
RDX: ffff888021ddbc00 RSI: ffffffff81eed651 RDI: 0000000000000007
RBP: 000000006897fc67 R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000002 R12: 0000000020800000
R13: 0000000000000002 R14: 0000000000000400 R15: ffff88801e4dcc00
FS:  00007fd661dde6c0(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7e57ed9ba1 CR3: 0000000025328000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 madvise_collapse+0x738/0xb10 mm/khugepaged.c:2761
 madvise_vma_behavior+0x202/0x1b20 mm/madvise.c:1074
 madvise_walk_vmas+0x1cf/0x2c0 mm/madvise.c:1248
 do_madvise+0x309/0x640 mm/madvise.c:1428
 __do_sys_madvise mm/madvise.c:1441 [inline]
 __se_sys_madvise mm/madvise.c:1439 [inline]
 __x64_sys_madvise+0xa9/0x110 mm/madvise.c:1439
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd66227dea9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fd661dde0c8 EFLAGS: 00000246 ORIG_RAX: 000000000000001c
RAX: ffffffffffffffda RBX: 00007fd6623ac050 RCX: 00007fd66227dea9
RDX: 0000000000000019 RSI: 00000000dfc3efff RDI: 00000000203c1000
RBP: 00007fd6622ca4a4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007fd6623ac050 R15: 00007ffd98c8dfa8
 </TASK>

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/04/29 15:20 upstream e67572cd2204 27e33c58 .config strace log report syz [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in hpage_collapse_scan_pmd
2024/04/29 13:38 upstream e67572cd2204 27e33c58 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in hpage_collapse_scan_pmd
2024/05/07 19:00 upstream dccb07f2914c cb2dcc0e .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in hpage_collapse_scan_pmd
* Struck through repros no longer work on HEAD.