Re: [syzbot] [mm?] WARNING in unmap_page_range (3)

[David Hildenbrand]

On 19.03.24 11:43, syzbot wrote:
> Hello,
>
> syzbot found the following issue on:
>
> HEAD commit:    e5eb28f6d1af Merge tag 'mm-nonmm-stable-2024-03-14-09-36' ..
> git tree:       upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=1383c6c9180000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=4ffb854606e658d
> dashboard link: https://syzkaller.appspot.com/bug?extid=e145145f0c83d4deb8fa
> compiler:       gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=14583abe180000
> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=14298231180000
>
> Downloadable assets:
> disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7bc7510fe41f/non_bootable_disk-e5eb28f6.raw.xz
> vmlinux: https://storage.googleapis.com/syzbot-assets/a5c7ad05d6b2/vmlinux-e5eb28f6.xz
> kernel image: https://storage.googleapis.com/syzbot-assets/531cb1917612/bzImage-e5eb28f6.xz
>
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+e145145f0c83d4deb8fa@xxxxxxxxxxxxxxxxxxxxxxxxx
>
> WARNING: CPU: 2 PID: 5169 at mm/memory.c:1539 zap_present_ptes mm/memory.c:1539 [inline]
> WARNING: CPU: 2 PID: 5169 at mm/memory.c:1539 zap_pte_range mm/memory.c:1603 [inline]
> WARNING: CPU: 2 PID: 5169 at mm/memory.c:1539 zap_pmd_range mm/memory.c:1720 [inline]
> WARNING: CPU: 2 PID: 5169 at mm/memory.c:1539 zap_pud_range mm/memory.c:1749 [inline]
> WARNING: CPU: 2 PID: 5169 at mm/memory.c:1539 zap_p4d_range mm/memory.c:1770 [inline]
> WARNING: CPU: 2 PID: 5169 at mm/memory.c:1539 unmap_page_range+0x2a54/0x3bf0 mm/memory.c:1791

Fix is already on its way upstream:

https://lkml.kernel.org/r/20240313213107.235067-1-peterx@xxxxxxxxxx

Should shortly appear at mm-hotfixes-unstable.

#syz fix: mm/memory: Fix missing pte marker for !page on pte zaps

--
Cheers,

David / dhildenb