Re: [syzbot] [kernel?] possible deadlock in binder_alloc_free_page

[Carlos Llamas <cmllamas@google.com>]

On Sat, Jan 11, 2025 at 02:30:22AM -0800, syzbot wrote:
> Hello,
> 
> syzbot found the following issue on:
> 
> HEAD commit:    7b4b9bf203da Add linux-next specific files for 20250107
> git tree:       linux-next
> console output: https://syzkaller.appspot.com/x/log.txt?x=17d02dc4580000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=63fa2c9d5e12faef
> dashboard link: https://syzkaller.appspot.com/bug?extid=799a2d4576c454ac2693
> compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=10302dc4580000
> 
> Downloadable assets:
> disk image: https://storage.googleapis.com/syzbot-assets/c179cc0c7a3c/disk-7b4b9bf2.raw.xz
> vmlinux: https://storage.googleapis.com/syzbot-assets/fdea80f2ec16/vmlinux-7b4b9bf2.xz
> kernel image: https://storage.googleapis.com/syzbot-assets/a277fcaff608/bzImage-7b4b9bf2.xz
> 
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+799a2d4576c454ac2693@syzkaller.appspotmail.com

Hey Suren, just FYI. I bisected this to commit e8f32ff00a66 ("mm:
replace vm_lock and detached flag with a reference count"), which was an
older version (v7) of your patchset. However, I've tested the same on
the newer linux-next tip with your v10 and it no longer reproduces the
problem.

Nothing else for me to do here.

Regards,
Carlos Llamas