Re: [syzbot] [trace?] WARNING in tracing_buffers_mmap_close (2)

From: Hillf Danton

Date: Tue Nov 11 2025 - 18:27:44 EST


> Date: Tue, 11 Nov 2025 09:05:31 -0800
> Hello,
>
> syzbot found the following issue on:
>
> HEAD commit: 4a0c9b339199 Merge tag 'probes-fixes-v6.18-rc4' of git://g..
> git tree: upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=127c3bcd980000
> kernel config: https://syzkaller.appspot.com/x/.config?x=19d831c6d0386a9c
> dashboard link: https://syzkaller.appspot.com/bug?extid=a72c325b042aae6403c7
> compiler: gcc (Debian 12.2.0-14+deb12u1) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=13fb5342580000
> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=167c3bcd980000

#syz test

--- x/mm/mmap_lock.c
+++ y/mm/mmap_lock.c
@@ -240,6 +240,7 @@ retry:
/* Check if the VMA got isolated after we found it */
if (PTR_ERR(vma) == -EAGAIN) {
count_vm_vma_lock_event(VMA_LOCK_MISS);
+ mas_set(&mas, address);
/* The area was replaced with another one */
goto retry;
}
--