linux-kernel - Re: Objtool segfault inside an VM, based on commit 24172e0d7990

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20251117175041.GA703155@ax162>
Date: Mon, 17 Nov 2025 10:50:41 -0700
From: Nathan Chancellor <nathan@...nel.org>
To: Qu Wenruo <quwenruo.btrfs@....com>
Cc: LKML <linux-kernel@...r.kernel.org>,
	linux-btrfs <linux-btrfs@...r.kernel.org>
Subject: Re: Objtool segfault inside an VM, based on commit 24172e0d7990

On Mon, Nov 17, 2025 at 03:40:35PM +1030, Qu Wenruo wrote:
> 
> 
> 在 2025/11/17 13:33, Qu Wenruo 写道:
> > 
> > 
> > 在 2025/11/17 13:10, Qu Wenruo 写道:
> > > Hi,
> > > 
> > > Recently I'm hitting pretty frequent objtool crashes, sometimes
> > > during module linking (btrfs in my case) sometimes during the
> > > vmlinux linking.
> > > 
> > > Unfortunately I don't have a coredump for it.
> > > 
> > > The only info so far is from dmesg (and obvious the compile failure):
> > > 
> > > [  625.066787] traps: objtool[46220] general protection fault
> > > ip:563ab54c6eb0 sp:7ffd9c2ba7c8 error:0 in
> > > objtool[19eb0,563ab54b2000+1f000]
> > > 
> > > The involved VM has the following spec:
> > > 
> > > - Kernel branch
> > >    Btrfs' development branch.
> > > 
> > >    The base commit is 24172e0d79900908cf5ebf366600616d29c9b417, around
> > >    v6.18-rc6.
> 
> Furthermore, if just compiling on old kernels (in my case, 6.17.8), I
> haven't yet hit a linking time segfault.
> 
> So it's something in the v6.18 release cycle.
> 
> Not sure if it's the recent Zen5 related hassles.

I had similar objtool crashes and David's fix [1] from another bug
report thread [2] appears to resolve this for me.

[1]: https://github.com/davidhildenbrand/linux/commit/58e62699f77738188730d489accd01ad8e3cdeeb
[2]: https://lore.kernel.org/20251117082023.90176-1-00107082@163.com/

Cheers,
Nathan