linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Arvind Sankar <nivedita@alum.mit.edu>
To: Ingo Molnar <mingo@kernel.org>
Cc: linux-kernel@vger.kernel.org,
	Randy Dunlap <rdunlap@infradead.org>,
	Andreas Smas <andreas@lonelycoder.com>
Subject: Re: x86/purgatory: undefined symbol __stack_chk_fail
Date: Sat, 28 Sep 2019 17:14:55 -0400	[thread overview]
Message-ID: <20190928211453.GA2300554@rani.riverdale.lan> (raw)

On Sat, Sep 28, 2019 at 12:41:29PM +0000, Ingo Molnar wrote:
> 
> * Randy Dunlap <rdunlap@infradead.org> wrote:
> 
> > On 9/3/19 8:50 AM, Andreas Smas wrote:
> > > Hi,
> > > 
> > > For me, kernels built including this commit
> > > b059f801a937 (x86/purgatory: Use CFLAGS_REMOVE rather than reset KBUILD_CFLAGS)
> > > 
> > > results in kexec() failing to load the kernel:
> > > 
> > > kexec: Undefined symbol: __stack_chk_fail
> > > kexec-bzImage64: Loading purgatory failed
> > > 
> > > Can be seen:
> > > 
> > > $ readelf -a arch/x86/purgatory/purgatory.ro | grep UND
> > >      0: 0000000000000000     0 NOTYPE  LOCAL  DEFAULT  UND
> > >     51: 0000000000000000     0 NOTYPE  GLOBAL DEFAULT  UND __stack_chk_fail
> > > 
> > > Using: gcc version 7.4.0 (Ubuntu 7.4.0-1ubuntu1~18.04.1)
> > > 
> > > Adding -ffreestanding or -fno-stack-protector to ccflags-y in
> > > arch/x86/purgatory/Makefile
> > > fixes the problem. Not sure which would be preferred.
> > > 
> > 
> > Hi,
> > Do you have a kernel .config file that causes this?
> > I can't seem to reproduce it.
> 
> Does it go away with this fix in x86/urgent:
> 
>   ca14c996afe7: ("x86/purgatory: Disable the stackleak GCC plugin for the purgatory")
> 
>   git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git x86/urgent
> 
> ?
> 
> Thanks,
> 
> 	Ing
This one was fixed by [1] e16c2983fba0f ("x86/purgatory: Change compiler
flags from -mcmodel=kernel to -mcmodel=large to fix kexec relocation
errors") from Steve Wahl, which in addition to changing mcmodel also
added back -ffreestanding (and -fno-zero-initialized-in-bss). It was
merged on the 12th. The stackleak one is a different undefined symbol
error.

[1] https://marc.info/?l=git-commits-head&m=156829711224800

             reply	other threads:[~2019-09-28 21:15 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-09-28 21:14 Arvind Sankar [this message]
2019-09-29 12:12 ` x86/purgatory: undefined symbol __stack_chk_fail Ingo Molnar
  -- strict thread matches above, loose matches on Subject: below --
2019-09-03 15:50 Andreas Smas
2019-09-28  0:48 ` Randy Dunlap
2019-09-28 12:41   ` Ingo Molnar
2019-09-28 17:17 ` Rasmus Villemoes

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20190928211453.GA2300554@rani.riverdale.lan \
    --to=nivedita@alum.mit.edu \
    --cc=andreas@lonelycoder.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@kernel.org \
    --cc=rdunlap@infradead.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).