From: Borislav Petkov <bp@alien8.de>
To: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: x86-ml <x86@kernel.org>, lkml <linux-kernel@vger.kernel.org>,
Andy Lutomirski <luto@kernel.org>
Subject: Re: WARNING: kernel stack frame pointer at ffffffff82e03f40 in swapper:0 has bad value (null)
Date: Mon, 12 Dec 2016 22:34:46 +0100 [thread overview]
Message-ID: <20161212213446.imd3hpt3nudomu7r@pd.tnic> (raw)
In-Reply-To: <20161212211627.yuodrw35xwq3hmn7@treble>
On Mon, Dec 12, 2016 at 03:16:27PM -0600, Josh Poimboeuf wrote:
> I still can't figure out what could cause this, nor can I recreate it.
Want my .config?
> Andy, any idea? I'm trying to figure out why a stack trace of the
> initial task, early in start_kernel(), would show start_cpu() on the
> stack *twice*. The start_cpu() entry on the stack at ffffffffbce03f50
> is right where it's supposed to be. But then there's another
> start_cpu() entry at 0xffffffffbce03f48 which is pointed to by the frame
> pointer chain. I can't figure out where that one came from and why the
> stack is offset by a word, compared to all the other idle task stacks
> I've seen.
Btw, why do you have:
call 1f # put return address on stack for unwinder
there in start_cpu() instead of
push $start_cpu
or so? That CALL looks strange there. If you want to put the return
address, just push start_cpu's address and that's it.
Or am I missing something?
> Boris, what kind of CPU is it?
[ 0.169371] smpboot: CPU0: Intel(R) Xeon(R) CPU E5-1620 0 @ 3.60GHz (family: 0x6, model: 0x2d, stepping: 0x7)
Sandybridge. The model 0x2d corresponds to that INTEL_FAM6_SANDYBRIDGE_X
define in intel-family.h.
--
Regards/Gruss,
Boris.
Good mailing practices for 400: avoid top-posting and trim the reply.
next prev parent reply other threads:[~2016-12-12 21:34 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-12-10 16:17 WARNING: kernel stack frame pointer at ffffffff82e03f40 in swapper:0 has bad value (null) Borislav Petkov
2016-12-10 17:04 ` Josh Poimboeuf
2016-12-10 17:28 ` Borislav Petkov
2016-12-12 15:45 ` Josh Poimboeuf
2016-12-12 17:50 ` Borislav Petkov
2016-12-12 18:10 ` Josh Poimboeuf
2016-12-12 21:16 ` Josh Poimboeuf
2016-12-12 21:34 ` Borislav Petkov [this message]
2016-12-12 22:11 ` Josh Poimboeuf
2016-12-12 22:33 ` Borislav Petkov
2016-12-12 23:05 ` Josh Poimboeuf
2016-12-13 14:34 ` Josh Poimboeuf
2016-12-13 16:55 ` Andy Lutomirski
2016-12-13 17:26 ` Josh Poimboeuf
2016-12-13 17:51 ` Borislav Petkov
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=20161212213446.imd3hpt3nudomu7r@pd.tnic \
--to=bp@alien8.de \
--cc=jpoimboe@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=luto@kernel.org \
--cc=x86@kernel.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).