public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Dave Hansen <dave.hansen@intel.com>
To: Kuniyuki Iwashima <kuniyu@amazon.com>,
	x86@kernel.org, linux-edac@vger.kernel.org,
	linux-kernel@vger.kernel.org
Cc: Tony Luck <tony.luck@intel.com>, Borislav Petkov <bp@alien8.de>,
	Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>,
	Dave Hansen <dave.hansen@linux.intel.com>,
	"H. Peter Anvin" <hpa@zytor.com>,
	Benjamin Herrenschmidt <benh@amazon.com>
Subject: Re: WARNING in lmce_supported() during reboot.
Date: Fri, 25 Oct 2024 16:58:47 -0700	[thread overview]
Message-ID: <e1c50570-1b5b-40d2-bab3-05e9ead51a57@intel.com> (raw)
In-Reply-To: <20241025231320.45417-1-kuniyu@amazon.com>

On 10/25/24 16:13, Kuniyuki Iwashima wrote:
> We have seen the splat below few times when just rebooting hosts.
> 
> It rarely happens and seems a timing related, so we don't have a
> reproducer.
> 
> Our kernel source in the splat is here,
> https://github.com/amazonlinux/linux/tree/kernel-6.1.61-85.141.amzn2023

Hi Folks,

We really do need it to be reproduced on mainline.  At the very least,
it would be greatly appreciated if you could summarize what your fork is
doing and why you don't think it is responsible.

But I don't see how this could be timing related.  That MSR gets locked
early from what I can tell, long before the system would be rebooting.

Your best bet is going to be getting a handle on what
MSR_IA32_FEAT_CTL's value was after the CPU was brought up and when this
reboot was attempted.  If those values differ, when it got changed.

I'd _suspect_ some kind of BIOS sleep/wakeup wonkiness where something
forgot to re-lock the MSR.

  parent reply	other threads:[~2024-10-25 23:58 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-10-25 23:13 WARNING in lmce_supported() during reboot Kuniyuki Iwashima
2024-10-25 23:26 ` Benjamin Herrenschmidt
2024-10-25 23:57 ` Luck, Tony
2024-10-25 23:58 ` Dave Hansen [this message]
2024-10-26  2:33   ` Benjamin Herrenschmidt
2024-10-28 15:46     ` Dave Hansen
2024-10-30  2:26     ` Zhuo, Qiuxu

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=e1c50570-1b5b-40d2-bab3-05e9ead51a57@intel.com \
    --to=dave.hansen@intel.com \
    --cc=benh@amazon.com \
    --cc=bp@alien8.de \
    --cc=dave.hansen@linux.intel.com \
    --cc=hpa@zytor.com \
    --cc=kuniyu@amazon.com \
    --cc=linux-edac@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@redhat.com \
    --cc=tglx@linutronix.de \
    --cc=tony.luck@intel.com \
    --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