From: Dave Hansen <dave.hansen@intel.com>
To: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Steve Wahl <steve.wahl@hpe.com>,
Dave Hansen <dave.hansen@linux.intel.com>,
Andy Lutomirski <luto@kernel.org>,
Peter Zijlstra <peterz@infradead.org>,
Thomas Gleixner <tglx@linutronix.de>,
Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
x86@kernel.org, "H. Peter Anvin" <hpa@zytor.com>,
linux-kernel@vger.kernel.org,
Linux regressions mailing list <regressions@lists.linux.dev>,
Pavin Joseph <me@pavinjoseph.com>,
stable@vger.kernel.org, Eric Hagberg <ehagberg@gmail.com>,
Simon Horman <horms@verge.net.au>, Dave Young <dyoung@redhat.com>,
Sarah Brofeldt <srhb@dbc.dk>, Russ Anderson <rja@hpe.com>,
Dimitri Sivanich <sivanich@hpe.com>
Subject: Re: [PATCH] x86/mm/ident_map: Use full gbpages in identity maps except on UV platform.
Date: Fri, 22 Mar 2024 10:40:37 -0700 [thread overview]
Message-ID: <2f8d726a-9800-4068-9c0c-6c4a79d69a85@intel.com> (raw)
In-Reply-To: <87le6ab2bn.fsf@email.froward.int.ebiederm.org>
On 3/22/24 10:31, Eric W. Biederman wrote:
>> I'd much rather add synthetic entries to the memory maps that have this
>> information than hack around it by assuming that things are within a
>> gigabyte.
> So this change is a partial revert of a change that broke kexec in
> existing configurations. To fix a regression that breaks kexec.
Let's back up for a second:
* Mapping extra memory on UV systems causes halts[1]
* Mapping extra memory on UV systems breaks kexec (this thread)
So we're in a pickle. I understand your concern for kexec. But I'm
concerned that fixing the kexec problem will re-expose us to the [1]
problem.
Steve, can you explain a bit why this patch doesn't re-expose the kernel
to the [1] bug?
1. https://lore.kernel.org/all/20240126164841.170866-1-steve.wahl@hpe.com/
next prev parent reply other threads:[~2024-03-22 17:40 UTC|newest]
Thread overview: 28+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-03-22 16:21 Steve Wahl
2024-03-22 16:27 ` Dave Hansen
2024-03-22 17:31 ` Eric W. Biederman
2024-03-22 17:40 ` Dave Hansen [this message]
2024-03-22 17:43 ` Dave Hansen
2024-03-22 18:06 ` Steve Wahl
2024-03-22 18:05 ` Steve Wahl
2024-03-22 23:29 ` Dave Hansen
2024-03-24 4:45 ` Eric W. Biederman
2024-03-24 18:16 ` Dave Hansen
2024-03-25 19:15 ` Steve Wahl
2024-03-24 10:31 ` Ingo Molnar
2024-03-25 2:03 ` Russ Anderson
2024-03-25 10:58 ` Ingo Molnar
2024-04-05 13:13 ` Eric Hagberg
2024-04-05 13:35 ` Greg KH
2024-03-25 15:04 ` Eric W. Biederman
2024-03-25 19:41 ` Steve Wahl
2024-03-27 12:57 ` Eric W. Biederman
2024-03-27 15:33 ` Steve Wahl
2024-03-28 5:05 ` Eric W. Biederman
2024-03-28 15:38 ` Steve Wahl
2024-03-31 3:46 ` Eric W. Biederman
2024-04-01 15:15 ` Steve Wahl
2024-04-01 18:03 ` Dave Hansen
2024-04-01 18:49 ` Steve Wahl
2024-04-04 19:56 ` Steve Wahl
2024-03-25 19:22 ` Steve Wahl
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=2f8d726a-9800-4068-9c0c-6c4a79d69a85@intel.com \
--to=dave.hansen@intel.com \
--cc=bp@alien8.de \
--cc=dave.hansen@linux.intel.com \
--cc=dyoung@redhat.com \
--cc=ebiederm@xmission.com \
--cc=ehagberg@gmail.com \
--cc=horms@verge.net.au \
--cc=hpa@zytor.com \
--cc=linux-kernel@vger.kernel.org \
--cc=luto@kernel.org \
--cc=me@pavinjoseph.com \
--cc=mingo@redhat.com \
--cc=peterz@infradead.org \
--cc=regressions@lists.linux.dev \
--cc=rja@hpe.com \
--cc=sivanich@hpe.com \
--cc=srhb@dbc.dk \
--cc=stable@vger.kernel.org \
--cc=steve.wahl@hpe.com \
--cc=tglx@linutronix.de \
--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
all inboxes | Powered by JetHome®