From: Dave Hansen <dave.hansen@intel.com>
To: Andrew Cooper <andrew.cooper3@citrix.com>,
LKML <linux-kernel@vger.kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>,
Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
Dave Hansen <dave.hansen@linux.intel.com>,
x86@kernel.org, "H. Peter Anvin" <hpa@zytor.com>,
Peter Zijlstra <peterz@infradead.org>,
Sohil Mehta <sohil.mehta@intel.com>,
Yuntao Wang <yuntao.wang@linux.dev>,
Zhang Rui <rui.zhang@intel.com>
Subject: Re: x86/apic: Drop useless row from the TSC deadline errata table
Date: Tue, 6 Jan 2026 07:16:40 -0800 [thread overview]
Message-ID: <68eb4ee9-4851-4e87-ae1f-e527597b8c5b@intel.com> (raw)
In-Reply-To: <20250716160824.2167709-1-andrew.cooper3@citrix.com>
On 7/16/25 09:08, Andrew Cooper wrote:
> A microcode revision of 0 is guaranteed to exit
> apic_validate_deadline_timer() early, but a better way is with no
> row at all.
>
> No functional change.
There's one bit of background that is missing which is that the
steppings are unaffected by the erratum. How about this for a changelog?
The later INTEL_SKYLAKE_X steppings (0x5=>0xf, aka. CXL/CPX) are
unaffected by the TSC deadline erratum. There is an entry in the
deadline_match[] table to reflect this. It puts puts a '0' in the table
to represent that all microcode versions >=0 are unaffected by the erratum.
That entry is unnecessary. The best way to indicate that a CPU is
unaffected is to simply omit it from the table.
Remove the stepping >=0x5 entry from the table.
next prev parent reply other threads:[~2026-01-06 15:16 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-07-16 16:08 x86/apic: Drop useless CXL/CPX row from the TSC deadline errata table Andrew Cooper
2025-07-17 20:25 ` Sohil Mehta
2025-07-18 10:43 ` Andrew Cooper
2025-07-18 19:25 ` Sohil Mehta
2026-01-06 15:16 ` Dave Hansen [this message]
2026-01-06 18:14 ` [PATCH v2] " Andrew Cooper
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=68eb4ee9-4851-4e87-ae1f-e527597b8c5b@intel.com \
--to=dave.hansen@intel.com \
--cc=andrew.cooper3@citrix.com \
--cc=bp@alien8.de \
--cc=dave.hansen@linux.intel.com \
--cc=hpa@zytor.com \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@redhat.com \
--cc=peterz@infradead.org \
--cc=rui.zhang@intel.com \
--cc=sohil.mehta@intel.com \
--cc=tglx@linutronix.de \
--cc=x86@kernel.org \
--cc=yuntao.wang@linux.dev \
/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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.