linux-kernel - Re: [PATCH v5] x86/cpu/intel: Fix the constant

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <f8f1faa6-d35d-439f-b5c3-2c20f2e2bb8d@intel.com>
Date: Wed, 6 Aug 2025 16:31:54 -0700
From: Sohil Mehta <sohil.mehta@...el.com>
To: Suchit Karunakaran <suchitkarunakaran@...il.com>, <tglx@...utronix.de>,
	<mingo@...hat.com>, <bp@...en8.de>, <dave.hansen@...ux.intel.com>,
	<hpa@...or.com>, <darwi@...utronix.de>, <peterz@...radead.org>,
	<ravi.bangoria@....com>
CC: <skhan@...uxfoundation.org>, <linux-kernel-mentees@...ts.linux.dev>,
	<linux-kernel@...r.kernel.org>, <stable@...r.kernel.org>
Subject: Re: [PATCH v5] x86/cpu/intel: Fix the constant_tsc model check for
 Pentium 4

On 8/6/2025 8:34 AM, Suchit Karunakaran wrote:
> Pentium 4's which are INTEL_P4_PRESCOTT (model 0x03) and later have
> a constant TSC. This was correctly captured until commit fadb6f569b10
> ("x86/cpu/intel: Limit the non-architectural constant_tsc model checks").
> 
> In that commit, an error was introduced while selecting the last P4
> model (0x06) as the upper bound. Model 0x06 was transposed to
> INTEL_P4_WILLAMETTE, which is just plain wrong. That was presumably a
> simple typo, probably just copying and pasting the wrong P4 model.
> 
> Fix the constant TSC logic to cover all later P4 models. End at
> INTEL_P4_CEDARMILL which accurately corresponds to the last P4 model.
> 
> Fixes: fadb6f569b10 ("x86/cpu/intel: Limit the non-architectural constant_tsc model checks")
> Cc: <stable@...r.kernel.org> # v6.15
> Signed-off-by: Suchit Karunakaran <suchitkarunakaran@...il.com>
> ---


Reviewed-by: Sohil Mehta <sohil.mehta@...el.com>