linux-kernel - Re: [PATCH RFC v2a 5/9] x86/cpufeatures: Add X86_FEATURE

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

Message-ID: <10032664-c16e-4599-ae10-3d2b1aef0265@intel.com>
Date: Mon, 14 Apr 2025 10:45:43 -0700
From: Sohil Mehta <sohil.mehta@...el.com>
To: Dave Hansen <dave.hansen@...el.com>, Ingo Molnar <mingo@...nel.org>,
	"Chang S. Bae" <chang.seok.bae@...el.com>
CC: <linux-kernel@...r.kernel.org>, <x86@...nel.org>, <tglx@...utronix.de>,
	<mingo@...hat.com>, <bp@...en8.de>, <dave.hansen@...ux.intel.com>
Subject: Re: [PATCH RFC v2a 5/9] x86/cpufeatures: Add X86_FEATURE_APX

On 4/14/2025 10:32 AM, Dave Hansen wrote:
> On 4/14/25 10:28, Sohil Mehta wrote:
>> Functionally, the only change I have requested is in patch 7/9 to add a
>> "disabling XSAVE" message to the error print.
> 
> That's probably a good idea to stick in:
> 
> 	fpu__init_disable_system_xstate()
> 
> for all of the "out_disable" cases to use, no?

That way my initial inclination as well. My suggestion was mainly to
keep it consistent. But looking more closely, there is mismatch already.
So either of the options work for me.

"x86/fpu: FP/SSE not present amongst the CPU's xstate features: 0x%llx."

"x86/fpu: init_fpstate buffer too small (%zu < %d), disabling XSAVE"

"x86/fpu: xfeatures modified from 0x%016llx to 0x%016llx during init,
disabling XSAVE"