linux-kernel - Re: [PATCH v10 09/15] x86/traps: Consolidate user fixups in exc_general

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Message-ID: <75df4d00c009c60043b0c3edb8990342d9b9b9b3.camel@intel.com>
Date: Wed, 8 Oct 2025 17:43:43 +0000
From: "Edgecombe, Rick P" <rick.p.edgecombe@...el.com>
To: "Mehta, Sohil" <sohil.mehta@...el.com>, "tglx@...utronix.de"
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Subject: Re: [PATCH v10 09/15] x86/traps: Consolidate user fixups in
 exc_general_protection()

On Tue, 2025-10-07 at 15:41 -0700, Sohil Mehta wrote:
> On 10/7/2025 10:46 AM, Edgecombe, Rick P wrote:
> > On Mon, 2025-10-06 at 23:51 -0700, Sohil Mehta wrote:
> > > Move the UMIP exception fixup along with the other user mode fixups,
> > > that is, under the common "if (user_mode(regs))" condition where the
> > > rest of the fixups reside.
> > 
> > Can you mention that it also drops static_cpu_has(X86_FEATURE_UMIP) check
> > because fixup_umip_exception() already checks
> > cpu_feature_enabled(X86_FEATURE_UMIP)?
> > 
> 
> There is no existing check. The current patch moves the X86_FEATURE_UMIP
> check to fixup_umip_exception().

Doh!

> 
> I can add a sentence to say that the current check is split into two
> separate locations. But, is it not obvious from the diff?

The log is pretty thin, I'd add it.