linux-kernel - Re: [PATCH RFC v2 8/9] x86/fpu/apx: Enable APX state support

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: <bec4acd1-8a97-43e2-9119-f0874d2f3ccf@intel.com>
Date: Mon, 14 Apr 2025 08:41:18 -0700
From: Sohil Mehta <sohil.mehta@...el.com>
To: "Chang S. Bae" <chang.seok.bae@...el.com>, <linux-kernel@...r.kernel.org>
CC: <x86@...nel.org>, <tglx@...utronix.de>, <mingo@...hat.com>,
	<bp@...en8.de>, <dave.hansen@...ux.intel.com>
Subject: Re: [PATCH RFC v2 8/9] x86/fpu/apx: Enable APX state support

On 3/20/2025 4:42 PM, Chang S. Bae wrote:
> With securing APX against conflicting MPX, it is now ready to be enabled.
> Include APX in the enabled xfeature set.
> 
> Signed-off-by: Chang S. Bae <chang.seok.bae@...el.com>
> ---
>  arch/x86/include/asm/fpu/xstate.h | 3 ++-
>  arch/x86/kernel/fpu/xstate.c      | 3 ++-
>  2 files changed, 4 insertions(+), 2 deletions(-)
> 

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

> diff --git a/arch/x86/include/asm/fpu/xstate.h b/arch/x86/include/asm/fpu/xstate.h
> index 7f39fe7980c5..b308a76afbb7 100644
> --- a/arch/x86/include/asm/fpu/xstate.h
> +++ b/arch/x86/include/asm/fpu/xstate.h
> @@ -32,7 +32,8 @@
>  				      XFEATURE_MASK_PKRU | \
>  				      XFEATURE_MASK_BNDREGS | \
>  				      XFEATURE_MASK_BNDCSR | \
> -				      XFEATURE_MASK_XTILE)
> +				      XFEATURE_MASK_XTILE | \
> +				      XFEATURE_MASK_APX)
>  
>  /*
>   * Features which are restored when returning to user space.
> diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c
> index 0d68d5c4bc48..a5e3954dc834 100644
> --- a/arch/x86/kernel/fpu/xstate.c
> +++ b/arch/x86/kernel/fpu/xstate.c
> @@ -371,7 +371,8 @@ static __init void os_xrstor_booting(struct xregs_state *xstate)
>  	 XFEATURE_MASK_BNDCSR |			\
>  	 XFEATURE_MASK_PASID |			\
>  	 XFEATURE_MASK_CET_USER |		\
> -	 XFEATURE_MASK_XTILE)
> +	 XFEATURE_MASK_XTILE |			\
> +	 XFEATURE_MASK_APX)
>  
>  /*
>   * setup the xstate image representing the init state