linux-kernel - Re: [PATCH] x86/cpufeatures: SGX: Adjust the error message when BIOS does not support SGX

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: <ZqkpSX8xfbny7L0e@google.com>
Date: Tue, 30 Jul 2024 10:56:25 -0700
From: Sean Christopherson <seanjc@...gle.com>
To: Kai Huang <kai.huang@...el.com>
Cc: "bp@...en8.de" <bp@...en8.de>, 
	"dave.hansen@...ux.intel.com" <dave.hansen@...ux.intel.com>, "hpa@...or.com" <hpa@...or.com>, 
	"wangyuli@...ontech.com" <wangyuli@...ontech.com>, "tglx@...utronix.de" <tglx@...utronix.de>, 
	"mingo@...hat.com" <mingo@...hat.com>, "xiangzelong@...ontech.com" <xiangzelong@...ontech.com>, 
	"baimingcong@...ontech.com" <baimingcong@...ontech.com>, 
	"linux-sgx@...r.kernel.org" <linux-sgx@...r.kernel.org>, "jarkko@...nel.org" <jarkko@...nel.org>, 
	"x86@...nel.org" <x86@...nel.org>, "guanwentao@...ontech.com" <guanwentao@...ontech.com>, 
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>, 
	"haitao.huang@...ux.intel.com" <haitao.huang@...ux.intel.com>, "wubo@...ontech.com" <wubo@...ontech.com>
Subject: Re: [PATCH] x86/cpufeatures: SGX: Adjust the error message when BIOS
 does not support SGX

On Tue, Jul 30, 2024, Kai Huang wrote:
> On Tue, 2024-07-30 at 10:49 +0800, WangYuli wrote:
> > When SGX is not supported by the BIOS, we still output the error
> > 'SGX disabled by BIOS', which can be confusing since there might not be
> > an SGX-related option in the BIOS settings.
> 
> +linux-sgx list, Jarkko, Haitao.
> 
> This message is only printed when SGX is reported in CPUID but is not
> enabled in the FEAT_CTL MSR.  I can only recall this can happen when the
> BIOS actually provides an option for the user to turn on/off SGX, in
> which case the current message is correct.

FWIW, this could easily happen with a virtual machine, e.g. running an old QEMU
with `-cpu host`.