linux-kernel - Re: [PATCH v3] x86/bugs: Add a separate config for each mitigation

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: <a5fbcf09-2445-28f1-4113-0de4f72b7f90@intel.com>
Date:   Thu, 28 Sep 2023 06:40:18 -0700
From:   Dave Hansen <dave.hansen@...el.com>
To:     Breno Leitao <leitao@...ian.org>,
        Thomas Gleixner <tglx@...utronix.de>,
        Ingo Molnar <mingo@...hat.com>, Borislav Petkov <bp@...en8.de>,
        Dave Hansen <dave.hansen@...ux.intel.com>, x86@...nel.org,
        "H. Peter Anvin" <hpa@...or.com>,
        Peter Zijlstra <peterz@...radead.org>,
        Josh Poimboeuf <jpoimboe@...nel.org>,
        Pawan Gupta <pawan.kumar.gupta@...ux.intel.com>
Cc:     leit@...a.com,
        "open list:X86 ARCHITECTURE (32-BIT AND 64-BIT)" 
        <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH v3] x86/bugs: Add a separate config for each mitigation

On 9/28/23 05:45, Breno Leitao wrote:
> 1) Create one Kconfig entry per mitigation, so, the user can pick and
> choose what to enable and disable. (Version 3 of this patch. May need a
> re-spin due to the new mitigations being added.)

This means, what, roughly 18 today?

#define X86_BUG_CPU_MELTDOWN		X86_BUG(14)
...
#define X86_BUG_GDS                     X86_BUG(30)

Plus two bonus ones:

#define X86_BUG_SRSO                    X86_BUG(1*32 + 0)
#define X86_BUG_DIV0                    X86_BUG(1*32 + 1)

... and we've slowed down the rate at which we're adding these, but
we're still seeing a couple a year.

Perhaps Pawan and the others actually _doing_ the patches for these can
speak up, but I don't think adding a Kconfig option will be too much
additional work for each new X86_BUG.

I still think it's highly unlikely that someone will come through and
pick and choose among a few dozen vulnerabilities.