Date:   Mon, 20 Feb 2023 18:46:04 +0100
From:   Borislav Petkov <bp@alien8.de>
To:     Josh Poimboeuf <jpoimboe@kernel.org>
Cc:     KP Singh <kpsingh@kernel.org>, linux-kernel@vger.kernel.org,
        pjt@google.com, evn@google.com, tglx@linutronix.de,
        mingo@redhat.com, dave.hansen@linux.intel.com, x86@kernel.org,
        hpa@zytor.com, peterz@infradead.org,
        pawan.kumar.gupta@linux.intel.com, kim.phillips@amd.com,
        alexandre.chartre@oracle.com, daniel.sneddon@linux.intel.com,
        =?utf-8?B?Sm9zw6k=?= Oliveira <joseloliveira11@gmail.com>,
        Rodrigo Branco <rodrigo@kernelhacking.com>,
        Alexandra Sandulescu <aesa@google.com>,
        Jim Mattson <jmattson@google.com>, stable@vger.kernel.org
Subject: Re: [PATCH RESEND] x86/speculation: Fix user-mode spectre-v2
 protection with KERNEL_IBRS
Message-ID: <Y/Ox3MJZF1Yb7b6y@zn.tnic>
References: <20230220120127.1975241-1-kpsingh@kernel.org>
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On Mon, Feb 20, 2023 at 08:34:42AM -0800, Josh Poimboeuf wrote:
> We will never enable IBRS in user space.  We tried that years ago and it
> was very slow.

Then I don't know what this is trying to fix.

We'd need a proper bug statement in the commit message what the problem
is. As folks have established, the hw vuln mess is a whole universe of
crazy. So without proper documenting, this spaghetti madness will be
completely unreadable.

Thx.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette