From: Rik van Riel <riel@surriel.com>
To: Tom Lendacky <thomas.lendacky@amd.com>,
linux-kernel@vger.kernel.org, x86@kernel.org
Cc: Thomas Gleixner <tglx@kernel.org>, Ingo Molnar <mingo@redhat.com>,
Borislav Petkov <bp@alien8.de>,
Dave Hansen <dave.hansen@linux.intel.com>,
"H. Peter Anvin" <hpa@zytor.com>,
Andy Lutomirski <luto@kernel.org>,
Peter Zijlstra <peterz@infradead.org>,
Nadav Amit <nadav.amit@gmail.com>,
Dave Hansen <dave.hansen@intel.com>
Subject: Re: [PATCH v2] x86/mm: Disable broadcast TLB flush when PCID is disabled
Date: Tue, 19 May 2026 15:28:49 -0400 [thread overview]
Message-ID: <590444fbdac331e9673e1222a186218d526d779b.camel@surriel.com> (raw)
In-Reply-To: <b792f1ce5d3ca07ad04e3216dfb696c273b570d0.1779218522.git.thomas.lendacky@amd.com>
On Tue, 2026-05-19 at 14:22 -0500, Tom Lendacky wrote:
>
> All processors that support broadcast TLB invalidation also have PCID
> support, so it is only the "nopcid" scenario that is of concern. In
> this situation just disable the broadcast TLB support using the CPUID
> dependency support by making X86_FEATURE_INVLPGB dependent on
> X86_FEATURE_PCID.
>
> Fixes: 4afeb0ed1753 ("x86/mm: Enable broadcast TLB invalidation for
> multi-threaded processes")
> Assisted-by: Claude:claude-opus-4.7
> Suggested-by: Dave Hansen <dave.hansen@intel.com>
> Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Acked-by: Rik van Riel <riel@surriel.com>
--
All Rights Reversed.
next prev parent reply other threads:[~2026-05-19 19:29 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-05-19 19:22 Tom Lendacky
2026-05-19 19:28 ` Rik van Riel [this message]
2026-05-19 19:49 ` Dave Hansen
2026-05-19 21:21 ` Tom Lendacky
2026-05-19 21:47 ` Dave Hansen
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