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Date:   Wed, 25 Oct 2023 00:28:37 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     "H. Peter Anvin" <hpa@zytor.com>
Cc:     Pawan Gupta <pawan.kumar.gupta@linux.intel.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        Dave Hansen <dave.hansen@linux.intel.com>, x86@kernel.org,
        Josh Poimboeuf <jpoimboe@kernel.org>,
        Andy Lutomirski <luto@kernel.org>,
        Jonathan Corbet <corbet@lwn.net>,
        Sean Christopherson <seanjc@google.com>,
        Paolo Bonzini <pbonzini@redhat.com>, tony.luck@intel.com,
        ak@linux.intel.com, tim.c.chen@linux.intel.com,
        linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org,
        kvm@vger.kernel.org,
        Alyssa Milburn <alyssa.milburn@linux.intel.com>,
        Daniel Sneddon <daniel.sneddon@linux.intel.com>,
        antonio.gomez.iglesias@linux.intel.com,
        Alyssa Milburn <alyssa.milburn@intel.com>, song@kernel.org
Subject: Re: [PATCH  v2 1/6] x86/bugs: Add asm helpers for executing VERW
Message-ID: <20231024222837.GH33965@noisy.programming.kicks-ass.net>
References: <20231024-delay-verw-v2-0-f1881340c807@linux.intel.com>
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On Tue, Oct 24, 2023 at 11:27:36AM -0700, H. Peter Anvin wrote:

> the only overhead to modules other than load time (including the
> runtime linking) is that modules can't realistically be mapped using
> large page entries.

Song is working on that. Currently the module allocator is split between
all (5 IIRC) different page permissions required, next step is using
large page pools for those.