From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f201.google.com (mail-pl1-f201.google.com [209.85.214.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3ACD328FFFC for ; Thu, 10 Apr 2025 20:39:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744317571; cv=none; b=XK+cZJxw1k0sPQuK8YQ648CYltO9Wcy7sMiynOp3USreRzvBA/DFXdUxXIGnmUhXjrH7iUWgh1MJdsVT60oZZ0PsJAGZpdQz2XJSZ3G8lDVAm6nFhnslP/bwL280RngQ6iAppVuJO0CPyN78C9DWFH4kTa7YTsuAzl8TS6wNRoc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744317571; c=relaxed/simple; bh=+/Da14Q8O99O8gD5GOsB3AbvKUabJM3yMtDdDBWWncs=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=C7is4zNMeUVMe/AgRKyGPHphmejKjdwPjy2dIypWYeUodXNnctEI+3FS1ZUlLDqzuIkV3M3ZEzhaPL00fZ14sxRROmRu0mrnwph39Cx5Y+fh6eJNXMriZsPg5DGdnVbTpdlgJRv9czv+PqTm/2Che+lFoJYEGdmPexjYXStiZ54= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=Ocw97+Ha; arc=none smtp.client-ip=209.85.214.201 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="Ocw97+Ha" Received: by mail-pl1-f201.google.com with SMTP id d9443c01a7336-229668c8659so9766655ad.3 for ; Thu, 10 Apr 2025 13:39:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1744317569; x=1744922369; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=5re5XUGW9IF95wVSy2NMQsySIZSn9P1138cF5o6XU38=; b=Ocw97+HaMov/ANgXnKfvCJQg9Ax6f7nZj881fQP4+4/vpEUgpQLYjohS9TNoqosflX g1DFF97ab1q+oYWle+AvRoLfhr5xjEyhV7+TvUL0j0CNIHJty3RhoxrNi+nsNxisUFeH MX64yz7WyUVBoQ090wqCF2HARl98qNU1aRx+QqqH4GLBnB6+pGYw6b33QPZNEqraXFnm 98V+7eQRYpLC51DoWOW+eGYlOJRtitfO6EJku6/VDYpFeRCQkTvMR0Km7qKPHf4Cp7VN 7YWirSA6aNhY/JCq2VS9yTml51VbCo8iy9+iQ7P32beMxUYnKXHO0VmrWzmQ7dD6n02P n81Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1744317569; x=1744922369; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=5re5XUGW9IF95wVSy2NMQsySIZSn9P1138cF5o6XU38=; b=m5hy4qgrcfsPMsqh9BvwBsmcjjlQcSPuDqYn5mdIQX3xEmlqNG6eJinhe+jxs7/c0u f8bn6HPhhzd4wmOMdnN8F7mV0RAy/VnkzHMURJyC68f1WS/xQ+MQs//t0Cq2nv7iV5/P 4l+9/8t7U2PGMRFwwSDI8XEek1GRgSd2AhJBTS9JKX0aZRKuaBNcnQVBz1RwNBbv2rnN gN0sJDI/jYpEBw50MnAIC3WwH28ATwtlqVSE9TrpGQHDrAxaGyZHjvsLn9CjB/yrxrJm E//mzr7Je0bx46Ay7/M4FlXAmE/IDVQOEws+Pf/40w3jcBJgepfKhUouEeSuL6d1wKfj T0Vw== X-Forwarded-Encrypted: i=1; AJvYcCUQxU9Z/H3matRFNy8TUpmWx7iFiEQde8mxmymBqBa359OVoQ5MXAXsRfwrRA3NvEQAvDGxGXRAmAUzFcA=@vger.kernel.org X-Gm-Message-State: AOJu0YzVjhiDZgMb+ige7JBjQJwFif4738JXj6O2vPT85yz6YW70AdF5 uPW/jJq92FmBgWQhchHurFzi0Tu8x2CosLHUMFz/Yk3+McIyZ2NCioTDz8U1PlnP4Q66JwUr1Gx GUw== X-Google-Smtp-Source: AGHT+IEzT83HzgjEOFZbsaMCZV5hBRnM3M3IalG5XVGaEH7NXrikjfnOtjVPlPzcWgW0Lywqicmh7WKqSSM= X-Received: from plblc7.prod.google.com ([2002:a17:902:fa87:b0:21f:40e5:a651]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a17:903:3c6c:b0:215:b75f:a1cb with SMTP id d9443c01a7336-22bea4a3453mr2764715ad.9.1744317569509; Thu, 10 Apr 2025 13:39:29 -0700 (PDT) Date: Thu, 10 Apr 2025 13:39:28 -0700 In-Reply-To: <20250410-mmio-rename-v1-1-fd4b2e7fc04e@linux.intel.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20250410-mmio-rename-v1-1-fd4b2e7fc04e@linux.intel.com> Message-ID: Subject: Re: [PATCH] x86/bugs/mmio: Rename mmio_stale_data_clear to cpu_buf_vm_clear From: Sean Christopherson To: Pawan Gupta Cc: Josh Poimboeuf , x86@kernel.org, Paolo Bonzini , linux-kernel@vger.kernel.org, kvm@vger.kernel.org Content-Type: text/plain; charset="us-ascii" On Thu, Apr 10, 2025, Pawan Gupta wrote: > The static key mmio_stale_data_clear controls the KVM-only mitigation for > MMIO Stale Data vulnerability. Rename it to reflect its purpose. > > No functional change. > > Signed-off-by: Pawan Gupta > --- > arch/x86/include/asm/nospec-branch.h | 2 +- > arch/x86/kernel/cpu/bugs.c | 16 ++++++++++------ > arch/x86/kvm/vmx/vmx.c | 2 +- > 3 files changed, 12 insertions(+), 8 deletions(-) > > diff --git a/arch/x86/include/asm/nospec-branch.h b/arch/x86/include/asm/nospec-branch.h > index 8a5cc8e70439e10aab4eeb5b0f5e116cf635b43d..c0474e2b741737dad129159adf3b5fc056b6097c 100644 > --- a/arch/x86/include/asm/nospec-branch.h > +++ b/arch/x86/include/asm/nospec-branch.h > @@ -561,7 +561,7 @@ DECLARE_STATIC_KEY_FALSE(mds_idle_clear); > > DECLARE_STATIC_KEY_FALSE(switch_mm_cond_l1d_flush); > > -DECLARE_STATIC_KEY_FALSE(mmio_stale_data_clear); > +DECLARE_STATIC_KEY_FALSE(cpu_buf_vm_clear); Could we tack on "if_mmio" or something? E.g. cpu_buf_vm_clear_if_mmio. FWIW, I don't love that name, so if anyone can come up with something better... I like the idea of tying the static key back to X86_FEATURE_CLEAR_CPU_BUF, but when looking at just the usage in KVM, "cpu_buf_vm_clear" doesn't provide any hints as to when/why KVM needs to clear buffers.