From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4EEFA32E72A for ; Fri, 14 Nov 2025 15:06:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763132797; cv=none; b=TjRC/DVoUVwV24Xe6WYyaAV8XRQqtB6eCziIYxflWm38Gv+UDnuLrvFWs7gNodGjN38UKgyeb16Hv2507/4r9JL2rf6z7aHQchUl1XtJF+OftjmjdE7RB0I9g0DVp7uP0F8WvU1gD65QHA+IE/OnUkayYWV1jgqRZmeTMwmtTO4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763132797; c=relaxed/simple; bh=HrXid4rFcLKsbwJAAXBJ1FHcFf0N5jAhis38Mj/DeC8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=G572LFSJhwY0EYf/3mSWvgEFOffNUX25ne+WjeYG5LmPJAIy6JF945/wKNIFRMp6QDvHF6/I6yneFmiCSaofBBWhcv1RRAw9RroPszl5rpXBGS7sGY9kHlTDZHbT/NaNU1Y6qcrfo66OzGNnKttd7JGaVSJ05NkwDFaM9EXDoGw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=htW9Vz04; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="htW9Vz04" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1763132795; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=0EVYMqufOoIHV82nAeE2u6YNjD+PUPB4KvH6NE2Jsio=; b=htW9Vz04YPShMoSF15pSEsSZ4BCiStOSl2PG9QHv8UkTNd4TQpuQAUE78RBwVALAa2sF5g 5y5xqIkjD8Kn7HpaiimF4TBwmxXm2BTcCxicTDSNvAuJoascmoqIbYSY19i9f0JVMvZW/5 ZHfRR8Ym+6TvPQBXhgHehdRLY/LzMwE= Received: from mx-prod-mc-03.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-404-cI01Fc2gNgiloAaXk9-ykA-1; Fri, 14 Nov 2025 10:06:33 -0500 X-MC-Unique: cI01Fc2gNgiloAaXk9-ykA-1 X-Mimecast-MFC-AGG-ID: cI01Fc2gNgiloAaXk9-ykA_1763132786 Received: from mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.12]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 4213318AB432; Fri, 14 Nov 2025 15:06:26 +0000 (UTC) Received: from vschneid-thinkpadt14sgen2i.remote.csb (unknown [10.45.226.10]) by mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 0671519560B9; Fri, 14 Nov 2025 15:06:12 +0000 (UTC) From: Valentin Schneider To: linux-kernel@vger.kernel.org, linux-mm@kvack.org, rcu@vger.kernel.org, x86@kernel.org, linux-arm-kernel@lists.infradead.org, loongarch@lists.linux.dev, linux-riscv@lists.infradead.org, linux-arch@vger.kernel.org, linux-trace-kernel@vger.kernel.org Cc: Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , "H. Peter Anvin" , Andy Lutomirski , Peter Zijlstra , Arnaldo Carvalho de Melo , Josh Poimboeuf , Paolo Bonzini , Arnd Bergmann , Frederic Weisbecker , "Paul E. McKenney" , Jason Baron , Steven Rostedt , Ard Biesheuvel , Sami Tolvanen , "David S. Miller" , Neeraj Upadhyay , Joel Fernandes , Josh Triplett , Boqun Feng , Uladzislau Rezki , Mathieu Desnoyers , Mel Gorman , Andrew Morton , Masahiro Yamada , Han Shen , Rik van Riel , Jann Horn , Dan Carpenter , Oleg Nesterov , Juri Lelli , Clark Williams , Yair Podemsky , Marcelo Tosatti , Daniel Wagner , Petr Tesarik , Shrikanth Hegde Subject: [PATCH v7 17/31] x86/bugs: Mark cpu_buf_vm_clear key as allowed in .noinstr Date: Fri, 14 Nov 2025 16:01:19 +0100 Message-ID: <20251114150133.1056710-18-vschneid@redhat.com> In-Reply-To: <20251114150133.1056710-1-vschneid@redhat.com> References: <20251114150133.1056710-1-vschneid@redhat.com> Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 3.0 on 10.30.177.12 The static key is only ever updated in __init mmio_apply_mitigation Mark it to let objtool know not to warn about it. Signed-off-by: Valentin Schneider --- arch/x86/kernel/cpu/bugs.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c index d7fa03bf51b45..a2d7dc4d2a4a3 100644 --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -196,8 +196,11 @@ DEFINE_STATIC_KEY_FALSE(switch_mm_cond_l1d_flush); * Controls CPU Fill buffer clear before VMenter. This is a subset of * X86_FEATURE_CLEAR_CPU_BUF, and should only be enabled when KVM-only * mitigation is required. + * + * NOINSTR: This static key is only updated during init, so it can't be + * a cause of post-init interference. */ -DEFINE_STATIC_KEY_FALSE(cpu_buf_vm_clear); +DEFINE_STATIC_KEY_FALSE_NOINSTR(cpu_buf_vm_clear); EXPORT_SYMBOL_GPL(cpu_buf_vm_clear); #undef pr_fmt -- 2.51.0