From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 12CBC606A31C for ; Thu, 29 Oct 2026 21:15:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=lists.infradead.org header.i=@lists.infradead.org header.a=rsa-sha256 header.s=bombadil.20210309 header.b=NCtlox34; dkim=pass (1024-bit key, unprotected) header.d=arm.com header.i=@arm.com header.a=rsa-sha256 header.s=foss header.b=g8Ac2snP DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Unsubscribe-Post:List-Owner; bh=uUOoxh5FjWUwpph2LqQnLF50bqkpEqoE20tLRRD+3zY=; b=NCtlox34ojTWUDUvscjHGZMJZm sxSP5FaxuVXA/J4Plc+DYvRwxp57ZhkPD/QgLS+kcUyGVpa1ouicKB7w5NLL00rWRGW2z6XyvtFgX cei5VXiWNDFZqcdVxWJjKPOBhdAUhYGWXwp+Z6JtWdknglxXPp2PphV84VEHUPDg0IVYnC1TgXe/x ISnLVHraFFpRPYUH15Vs3ew7tPT/5VYXAREcGBTox6qeRByjadgtbF/uuwuMmkjyPtFPw1SfjSonN ah25mRY3y7l8tCpZcyAAq8XKWjRWUfT0yvlLvEiaIHXcVkRtV5jBOpDIw7ciERouCHtJGbZlgbTcu qEFSaQmw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.100.1 #2 (Red Hat Linux)) id 1xMXT6-0000000AOsM-0OD8; Thu, 29 Oct 2026 21:15:28 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.100.1 #2 (Red Hat Linux)) id 1xMXT3-0000000AOrf-2f1j for linux-arm-kernel@lists.infradead.org; Thu, 29 Oct 2026 21:15:26 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 5F6711682; Thu, 29 Oct 2026 14:15:19 -0700 (PDT) Received: from arm.com (usa-sjc-mx-foss1.foss.arm.com [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 5CED13F59E; Thu, 29 Oct 2026 14:15:20 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1793308522; bh=cLLb8kTBxnx4UA1bZ7blmuTf4w+v25p4Ofqywv52Tv8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=g8Ac2snP/yP6eE1gMl5eSWsRnObRxt4TKvv7JwVEnOV/kho0T5s+Ll5cxuy0oypZS OzFHVvh/5N8rSHvnPETiD9ah02AzfUsabo/JDjP9K5JkXElI053yHln7/VWq8aKRCp QOatav4wSox4p9lwpJ4gSOt/tbvtIl1Wc8PtPt4c= Date: Thu, 29 Oct 2026 21:15:18 +0000 From: Catalin Marinas To: Fuad Tabba Cc: Marc Zyngier , Oliver Upton , kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, Will Deacon , Joey Gouly , Suzuki K Poulose , Zenghui Yu , Steffen Eiden , Mark Rutland , Yicong Yang , Zhou Wang , Arnd Bergmann , Fuad Tabba , kvm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 3/5] KVM: arm64: Add context-switch of ACCDATA_EL1 Message-ID: References: <20261025075138.2919734-1-fuad.tabba@linux.dev> <20261025075138.2919734-4-fuad.tabba@linux.dev> X-Archived-By: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20261025075138.2919734-4-fuad.tabba@linux.dev> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20261029_141525_710637_E5239318 X-CRM114-Status: GOOD ( 12.44 ) X-Spam-Score: -4.4 (----) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" X-Spam-Status: No, score=-10.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=4.0.1 X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 On Sun, Oct 25, 2026 at 07:51:36AM +0000, Fuad Tabba wrote: > From: Marc Zyngier > > Add ACCDATA_EL1 save/restore as part of the EL0 context. This is > conditioned on the guest's view of ID_AA64ISAR1_EL1.LS64 reporting > that this register is supported. > > Signed-off-by: Marc Zyngier > Fixes: 58ce78667a641 ("arm64: Add support for FEAT_{LS64, LS64_V}") > Link: https://lore.kernel.org/r/20240815125959.2097734-5-maz@kernel.org > Cc: stable@vger.kernel.org > [Fuad: rebased; switch ACCDATA_EL1 for guests only, as the host never > uses it; gate it on a new ARM64_HAS_LS64_ACCDATA capability, since > in pKVM the host controls a non-protected guest's ID registers, and > an EL2 access to ACCDATA_EL1 on a CPU without the feature is UNDEFINED] > Signed-off-by: Fuad Tabba Acked-by: Catalin Marinas