From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-17.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2554AC433B4 for ; Mon, 5 Apr 2021 16:14:45 +0000 (UTC) Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id B3AE961025 for ; Mon, 5 Apr 2021 16:14:44 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B3AE961025 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=desiato.20200630; h=Sender:Content-Transfer-Encoding :Content-Type:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version:Message-Id:Date:Subject:Cc:To:From: Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender :Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References:List-Owner; bh=zSkwgyglpgrmNkGHFbC171xFKkByEfLQibKM9H3GmRo=; b=iV4DcznGgheMvOWrqrWcmcRnAN ooxXrPI0jDuGuVUPn9nPIrW1ZX/FZ91d2tCMUx1ffzqY6V0jsvsrHfsxjmSMAW9Cmrv+JqXuNKBNt Owg9qNBxo13P1ve1r1N57+lxWqAvIPik7X1wb5ZsQF6CqNaAYqk+g+U+ZEtcIMIovc5thsQA/TLdP DG8c6gAf9tXddEgZcW0JnCvKZfPPjwiw3m3IY9Pt/+DUOQhk644Zx9o2lHBDbGMWHmy6CyuVAoVBf VRfi9fM85Q+53DzxKgtV0QbsbuqZ5rbKGy5fLKrRF5l8tOiA6u+fWhce97vcSHoC0OfRjQ869t/ld 4tznl7vw==; Received: from localhost ([::1] helo=desiato.infradead.org) by desiato.infradead.org with esmtp (Exim 4.94 #2 (Red Hat Linux)) id 1lTRqm-0002CI-V9; Mon, 05 Apr 2021 16:13:17 +0000 Received: from mail.kernel.org ([198.145.29.99]) by desiato.infradead.org with esmtps (Exim 4.94 #2 (Red Hat Linux)) id 1lTRjh-00Han6-FO for linux-arm-kernel@lists.infradead.org; Mon, 05 Apr 2021 16:06:50 +0000 Received: by mail.kernel.org (Postfix) with ESMTPSA id B46A0613C3; Mon, 5 Apr 2021 16:05:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1617638717; bh=XRLwauBjsFty1c92SC3fTmJm4Yvrr7casJYIy7PUltw=; h=From:To:Cc:Subject:Date:From; b=B/bw4J89nBgTk6Up+60FOO3IcUmnubVhBdfOg13CLGG14QUB1YW81+VTYgg3Ue6Kd 6WXgmF1JmasgV87/8giUDxQ6oG+lvcmHYj5VoxAnvBV4ek7yQrgPfQaNnMenFPPEvt GEnhaMlVpACANztTFexBF3WK6SQz9i4ahGSN5hk9DiNIIekSYdxLfUsKwW3E9UjufK rsCldxT+relV8iJ3kEr/CUmoQJ/epf8eWM0AFzWk8rg4D+W1zmeVCTr+MvrXMvWtNu ZldGnvYT/GSyOOE+QzMqS8eRUkLdB/FYJA/Px5IssecTQjNdt1e1JbM2tX/aOSNHEX kS8uoZ+J9lzFQ== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Suzuki K Poulose , Will Deacon , Catalin Marinas , Mark Rutland , Marc Zyngier , Sasha Levin , linux-arm-kernel@lists.infradead.org Subject: [PATCH AUTOSEL 4.19 1/8] KVM: arm64: Hide system instruction access to Trace registers Date: Mon, 5 Apr 2021 12:05:08 -0400 Message-Id: <20210405160515.269020-1-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210405_170558_924051_9D7E78C1 X-CRM114-Status: GOOD ( 10.73 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: Suzuki K Poulose [ Upstream commit 1d676673d665fd2162e7e466dcfbe5373bfdb73e ] Currently we advertise the ID_AA6DFR0_EL1.TRACEVER for the guest, when the trace register accesses are trapped (CPTR_EL2.TTA == 1). So, the guest will get an undefined instruction, if trusts the ID registers and access one of the trace registers. Lets be nice to the guest and hide the feature to avoid unexpected behavior. Even though this can be done at KVM sysreg emulation layer, we do this by removing the TRACEVER from the sanitised feature register field. This is fine as long as the ETM drivers can handle the individual trace units separately, even when there are differences among the CPUs. Cc: Will Deacon Cc: Catalin Marinas Cc: Mark Rutland Signed-off-by: Suzuki K Poulose Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20210323120647.454211-2-suzuki.poulose@arm.com Signed-off-by: Sasha Levin --- arch/arm64/kernel/cpufeature.c | 1 - 1 file changed, 1 deletion(-) diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index 1719d21a171a..122d5e843ab6 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -258,7 +258,6 @@ static const struct arm64_ftr_bits ftr_id_aa64dfr0[] = { * of support. */ S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_AA64DFR0_PMUVER_SHIFT, 4, 0), - ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, ID_AA64DFR0_TRACEVER_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_EXACT, ID_AA64DFR0_DEBUGVER_SHIFT, 4, 0x6), ARM64_FTR_END, }; -- 2.30.2 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel