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 9B136C433B4 for ; Mon, 5 Apr 2021 16:16:22 +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 24D16613AD for ; Mon, 5 Apr 2021 16:16:22 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 24D16613AD 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=NDYf3jUCBZsts7sIzAyP0IwiR3KRXY00c109GLzXUhU=; b=NB4Q3clcj9Mzlld2gzBp+1zpsn pz9mDY5SPtf9104jvGcWb2xLWaJPF2FT2n8OIv5+qE/IlKQxHVvCKVCTTjjuhlfEuLDPrIYqmJB4a EqMK/NXc62JYIAXFG50VEc2iq3FQ7E0MVs3lkNmDghutQ701jMrlGnuVcsUpqJD28bL4DUeEerepM 4eGBUl7UwQb9r1AnMsJrln10rpkaqSRkCWp4uhxyKkzmp+MVM9Rqx6QPzi+nYqNnFETbl0Hd1WjYr u5LavS5yB4/BA3Ho66dA/nsbk96UYViOMSTcONQ5KGveXg15M0R//EJidOjebqFJFdd5IVFVPkOa+ UeDVeHLA==; Received: from localhost ([::1] helo=desiato.infradead.org) by desiato.infradead.org with esmtp (Exim 4.94 #2 (Red Hat Linux)) id 1lTRsL-0002uM-0o; Mon, 05 Apr 2021 16:14:53 +0000 Received: from mail.kernel.org ([198.145.29.99]) by desiato.infradead.org with esmtps (Exim 4.94 #2 (Red Hat Linux)) id 1lTRjm-00HapF-96 for linux-arm-kernel@lists.infradead.org; Mon, 05 Apr 2021 16:06:56 +0000 Received: by mail.kernel.org (Postfix) with ESMTPSA id 12934613CB; Mon, 5 Apr 2021 16:05:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1617638728; bh=dWdpBlt/F8Ey2+xsNIcXAu7JRQ3UrZYAdUFlHh9MDtw=; h=From:To:Cc:Subject:Date:From; b=fgyi5wjLd1fEURAok8r5+QrtcZsQmfwAGvB4vcaKs0o1SMBh/GXpTJvh6zhE4rtqh QhtlbSndUIc0gHJVzJV5dJGGpCU6kRdRk0jWG0BXWv8PCTlcPXhB0nR4e9nYRUS1bV tZqRhMW7Uk0mBuR27qhtNmcZQdokLImsxpOmt6L/0ddKMV5V5wbcuK5WcNy2elrqpN jIhSyNJ0uTLNQC9x+BjH5ImrDRNFHWaX1nGTcJXnBypcqRqLjbISh6wbI6Mtry4V+9 n5hpK1r7XkKFPY1KLhGNzTEo2GIyKPh9cYAPt0/xv9GjNliaBqtb6ZLamZHMzgRqug weAguuWyaNtsQ== 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 4.14 1/5] KVM: arm64: Hide system instruction access to Trace registers Date: Mon, 5 Apr 2021 12:05:22 -0400 Message-Id: <20210405160526.269140-1-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_170603_068213_1174ED1C X-CRM114-Status: GOOD ( 10.94 ) 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 174aa12fb8b1..1481e18aa5ca 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -230,7 +230,6 @@ 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