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=-19.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 50192C43461 for ; Mon, 5 Apr 2021 16:05:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DF8B9613E7 for ; Mon, 5 Apr 2021 16:05:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239021AbhDEQF2 (ORCPT ); Mon, 5 Apr 2021 12:05:28 -0400 Received: from mail.kernel.org ([198.145.29.99]:56488 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242102AbhDEQEm (ORCPT ); Mon, 5 Apr 2021 12:04:42 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 527DE613AD; Mon, 5 Apr 2021 16:04:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1617638676; bh=edrHdlNwHoJ85Z4+U9rf8Th14sr62UQK7lx5Mw/15vA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=IUyMEbTXP8ibayHPh9S4di1+eSHp/cSfNMa+3hvJtBFcGjg8/ym9NNNlBy9FA9bUg I4ZH/7OH79s85QIQkSDSi7az9ypU1V4W1ZKAnevGskn8Yv+787Mj2oItIShGe0S9xm Hm4ippIW6i7hI0eeJYzEfkI4YLcbQhERdysIoAGsnIInSvNcb26VXHSuhz7A276rrv KILEQunYJKdI8AXfK7szYOjnF/u6z/+lnXuNmnWyJpILZMGDdsGC2tFpONt0l2yO+M pT8zScBDvlN0QjYUUkpfNWibFAtZn2cUtnNTzObwVYhCuKPyi10CZbfXnlX3vEpm2y yNTlRate+X5Hg== 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 5.10 03/22] KVM: arm64: Hide system instruction access to Trace registers Date: Mon, 5 Apr 2021 12:04:12 -0400 Message-Id: <20210405160432.268374-3-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210405160432.268374-1-sashal@kernel.org> References: <20210405160432.268374-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.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 7da9a7cee4ce..5001c43ea6c3 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -382,7 +382,6 @@ 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 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 89F59C43461 for ; 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h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=IUyMEbTXP8ibayHPh9S4di1+eSHp/cSfNMa+3hvJtBFcGjg8/ym9NNNlBy9FA9bUg I4ZH/7OH79s85QIQkSDSi7az9ypU1V4W1ZKAnevGskn8Yv+787Mj2oItIShGe0S9xm Hm4ippIW6i7hI0eeJYzEfkI4YLcbQhERdysIoAGsnIInSvNcb26VXHSuhz7A276rrv KILEQunYJKdI8AXfK7szYOjnF/u6z/+lnXuNmnWyJpILZMGDdsGC2tFpONt0l2yO+M pT8zScBDvlN0QjYUUkpfNWibFAtZn2cUtnNTzObwVYhCuKPyi10CZbfXnlX3vEpm2y yNTlRate+X5Hg== 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 5.10 03/22] KVM: arm64: Hide system instruction access to Trace registers Date: Mon, 5 Apr 2021 12:04:12 -0400 Message-Id: <20210405160432.268374-3-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210405160432.268374-1-sashal@kernel.org> References: <20210405160432.268374-1-sashal@kernel.org> 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_170510_844599_DB002590 X-CRM114-Status: GOOD ( 11.12 ) 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 7da9a7cee4ce..5001c43ea6c3 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -382,7 +382,6 @@ 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