From patchwork Thu Feb 25 19:35:32 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Suzuki K Poulose X-Patchwork-Id: 12104841 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=-16.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,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 70704C433E0 for ; Thu, 25 Feb 2021 19:38:31 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (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 0134464F2A for ; Thu, 25 Feb 2021 19:38:30 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0134464F2A Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=arm.com 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=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To:Message-Id:Date: Subject:To:From:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=z8HlezhrFLqwCFLRyrXywARxeL2PjlRRF4mfhijA4z4=; b=tJyJq1S+Zy6Wk2VOYrQGB9Dxp roLe1AEBzE3dPPEoIgOFsVVhEouUpFuR52gNyitmB7wGZbEFGKf5WixHodIgw7NLsRztRqigDurnW 7ltN9aXuYrlrDJd/P8nW2CqgTjubXSg6QJEIZH63hR3RxUE13LVkwj2SJNPD5GDzTp7VeMoLc09fS VT2MGaZvITN0tuaKVCC+FKatCm4VmkqLxj52aXTdNgGsxlPuOqd0DrUrvHaM/hbU96wb3oA/o37Cw Y+rKRiL6OR9i8NrF9ZopjrHZpJcd06bQLYMMxu0EE2elvMgQr1qwwiGKVTPxPAerRk57sLHpUVkTx gkmHbdpUg==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1lFMRc-0000Zd-Ae; Thu, 25 Feb 2021 19:37:04 +0000 Received: from foss.arm.com ([217.140.110.172]) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1lFMQl-0000CK-N4 for linux-arm-kernel@lists.infradead.org; Thu, 25 Feb 2021 19:36:13 +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 54E721435; Thu, 25 Feb 2021 11:36:11 -0800 (PST) Received: from ewhatever.cambridge.arm.com (ewhatever.cambridge.arm.com [10.1.197.1]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id DE3133F70D; Thu, 25 Feb 2021 11:36:09 -0800 (PST) From: Suzuki K Poulose To: linux-arm-kernel@lists.infradead.org Subject: [PATCH v4 08/19] arm64: kvm: Enable access to TRBE support for host Date: Thu, 25 Feb 2021 19:35:32 +0000 Message-Id: <20210225193543.2920532-9-suzuki.poulose@arm.com> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20210225193543.2920532-1-suzuki.poulose@arm.com> References: <20210225193543.2920532-1-suzuki.poulose@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210225_143611_972285_35FF0DC0 X-CRM114-Status: GOOD ( 21.22 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , Marc Zyngier , mathieu.poirier@linaro.org, anshuman.khandual@arm.com, Catalin Marinas , Suzuki K Poulose , linux-kernel@vger.kernel.org, leo.yan@linaro.org, Will Deacon , mike.leach@linaro.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org For a nvhe host, the EL2 must allow the EL1&0 translation regime for TraceBuffer (MDCR_EL2.E2TB == 0b11). This must be saved/restored over a trip to the guest. Also, before entering the guest, we must flush any trace data if the TRBE was enabled. And we must prohibit the generation of trace while we are in EL1 by clearing the TRFCR_EL1. For vhe, the EL2 must prevent the EL1 access to the Trace Buffer. Cc: Will Deacon Cc: Catalin Marinas Cc: Marc Zyngier Cc: Mark Rutland cc: Anshuman Khandual Signed-off-by: Suzuki K Poulose Acked-by: Mathieu Poirier --- Changes - Rebased to linux-next. - Re-enable TRBE access on host restore. - For nvhe, flush the trace and prohibit the trace while we are at guest. --- arch/arm64/include/asm/el2_setup.h | 13 +++++++++ arch/arm64/include/asm/kvm_arm.h | 2 ++ arch/arm64/include/asm/kvm_host.h | 2 ++ arch/arm64/kernel/hyp-stub.S | 3 ++- arch/arm64/kvm/debug.c | 6 ++--- arch/arm64/kvm/hyp/nvhe/debug-sr.c | 42 ++++++++++++++++++++++++++++++ arch/arm64/kvm/hyp/nvhe/switch.c | 1 + 7 files changed, 65 insertions(+), 4 deletions(-) diff --git a/arch/arm64/include/asm/el2_setup.h b/arch/arm64/include/asm/el2_setup.h index d77d358f9395..bda918948471 100644 --- a/arch/arm64/include/asm/el2_setup.h +++ b/arch/arm64/include/asm/el2_setup.h @@ -65,6 +65,19 @@ // use EL1&0 translation. .Lskip_spe_\@: + /* Trace buffer */ + ubfx x0, x1, #ID_AA64DFR0_TRBE_SHIFT, #4 + cbz x0, .Lskip_trace_\@ // Skip if TraceBuffer is not present + + mrs_s x0, SYS_TRBIDR_EL1 + and x0, x0, TRBIDR_PROG + cbnz x0, .Lskip_trace_\@ // If TRBE is available at EL2 + + mov x0, #(MDCR_EL2_E2TB_MASK << MDCR_EL2_E2TB_SHIFT) + orr x2, x2, x0 // allow the EL1&0 translation + // to own it. + +.Lskip_trace_\@: msr mdcr_el2, x2 // Configure debug traps .endm diff --git a/arch/arm64/include/asm/kvm_arm.h b/arch/arm64/include/asm/kvm_arm.h index 94d4025acc0b..692c9049befa 100644 --- a/arch/arm64/include/asm/kvm_arm.h +++ b/arch/arm64/include/asm/kvm_arm.h @@ -278,6 +278,8 @@ #define CPTR_EL2_DEFAULT CPTR_EL2_RES1 /* Hyp Debug Configuration Register bits */ +#define MDCR_EL2_E2TB_MASK (UL(0x3)) +#define MDCR_EL2_E2TB_SHIFT (UL(24)) #define MDCR_EL2_TTRF (1 << 19) #define MDCR_EL2_TPMS (1 << 14) #define MDCR_EL2_E2PB_MASK (UL(0x3)) diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 3d10e6527f7d..80d0a1a82a4c 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -315,6 +315,8 @@ struct kvm_vcpu_arch { struct kvm_guest_debug_arch regs; /* Statistical profiling extension */ u64 pmscr_el1; + /* Self-hosted trace */ + u64 trfcr_el1; } host_debug_state; /* VGIC state */ diff --git a/arch/arm64/kernel/hyp-stub.S b/arch/arm64/kernel/hyp-stub.S index 678cd2c618ee..ba84502b582a 100644 --- a/arch/arm64/kernel/hyp-stub.S +++ b/arch/arm64/kernel/hyp-stub.S @@ -115,9 +115,10 @@ SYM_CODE_START_LOCAL(mutate_to_vhe) mrs_s x0, SYS_VBAR_EL12 msr vbar_el1, x0 - // Use EL2 translations for SPE and disable access from EL1 + // Use EL2 translations for SPE & TRBE and disable access from EL1 mrs x0, mdcr_el2 bic x0, x0, #(MDCR_EL2_E2PB_MASK << MDCR_EL2_E2PB_SHIFT) + bic x0, x0, #(MDCR_EL2_E2TB_MASK << MDCR_EL2_E2TB_SHIFT) msr mdcr_el2, x0 // Transfer the MM state from EL1 to EL2 diff --git a/arch/arm64/kvm/debug.c b/arch/arm64/kvm/debug.c index dbc890511631..7b16f42d39f4 100644 --- a/arch/arm64/kvm/debug.c +++ b/arch/arm64/kvm/debug.c @@ -89,7 +89,7 @@ void kvm_arm_reset_debug_ptr(struct kvm_vcpu *vcpu) * - Debug ROM Address (MDCR_EL2_TDRA) * - OS related registers (MDCR_EL2_TDOSA) * - Statistical profiler (MDCR_EL2_TPMS/MDCR_EL2_E2PB) - * - Self-hosted Trace Filter controls (MDCR_EL2_TTRF) + * - Self-hosted Trace (MDCR_EL2_TTRF/MDCR_EL2_E2TB) * * Additionally, KVM only traps guest accesses to the debug registers if * the guest is not actively using them (see the KVM_ARM64_DEBUG_DIRTY @@ -107,8 +107,8 @@ void kvm_arm_setup_debug(struct kvm_vcpu *vcpu) trace_kvm_arm_setup_debug(vcpu, vcpu->guest_debug); /* - * This also clears MDCR_EL2_E2PB_MASK to disable guest access - * to the profiling buffer. + * This also clears MDCR_EL2_E2PB_MASK and MDCR_EL2_E2TB_MASK + * to disable guest access to the profiling and trace buffers */ vcpu->arch.mdcr_el2 = __this_cpu_read(mdcr_el2) & MDCR_EL2_HPMN_MASK; vcpu->arch.mdcr_el2 |= (MDCR_EL2_TPM | diff --git a/arch/arm64/kvm/hyp/nvhe/debug-sr.c b/arch/arm64/kvm/hyp/nvhe/debug-sr.c index f401724f12ef..9499e18dd28f 100644 --- a/arch/arm64/kvm/hyp/nvhe/debug-sr.c +++ b/arch/arm64/kvm/hyp/nvhe/debug-sr.c @@ -58,10 +58,51 @@ static void __debug_restore_spe(u64 pmscr_el1) write_sysreg_s(pmscr_el1, SYS_PMSCR_EL1); } +static void __debug_save_trace(u64 *trfcr_el1) +{ + + *trfcr_el1 = 0; + + /* Check if we have TRBE */ + if (!cpuid_feature_extract_unsigned_field(read_sysreg(id_aa64dfr0_el1), + ID_AA64DFR0_TRBE_SHIFT)) + return; + + /* Check we can access the TRBE */ + if ((read_sysreg_s(SYS_TRBIDR_EL1) & TRBIDR_PROG)) + return; + + /* Check if the TRBE is enabled */ + if (!(read_sysreg_s(SYS_TRBLIMITR_EL1) & TRBLIMITR_ENABLE)) + return; + /* + * Prohibit trace generation while we are in guest. + * Since access to TRFCR_EL1 is trapped, the guest can't + * modify the filtering set by the host. + */ + *trfcr_el1 = read_sysreg_s(SYS_TRFCR_EL1); + write_sysreg_s(0, SYS_TRFCR_EL1); + isb(); + /* Drain the trace buffer to memory */ + tsb_csync(); + dsb(nsh); +} + +static void __debug_restore_trace(u64 trfcr_el1) +{ + if (!trfcr_el1) + return; + + /* Restore trace filter controls */ + write_sysreg_s(trfcr_el1, SYS_TRFCR_EL1); +} + void __debug_save_host_buffers_nvhe(struct kvm_vcpu *vcpu) { /* Disable and flush SPE data generation */ __debug_save_spe(&vcpu->arch.host_debug_state.pmscr_el1); + /* Disable and flush Self-Hosted Trace generation */ + __debug_save_trace(&vcpu->arch.host_debug_state.trfcr_el1); } void __debug_switch_to_guest(struct kvm_vcpu *vcpu) @@ -72,6 +113,7 @@ void __debug_switch_to_guest(struct kvm_vcpu *vcpu) void __debug_restore_host_buffers_nvhe(struct kvm_vcpu *vcpu) { __debug_restore_spe(vcpu->arch.host_debug_state.pmscr_el1); + __debug_restore_trace(vcpu->arch.host_debug_state.trfcr_el1); } void __debug_switch_to_host(struct kvm_vcpu *vcpu) diff --git a/arch/arm64/kvm/hyp/nvhe/switch.c b/arch/arm64/kvm/hyp/nvhe/switch.c index 10eed66136a0..d6ea5c8b5551 100644 --- a/arch/arm64/kvm/hyp/nvhe/switch.c +++ b/arch/arm64/kvm/hyp/nvhe/switch.c @@ -95,6 +95,7 @@ static void __deactivate_traps(struct kvm_vcpu *vcpu) mdcr_el2 &= MDCR_EL2_HPMN_MASK; mdcr_el2 |= MDCR_EL2_E2PB_MASK << MDCR_EL2_E2PB_SHIFT; + mdcr_el2 |= MDCR_EL2_E2TB_MASK << MDCR_EL2_E2TB_SHIFT; write_sysreg(mdcr_el2, mdcr_el2); if (is_protected_kvm_enabled())