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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 929A8C433EF for ; Thu, 21 Jul 2022 05:58:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231800AbiGUF6k (ORCPT ); Thu, 21 Jul 2022 01:58:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46934 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231529AbiGUF6O (ORCPT ); Thu, 21 Jul 2022 01:58:14 -0400 Received: from mail-yb1-xb4a.google.com (mail-yb1-xb4a.google.com [IPv6:2607:f8b0:4864:20::b4a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B42DF79EED for ; Wed, 20 Jul 2022 22:58:13 -0700 (PDT) Received: by mail-yb1-xb4a.google.com with SMTP id v1-20020a259d81000000b0066ec7dff8feso570981ybp.18 for ; Wed, 20 Jul 2022 22:58:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=POF5DiWqY8exBmivz0rKj4swn88HJpD6BS/y4rmGEUs=; b=iNF3/wKiZxQkHHbeWmrDPvF2lTugngVT8l6YAy7ij5cPY90sHRbAuAte+7t0gXkHM8 Nn10K9x+jyiPRlfMiH8Kme8pJx4iK86w/tvNiOBAB1RJwhX9HgF7aG5TgxWlxjs/+aC8 JmrWVdRF1+4cai70BJHNbLhfq+tLYGoZ6LLzkBFW+Nr9qdq5HvnnSMO3BS2WFS59TMNg LZGWa/1Ri7/0xL/cgFTo4eKFiFrQxY3DxKk8iLGThqSBtt9m+qrvIc1e+4lqd4jVScfj zAqxL3KDqT2/e+X/RiSP6BCUWHdY0bJGvcENptvBCIFJV6C4TR6EHm0MT+/+Kbjg1Kil auXw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=POF5DiWqY8exBmivz0rKj4swn88HJpD6BS/y4rmGEUs=; b=jCr47pzVJIm1nulvy20mucoUG/E64rzUoX8fogTdHtopchSEHAoEB8X9r5JBGEUuY2 qyVEYTVZOXTZHwxdvVTGO5UDhE+71YwDVPuc4M8eSjNxF+jIDkZvLyx5AdTn9ov+vb46 RwNGTorfOqC2M858pOv0rkFaYGBIZ6bsjRX271hIG+fHPwNnpAhCBvoCED52xLCxfiBk LSRasfUulHh0AjzUo/5K2xdEjkYwunVkAlbtDwGqHuYgZZ5m3FFtYmm0vLUi4r3RmyVo bwx9wf8tOoUb270fo5YGvDoMkG7fJ8lL0/bTUsISH5LoMJte3ZH2zwBOMI+DDXquqJcD XB+A== X-Gm-Message-State: AJIora/Z8WijRGLsw5dbsFC7ZwEHGjwj3n4BfkldMEyGlDMhatrVMb4Q Iyg/dfqA9AKuC76guBAyvdpdfNuaSunuC9vXOQ== X-Google-Smtp-Source: AGRyM1s1aoVE6pG6u4uUcd7EnheOT1wFEk50XabWGsXZv3DmsYR0UuXWQPe2QHeoCAY/ooJghIm8SbcDhywackPmqQ== X-Received: from kaleshsingh.mtv.corp.google.com ([2620:15c:211:200:5a87:b61e:76b5:d1e0]) (user=kaleshsingh job=sendgmr) by 2002:a25:d614:0:b0:670:9ea2:e6c1 with SMTP id n20-20020a25d614000000b006709ea2e6c1mr4776973ybg.379.1658383093469; Wed, 20 Jul 2022 22:58:13 -0700 (PDT) Date: Wed, 20 Jul 2022 22:57:27 -0700 In-Reply-To: <20220721055728.718573-1-kaleshsingh@google.com> Message-Id: <20220721055728.718573-17-kaleshsingh@google.com> Mime-Version: 1.0 References: <20220721055728.718573-1-kaleshsingh@google.com> X-Mailer: git-send-email 2.37.0.170.g444d1eabd0-goog Subject: [PATCH v5 16/17] KVM: arm64: Introduce pkvm_dump_backtrace() From: Kalesh Singh To: maz@kernel.org, mark.rutland@arm.com, broonie@kernel.org, madvenka@linux.microsoft.com, tabba@google.com Cc: will@kernel.org, qperret@google.com, kaleshsingh@google.com, james.morse@arm.com, alexandru.elisei@arm.com, suzuki.poulose@arm.com, catalin.marinas@arm.com, andreyknvl@gmail.com, vincenzo.frascino@arm.com, mhiramat@kernel.org, ast@kernel.org, drjones@redhat.com, wangkefeng.wang@huawei.com, elver@google.com, keirf@google.com, yuzenghui@huawei.com, ardb@kernel.org, oupton@google.com, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, linux-kernel@vger.kernel.org, android-mm@google.com, kernel-team@android.com Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Dumps the pKVM hypervisor backtrace from EL1 by reading the unwinded addresses from the shared stacktrace buffer. The nVHE hyp backtrace is dumped on hyp_panic(), before panicking the host. Signed-off-by: Kalesh Singh --- Changes in v5: - Move code out from nvhe.h header to handle_exit.c, per Marc - Fix stacktrace symoblization when CONFIG_RAMDOMIZE_BASE is enabled, per Fuad - Use regular comments instead of doc comments, per Fuad arch/arm64/kvm/handle_exit.c | 54 ++++++++++++++++++++++++++++++++++++ 1 file changed, 54 insertions(+) diff --git a/arch/arm64/kvm/handle_exit.c b/arch/arm64/kvm/handle_exit.c index f66c0142b335..ad568da5c7d7 100644 --- a/arch/arm64/kvm/handle_exit.c +++ b/arch/arm64/kvm/handle_exit.c @@ -318,6 +318,57 @@ void handle_exit_early(struct kvm_vcpu *vcpu, int exception_index) kvm_handle_guest_serror(vcpu, kvm_vcpu_get_esr(vcpu)); } +#ifdef CONFIG_PROTECTED_NVHE_STACKTRACE +DECLARE_KVM_NVHE_PER_CPU(unsigned long [NVHE_STACKTRACE_SIZE/sizeof(long)], + pkvm_stacktrace); + +/* + * pkvm_dump_backtrace - Dump the protected nVHE HYP backtrace. + * + * @hyp_offset: hypervisor offset, used for address translation. + * + * Dumping of the pKVM HYP backtrace is done by reading the + * stack addresses from the shared stacktrace buffer, since the + * host cannot direclty access hyperviosr memory in protected + * mode. + */ +static void pkvm_dump_backtrace(unsigned long hyp_offset) +{ + unsigned long *stacktrace_entry + = (unsigned long *)this_cpu_ptr_nvhe_sym(pkvm_stacktrace); + unsigned long va_mask, pc; + + va_mask = GENMASK_ULL(vabits_actual - 1, 0); + + kvm_err("Protected nVHE HYP call trace:\n"); + + /* The stack trace is terminated by a null entry */ + for (; *stacktrace_entry; stacktrace_entry++) { + /* Mask tags and convert to kern addr */ + pc = (*stacktrace_entry & va_mask) + hyp_offset; + kvm_err(" [<%016lx>] %pB\n", pc, (void *)(pc + kaslr_offset())); + } + + kvm_err("---- End of Protected nVHE HYP call trace ----\n"); +} +#else /* !CONFIG_PROTECTED_NVHE_STACKTRACE */ +static void pkvm_dump_backtrace(unsigned long hyp_offset) +{ + kvm_err("Cannot dump pKVM nVHE stacktrace: !CONFIG_PROTECTED_NVHE_STACKTRACE\n"); +} +#endif /* CONFIG_PROTECTED_NVHE_STACKTRACE */ + +/* + * kvm_nvhe_dump_backtrace - Dump KVM nVHE hypervisor backtrace. + * + * @hyp_offset: hypervisor offset, used for address translation. + */ +static void kvm_nvhe_dump_backtrace(unsigned long hyp_offset) +{ + if (is_protected_kvm_enabled()) + pkvm_dump_backtrace(hyp_offset); +} + void __noreturn __cold nvhe_hyp_panic_handler(u64 esr, u64 spsr, u64 elr_virt, u64 elr_phys, u64 par, uintptr_t vcpu, @@ -353,6 +404,9 @@ void __noreturn __cold nvhe_hyp_panic_handler(u64 esr, u64 spsr, (void *)panic_addr); } + /* Dump the nVHE hypervisor backtrace */ + kvm_nvhe_dump_backtrace(hyp_offset); + /* * Hyp has panicked and we're going to handle that by panicking the * kernel. The kernel offset will be revealed in the panic so we're -- 2.37.0.170.g444d1eabd0-goog