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 9B2C1C433EF for ; Tue, 29 Mar 2022 08:52:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234308AbiC2Ixx (ORCPT ); Tue, 29 Mar 2022 04:53:53 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42264 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234268AbiC2Ixf (ORCPT ); Tue, 29 Mar 2022 04:53:35 -0400 Received: from mail-oi1-x22d.google.com (mail-oi1-x22d.google.com [IPv6:2607:f8b0:4864:20::22d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 53C0065D11 for ; Tue, 29 Mar 2022 01:51:52 -0700 (PDT) Received: by mail-oi1-x22d.google.com with SMTP id 12so18350310oix.12 for ; Tue, 29 Mar 2022 01:51:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=R1lsy9bMwR3ErUveqedAk8smNA0HigoGBjxLcyNF7Hk=; b=rbrvbYiedyRBSdRYe6ZGpIj7XvntHQia/rB4xtJJLFMus5eHqW8Pemvzxfr7NXac3+ JMagcc+W0AMpYApVy0+MqLkvwibf2VVZpVXknche0g03NNv8sC8YGGdNshJ1aeGD77Vq +NUWztvMoJTf0Essh7f73pRj5H7P9WnWHuDIvQsYVAGDITzwiCixYW/cSEru53TjZ0uy 9LwegnaV7o/2eVro98LRwh5SbzGJfPzrHl/3oY0n4GZr/fNy/fW3o39UrP7PGtNZ8+Po Y11i0R1NhlQOcMom/HNueNTgjCC0DqT2Wm5JQAvSRD1NFwVqYJD/GePT68iWk1buWSjB qByg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=R1lsy9bMwR3ErUveqedAk8smNA0HigoGBjxLcyNF7Hk=; b=DyF5CtTb58klR94UPHSki79fTmr5t1sVa2ona0le3riimHWwM9hGaTkQa0Al9OpqKW WZo/5ba4wiLcS/s47G9axS3sQa5F7R0vqXVgDA98mdH/ZxwV8cM3Ff98VW4z7tzA0U+/ vGVeyAl4sQEdJUKYvVIUwKx5ju3PpdsiWL6e5jM6qFr5xQF8iRlT8lbCVd8K0DMeiRf+ OsP0Sl/2vD/b8PfDo+3x01GII57wCrHAqJcnqoBD1Y518yDbgNMbX8FOCDXbAFPEAbC5 /KBeR5bCszehrTgiG9zEkw1xkx6c01ffn58PpxhXKjw7urtT5H8Mqm7yT+aKmmXT4D8B ZFXA== X-Gm-Message-State: AOAM5306p5d5tHBU7SlLBK9sx57jmPgDgUvdheqRbBf4l937RahjLnSG ePLQQPWybnAw4JXKUGDz4b62CDBKF/Rw46f7qqqlIQ== X-Google-Smtp-Source: ABdhPJy/th1u/rMCaWZtzYowW7LJ1M2NUGV8icqQ2gVGgJiqN6PQR2SlsJkh6eQ+HBd+YiFyvJrCKH5iVJxXzxXwfpc= X-Received: by 2002:aca:180b:0:b0:2f7:23ae:8cd1 with SMTP id h11-20020aca180b000000b002f723ae8cd1mr1592160oih.146.1648543911401; Tue, 29 Mar 2022 01:51:51 -0700 (PDT) MIME-Version: 1.0 References: <20220314200148.2695206-1-kaleshsingh@google.com> <20220314200148.2695206-9-kaleshsingh@google.com> In-Reply-To: <20220314200148.2695206-9-kaleshsingh@google.com> From: Fuad Tabba Date: Tue, 29 Mar 2022 09:51:15 +0100 Message-ID: Subject: Re: [PATCH v6 8/8] KVM: arm64: Symbolize the nVHE HYP backtrace To: Kalesh Singh Cc: will@kernel.org, maz@kernel.org, qperret@google.com, surenb@google.com, kernel-team@android.com, James Morse , Alexandru Elisei , Suzuki K Poulose , Catalin Marinas , Mark Rutland , Mark Brown , Masami Hiramatsu , Peter Collingbourne , "Madhavan T. Venkataraman" , Peter Zijlstra , Andrew Scull , Andrew Jones , Ard Biesheuvel , linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Kalesh, On Mon, Mar 14, 2022 at 8:07 PM Kalesh Singh wrote: > > Reintroduce the __kvm_nvhe_ symbols in kallsyms, ignoring the local > symbols in this namespace. The local symbols are not informative and > can cause aliasing issues when symbolizing the addresses. > > With the necessary symbols now in kallsyms we can symbolize nVHE > stacktrace addresses using the %pB print format specifier. > > Example call trace: > > [ 98.916444][ T426] kvm [426]: nVHE hyp panic at: [] __kvm_nvhe_overflow_stack+0x8/0x34! > [ 98.918360][ T426] nVHE HYP call trace: > [ 98.918692][ T426] kvm [426]: [] __kvm_nvhe_cpu_prepare_nvhe_panic_info+0x4c/0x68 > [ 98.919545][ T426] kvm [426]: [] __kvm_nvhe_hyp_panic+0x2c/0xe8 > [ 98.920107][ T426] kvm [426]: [] __kvm_nvhe_hyp_panic_bad_stack+0x10/0x10 > [ 98.920665][ T426] kvm [426]: [] __kvm_nvhe___kvm_hyp_host_vector+0x24c/0x794 > [ 98.921292][ T426] kvm [426]: [] __kvm_nvhe_overflow_stack+0x24/0x34 > . . . > > [ 98.973382][ T426] kvm [426]: [] __kvm_nvhe_overflow_stack+0x24/0x34 > [ 98.973816][ T426] kvm [426]: [] __kvm_nvhe___kvm_vcpu_run+0x38/0x438 > [ 98.974255][ T426] kvm [426]: [] __kvm_nvhe_handle___kvm_vcpu_run+0x1c4/0x364 > [ 98.974719][ T426] kvm [426]: [] __kvm_nvhe_handle_trap+0xa8/0x130 > [ 98.975152][ T426] kvm [426]: [] __kvm_nvhe___host_exit+0x64/0x64 > [ 98.975588][ T426] ---- end of nVHE HYP call trace ---- > > Signed-off-by: Kalesh Singh Tested-by: Fuad Tabba Reviewed-by: Fuad Tabba Thanks, /fuad > --- > > Changes in v2: > - Fix printk warnings - %p expects (void *) > > > arch/arm64/kvm/handle_exit.c | 13 +++++-------- > scripts/kallsyms.c | 2 +- > 2 files changed, 6 insertions(+), 9 deletions(-) > > diff --git a/arch/arm64/kvm/handle_exit.c b/arch/arm64/kvm/handle_exit.c > index ff69dff33700..3a5c32017c6b 100644 > --- a/arch/arm64/kvm/handle_exit.c > +++ b/arch/arm64/kvm/handle_exit.c > @@ -296,13 +296,8 @@ void __noreturn __cold nvhe_hyp_panic_handler(u64 esr, u64 spsr, > u64 elr_in_kimg = __phys_to_kimg(elr_phys); > u64 hyp_offset = elr_in_kimg - kaslr_offset() - elr_virt; > u64 mode = spsr & PSR_MODE_MASK; > + u64 panic_addr = elr_virt + hyp_offset; > > - /* > - * The nVHE hyp symbols are not included by kallsyms to avoid issues > - * with aliasing. That means that the symbols cannot be printed with the > - * "%pS" format specifier, so fall back to the vmlinux address if > - * there's no better option. > - */ > if (mode != PSR_MODE_EL2t && mode != PSR_MODE_EL2h) { > kvm_err("Invalid host exception to nVHE hyp!\n"); > } else if (ESR_ELx_EC(esr) == ESR_ELx_EC_BRK64 && > @@ -322,9 +317,11 @@ void __noreturn __cold nvhe_hyp_panic_handler(u64 esr, u64 spsr, > if (file) > kvm_err("nVHE hyp BUG at: %s:%u!\n", file, line); > else > - kvm_err("nVHE hyp BUG at: %016llx!\n", elr_virt + hyp_offset); > + kvm_err("nVHE hyp BUG at: [<%016llx>] %pB!\n", panic_addr, > + (void *)panic_addr); > } else { > - kvm_err("nVHE hyp panic at: %016llx!\n", elr_virt + hyp_offset); > + kvm_err("nVHE hyp panic at: [<%016llx>] %pB!\n", panic_addr, > + (void *)panic_addr); > } > > kvm_nvhe_dump_backtrace(hyp_offset); > diff --git a/scripts/kallsyms.c b/scripts/kallsyms.c > index 54ad86d13784..19aba43d9da4 100644 > --- a/scripts/kallsyms.c > +++ b/scripts/kallsyms.c > @@ -111,7 +111,7 @@ static bool is_ignored_symbol(const char *name, char type) > ".LASANPC", /* s390 kasan local symbols */ > "__crc_", /* modversions */ > "__efistub_", /* arm64 EFI stub namespace */ > - "__kvm_nvhe_", /* arm64 non-VHE KVM namespace */ > + "__kvm_nvhe_$", /* arm64 local symbols in non-VHE KVM namespace */ > "__AArch64ADRPThunk_", /* arm64 lld */ > "__ARMV5PILongThunk_", /* arm lld */ > "__ARMV7PILongThunk_", > -- > 2.35.1.723.g4982287a31-goog >