From patchwork Sun Apr 8 17:26:32 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hans de Goede X-Patchwork-Id: 10328413 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id DA864604D4 for ; Sun, 8 Apr 2018 17:27:57 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id CA3EF2841D for ; Sun, 8 Apr 2018 17:27:57 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id BC9062846D; Sun, 8 Apr 2018 17:27:57 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00, MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 69DDF2841D for ; Sun, 8 Apr 2018 17:27:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752517AbeDHR0t (ORCPT ); Sun, 8 Apr 2018 13:26:49 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:35278 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752220AbeDHR0q (ORCPT ); Sun, 8 Apr 2018 13:26:46 -0400 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.rdu2.redhat.com [10.11.54.3]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id A3AAC77067; Sun, 8 Apr 2018 17:26:45 +0000 (UTC) Received: from shalem.localdomain.com (ovpn-116-39.ams2.redhat.com [10.36.116.39]) by smtp.corp.redhat.com (Postfix) with ESMTP id 14D931101E88; Sun, 8 Apr 2018 17:26:41 +0000 (UTC) From: Hans de Goede To: Darren Hart , Andy Shevchenko , Ard Biesheuvel , "Luis R . Rodriguez" , Greg Kroah-Hartman , Thomas Gleixner , Ingo Molnar , "H . Peter Anvin" Cc: Hans de Goede , platform-driver-x86@vger.kernel.org, linux-kernel@vger.kernel.org, Peter Jones , Dave Olsthoorn , Will Deacon , Andy Lutomirski , Matt Fleming , David Howells , Mimi Zohar , Josh Triplett , dmitry.torokhov@gmail.com, mfuzzey@parkeon.com, keescook@chromium.org, Kalle Valo , Arend Van Spriel , Linus Torvalds , nbroeking@me.com, bjorn.andersson@linaro.org, Torsten Duwe , x86@kernel.org, linux-efi@vger.kernel.org Subject: [PATCH v2 1/5] efi: Export boot-services code and data as debugfs-blobs Date: Sun, 8 Apr 2018 19:26:32 +0200 Message-Id: <20180408172636.13926-2-hdegoede@redhat.com> In-Reply-To: <20180408172636.13926-1-hdegoede@redhat.com> References: <20180408172636.13926-1-hdegoede@redhat.com> X-Scanned-By: MIMEDefang 2.78 on 10.11.54.3 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.1]); Sun, 08 Apr 2018 17:26:45 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.1]); Sun, 08 Apr 2018 17:26:45 +0000 (UTC) for IP:'10.11.54.3' DOMAIN:'int-mx03.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'hdegoede@redhat.com' RCPT:'' Sender: platform-driver-x86-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: platform-driver-x86@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Sometimes it is useful to be able to dump the efi boot-services code and data. This commit adds these as debugfs-blobs to /sys/kernel/debug/efi, but only if efi=debug is passed on the kernel-commandline as this requires not freeing those memory-regions, which costs 20+ MB of RAM. Signed-off-by: Hans de Goede --- Changes in v2: -Do not call pr_err on debugfs call failures --- arch/x86/platform/efi/quirks.c | 4 +++ drivers/firmware/efi/efi.c | 53 ++++++++++++++++++++++++++++++++++ 2 files changed, 57 insertions(+) diff --git a/arch/x86/platform/efi/quirks.c b/arch/x86/platform/efi/quirks.c index 5b513ccffde4..0f968c7bcfec 100644 --- a/arch/x86/platform/efi/quirks.c +++ b/arch/x86/platform/efi/quirks.c @@ -374,6 +374,10 @@ void __init efi_free_boot_services(void) int num_entries = 0; void *new, *new_md; + /* Keep all regions for /sys/kernel/debug/efi */ + if (efi_enabled(EFI_DBG)) + return; + for_each_efi_memory_desc(md) { unsigned long long start = md->phys_addr; unsigned long long size = md->num_pages << EFI_PAGE_SHIFT; diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c index cd42f66a7c85..10c896e8b82b 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -18,6 +18,7 @@ #include #include #include +#include #include #include #include @@ -316,6 +317,55 @@ static __init int efivar_ssdt_load(void) static inline int efivar_ssdt_load(void) { return 0; } #endif +#ifdef CONFIG_DEBUG_FS + +#define EFI_DEBUGFS_MAX_BLOBS 32 + +static struct debugfs_blob_wrapper debugfs_blob[EFI_DEBUGFS_MAX_BLOBS]; + +static void __init efi_debugfs_init(void) +{ + struct dentry *efi_debugfs; + efi_memory_desc_t *md; + char name[32]; + int type_count[EFI_BOOT_SERVICES_DATA + 1] = {}; + int i = 0; + + efi_debugfs = debugfs_create_dir("efi", NULL); + if (IS_ERR_OR_NULL(efi_debugfs)) + return; + + for_each_efi_memory_desc(md) { + switch (md->type) { + case EFI_BOOT_SERVICES_CODE: + snprintf(name, sizeof(name), "boot_services_code%d", + type_count[md->type]++); + break; + case EFI_BOOT_SERVICES_DATA: + snprintf(name, sizeof(name), "boot_services_data%d", + type_count[md->type]++); + break; + default: + continue; + } + + debugfs_blob[i].size = md->num_pages << EFI_PAGE_SHIFT; + debugfs_blob[i].data = memremap(md->phys_addr, + debugfs_blob[i].size, + MEMREMAP_WB); + if (!debugfs_blob[i].data) + continue; + + debugfs_create_blob(name, 0400, efi_debugfs, &debugfs_blob[i]); + i++; + if (i == EFI_DEBUGFS_MAX_BLOBS) + break; + } +} +#else +static inline void efi_debugfs_init(void) {} +#endif + /* * We register the efi subsystem with the firmware subsystem and the * efivars subsystem with the efi subsystem, if the system was booted with @@ -360,6 +410,9 @@ static int __init efisubsys_init(void) goto err_remove_group; } + if (efi_enabled(EFI_DBG)) + efi_debugfs_init(); + return 0; err_remove_group: