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=-6.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 8BE95C43603 for ; Tue, 10 Dec 2019 11:51:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5486020726 for ; Tue, 10 Dec 2019 11:51:39 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="fwmY4RUN" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727562AbfLJLvi (ORCPT ); Tue, 10 Dec 2019 06:51:38 -0500 Received: from us-smtp-2.mimecast.com ([207.211.31.81]:52890 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727504AbfLJLvf (ORCPT ); Tue, 10 Dec 2019 06:51:35 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1575978694; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=x85HLpSVXUpESKASgozyJonASmyTtrZ6tatnJUlwI+Y=; b=fwmY4RUNHgViFDe6a6kLc0HjP9yzFkJFhlXnEYEewwhe7XZoqUHx5EQK0hivqgoZxw+HQV KuGc2WkkoDfaMgArapt0zOabg2cbCAJ3umEPKYqOlX0KNse8hyZdmTedNfqr740C9d4L/O zPY8YyXflpdIS+nKImyMkcRSuZqxk6o= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-415-gpWyPKUJNL-J9E7vhKGKIA-1; Tue, 10 Dec 2019 06:51:30 -0500 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 3C78580440F; Tue, 10 Dec 2019 11:51:28 +0000 (UTC) Received: from shalem.localdomain.com (unknown [10.36.118.144]) by smtp.corp.redhat.com (Postfix) with ESMTP id A23065DA60; Tue, 10 Dec 2019 11:51:24 +0000 (UTC) From: Hans de Goede To: Ard Biesheuvel , Darren Hart , Andy Shevchenko , Luis Chamberlain , Greg Kroah-Hartman , "Rafael J . Wysocki" , Thomas Gleixner , Ingo Molnar , Borislav Petkov , "H . Peter Anvin" , Jonathan Corbet , Dmitry Torokhov Cc: Hans de Goede , Peter Jones , Dave Olsthoorn , x86@kernel.org, platform-driver-x86@vger.kernel.org, linux-efi@vger.kernel.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-input@vger.kernel.org Subject: [PATCH v10 01/10] efi: Export boot-services code and data as debugfs-blobs Date: Tue, 10 Dec 2019 12:51:08 +0100 Message-Id: <20191210115117.303935-2-hdegoede@redhat.com> In-Reply-To: <20191210115117.303935-1-hdegoede@redhat.com> References: <20191210115117.303935-1-hdegoede@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-MC-Unique: gpWyPKUJNL-J9E7vhKGKIA-1 X-Mimecast-Spam-Score: 0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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=3Ddebug is passed on the kernel-commandline as this require= s not freeing those memory-regions, which costs 20+ MB of RAM. Reviewed-by: Greg Kroah-Hartman Acked-by: Ard Biesheuvel Signed-off-by: Hans de Goede --- Changes in v8: -Add pr_warn if there are mode then EFI_DEBUGFS_MAX_BLOBS boot service segm= ents -Document how the boot_service_code? files can be used to check for embedde= d firmware. Note since this is related to the firmware EFI embedded fw suppo= rt, these docs are added in the 4th patch of this patch-set, not in this one. Changes in v5: -Rename the EFI_BOOT_SERVICES flag to EFI_PRESERVE_BS_REGIONS Changes in v4: -Add new EFI_BOOT_SERVICES flag and use it to determine if the boot-service= s memory segments are available (and thus if it makes sense to register the debugfs bits for them) Changes in v2: -Do not call pr_err on debugfs call failures --- arch/x86/platform/efi/efi.c | 1 + arch/x86/platform/efi/quirks.c | 4 +++ drivers/firmware/efi/efi.c | 57 ++++++++++++++++++++++++++++++++++ include/linux/efi.h | 1 + 4 files changed, 63 insertions(+) diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c index 38d44f36d5ed..3e5375ee53a0 100644 --- a/arch/x86/platform/efi/efi.c +++ b/arch/x86/platform/efi/efi.c @@ -269,6 +269,7 @@ int __init efi_memblock_x86_reserve_range(void) =09 efi.memmap.desc_version); =20 =09memblock_reserve(pmap, efi.memmap.nr_map * efi.memmap.desc_size); +=09set_bit(EFI_PRESERVE_BS_REGIONS, &efi.flags); =20 =09return 0; } diff --git a/arch/x86/platform/efi/quirks.c b/arch/x86/platform/efi/quirks.= c index 7675cf754d90..84a9de64e8e1 100644 --- a/arch/x86/platform/efi/quirks.c +++ b/arch/x86/platform/efi/quirks.c @@ -414,6 +414,10 @@ void __init efi_free_boot_services(void) =09int num_entries =3D 0; =09void *new, *new_md; =20 +=09/* Keep all regions for /sys/kernel/debug/efi */ +=09if (efi_enabled(EFI_DBG)) +=09=09return; + =09for_each_efi_memory_desc(md) { =09=09unsigned long long start =3D md->phys_addr; =09=09unsigned long long size =3D md->num_pages << EFI_PAGE_SHIFT; diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c index d101f072c8f8..7575401e6ea6 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -17,6 +17,7 @@ #include #include #include +#include #include #include #include @@ -325,6 +326,59 @@ static __init int efivar_ssdt_load(void) static inline int efivar_ssdt_load(void) { return 0; } #endif =20 +#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) +{ +=09struct dentry *efi_debugfs; +=09efi_memory_desc_t *md; +=09char name[32]; +=09int type_count[EFI_BOOT_SERVICES_DATA + 1] =3D {}; +=09int i =3D 0; + +=09efi_debugfs =3D debugfs_create_dir("efi", NULL); +=09if (IS_ERR_OR_NULL(efi_debugfs)) +=09=09return; + +=09for_each_efi_memory_desc(md) { +=09=09switch (md->type) { +=09=09case EFI_BOOT_SERVICES_CODE: +=09=09=09snprintf(name, sizeof(name), "boot_services_code%d", +=09=09=09=09 type_count[md->type]++); +=09=09=09break; +=09=09case EFI_BOOT_SERVICES_DATA: +=09=09=09snprintf(name, sizeof(name), "boot_services_data%d", +=09=09=09=09 type_count[md->type]++); +=09=09=09break; +=09=09default: +=09=09=09continue; +=09=09} + +=09=09if (i >=3D EFI_DEBUGFS_MAX_BLOBS) { +=09=09=09pr_warn("More then %d EFI boot service segments, only showing fir= st %d in debugfs\n", +=09=09=09=09EFI_DEBUGFS_MAX_BLOBS, EFI_DEBUGFS_MAX_BLOBS); +=09=09=09break; +=09=09} + +=09=09debugfs_blob[i].size =3D md->num_pages << EFI_PAGE_SHIFT; +=09=09debugfs_blob[i].data =3D memremap(md->phys_addr, +=09=09=09=09=09=09debugfs_blob[i].size, +=09=09=09=09=09=09MEMREMAP_WB); +=09=09if (!debugfs_blob[i].data) +=09=09=09continue; + +=09=09debugfs_create_blob(name, 0400, efi_debugfs, &debugfs_blob[i]); +=09=09i++; +=09} +} +#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 @@ -381,6 +435,9 @@ static int __init efisubsys_init(void) =09=09goto err_remove_group; =09} =20 +=09if (efi_enabled(EFI_DBG) && efi_enabled(EFI_PRESERVE_BS_REGIONS)) +=09=09efi_debugfs_init(); + =09return 0; =20 err_remove_group: diff --git a/include/linux/efi.h b/include/linux/efi.h index 99dfea595c8c..c364106250e9 100644 --- a/include/linux/efi.h +++ b/include/linux/efi.h @@ -1203,6 +1203,7 @@ extern int __init efi_setup_pcdp_console(char *); #define EFI_NX_PE_DATA=09=099=09/* Can runtime data regions be mapped non-= executable? */ #define EFI_MEM_ATTR=09=0910=09/* Did firmware publish an EFI_MEMORY_ATTRI= BUTES table? */ #define EFI_MEM_NO_SOFT_RESERVE=0911=09/* Is the kernel configured to igno= re soft reservations? */ +#define EFI_PRESERVE_BS_REGIONS=0912=09/* Are EFI boot-services memory seg= ments available? */ =20 #ifdef CONFIG_EFI /* --=20 2.23.0