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=-8.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,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 A4EF5C43382 for ; Thu, 27 Sep 2018 08:52:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4AD222157C for ; Thu, 27 Sep 2018 08:52:07 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=linaro.org header.i=@linaro.org header.b="NXYpuvfj" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4AD222157C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linaro.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727281AbeI0PIJ (ORCPT ); Thu, 27 Sep 2018 11:08:09 -0400 Received: from mail-wr1-f66.google.com ([209.85.221.66]:34548 "EHLO mail-wr1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726947AbeI0PII (ORCPT ); Thu, 27 Sep 2018 11:08:08 -0400 Received: by mail-wr1-f66.google.com with SMTP id z4-v6so286808wrb.1 for ; Thu, 27 Sep 2018 01:50:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=ffkuDpNBfwdcvOz+/QFFGB2qN+kuprFwPCetGXqXDvo=; b=NXYpuvfjVfvGDfKvcFzsqhfoZxbZh6uUyiF4tlEMs6UaniHzdsbXtC8B5wk1uDhj98 TQHp0JQrnCffiOTjDSjABSrHPhxtkbX93pvOd/liNxZtzbGLFivKuWpNnyo+XOLWfaWL fjc7qvSq5h98gKpG/Db2iG1jt+xScVrAfOFBo= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=ffkuDpNBfwdcvOz+/QFFGB2qN+kuprFwPCetGXqXDvo=; b=Ed79JRI+9Eqroa0SPVZKJ/2mpaPi/uemGIJo1dxRGwiHJMLaOo9a7gthilUBGrg2RR cxql1IJDnehJaQIB3nlO1S591IK8nQOTaMgogkDwOLiPo6nwB5MxNFDvunrjBUoZZ7WS vM4R5KiZ0VTYLNT9iCsWLaiNONatawvF7HrUY5VA91MVHi/Q9qrCl0KDO5xwBNBi54fk QaLMTtiXQJ5tuPVU2F6/mBrvPjVr93JhINp1vaiQ7fk0P8lze1C3zJAZACJSQP7lK3zK QbGbumC26pDAqP0uS3gO5f1CnRR87pgfjl4AuchVl5q1Ql6hHPKS11jgxtxlJNaTW4u5 DZxQ== X-Gm-Message-State: ABuFfogcPawbxZroVfAGFgQpYNoc+jQABJ7w8b7eVJaUfC3WyJ5EScPd Dt41Be/79BxqstvkusRJg4lmYXWEx1M= X-Google-Smtp-Source: ACcGV62fQwn6btLZXgIuPYAgAUUjT1D+Ga3c/TBRXnnbKg3s+ye5sxFlTPQ+MLjlb8p/ndYwiyCsnQ== X-Received: by 2002:adf:9244:: with SMTP id 62-v6mr757724wrj.130.1538038257358; Thu, 27 Sep 2018 01:50:57 -0700 (PDT) Received: from rev03.home ([2a01:cb1d:112:6f00:546e:3c44:5966:2f5e]) by smtp.gmail.com with ESMTPSA id p11-v6sm1304055wrd.74.2018.09.27.01.50.55 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 27 Sep 2018 01:50:56 -0700 (PDT) From: Ard Biesheuvel To: linux-kernel@vger.kernel.org, Ingo Molnar , Thomas Gleixner Cc: Ard Biesheuvel , linux-efi@vger.kernel.org, Aaron Ma , Alistair Strachan , Ben Hutchings , Bhupesh Sharma , Hans de Goede , Ivan Hu , Jeremy Linton , Marc Zyngier , Matt Fleming , Peter Robinson , Sai Praneeth Prakhya , Sebastian Andrzej Siewior , Stefan Agner Subject: [PATCH 01/11] efi: honour memory reservations passed via a linux specific config table Date: Thu, 27 Sep 2018 10:50:28 +0200 Message-Id: <20180927085039.8391-2-ard.biesheuvel@linaro.org> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20180927085039.8391-1-ard.biesheuvel@linaro.org> References: <20180927085039.8391-1-ard.biesheuvel@linaro.org> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In order to allow the OS to reserve memory persistently across a kexec, introduce a Linux-specific UEFI configuration table that points to the head of a linked list in memory, allowing each kernel to add list items describing memory regions that the next kernel should treat as reserved. This is useful, e.g., for GICv3 based ARM systems that cannot disable DMA access to the LPI tables, forcing them to reuse the same memory region again after a kexec reboot. Tested-by: Jeremy Linton Signed-off-by: Ard Biesheuvel --- drivers/firmware/efi/efi.c | 27 ++++++++++++++++++++++++++- include/linux/efi.h | 8 ++++++++ 2 files changed, 34 insertions(+), 1 deletion(-) diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c index 2a29dd9c986d..688132ac8a0a 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -52,7 +52,8 @@ struct efi __read_mostly efi = { .properties_table = EFI_INVALID_TABLE_ADDR, .mem_attr_table = EFI_INVALID_TABLE_ADDR, .rng_seed = EFI_INVALID_TABLE_ADDR, - .tpm_log = EFI_INVALID_TABLE_ADDR + .tpm_log = EFI_INVALID_TABLE_ADDR, + .mem_reserve = EFI_INVALID_TABLE_ADDR, }; EXPORT_SYMBOL(efi); @@ -484,6 +485,7 @@ static __initdata efi_config_table_type_t common_tables[] = { {EFI_MEMORY_ATTRIBUTES_TABLE_GUID, "MEMATTR", &efi.mem_attr_table}, {LINUX_EFI_RANDOM_SEED_TABLE_GUID, "RNG", &efi.rng_seed}, {LINUX_EFI_TPM_EVENT_LOG_GUID, "TPMEventLog", &efi.tpm_log}, + {LINUX_EFI_MEMRESERVE_TABLE_GUID, "MEMRESERVE", &efi.mem_reserve}, {NULL_GUID, NULL, NULL}, }; @@ -591,6 +593,29 @@ int __init efi_config_parse_tables(void *config_tables, int count, int sz, early_memunmap(tbl, sizeof(*tbl)); } + if (efi.mem_reserve != EFI_INVALID_TABLE_ADDR) { + unsigned long prsv = efi.mem_reserve; + + while (prsv) { + struct linux_efi_memreserve *rsv; + + /* reserve the entry itself */ + memblock_reserve(prsv, sizeof(*rsv)); + + rsv = early_memremap(prsv, sizeof(*rsv)); + if (rsv == NULL) { + pr_err("Could not map UEFI memreserve entry!\n"); + return -ENOMEM; + } + + if (rsv->size) + memblock_reserve(rsv->base, rsv->size); + + prsv = rsv->next; + early_memunmap(rsv, sizeof(*rsv)); + } + } + return 0; } diff --git a/include/linux/efi.h b/include/linux/efi.h index 401e4b254e30..a5cb580472c5 100644 --- a/include/linux/efi.h +++ b/include/linux/efi.h @@ -672,6 +672,7 @@ void efi_native_runtime_setup(void); #define LINUX_EFI_LOADER_ENTRY_GUID EFI_GUID(0x4a67b082, 0x0a4c, 0x41cf, 0xb6, 0xc7, 0x44, 0x0b, 0x29, 0xbb, 0x8c, 0x4f) #define LINUX_EFI_RANDOM_SEED_TABLE_GUID EFI_GUID(0x1ce1e5bc, 0x7ceb, 0x42f2, 0x81, 0xe5, 0x8a, 0xad, 0xf1, 0x80, 0xf5, 0x7b) #define LINUX_EFI_TPM_EVENT_LOG_GUID EFI_GUID(0xb7799cb0, 0xeca2, 0x4943, 0x96, 0x67, 0x1f, 0xae, 0x07, 0xb7, 0x47, 0xfa) +#define LINUX_EFI_MEMRESERVE_TABLE_GUID EFI_GUID(0x888eb0c6, 0x8ede, 0x4ff5, 0xa8, 0xf0, 0x9a, 0xee, 0x5c, 0xb9, 0x77, 0xc2) typedef struct { efi_guid_t guid; @@ -957,6 +958,7 @@ extern struct efi { unsigned long mem_attr_table; /* memory attributes table */ unsigned long rng_seed; /* UEFI firmware random seed */ unsigned long tpm_log; /* TPM2 Event Log table */ + unsigned long mem_reserve; /* Linux EFI memreserve table */ efi_get_time_t *get_time; efi_set_time_t *set_time; efi_get_wakeup_time_t *get_wakeup_time; @@ -1662,4 +1664,10 @@ extern int efi_tpm_eventlog_init(void); /* Workqueue to queue EFI Runtime Services */ extern struct workqueue_struct *efi_rts_wq; +struct linux_efi_memreserve { + phys_addr_t next; + phys_addr_t base; + phys_addr_t size; +}; + #endif /* _LINUX_EFI_H */ -- 2.18.0