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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 8C279C2BA83 for ; Fri, 14 Feb 2020 16:51:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 663EB2468E for ; Fri, 14 Feb 2020 16:51:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581699103; bh=65POcJFp0QtikRJMJrWeAydJ2XT6KUTDHap55AKMNRs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=SdfDuECNxbiEhVZdDqgGHzF+KgFkUHv9rtF5vE+qRV3vYKcXMiIt+wgZrDcq+8Yg3 rhTfkp8swtbb+JSlSonl/S1x0N1Ctxx0EToFtDEYKebHR8fvhvEPrt0DNbkMnI59i7 EFSI1IZ5T56X1mVW0okyIciyG01/za+Mb4LZLUXU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2405050AbgBNQTn (ORCPT ); Fri, 14 Feb 2020 11:19:43 -0500 Received: from mail.kernel.org ([198.145.29.99]:52872 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2405043AbgBNQTn (ORCPT ); Fri, 14 Feb 2020 11:19:43 -0500 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 2724924716; Fri, 14 Feb 2020 16:19:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581697182; bh=65POcJFp0QtikRJMJrWeAydJ2XT6KUTDHap55AKMNRs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=rx+k4w7I0Z+7zxQ+n6k/6aOk+gLNaktlz5o7VOu2cCDpRyv6xa0IRVkCPxKcHUJz3 WEnBdttp7wF5s4UJ4ykmS1Iy1TW+cmUxy7vdBtvGNGGeb62WPD2dW0BTZUiWx9DH5N mCbn7mfvDOETgqDWmw3mrxVwaBjDLdNOZFxILsj0= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Ard Biesheuvel , Andy Lutomirski , Ard Biesheuvel , Arvind Sankar , Matthew Garrett , linux-efi@vger.kernel.org, Ingo Molnar , Sasha Levin , platform-driver-x86@vger.kernel.org, x86@kernel.org Subject: [PATCH AUTOSEL 4.14 113/186] efi/x86: Don't panic or BUG() on non-critical error conditions Date: Fri, 14 Feb 2020 11:16:02 -0500 Message-Id: <20200214161715.18113-113-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200214161715.18113-1-sashal@kernel.org> References: <20200214161715.18113-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-efi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-efi@vger.kernel.org From: Ard Biesheuvel [ Upstream commit e2d68a955e49d61fd0384f23e92058dc9b79be5e ] The logic in __efi_enter_virtual_mode() does a number of steps in sequence, all of which may fail in one way or the other. In most cases, we simply print an error and disable EFI runtime services support, but in some cases, we BUG() or panic() and bring down the system when encountering conditions that we could easily handle in the same way. While at it, replace a pointless page-to-virt-phys conversion with one that goes straight from struct page to physical. Signed-off-by: Ard Biesheuvel Cc: Andy Lutomirski Cc: Ard Biesheuvel Cc: Arvind Sankar Cc: Matthew Garrett Cc: linux-efi@vger.kernel.org Link: https://lkml.kernel.org/r/20200103113953.9571-14-ardb@kernel.org Signed-off-by: Ingo Molnar Signed-off-by: Sasha Levin --- arch/x86/platform/efi/efi.c | 28 ++++++++++++++-------------- arch/x86/platform/efi/efi_64.c | 9 +++++---- 2 files changed, 19 insertions(+), 18 deletions(-) diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c index 5b0275310070e..e7f19dec16b97 100644 --- a/arch/x86/platform/efi/efi.c +++ b/arch/x86/platform/efi/efi.c @@ -930,16 +930,14 @@ static void __init __efi_enter_virtual_mode(void) if (efi_alloc_page_tables()) { pr_err("Failed to allocate EFI page tables\n"); - clear_bit(EFI_RUNTIME_SERVICES, &efi.flags); - return; + goto err; } efi_merge_regions(); new_memmap = efi_map_regions(&count, &pg_shift); if (!new_memmap) { pr_err("Error reallocating memory, EFI runtime non-functional!\n"); - clear_bit(EFI_RUNTIME_SERVICES, &efi.flags); - return; + goto err; } pa = __pa(new_memmap); @@ -953,8 +951,7 @@ static void __init __efi_enter_virtual_mode(void) if (efi_memmap_init_late(pa, efi.memmap.desc_size * count)) { pr_err("Failed to remap late EFI memory map\n"); - clear_bit(EFI_RUNTIME_SERVICES, &efi.flags); - return; + goto err; } if (efi_enabled(EFI_DBG)) { @@ -962,12 +959,11 @@ static void __init __efi_enter_virtual_mode(void) efi_print_memmap(); } - BUG_ON(!efi.systab); + if (WARN_ON(!efi.systab)) + goto err; - if (efi_setup_page_tables(pa, 1 << pg_shift)) { - clear_bit(EFI_RUNTIME_SERVICES, &efi.flags); - return; - } + if (efi_setup_page_tables(pa, 1 << pg_shift)) + goto err; efi_sync_low_kernel_mappings(); @@ -987,9 +983,9 @@ static void __init __efi_enter_virtual_mode(void) } if (status != EFI_SUCCESS) { - pr_alert("Unable to switch EFI into virtual mode (status=%lx)!\n", - status); - panic("EFI call to SetVirtualAddressMap() failed!"); + pr_err("Unable to switch EFI into virtual mode (status=%lx)!\n", + status); + goto err; } /* @@ -1016,6 +1012,10 @@ static void __init __efi_enter_virtual_mode(void) /* clean DUMMY object */ efi_delete_dummy_variable(); + return; + +err: + clear_bit(EFI_RUNTIME_SERVICES, &efi.flags); } void __init efi_enter_virtual_mode(void) diff --git a/arch/x86/platform/efi/efi_64.c b/arch/x86/platform/efi/efi_64.c index ae369c2bbc3eb..0ebb7f94fd518 100644 --- a/arch/x86/platform/efi/efi_64.c +++ b/arch/x86/platform/efi/efi_64.c @@ -390,11 +390,12 @@ int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages) return 0; page = alloc_page(GFP_KERNEL|__GFP_DMA32); - if (!page) - panic("Unable to allocate EFI runtime stack < 4GB\n"); + if (!page) { + pr_err("Unable to allocate EFI runtime stack < 4GB\n"); + return 1; + } - efi_scratch.phys_stack = virt_to_phys(page_address(page)); - efi_scratch.phys_stack += PAGE_SIZE; /* stack grows down */ + efi_scratch.phys_stack = page_to_phys(page + 1); /* stack grows down */ npages = (_etext - _text) >> PAGE_SHIFT; text = __pa(_text); -- 2.20.1