From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from theia.8bytes.org (8bytes.org [81.169.241.247]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3D9752FB1 for ; Tue, 8 Jun 2021 09:54:52 +0000 (UTC) Received: from cap.home.8bytes.org (p4ff2ba7c.dip0.t-ipconnect.de [79.242.186.124]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 91B0A386; Tue, 8 Jun 2021 11:54:44 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , Tom Lendacky , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , Arvind Sankar , linux-coco@lists.linux.dev, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v3 1/7] x86/ioremap: Map efi_mem_reserve() memory as encrypted for SEV Date: Tue, 8 Jun 2021 11:54:33 +0200 Message-Id: <20210608095439.12668-2-joro@8bytes.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210608095439.12668-1-joro@8bytes.org> References: <20210608095439.12668-1-joro@8bytes.org> X-Mailing-List: linux-coco@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Tom Lendacky Some drivers require memory that is marked as EFI boot services data. So that this memory is not re-used by the kernel after ExitBootServices(), efi_mem_reserve() is used to preserve it by inserting a new EFI memory descriptor and marking it with the EFI_MEMORY_RUNTIME attribute. Under SEV, memory marked with the EFI_MEMORY_RUNTIME attribute needs to be mapped encrypted by Linux, otherwise the kernel might crash at boot like below: EFI Variables Facility v0.08 2004-May-17 general protection fault, probably for non-canonical address 0x3597688770a868b2: 0000 [#1] SMP NOPTI CPU: 13 PID: 1 Comm: swapper/0 Not tainted 5.12.4-2-default #1 openSUSE Tumbleweed Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 RIP: 0010:efi_mokvar_entry_next+0x34/0x40 Code: c5 01 48 8b 17 48 c7 07 00 00 00 00 48 85 c0 74 24 48 85 d2 74 14 80 3a 00 74 18 48 8b 82 00 01 00 00 48 8d 84 02 08 01 00 00 <80> 38 00 74 04 48 89 07 c3 31 c0 c3 0f 1f 44 00 00 41 54 4c 8b 25 [...] Call Trace: efi_mokvar_sysfs_init ? efi_mokvar_table_init do_one_initcall ? __kmalloc kernel_init_freeable ? rest_init kernel_init ret_from_fork Modules linked in: ---[ end trace 0de27ecc25d41b73 ]--- Expand the __ioremap_check_other() function to additionally check for this other type of "runtime" data and indicate that it should be mapped encrypted for an SEV guest. Fixes: 58c909022a5a ("efi: Support for MOK variable config table") Reported-by: Joerg Roedel Tested-by: Joerg Roedel Signed-off-by: Tom Lendacky Signed-off-by: Joerg Roedel --- arch/x86/mm/ioremap.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c index 12c686c65ea9..60ade7dd71bd 100644 --- a/arch/x86/mm/ioremap.c +++ b/arch/x86/mm/ioremap.c @@ -118,7 +118,9 @@ static void __ioremap_check_other(resource_size_t addr, struct ioremap_desc *des if (!IS_ENABLED(CONFIG_EFI)) return; - if (efi_mem_type(addr) == EFI_RUNTIME_SERVICES_DATA) + if (efi_mem_type(addr) == EFI_RUNTIME_SERVICES_DATA || + (efi_mem_type(addr) == EFI_BOOT_SERVICES_DATA && + efi_mem_attributes(addr) & EFI_MEMORY_RUNTIME)) desc->flags |= IORES_MAP_ENCRYPTED; } -- 2.31.1