From patchwork Fri Jan 3 11:39:42 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ard Biesheuvel X-Patchwork-Id: 206663 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=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 A82ACC2D0C2 for ; Fri, 3 Jan 2020 11:40:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7E77621D7D for ; Fri, 3 Jan 2020 11:40:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1578051637; bh=ZGdQNY/m9AfSk+pXTJniPsz4ZCTpoChydYzo6TM28KQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=msX5MnHeJiSKKAO1tnIN5Dj5gkG8sx/l/V3ObeWnaBRSOQVyIvAxTWLTr/+sz9HJX yONACGcd3EI+p5nE5d/Cm2DYrQHgrQOisIP9J/OrslVQw6eghIhyDyXBT8SbFJbZNc sX6ceCrgaW3ddSo6g+RcYs8jdnmus5Iq8u8x0olM= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727806AbgACLkh (ORCPT ); Fri, 3 Jan 2020 06:40:37 -0500 Received: from mail.kernel.org ([198.145.29.99]:40102 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727777AbgACLkg (ORCPT ); Fri, 3 Jan 2020 06:40:36 -0500 Received: from localhost.localdomain (amontpellier-657-1-18-247.w109-210.abo.wanadoo.fr [109.210.65.247]) (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 DC7D724655; Fri, 3 Jan 2020 11:40:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1578051634; bh=ZGdQNY/m9AfSk+pXTJniPsz4ZCTpoChydYzo6TM28KQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=JqXIcsleGh1sbnbDc6Z4fIuKO8/sF2C2TAlz4pOeLhhAx7xe0YnY/z4OYY0RSPgKR o9HpyPnt4tnC97qyji0nd35rpGxKuN9IMEAb4I8pgVcfc6Nh1LC3MJA2v+AEB0AOJk DfY/pzxthR/v3enCi56nZsPuT2IaV1YCUTjrkGak= From: Ard Biesheuvel To: linux-efi@vger.kernel.org, Ingo Molnar , Thomas Gleixner Cc: Ard Biesheuvel , Ard Biesheuvel , linux-kernel@vger.kernel.org, Andy Lutomirski , Arvind Sankar , Matthew Garrett Subject: [PATCH 09/20] efi/x86: simplify 64-bit EFI firmware call wrapper Date: Fri, 3 Jan 2020 12:39:42 +0100 Message-Id: <20200103113953.9571-10-ardb@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200103113953.9571-1-ardb@kernel.org> References: <20200103113953.9571-1-ardb@kernel.org> MIME-Version: 1.0 Sender: linux-efi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-efi@vger.kernel.org The efi_call() wrapper used to invoke EFI runtime services serves a number of purposes: - realign the stack to 16 bytes - preserve FP and CR0 register state - translate from SysV to MS calling convention. Preserving CR0.TS is no longer necessary in Linux, and preserving the FP register state is also redundant in most cases, since efi_call() is almost always used from within the scope of a pair of kernel_fpu_begin()/ kernel_fpu_end() calls, with the exception of the early call to SetVirtualAddressMap() and the SGI UV support code. So let's add a pair of kernel_fpu_begin()/_end() calls there as well, and remove the unnecessary code from the assembly implementation of efi_call(), and only keep the pieces that deal with the stack alignment and the ABI translation. Signed-off-by: Ard Biesheuvel --- arch/x86/platform/efi/Makefile | 1 - arch/x86/platform/efi/efi_64.c | 3 +++ arch/x86/platform/efi/efi_stub_64.S | 39 +++-------------------------- arch/x86/platform/uv/bios_uv.c | 7 ++++-- 4 files changed, 12 insertions(+), 38 deletions(-) diff --git a/arch/x86/platform/efi/Makefile b/arch/x86/platform/efi/Makefile index fe29f3f5d384..7ec3a8b31f8b 100644 --- a/arch/x86/platform/efi/Makefile +++ b/arch/x86/platform/efi/Makefile @@ -1,6 +1,5 @@ # SPDX-License-Identifier: GPL-2.0 OBJECT_FILES_NON_STANDARD_efi_thunk_$(BITS).o := y -OBJECT_FILES_NON_STANDARD_efi_stub_$(BITS).o := y obj-$(CONFIG_EFI) += quirks.o efi.o efi_$(BITS).o efi_stub_$(BITS).o obj-$(CONFIG_EFI_MIXED) += efi_thunk_$(BITS).o diff --git a/arch/x86/platform/efi/efi_64.c b/arch/x86/platform/efi/efi_64.c index a7f11d1ff7c4..03565dad0c4b 100644 --- a/arch/x86/platform/efi/efi_64.c +++ b/arch/x86/platform/efi/efi_64.c @@ -1019,6 +1019,8 @@ efi_status_t __init efi_set_virtual_address_map(unsigned long memory_map_size, efi_switch_mm(&efi_mm); } + kernel_fpu_begin(); + /* Disable interrupts around EFI calls: */ local_irq_save(flags); status = efi_call(efi.systab->runtime->set_virtual_address_map, @@ -1026,6 +1028,7 @@ efi_status_t __init efi_set_virtual_address_map(unsigned long memory_map_size, descriptor_version, virtual_map); local_irq_restore(flags); + kernel_fpu_end(); if (save_pgd) efi_old_memmap_phys_epilog(save_pgd); diff --git a/arch/x86/platform/efi/efi_stub_64.S b/arch/x86/platform/efi/efi_stub_64.S index b1d2313fe3bf..e7e1020f4ccb 100644 --- a/arch/x86/platform/efi/efi_stub_64.S +++ b/arch/x86/platform/efi/efi_stub_64.S @@ -8,41 +8,12 @@ */ #include -#include -#include -#include -#include - -#define SAVE_XMM \ - mov %rsp, %rax; \ - subq $0x70, %rsp; \ - and $~0xf, %rsp; \ - mov %rax, (%rsp); \ - mov %cr0, %rax; \ - clts; \ - mov %rax, 0x8(%rsp); \ - movaps %xmm0, 0x60(%rsp); \ - movaps %xmm1, 0x50(%rsp); \ - movaps %xmm2, 0x40(%rsp); \ - movaps %xmm3, 0x30(%rsp); \ - movaps %xmm4, 0x20(%rsp); \ - movaps %xmm5, 0x10(%rsp) - -#define RESTORE_XMM \ - movaps 0x60(%rsp), %xmm0; \ - movaps 0x50(%rsp), %xmm1; \ - movaps 0x40(%rsp), %xmm2; \ - movaps 0x30(%rsp), %xmm3; \ - movaps 0x20(%rsp), %xmm4; \ - movaps 0x10(%rsp), %xmm5; \ - mov 0x8(%rsp), %rsi; \ - mov %rsi, %cr0; \ - mov (%rsp), %rsp +#include SYM_FUNC_START(efi_call) pushq %rbp movq %rsp, %rbp - SAVE_XMM + and $~0xf, %rsp mov 16(%rbp), %rax subq $48, %rsp mov %r9, 32(%rsp) @@ -50,9 +21,7 @@ SYM_FUNC_START(efi_call) mov %r8, %r9 mov %rcx, %r8 mov %rsi, %rcx - call *%rdi - addq $48, %rsp - RESTORE_XMM - popq %rbp + CALL_NOSPEC %rdi + leave ret SYM_FUNC_END(efi_call) diff --git a/arch/x86/platform/uv/bios_uv.c b/arch/x86/platform/uv/bios_uv.c index ece9cb9c1189..5c0e2eb5d87c 100644 --- a/arch/x86/platform/uv/bios_uv.c +++ b/arch/x86/platform/uv/bios_uv.c @@ -34,10 +34,13 @@ static s64 __uv_bios_call(enum uv_bios_cmd which, u64 a1, u64 a2, u64 a3, * If EFI_OLD_MEMMAP is set, we need to fall back to using our old EFI * callback method, which uses efi_call() directly, with the kernel page tables: */ - if (unlikely(efi_enabled(EFI_OLD_MEMMAP))) + if (unlikely(efi_enabled(EFI_OLD_MEMMAP))) { + kernel_fpu_begin(); ret = efi_call((void *)__va(tab->function), (u64)which, a1, a2, a3, a4, a5); - else + kernel_fpu_end(); + } else { ret = efi_call_virt_pointer(tab, function, (u64)which, a1, a2, a3, a4, a5); + } return ret; }