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=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 A4FF2C2D0DA for ; Thu, 26 Dec 2019 15:16:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7B8C52075E for ; Thu, 26 Dec 2019 15:16:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1577373407; bh=NGZhSFbOjCSMCE5gB6MC1CF7f/JFdBAw1Ou3iXbWcOA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=YIHwgh5RdinrRFPcGDPraolM7Qb7hWjCBkw1WOxq4otFYawtDddBTrabyaBk4WKSK JvlDgp8yfNRlnWTlA/mxjgchEuQj49h/EKRYUGecmfR1GsyQFaZpffcycKsiKZwnc1 Qsr3lEwV4SbZ7t1Hw823oWrWabASeKjAmn8ZvWvc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726453AbfLZPQr (ORCPT ); Thu, 26 Dec 2019 10:16:47 -0500 Received: from mail.kernel.org ([198.145.29.99]:34214 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726450AbfLZPQq (ORCPT ); Thu, 26 Dec 2019 10:16:46 -0500 Received: from e123331-lin.home (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 D466A20882; Thu, 26 Dec 2019 15:16:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1577373406; bh=NGZhSFbOjCSMCE5gB6MC1CF7f/JFdBAw1Ou3iXbWcOA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=HFCxGxVh8J2agBqMCFEIn04cEG16u+BlDRRsV1YH1wY7F37R03M1MBrlOu++e81gK INzkhrE8Tsz5D4lxCH7syi+h5J0jQlOEoEus09SoLzzkhEq98n0L5tSU9SwfM/VKaN 4PdAM9fxKvXmQVai1YDy6mQhgDcFAU3B64mML9Cg= From: Ard Biesheuvel To: linux-efi@vger.kernel.org Cc: nivedita@alum.mit.edu, hdegoede@redhat.com, Ard Biesheuvel , Andy Lutomirski , Ingo Molnar Subject: [PATCH 1/3] efi/x86: simplify 64-bit EFI firmware call wrapper Date: Thu, 26 Dec 2019 16:14:05 +0100 Message-Id: <20191226151407.29716-2-ardb@kernel.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20191226151407.29716-1-ardb@kernel.org> References: <20191226151407.29716-1-ardb@kernel.org> 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 register state - translate from SysV to MS calling convention. Preserving the FP register state is redundant in most cases, since efi_call() is almost always used from within the scope of a pair of kernel_fpu_begin()/_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/efi_64.c | 4 +++ arch/x86/platform/efi/efi_stub_64.S | 36 ++------------------ arch/x86/platform/uv/bios_uv.c | 7 ++-- 3 files changed, 11 insertions(+), 36 deletions(-) diff --git a/arch/x86/platform/efi/efi_64.c b/arch/x86/platform/efi/efi_64.c index 03c2ed3c645c..3690df1d31c6 100644 --- a/arch/x86/platform/efi/efi_64.c +++ b/arch/x86/platform/efi/efi_64.c @@ -84,6 +84,7 @@ pgd_t * __init efi_call_phys_prolog(void) if (!efi_enabled(EFI_OLD_MEMMAP)) { efi_switch_mm(&efi_mm); + kernel_fpu_begin(); return efi_mm.pgd; } @@ -141,6 +142,7 @@ pgd_t * __init efi_call_phys_prolog(void) } __flush_tlb_all(); + kernel_fpu_begin(); return save_pgd; out: efi_call_phys_epilog(save_pgd); @@ -158,6 +160,8 @@ void __init efi_call_phys_epilog(pgd_t *save_pgd) p4d_t *p4d; pud_t *pud; + kernel_fpu_end(); + if (!efi_enabled(EFI_OLD_MEMMAP)) { efi_switch_mm(efi_scratch.prev_mm); return; diff --git a/arch/x86/platform/efi/efi_stub_64.S b/arch/x86/platform/efi/efi_stub_64.S index b1d2313fe3bf..3e44d55ac730 100644 --- a/arch/x86/platform/efi/efi_stub_64.S +++ b/arch/x86/platform/efi/efi_stub_64.S @@ -8,41 +8,11 @@ */ #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 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) @@ -51,8 +21,6 @@ SYM_FUNC_START(efi_call) mov %rcx, %r8 mov %rsi, %rcx call *%rdi - addq $48, %rsp - RESTORE_XMM - popq %rbp + 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; } -- 2.17.1