From patchwork Mon Aug 7 16:27:12 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ard Biesheuvel X-Patchwork-Id: 711358 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B3C84C04FDF for ; Mon, 7 Aug 2023 16:28:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231177AbjHGQ2v (ORCPT ); Mon, 7 Aug 2023 12:28:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34852 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231633AbjHGQ22 (ORCPT ); Mon, 7 Aug 2023 12:28:28 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B34A8173D; Mon, 7 Aug 2023 09:28:13 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 89C1661F1A; Mon, 7 Aug 2023 16:28:13 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 483E1C433C7; Mon, 7 Aug 2023 16:28:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1691425693; bh=sWc7DHFUuLP6QmqVwRrlrkEzojfIVsiaqVuAFFfb3sc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=TQjDxWVw0/rbXcPjW+8tukazzMMDjTVwzBXtub4M8wBI1vPjMy1UJOPxGtLxGNSDY FXKUX1d+kyET4PwNEE3caU11xor0tlK3qwU2Natn83DaJ0ivKJBDovcKmiQrgs91Jp WHslVE+sNvV+Rdl96xKKfmvu/8RYqVSDd3BAYrWpn2ZuGq3KkZ9F9tiaYzVYPEs9Iy ODQW5Rkv0DnFtA2HkJfvhFcZeMlvn1z1aDtxMYSLWutvrrGh3KpjEDclmGAamWp3bA wWnFgy3rN1DhMZwwKGfO+hkdbKYxxx64JpBKTSo9o3LlglP1i4dTtX5rEf7z/a5Gdl oUINUUmM22f3g== From: Ard Biesheuvel To: linux-efi@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Ard Biesheuvel , Borislav Petkov , Dave Hansen , Ingo Molnar , Thomas Gleixner , "Kirill A . Shutemov" Subject: [PATCH v9 15/23] x86/decompressor: Merge trampoline cleanup with switching code Date: Mon, 7 Aug 2023 18:27:12 +0200 Message-Id: <20230807162720.545787-16-ardb@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230807162720.545787-1-ardb@kernel.org> References: <20230807162720.545787-1-ardb@kernel.org> MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=2924; i=ardb@kernel.org; h=from:subject; bh=sWc7DHFUuLP6QmqVwRrlrkEzojfIVsiaqVuAFFfb3sc=; b=owGbwMvMwCFmkMcZplerG8N4Wi2JIeWidKzLY8klZ+qqvywtXlFyUuf+4er5Z8tOWr1hWtHt0 hy2YNGOjlIWBjEOBlkxRRaB2X/f7Tw9UarWeZYszBxWJpAhDFycAjCRj6WMDG/DQ47eFVmgu/WX D3vtpLnRbv5RBvvuC/ouVj6y6s/Hl8UM/wMz+V+FOz86w93cdKpi05cmf06m0oPySleibFeFijd OYQYA X-Developer-Key: i=ardb@kernel.org; a=openpgp; fpr=F43D03328115A198C90016883D200E9CA6329909 Precedence: bulk List-ID: X-Mailing-List: linux-efi@vger.kernel.org Now that the trampoline setup code and the actual invocation of it are all done from the C routine, the trampoline cleanup can be merged into it as well, instead of returning to asm just to call another C function. Acked-by: Kirill A. Shutemov Signed-off-by: Ard Biesheuvel --- arch/x86/boot/compressed/head_64.S | 14 ++++---------- arch/x86/boot/compressed/pgtable_64.c | 18 ++++-------------- 2 files changed, 8 insertions(+), 24 deletions(-) diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S index afdaf8cb8bb98694..fb0e562c26f64c9c 100644 --- a/arch/x86/boot/compressed/head_64.S +++ b/arch/x86/boot/compressed/head_64.S @@ -430,20 +430,14 @@ SYM_CODE_START(startup_64) * a trampoline in 32-bit addressable memory if the current number does * not match the desired number. * - * Pass the boot_params pointer as the first argument. + * Pass the boot_params pointer as the first argument. The second + * argument is the relocated address of the page table to use instead + * of the page table in trampoline memory (if required). */ movq %r15, %rdi + leaq rva(top_pgtable)(%rbx), %rsi call configure_5level_paging - /* - * cleanup_trampoline() would restore trampoline memory. - * - * RDI is address of the page table to use instead of page table - * in trampoline memory (if required). - */ - leaq rva(top_pgtable)(%rbx), %rdi - call cleanup_trampoline - /* Zero EFLAGS */ pushq $0 popfq diff --git a/arch/x86/boot/compressed/pgtable_64.c b/arch/x86/boot/compressed/pgtable_64.c index eab4e6b568ae05c4..7939eb6e6ce9bb01 100644 --- a/arch/x86/boot/compressed/pgtable_64.c +++ b/arch/x86/boot/compressed/pgtable_64.c @@ -101,7 +101,7 @@ static unsigned long find_trampoline_placement(void) return bios_start - TRAMPOLINE_32BIT_SIZE; } -asmlinkage void configure_5level_paging(struct boot_params *bp) +asmlinkage void configure_5level_paging(struct boot_params *bp, void *pgtable) { void (*toggle_la57)(void *cr3); bool l5_required = false; @@ -191,22 +191,12 @@ asmlinkage void configure_5level_paging(struct boot_params *bp) } toggle_la57(trampoline_32bit); -} - -void cleanup_trampoline(void *pgtable) -{ - void *trampoline_pgtable; - - trampoline_pgtable = trampoline_32bit; /* - * Move the top level page table out of trampoline memory, - * if it's there. + * Move the top level page table out of trampoline memory. */ - if ((void *)__native_read_cr3() == trampoline_pgtable) { - memcpy(pgtable, trampoline_pgtable, PAGE_SIZE); - native_write_cr3((unsigned long)pgtable); - } + memcpy(pgtable, trampoline_32bit, PAGE_SIZE); + native_write_cr3((unsigned long)pgtable); /* Restore trampoline memory */ memcpy(trampoline_32bit, trampoline_save, TRAMPOLINE_32BIT_SIZE);