From patchwork Fri May 13 14:23:45 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 572512 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 CBC8BC433F5 for ; Fri, 13 May 2022 14:31:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1380918AbiEMObj (ORCPT ); Fri, 13 May 2022 10:31:39 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46534 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1381398AbiEMObW (ORCPT ); Fri, 13 May 2022 10:31:22 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 450701A7D02; Fri, 13 May 2022 07:29:04 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id C6912621A9; Fri, 13 May 2022 14:29:03 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id BE5F1C34100; Fri, 13 May 2022 14:29:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1652452143; bh=eV4ZT1JHdZBrwzJ4fhmScpaWEESNg35gtavKqTCc4ao=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=KxdA7JqrWZXBnYjmzDFjNemgl+9Q/AQ86s1RKIAK8HjivC2xMqQhN0UGOF5tEpKtj kxlsn8sJrRtHTeGeC+cxOHOm5uM8NQHL/et7XBeXyvahawHlCXEvEYT2PJkTNANi4b IB+puHV9RlkDrGmq+lP5Ygodgxjpm1aiFjppvEXQ= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "Peter Zijlstra (Intel)" , Borislav Petkov , Sasha Levin Subject: [PATCH 5.15 03/21] x86: Prepare inline-asm for straight-line-speculation Date: Fri, 13 May 2022 16:23:45 +0200 Message-Id: <20220513142229.978979020@linuxfoundation.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220513142229.874949670@linuxfoundation.org> References: <20220513142229.874949670@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Peter Zijlstra [ Upstream commit b17c2baa305cccbd16bafa289fd743cc2db77966 ] Replace all ret/retq instructions with ASM_RET in preparation of making it more than a single instruction. Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Borislav Petkov Link: https://lore.kernel.org/r/20211204134907.964635458@infradead.org Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- arch/x86/include/asm/linkage.h | 4 ++++ arch/x86/include/asm/paravirt.h | 2 +- arch/x86/include/asm/qspinlock_paravirt.h | 4 ++-- arch/x86/kernel/alternative.c | 2 +- arch/x86/kernel/kprobes/core.c | 2 +- arch/x86/kernel/paravirt.c | 2 +- arch/x86/kvm/emulate.c | 4 ++-- arch/x86/lib/error-inject.c | 3 ++- samples/ftrace/ftrace-direct-modify.c | 4 ++-- samples/ftrace/ftrace-direct-too.c | 2 +- samples/ftrace/ftrace-direct.c | 2 +- 11 files changed, 18 insertions(+), 13 deletions(-) --- a/arch/x86/include/asm/linkage.h +++ b/arch/x86/include/asm/linkage.h @@ -18,6 +18,10 @@ #define __ALIGN_STR __stringify(__ALIGN) #endif +#else /* __ASSEMBLY__ */ + +#define ASM_RET "ret\n\t" + #endif /* __ASSEMBLY__ */ #endif /* _ASM_X86_LINKAGE_H */ --- a/arch/x86/include/asm/paravirt.h +++ b/arch/x86/include/asm/paravirt.h @@ -665,7 +665,7 @@ bool __raw_callee_save___native_vcpu_is_ "call " #func ";" \ PV_RESTORE_ALL_CALLER_REGS \ FRAME_END \ - "ret;" \ + ASM_RET \ ".size " PV_THUNK_NAME(func) ", .-" PV_THUNK_NAME(func) ";" \ ".popsection") --- a/arch/x86/include/asm/qspinlock_paravirt.h +++ b/arch/x86/include/asm/qspinlock_paravirt.h @@ -48,7 +48,7 @@ asm (".pushsection .text;" "jne .slowpath;" "pop %rdx;" FRAME_END - "ret;" + ASM_RET ".slowpath: " "push %rsi;" "movzbl %al,%esi;" @@ -56,7 +56,7 @@ asm (".pushsection .text;" "pop %rsi;" "pop %rdx;" FRAME_END - "ret;" + ASM_RET ".size " PV_UNLOCK ", .-" PV_UNLOCK ";" ".popsection"); --- a/arch/x86/kernel/alternative.c +++ b/arch/x86/kernel/alternative.c @@ -537,7 +537,7 @@ asm ( " .type int3_magic, @function\n" "int3_magic:\n" " movl $1, (%" _ASM_ARG1 ")\n" -" ret\n" + ASM_RET " .size int3_magic, .-int3_magic\n" " .popsection\n" ); --- a/arch/x86/kernel/kprobes/core.c +++ b/arch/x86/kernel/kprobes/core.c @@ -1044,7 +1044,7 @@ asm( RESTORE_REGS_STRING " popfl\n" #endif - " ret\n" + ASM_RET ".size kretprobe_trampoline, .-kretprobe_trampoline\n" ); NOKPROBE_SYMBOL(kretprobe_trampoline); --- a/arch/x86/kernel/paravirt.c +++ b/arch/x86/kernel/paravirt.c @@ -41,7 +41,7 @@ extern void _paravirt_nop(void); asm (".pushsection .entry.text, \"ax\"\n" ".global _paravirt_nop\n" "_paravirt_nop:\n\t" - "ret\n\t" + ASM_RET ".size _paravirt_nop, . - _paravirt_nop\n\t" ".type _paravirt_nop, @function\n\t" ".popsection"); --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -315,7 +315,7 @@ static int fastop(struct x86_emulate_ctx __FOP_FUNC(#name) #define __FOP_RET(name) \ - "ret \n\t" \ + ASM_RET \ ".size " name ", .-" name "\n\t" #define FOP_RET(name) \ @@ -435,7 +435,7 @@ static int fastop(struct x86_emulate_ctx __FOP_RET(#op) asm(".pushsection .fixup, \"ax\"\n" - "kvm_fastop_exception: xor %esi, %esi; ret\n" + "kvm_fastop_exception: xor %esi, %esi; " ASM_RET ".popsection"); FOP_START(setcc) --- a/arch/x86/lib/error-inject.c +++ b/arch/x86/lib/error-inject.c @@ -1,5 +1,6 @@ // SPDX-License-Identifier: GPL-2.0 +#include #include #include @@ -10,7 +11,7 @@ asm( ".type just_return_func, @function\n" ".globl just_return_func\n" "just_return_func:\n" - " ret\n" + ASM_RET ".size just_return_func, .-just_return_func\n" ); --- a/samples/ftrace/ftrace-direct-modify.c +++ b/samples/ftrace/ftrace-direct-modify.c @@ -31,7 +31,7 @@ asm ( " call my_direct_func1\n" " leave\n" " .size my_tramp1, .-my_tramp1\n" -" ret\n" + ASM_RET " .type my_tramp2, @function\n" " .globl my_tramp2\n" " my_tramp2:" @@ -39,7 +39,7 @@ asm ( " movq %rsp, %rbp\n" " call my_direct_func2\n" " leave\n" -" ret\n" + ASM_RET " .size my_tramp2, .-my_tramp2\n" " .popsection\n" ); --- a/samples/ftrace/ftrace-direct-too.c +++ b/samples/ftrace/ftrace-direct-too.c @@ -31,7 +31,7 @@ asm ( " popq %rsi\n" " popq %rdi\n" " leave\n" -" ret\n" + ASM_RET " .size my_tramp, .-my_tramp\n" " .popsection\n" ); --- a/samples/ftrace/ftrace-direct.c +++ b/samples/ftrace/ftrace-direct.c @@ -24,7 +24,7 @@ asm ( " call my_direct_func\n" " popq %rdi\n" " leave\n" -" ret\n" + ASM_RET " .size my_tramp, .-my_tramp\n" " .popsection\n" );