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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1AF02C433FE for ; Mon, 17 Oct 2022 14:59:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231542AbiJQO7Q (ORCPT ); Mon, 17 Oct 2022 10:59:16 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59658 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231279AbiJQO6I (ORCPT ); Mon, 17 Oct 2022 10:58:08 -0400 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C029E6AEA0; Mon, 17 Oct 2022 07:55:29 -0700 (PDT) Date: Mon, 17 Oct 2022 14:54:24 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1666018465; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=QRRzc0lJSGyWmsjfsGEGJxK5nMKStNTxv/6FkpgUndU=; b=HeP1Ey5vaQJPQG0FKogEwKtOCvi+rfK5HWX5nkLMt4qKiYdqzrOnnoYgTtH7/vhkDMgzPT 2hPQD0/w/UT46aSjXdzY3WDhe9Ch3uYsO+ne8fgy9bdl+s9/32/eewqFEnax+XyWat3p7L 8rBle46P5ytY9sN5sV3JWqqbfHv4uk0aLEVDjBKY5Jl1ajWSyxj/r+ULPiwFXLfBdgEdxf FVP2I+BfKK8r2/QDx8Xzl15hz72BlljcgyknrDLxw0/8nWaHQ4WTxLgjvlPnPLRRTmKOtd L8RySDFJtkObWmyuJ2ZkRZ26AMwwvTa29P/LL0IHFZ4VOelPAKCx8ZZuy2Ee1g== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1666018465; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=QRRzc0lJSGyWmsjfsGEGJxK5nMKStNTxv/6FkpgUndU=; b=Ncl04xEz7lGeRLkdnJGNkl1lyPwABrJS1bA29XmgYribUvei8RmcOX4/WZ4YdO33DBgxKa hYjfWvuUAK5qhgAQ== From: "tip-bot2 for Peter Zijlstra" Sender: tip-bot2@linutronix.de Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: x86/core] arch: Introduce CONFIG_FUNCTION_ALIGNMENT Cc: "Peter Zijlstra (Intel)" , x86@kernel.org, linux-kernel@vger.kernel.org In-Reply-To: <20220915111143.719248727@infradead.org> References: <20220915111143.719248727@infradead.org> MIME-Version: 1.0 Message-ID: <166601846460.401.3940443761327379184.tip-bot2@tip-bot2> Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The following commit has been merged into the x86/core branch of tip: Commit-ID: d49a0626216b95cd4bf696f6acf55f39a16ab0bb Gitweb: https://git.kernel.org/tip/d49a0626216b95cd4bf696f6acf55f39a16ab0bb Author: Peter Zijlstra AuthorDate: Thu, 15 Sep 2022 13:10:47 +02:00 Committer: Peter Zijlstra CommitterDate: Mon, 17 Oct 2022 16:40:58 +02:00 arch: Introduce CONFIG_FUNCTION_ALIGNMENT Generic function-alignment infrastructure. Architectures can select FUNCTION_ALIGNMENT_xxB symbols; the FUNCTION_ALIGNMENT symbol is then set to the largest such selected size, 0 otherwise. >>From this the -falign-functions compiler argument and __ALIGN macro are set. This incorporates the DEBUG_FORCE_FUNCTION_ALIGN_64B knob and future alignment requirements for x86_64 (later in this series) into a single place. NOTE: also removes the 0x90 filler byte from the generic __ALIGN primitive, that value makes no sense outside of x86. NOTE: .balign 0 reverts to a no-op. Requested-by: Linus Torvalds Signed-off-by: Peter Zijlstra (Intel) Link: https://lore.kernel.org/r/20220915111143.719248727@infradead.org --- Makefile | 4 ++-- arch/Kconfig | 24 ++++++++++++++++++++++++ arch/ia64/Kconfig | 1 + arch/ia64/Makefile | 2 +- arch/x86/Kconfig | 2 ++ arch/x86/boot/compressed/head_64.S | 8 ++++++++ arch/x86/include/asm/linkage.h | 4 +--- include/asm-generic/vmlinux.lds.h | 4 ++-- include/linux/linkage.h | 4 ++-- lib/Kconfig.debug | 1 + 10 files changed, 44 insertions(+), 10 deletions(-) diff --git a/Makefile b/Makefile index f41ec8c..141e1bc 100644 --- a/Makefile +++ b/Makefile @@ -1004,8 +1004,8 @@ KBUILD_CFLAGS += $(CC_FLAGS_CFI) export CC_FLAGS_CFI endif -ifdef CONFIG_DEBUG_FORCE_FUNCTION_ALIGN_64B -KBUILD_CFLAGS += -falign-functions=64 +ifneq ($(CONFIG_FUNCTION_ALIGNMENT),0) +KBUILD_CFLAGS += -falign-functions=$(CONFIG_FUNCTION_ALIGNMENT) endif # arch Makefile may override CC so keep this after arch Makefile is included diff --git a/arch/Kconfig b/arch/Kconfig index 8f138e5..4025802 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -1428,4 +1428,28 @@ source "kernel/gcov/Kconfig" source "scripts/gcc-plugins/Kconfig" +config FUNCTION_ALIGNMENT_4B + bool + +config FUNCTION_ALIGNMENT_8B + bool + +config FUNCTION_ALIGNMENT_16B + bool + +config FUNCTION_ALIGNMENT_32B + bool + +config FUNCTION_ALIGNMENT_64B + bool + +config FUNCTION_ALIGNMENT + int + default 64 if FUNCTION_ALIGNMENT_64B + default 32 if FUNCTION_ALIGNMENT_32B + default 16 if FUNCTION_ALIGNMENT_16B + default 8 if FUNCTION_ALIGNMENT_8B + default 4 if FUNCTION_ALIGNMENT_4B + default 0 + endmenu diff --git a/arch/ia64/Kconfig b/arch/ia64/Kconfig index c6e06cd..d7e4a24 100644 --- a/arch/ia64/Kconfig +++ b/arch/ia64/Kconfig @@ -63,6 +63,7 @@ config IA64 select NUMA if !FLATMEM select PCI_MSI_ARCH_FALLBACKS if PCI_MSI select ZONE_DMA32 + select FUNCTION_ALIGNMENT_32B default y help The Itanium Processor Family is Intel's 64-bit successor to diff --git a/arch/ia64/Makefile b/arch/ia64/Makefile index 56c4bb2..d553ab7 100644 --- a/arch/ia64/Makefile +++ b/arch/ia64/Makefile @@ -23,7 +23,7 @@ KBUILD_AFLAGS_KERNEL := -mconstant-gp EXTRA := cflags-y := -pipe $(EXTRA) -ffixed-r13 -mfixed-range=f12-f15,f32-f127 \ - -falign-functions=32 -frename-registers -fno-optimize-sibling-calls + -frename-registers -fno-optimize-sibling-calls KBUILD_CFLAGS_KERNEL := -mconstant-gp GAS_STATUS = $(shell $(srctree)/arch/ia64/scripts/check-gas "$(CC)" "$(OBJDUMP)") diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 6d1879e..f408fa8 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -290,6 +290,8 @@ config X86 select X86_FEATURE_NAMES if PROC_FS select PROC_PID_ARCH_STATUS if PROC_FS select HAVE_ARCH_NODE_DEV_GROUP if X86_SGX + select FUNCTION_ALIGNMENT_16B if X86_64 || X86_ALIGNMENT_16 + select FUNCTION_ALIGNMENT_4B imply IMA_SECURE_AND_OR_TRUSTED_BOOT if EFI select HAVE_DYNAMIC_FTRACE_NO_PATCHABLE diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S index d33f060..190b803 100644 --- a/arch/x86/boot/compressed/head_64.S +++ b/arch/x86/boot/compressed/head_64.S @@ -38,6 +38,14 @@ #include "pgtable.h" /* + * Fix alignment at 16 bytes. Following CONFIG_FUNCTION_ALIGNMENT will result + * in assembly errors due to trying to move .org backward due to the excessive + * alignment. + */ +#undef __ALIGN +#define __ALIGN .balign 16, 0x90 + +/* * Locally defined symbols should be marked hidden: */ .hidden _bss diff --git a/arch/x86/include/asm/linkage.h b/arch/x86/include/asm/linkage.h index f484d65..9ee0e28 100644 --- a/arch/x86/include/asm/linkage.h +++ b/arch/x86/include/asm/linkage.h @@ -14,10 +14,8 @@ #ifdef __ASSEMBLY__ -#if defined(CONFIG_X86_64) || defined(CONFIG_X86_ALIGNMENT_16) -#define __ALIGN .p2align 4, 0x90 +#define __ALIGN .balign CONFIG_FUNCTION_ALIGNMENT, 0x90; #define __ALIGN_STR __stringify(__ALIGN) -#endif #if defined(CONFIG_RETHUNK) && !defined(__DISABLE_EXPORTS) && !defined(BUILD_VDSO) #define RET jmp __x86_return_thunk diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index c15de16..335b571 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -81,8 +81,8 @@ #define RO_EXCEPTION_TABLE #endif -/* Align . to a 8 byte boundary equals to maximum function alignment. */ -#define ALIGN_FUNCTION() . = ALIGN(8) +/* Align . function alignment. */ +#define ALIGN_FUNCTION() . = ALIGN(CONFIG_FUNCTION_ALIGNMENT) /* * LD_DEAD_CODE_DATA_ELIMINATION option enables -fdata-sections, which diff --git a/include/linux/linkage.h b/include/linux/linkage.h index 1feab61..5c8865b 100644 --- a/include/linux/linkage.h +++ b/include/linux/linkage.h @@ -69,8 +69,8 @@ #endif #ifndef __ALIGN -#define __ALIGN .align 4,0x90 -#define __ALIGN_STR ".align 4,0x90" +#define __ALIGN .balign CONFIG_FUNCTION_ALIGNMENT +#define __ALIGN_STR __stringify(__ALIGN) #endif #ifdef __ASSEMBLY__ diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 3fc7abf..e90dc67 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -467,6 +467,7 @@ config SECTION_MISMATCH_WARN_ONLY config DEBUG_FORCE_FUNCTION_ALIGN_64B bool "Force all function address 64B aligned" depends on EXPERT && (X86_64 || ARM64 || PPC32 || PPC64 || ARC) + select FUNCTION_ALIGNMENT_64B help There are cases that a commit from one domain changes the function address alignment of other domains, and cause magic performance