From patchwork Thu Sep 26 13:38:03 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vincenzo Frascino X-Patchwork-Id: 11162777 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 7ADBF924 for ; Thu, 26 Sep 2019 13:39:45 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 54208222C0 for ; Thu, 26 Sep 2019 13:39:45 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="FTk3mGP2" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 54208222C0 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=qwYUUiWgNQ+ucr6sj5Qi7ITNFfqdmjFU5ItBj/AGuUs=; b=FTk3mGP2RZudGn ETuc/0iTaCpDbMoHa4SzjmSmkdjhTeisx/iRJ+Mtz8Tbn9KrfgMpPG20r1cP3MVKGUg2cUjLMMJy+ MLmchro/OaFymibm1LWDoczjYZ+Pjw93zBcb8Q4R75E+Tukxi3UeU8TEgkXikrm3sIUCcvBl8i3ZJ CkRe5LCOJ2C4q21VdYh4CyUUX3MT1BOazVDSV8MvPThERh7AEGwZamkXJ9nQnH+dh5PBlKdA+VImB JZKmZ+DjlFFbkQRaHpCnZZcU/b+sOX43wQSwoQ5cp6bhpUhJf/G5gghgdBJJmzQXY2RbmBAASoVlH UDDbP7UPxKPh6vRzliAQ==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.2 #3 (Red Hat Linux)) id 1iDTzk-0007U3-Ri; Thu, 26 Sep 2019 13:39:44 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.92.2 #3 (Red Hat Linux)) id 1iDTyp-00070N-QK for linux-arm-kernel@lists.infradead.org; Thu, 26 Sep 2019 13:38:49 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 7393E1596; Thu, 26 Sep 2019 06:38:47 -0700 (PDT) Received: from e119884-lin.cambridge.arm.com (e119884-lin.cambridge.arm.com [10.1.196.72]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 519CF3F534; Thu, 26 Sep 2019 06:38:46 -0700 (PDT) From: Vincenzo Frascino To: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 2/4] arm64: vdso32: Detect binutils support for dmb ishld Date: Thu, 26 Sep 2019 14:38:03 +0100 Message-Id: <20190926133805.52348-3-vincenzo.frascino@arm.com> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20190926133805.52348-1-vincenzo.frascino@arm.com> References: <20190920142738.qlsjwguc6bpnez63@willie-the-truck> <20190926133805.52348-1-vincenzo.frascino@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190926_063847_983004_A8156CC3 X-CRM114-Status: GOOD ( 11.99 ) X-Spam-Score: 0.0 (/) X-Spam-Report: SpamAssassin version 3.4.2 on bombadil.infradead.org summary: Content analysis details: (0.0 points) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 SPF_PASS SPF: sender matches SPF record 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: ard.biesheuvel@linaro.org, catalin.marinas@arm.com, ndesaulniers@google.com, tglx@linutronix.de, vincenzo.frascino@arm.com, will@kernel.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org As reported by Will Deacon, older versions of binutils that do not support certain types of memory barriers can cause build failure of the vdso32 library. Add a compilation time mechanism that detects if binutils supports those instructions and configure the kernel accordingly. Cc: Will Deacon Cc: Catalin Marinas Signed-off-by: Vincenzo Frascino --- arch/arm64/Kbuild | 6 ++++++ arch/arm64/include/asm/vdso/compat_barrier.h | 2 +- arch/arm64/kernel/vdso32/Makefile | 9 +++++++++ 3 files changed, 16 insertions(+), 1 deletion(-) diff --git a/arch/arm64/Kbuild b/arch/arm64/Kbuild index d6465823b281..75cf8c796d0e 100644 --- a/arch/arm64/Kbuild +++ b/arch/arm64/Kbuild @@ -4,3 +4,9 @@ obj-$(CONFIG_NET) += net/ obj-$(CONFIG_KVM) += kvm/ obj-$(CONFIG_XEN) += xen/ obj-$(CONFIG_CRYPTO) += crypto/ + +# as-instr-compat +# Usage: cflags-y += $(call as-instr-compat,instr,option1,option2) + +as-instr-compat = $(call try-run,\ + printf "%b\n" "$(1)" | $(COMPATCC) $(KBUILD_AFLAGS) -c -x assembler -o "$$TMP" -,$(2),$(3)) diff --git a/arch/arm64/include/asm/vdso/compat_barrier.h b/arch/arm64/include/asm/vdso/compat_barrier.h index fb60a88b5ed4..3fd8fd6d8fc2 100644 --- a/arch/arm64/include/asm/vdso/compat_barrier.h +++ b/arch/arm64/include/asm/vdso/compat_barrier.h @@ -20,7 +20,7 @@ #define dmb(option) __asm__ __volatile__ ("dmb " #option : : : "memory") -#if __LINUX_ARM_ARCH__ >= 8 +#if __LINUX_ARM_ARCH__ >= 8 && defined(CONFIG_AS_DMB_ISHLD) #define aarch32_smp_mb() dmb(ish) #define aarch32_smp_rmb() dmb(ishld) #define aarch32_smp_wmb() dmb(ishst) diff --git a/arch/arm64/kernel/vdso32/Makefile b/arch/arm64/kernel/vdso32/Makefile index 1fba0776ed40..22f0d31ea528 100644 --- a/arch/arm64/kernel/vdso32/Makefile +++ b/arch/arm64/kernel/vdso32/Makefile @@ -17,6 +17,8 @@ cc32-disable-warning = $(call try-run,\ $(COMPATCC) -W$(strip $(1)) -c -x c /dev/null -o "$$TMP",-Wno-$(strip $(1))) cc32-ldoption = $(call try-run,\ $(COMPATCC) $(1) -nostdlib -x c /dev/null -o "$$TMP",$(1),$(2)) +cc32-as-instr = $(call try-run,\ + printf "%b\n" "$(1)" | $(COMPATCC) $(VDSO_AFLAGS) -c -x assembler -o "$$TMP" -,$(2),$(3)) # We cannot use the global flags to compile the vDSO files, the main reason # being that the 32-bit compiler may be older than the main (64-bit) compiler @@ -55,6 +57,7 @@ endif VDSO_CAFLAGS += -fPIC -fno-builtin -fno-stack-protector VDSO_CAFLAGS += -DDISABLE_BRANCH_PROFILING + # Try to compile for ARMv8. If the compiler is too old and doesn't support it, # fall back to v7. There is no easy way to check for what architecture the code # is being compiled, so define a macro specifying that (see arch/arm/Makefile). @@ -91,6 +94,12 @@ VDSO_CFLAGS += -Wno-int-to-pointer-cast VDSO_AFLAGS := $(VDSO_CAFLAGS) VDSO_AFLAGS += -D__ASSEMBLY__ +# Check for binutils support for dmb ishld +dmbinstr := $(call cc32-as-instr,dmb ishld,-DCONFIG_AS_DMB_ISHLD=1) + +VDSO_CFLAGS += $(dmbinstr) +VDSO_AFLAGS += $(dmbinstr) + VDSO_LDFLAGS := $(VDSO_CPPFLAGS) # From arm vDSO Makefile VDSO_LDFLAGS += -Wl,-Bsymbolic -Wl,--no-undefined -Wl,-soname=linux-vdso.so.1