From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 12D09348C77; Sat, 15 Aug 2026 04:45:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786769152; cv=none; b=RpOkvGhUBJyY8eXRW/GSYvt6t3jfhtbqyo3rd2+OEm2VTnhUL7huYXAzDmWN53cZAvea0ijkHwqlmHTh26Xo1iJQbG+hMqw96cUjt9BmRvuHqbpf+sY+xMjQk1NBgOrq+0X1iEk/qjI+yDk9rXAsPcSwYeTmnAnT3ngtGJYN4lM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786769152; c=relaxed/simple; bh=Qc8dmVi3VPYi3jyIDF7WQ4WF7JOsXyd2qQaCAyX6ZcE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=aZk3efCkjOrnGbo4Db0P7oJZk514/wBqt+SbqyhAX1cr36038ZOIMxKN1UpdeZagXHmJhjnGomBZ2ChXksmr4dWmv4UG9qVyRqXUCcGQkvsN2v+WD4cJcJWN/B6MQf7AwVDg1dsaCN8XSM9IsNGU331y2uyEQHdwVnPl4XyKYKc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Yh2lWpvn; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Yh2lWpvn" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 68A381F00A3A; Sat, 15 Aug 2026 04:45:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1786769151; bh=y3RAP4/V/S2Ka1HZIeZ+MI/MmRFw0KCRbzs9mdx3m/8=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=Yh2lWpvnhz/fqU5jrXmd7zdXBwN04vdE8Z/rdgzWLKG0vWbPRSF34Y4UJkIZSwTOs S4CkWWnCpBwkjvzo5FcwdusCciF7mOItmOGAPwvIuWuELsPaQOJ8gcLAnu460XMtlo QO2PATvBByJLhdu2UjJ1jhXdjUsQi9BzR61XVcp/Y0VZgDpOkm80/sHY4DCroSkdzW MtvS3EAex7G0Oqsiug7sSJekBehikkGIdr0L2ZpJe0ss1IlPNA70ziImVNr3QlEnYx P7rBvcsr3r2B2TWM/tPLvFq1yVFWnUyh8HFFnVf4g/SCwrGzMEZIX+SXJpQm0bFbY6 QmA21yYigQvIQ== From: Josh Poimboeuf To: Catalin Marinas , Will Deacon Cc: linux-kernel@vger.kernel.org, Ard Biesheuvel , linux-arm-kernel@lists.infradead.org, live-patching@vger.kernel.org, Song Liu , Miroslav Benes , Petr Mladek , Joe Lawrence , Mark Rutland , Mark Brown , Nick Desaulniers , Kees Cook , Nathan Chancellor , linux-toolchains@vger.kernel.org Subject: [PATCH 11/12] arm64/bti: Force-enable BTI linker veneers Date: Fri, 14 Aug 2026 21:45:28 -0700 Message-ID: X-Mailer: git-send-email 2.55.0 In-Reply-To: References: Precedence: bulk X-Mailing-List: linux-toolchains@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit The linker only emits the BTI veneers if *all* input objects have GNU_PROPERTY_AARCH64_FEATURE_1_BTI. All the kernel's objects now advertise it, but if some object stops doing so, BTI veneers silently stop getting created on >128MB kernels, resulting in BTI exceptions at runtime. Force BTI veneers enabled with "-z force-bti" to prevent a single bad object from ruining things. This also emits a warning (or error with CONFIG_WERROR) if any objects are missing the bit. Signed-off-by: Josh Poimboeuf --- arch/arm64/Makefile | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/arm64/Makefile b/arch/arm64/Makefile index 4eee721c0b278..d0db9a6766a2f 100644 --- a/arch/arm64/Makefile +++ b/arch/arm64/Makefile @@ -25,6 +25,7 @@ endif ifeq ($(CONFIG_ARM64_BTI_KERNEL),y) KBUILD_AFLAGS += -include $(srctree)/arch/arm64/include/asm/bti-note.h +LDFLAGS_vmlinux += $(call ld-option,-z force-bti) endif cc_has_k_constraint := $(call try-run,echo \ -- 2.55.0