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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id CF269EC1127 for ; Mon, 23 Feb 2026 19:20:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=DiYyWpmhcZm4OWbfJXG7CY2HOC5E9m6BFTB1qFD7pd4=; b=JNuoMUs+IpMKuTQ4tZ41WRpBVK D/6tO4F9aCK3wbXHH+k8pq4BVE940ZT4zMrZ+jc6AX5KY6ycPHeDD5AAN3gF55QC9U0phmYVpb8vk fWaf4VNLUORXMTPrq3wjL00v6l2mfXn7SPmRu6YwFmcsVUDjmI1ubv0Y7vtnDAeVbdU2jIR/vOL+2 WTPV46VQntfu/mUwaPOX3XqpYnGcxpaynIpaCDj/GmRVF9/WunS56BHDjxDs2BqitiMrQl6ruUrgC qVisLbA+jCU69jvPRCUaCX4ot1UKRZoiqTG0NjZWUsDh71m9EkLmmsOcoa15xKm/qolgNGFifW4jz sasTkZRQ==; 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charset=UTF-8 Content-Transfer-Encoding: 7bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260223_112040_796456_31084E5F X-CRM114-Status: UNSURE ( 9.75 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 2/23/26 18:45, Catalin Marinas wrote: > vm_get_page_prot() short-circuits the protection_map[] lookup for a > VM_SHADOW_STACK mapping since it uses a different PIE index from the > typical read/write/exec permissions. However, the side effect is that it > also ignores mprotect(PROT_NONE) by creating an accessible PTE. > > Special-case the !(vm_flags & VM_ACCESS_FLAGS) flags to use the > protection_map[VM_NONE] permissions instead. No GCS attributes are > required for an inaccessible PTE. > > Signed-off-by: Catalin Marinas > Fixes: 6497b66ba694 ("arm64/mm: Map pages for guarded control stack") > Cc: > Cc: Mark Brown > Cc: Will Deacon > Cc: David Hildenbrand > --- Reviewed-by: David Hildenbrand (Arm) -- Cheers, David