From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 6E0D8270545; Fri, 24 Apr 2026 13:02:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777035762; cv=none; b=QsWjdX3rSfNvt3s1JQvYhRO+wnf08nLWXpLw/IcwG8tyxxM1bv4KsDtoA+YbUgUW63cfv7K1+cE286en+/sN8gdL9qWfa04OjP8LeH5PzLGFgc/w0HvvkwwisId51QQPRg72rYp5AP8RKUAJdP+dcLUNzkUMxmhHUEJ14O2Vdl4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777035762; c=relaxed/simple; bh=uOi1Rk96oeur1i6i7Mh3ItL6sBlXiIQnfqF3cWvMO04=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=WewWa5A3GMsRvEOcZm1iM0uadWEBhtTdfhzWxE8KiSK2ikfvqC1a6DvWlePKmFE5zWKgmApmemIvKDB+2J16xaBSyOsK0/yoW0NHo1/Q6hhttOUP6FFY4GMOPCnkbmMw1zgM5+gk0acRC5vYE1kj7tMFa5DptCFEhlEe+Ljj1U4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b=mqr3co6o; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b="mqr3co6o" 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 54E8F1BB0; Fri, 24 Apr 2026 06:02:34 -0700 (PDT) Received: from a080796.blr.arm.com (a080796.arm.com [10.164.21.51]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id CAE253F641; Fri, 24 Apr 2026 06:02:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1777035759; bh=uOi1Rk96oeur1i6i7Mh3ItL6sBlXiIQnfqF3cWvMO04=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=mqr3co6oZde7WmeQ7llcR+8DKaBN6lEdV2rzuhYWXuiAOG/rOW4u/uqnqvMcnrVT9 WNtGghnwtzskbxD0OblP/47MNHQJQeWXs7DPMybVKZtIhHS+GFf2mzbMd1Ey9XuzMi vJHvOkfbleWtTQT86FCRDg5sXi0b91IgL4QhTL20= From: Dev Jain To: arnd@arndb.de, kees@kernel.org, mingo@redhat.com, peterz@infradead.org, juri.lelli@redhat.com, vincent.guittot@linaro.org, akpm@linux-foundation.org, david@kernel.org, urezki@gmail.com Cc: dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de, vschneid@redhat.com, ljs@kernel.org, Liam.Howlett@oracle.com, vbabka@kernel.org, rppt@kernel.org, surenb@google.com, mhocko@suse.com, tglx@kernel.org, usama.anjum@arm.com, mathieu.desnoyers@efficios.com, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Ryan Roberts , Catalin Marinas Subject: [PATCH v3 3/3] mm: skip KASAN tagging for page-allocated page tables Date: Fri, 24 Apr 2026 18:31:57 +0530 Message-Id: <20260424130157.3163009-4-dev.jain@arm.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20260424130157.3163009-1-dev.jain@arm.com> References: <20260424130157.3163009-1-dev.jain@arm.com> Precedence: bulk X-Mailing-List: linux-arch@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Muhammad Usama Anjum Page tables are always accessed via the linear mapping with a match-all tag, so HW-tag KASAN never checks them. For page-allocated tables (PTEs and PGDs etc), avoid the tag setup and poisoning overhead by using __GFP_SKIP_KASAN. SLUB-backed page tables are unchanged for now. (They aren't widely used and require more SLUB related skip logic. Leave it later.) Reviewed-by: Ryan Roberts Signed-off-by: Muhammad Usama Anjum Acked-by: David Hildenbrand (Arm) Reviewed-by: Catalin Marinas --- include/asm-generic/pgalloc.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/include/asm-generic/pgalloc.h b/include/asm-generic/pgalloc.h index 57137d3ac1592..051aa1331051c 100644 --- a/include/asm-generic/pgalloc.h +++ b/include/asm-generic/pgalloc.h @@ -4,7 +4,7 @@ #ifdef CONFIG_MMU -#define GFP_PGTABLE_KERNEL (GFP_KERNEL | __GFP_ZERO) +#define GFP_PGTABLE_KERNEL (GFP_KERNEL | __GFP_ZERO | __GFP_SKIP_KASAN) #define GFP_PGTABLE_USER (GFP_PGTABLE_KERNEL | __GFP_ACCOUNT) /** -- 2.34.1