From mboxrd@z Thu Jan 1 00:00:00 1970 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.subspace.kernel.org (Postfix) with ESMTPS id DD67C372 for ; Tue, 2 Jul 2024 07:46:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.137.202.133 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719906421; cv=none; b=pJsG16HTbcdIz3yGfscfCLqk7h3UYy3IIhen6tq6fcHp7t9aHqqJ8Iwgx0U3IvxS66b1ktdT6KUmFaiVV9gnsHHSVq2I0o0LosmmyTOfoFksk0hAVpBnZz8lwbdVwURW6H4emnKyrHLmZtmZaT1pKiMJsO2F8xt35IzyHvrQeR8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719906421; c=relaxed/simple; bh=tiNLSFbwmrWL1v63VmX/iUohS0tBAcIcwEX2+ScDvDw=; h=Date:From:To:Cc:Subject:Message-ID:MIME-Version:Content-Type: Content-Disposition; b=sd8CAkUnw3x39XFDfxXrp/lBWnjouEU9mTi8a/j5wT4cZ2vV2OS4rDiYcKQydpj3cgj/HLKIW2lMjmN0l2GBAkua+idkamTEZR357qJ5YdwkUl5QxkZ47I5boMIhG7dkhFyr3rF3dUlRO+LN9LcG5mt5ZRdqLQxV8V18rZbnZn8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=bombadil.srs.infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=Z1fL29bJ; arc=none smtp.client-ip=198.137.202.133 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=bombadil.srs.infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="Z1fL29bJ" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=Content-Type:MIME-Version:Message-ID: Subject:Cc:To:From:Date:Sender:Reply-To:Content-Transfer-Encoding:Content-ID: Content-Description:In-Reply-To:References; bh=KwZmn1pJYr2O5Qca6G76MJZXUctSoTUPbm/W3gWQWEo=; b=Z1fL29bJVdaWjscaXZ5px1oezj 3STth2LdkVkXfHrX6QTIsNZsbWjGzaq3XfA3tdBOSdEuO/aqFgE7nBdCqoKcPRsB9OtH0Q9X1B9B3 tBfYDXJXJSPJiWc5R8aqWJgoY+NJVvK3ZNyzBJ/HIigfPlv1jJp4IZUQpIcaXd1W1ozSqygeK/z1J OrgYdwb7cWeE9JiwIhS8CT+YVGIcU6VuzmbJWH0bUW5WL4uJvCOPMQWHajTrbhRKmNS4pwY4HQef0 2P25gWMWJTuqG4APQ+brxfELuJeepP8C7kBckDeVLB51/BzN77ewGqC8vaetPHd1y0bHoktD70Rs7 ZX9PbkJQ==; Received: from hch by bombadil.infradead.org with local (Exim 4.97.1 #2 (Red Hat Linux)) id 1sOYE7-00000005u2D-27Y6; Tue, 02 Jul 2024 07:46:59 +0000 Date: Tue, 2 Jul 2024 00:46:59 -0700 From: Christoph Hellwig To: David Woodhouse , Lu Baolu Cc: iommu@lists.linux.dev Subject: lack of permission checking with intel-iommu? Message-ID: Precedence: bulk X-Mailing-List: iommu@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Hi all, we've recently had an interesting case where a device unexpectedly modified a dma buffer passed to it. On AMD systems this caused iommu faults because the buffer was mapped read only (DMA_FROM_DEVICE), but on an Intel system everything worked fine as the IOMMU did not trip up on the device writes to that buffer. Any idea why that could sneak through?