From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (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 6C74C288D0 for ; Wed, 14 Jan 2026 02:06:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768356390; cv=none; b=L79qg3hnhAbs1lueOzSn3h+7s/yPcyRy37+xdlmk6NNh0TqpmJII4xOMM/Z9ewVKJ+gXA1lo/w23WJv6Mczlhz1wXeYwYi71OAx7jr9JbOGurI3d37xSURBY/n/jDlpD419/7gIP9AhD+Ow3v37qJWSFXezwOrVkzx48cSlymww= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768356390; c=relaxed/simple; bh=mxxPq5w/E7Gd3e0e7u8YHYAwZdMSNYHiy/Ttuj4ER8U=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=l96T4+7bOcF0/aqhdnWlDsagpouC5ENYcRcEw0pYv32JlN/HzpzIQnHb3oBWV2LtxwnKR2BjSd+YK9OZKFRqUxMX9vUdwjoAyxmIKzgQQwq3MzVlFJH3mOoD8oqMXgMWMqlF4yFlndg2NVF7qVjbQo29HA5SmEWYmZLYFaVD+PU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=O0XnlOQk; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="O0XnlOQk" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1768356388; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=vt6KalF0r8vwIUDZBExCxJCgnOwTB1qh1qLPxOxvRhw=; b=O0XnlOQks2dvrIEA56/oUaD2mGRFJSnS7KfWg6oggQziBnjRx0KA2g9iioDPuTLTf9maJ5 AdbkyuGuUoqz0NWrLhiXG99E8LTrspqrQToc6tPnb2pUJPP10upvGT081/pwLETmioB6HH BEV9uugH3hCeo7VUa4yEYNcquh0mGo4= Received: from mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-602-fEQgJ9YAOiqbzV-F7C3eGw-1; Tue, 13 Jan 2026 21:06:22 -0500 X-MC-Unique: fEQgJ9YAOiqbzV-F7C3eGw-1 X-Mimecast-MFC-AGG-ID: fEQgJ9YAOiqbzV-F7C3eGw_1768356380 Received: from mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.12]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 1A5411954204; Wed, 14 Jan 2026 02:06:20 +0000 (UTC) Received: from localhost (unknown [10.72.112.63]) by mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 3A3941955F24; Wed, 14 Jan 2026 02:06:17 +0000 (UTC) Date: Wed, 14 Jan 2026 10:06:13 +0800 From: Baoquan He To: Robin Murphy Cc: m.szyprowski@samsung.com, akpm@linux-foundation.org, vbabka@suse.cz, david@kernel.org, iommu@lists.linux-foundation.org, linux-mm@kvack.org, vladimir.kondratiev@mobileye.com, s-adivi@ti.com, linux-kernel@vger.kernel.org, lorenzo.stoakes@oracle.com, Liam.Howlett@oracle.com, rppt@kernel.org, surenb@google.com, mhocko@suse.com, jackmanb@google.com, hannes@cmpxchg.org, ziy@nvidia.com Subject: Re: [PATCH 0/3] dma-mapping: Improve atomic pool behaviour Message-ID: References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Scanned-By: MIMEDefang 3.0 on 10.30.177.12 On 01/12/26 at 03:46pm, Robin Murphy wrote: > Hi all, > > These days we have somewhat of a matrix of mm zones that may or may not > exist and may or may not be empty, which the per-zone atomic pool logic > doesn't actually handle all that well. It's not all that difficult to > improve robustness and reduce redundancy, so that's what this series > aims for. > > I initially wrote this just because I happened to be looking through the > boot log of one of my boards and had one of those out-of-the-blue > realisations of "hang on, why *is* it allocating pools for zones it > doesn't even have memory in?", but coincidentally, it seems that others > happened to notice related aspects around the same time[1][2]. This is > my attempt to sort it all out properly. Reviewed-by: Baoquan He