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 950E24A92F4; Wed, 2 Sep 2026 17:24:37 +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=1788369878; cv=none; b=XYuN5A83YvWtPSvgNCjHj01x780TuXgFM8dmmn5UEiMmn2Y8mCPZd4Vb0Moel6NUTqE3BxRiQGI0zfVzZ1hAuJUt7c54/rrXmzCBEYBYYNAo6F95bxXjNkV6Zt3+1uKBRx+crcil9llq9gFDy8kpYDQapxnUUzVUE4yBs0Z4o04= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788369878; c=relaxed/simple; bh=O2HTZ8oMi/55GiW97GxYG2jCA376NJNvFoe5bFDZISQ=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=BcuUqqKb4Mj7gna6S4oTud9OEU2tTol83Q0SjMT9D7/G2WDsGlt93K1KklkWvfcgKP/ktkQnrDWKnNDstGQLelXWEVNL2GciLq9UqthCLBDOaWorvPkg6K4Dit8LRa3eVMblbRmQo3wLFMnn6I6LMeY6HlcQTvRuh5f6Pho/4mM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=DXiOsd0I; 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="DXiOsd0I" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1164D1F000E9; Wed, 2 Sep 2026 17:24:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788369877; bh=l3/1naZ1RhLgUWY856SAbE6LeQ8PQwzS4dxBvl1l3nM=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=DXiOsd0IOwaWcqNMcESpWf4hFCXAp8Wnr0mmhtnowdnpJUppd8Az9ulZWwyJ2Uu4R wkSOKrsgXyrCbsZ4Ej8dCHAUO3I/4HPgFL476eGN0P/8NbBkNtGVWoaVvzxq629JSE MNyjdmuBfdWD9tp2ye9BdSsE7IZfLQ6ow1ntz6mprCCXuVX0AkCxGb50BYmQW7oBbd MPaDcJNFaSVqAkwRbQfma7hfoYES0jZcC+6XyiyrsPbnOzs3CpqliBh6dejcYwxVGB pQAl1sebDUlr62/dzSyXwzrWVKPVJmhKguUHvxr/r+W7Qs+BOd/D226mZ36jtpIbUb BuzrSWHmpSLjQ== Date: Wed, 2 Sep 2026 12:24:36 -0500 From: Rob Herring To: Vincent Donnefort Cc: catalin.marinas@arm.com, will@kernel.org, rppt@kernel.org, akpm@linux-foundation.org, sudeep.holla@kernel.org, jenswi@kernel.org, mark.rutland@arm.com, sumit.garg@kernel.org, ardb@kernel.org, thierry.reding@kernel.org, david@kernel.org, danielmentz@google.com, linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, op-tee@lists.trustedfirmware.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v9 02/10] of: reserved_mem: Introduce "ll-map" property Message-ID: <20260902172436.GB1440252-robh@kernel.org> References: <20260902104712.2399797-1-vdonnefort@google.com> <20260902104712.2399797-3-vdonnefort@google.com> Precedence: bulk X-Mailing-List: devicetree@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: <20260902104712.2399797-3-vdonnefort@google.com> On Wed, Sep 02, 2026 at 11:47:04AM +0100, Vincent Donnefort wrote: > Keeping last-level mappings is interesting on some architectures as it > allows mapping/unmapping pages from the kernel direct map without the > risk of splitting blocks which, under the break-before-make rule, may > trigger page-faults the kernel can't handle. > > Add an "ll-map" property for reserved-memory regions. When set, it > splits the underlying memblock and sets the MEMBLOCK_LLMAP flag. Where is this documented? Any DT property must have a schema. Though I'm not thrilled about more flag properties. Handling all the combinations of properties has proven to be painful. Can this be implied from the compatible string instead? Rob