From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 9274113D240 for ; Tue, 26 Mar 2024 20:27:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711484847; cv=none; b=ZEXX9hYmV1g+ZUjLTxnT7iOG/U0OVJhJyy6fSB6KpePi25qJKeHGazAqR4lPRIz1rhQQaoateFbfhj8vdsuCKddm9CoUePtuDByUTk3hfCmSaxhwfln+8BCoSUc9RvRzULmAWN8iaxVdHAGYihkd5KIB/Hf1igH4E2Y+PMnCbb8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711484847; c=relaxed/simple; bh=RMc55HDt1Iu9wEhlfvQPgk2yHzSGgjRT7fuSwVCTZQ0=; h=Date:From:To:Cc:Subject:Message-Id:In-Reply-To:References: Mime-Version:Content-Type; b=eUYml4XdazKjju/Pab9YLSJGYvujW0gJVTnYBO65ZnR29PVJsn15dO8f560/m512d/LMGWnA9Qmoef8MRB16+Xk3ammTjAxCpdTwniZQFLwE6kJ70R+iFOsUK3lKA6goXyOhIKDM8ru6uk9c5pfA9dDxPNUtCh4ihq0MdAIi8WQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=NpetpB26; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="NpetpB26" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E0F54C433C7; Tue, 26 Mar 2024 20:27:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1711484847; bh=RMc55HDt1Iu9wEhlfvQPgk2yHzSGgjRT7fuSwVCTZQ0=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=NpetpB26CHhvYKzvBW/oKi5wtOnub6rL5aP+YF9Y6dCvsmN12zKb5dHIZ5CfCYKcn mhpXZyqvSxsBryWoD/L3dVJ01wZpPDe2ffb+0OvtOWbu8EvYvgn6fD5h7/2417uMPL RI0ydEygACM/q2kOjDEnIbOri4aJ/Y/b5mxPbfOs= Date: Tue, 26 Mar 2024 13:27:26 -0700 From: Andrew Morton To: peterx@redhat.com Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, SeongJae Park , Jason Gunthorpe , Mike Rapoport , Matthew Wilcox , kernel test robot Subject: Re: [PATCH] mm/arch: Provide pud_pfn() fallback Message-Id: <20240326132726.67e82559a928ac1636c8050c@linux-foundation.org> In-Reply-To: <20240323151643.1047281-1-peterx@redhat.com> References: <20240323151643.1047281-1-peterx@redhat.com> X-Mailer: Sylpheed 3.8.0beta1 (GTK+ 2.24.33; x86_64-pc-linux-gnu) 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-Transfer-Encoding: 7bit On Sat, 23 Mar 2024 11:16:43 -0400 peterx@redhat.com wrote: > From: Peter Xu > > The comment in the code explains the reasons. We took a different approach > comparing to pmd_pfn() by providing a fallback function. > > Another option is to provide some lower level config options (compare to > HUGETLB_PAGE or THP) to identify which layer an arch can support for such > huge mappings. However that can be an overkill. > > ... > > If we care about per-commit build errors (and if it is ever feasible to > reorder), we can move this patch to be before the patch "mm/gup: handle > huge pud for follow_pud_mask()" in mm-unstable to unbreak build on that > commit. I temporarily disabled that whole series a few days ago. Because of multiple build issues, iirc. Let's make that permanent. Please redo the whole series against mm-unstable and resend?