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 5D9063B05AC for ; Wed, 23 Sep 2026 17:20:05 +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=1790184006; cv=none; b=X5JzFWd9/B9ofof1cZcTxFZ+tFGkKc4lyBMBKwotE+Kgmc8JGc90dpUugjsfNKHjDaRspASEj/xeB5+Sy2GH+Q9wXgoEsdgXH8CcsOekoN4MGUSinBt87xQitnwa2OTp7Ac4qznT0LUN0RfX181/0KQSsnUFaxdVihYQmUzFqQM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790184006; c=relaxed/simple; bh=MxtHe5AamXMxVbm2/Ky2ftro9DnKxsKwPN1FA0EfMCE=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=gkqNUxJajvBlfyO4isnd1Le7MZS2Inj6RnJybTwSJMgfm+I7S0IRgdx3celUFOgD46Kmd6idef1lAyL9LsuKIdtPSwV+R36bI9ksmN95SLMNjP8y7bKZrIsP8ISvIW5nwviXr7WMc1l0oESUKAky2x6U7O5rSaUzWpR75f+Dp4Y= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=P9ikKe5M; 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="P9ikKe5M" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B68F01F00893; Wed, 23 Sep 2026 17:19:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1790184005; bh=7IKIebDSAi0EpVNQOnavA/xUruPOvaI5w9nTcWcEOKI=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=P9ikKe5M0p256JAWOmy5NpxEFMkd1pZJL5H1ErHaarxIVJt89Rx0Z7mrmEOcaP9bj OP0r9+Bq0mAi5xwOgvsk5wy05AHM0WC1nypEPbID7g0sA05crXE/HQ9vlK7XDdQMEZ nd0FhGT+RyLVFSLWdgoyRDFAYUgvnAo8n/uKLaQeY/xJYsV65hPL4y/AdCrV3Um6jF Q2gZznSezWmB6iQv9Ig1af65X6giq/al/H788jIiLeAsh2jvtTLt8D9738g9Ci75xQ n16q4pY8ss8GHXoozBP3AzV7JAlNULy4Emt0rLmlrUxBGssS8TTyDEptRGMYTr9v1b mrDIOXVgEjj4Q== Message-ID: <141d58e1-5663-482b-ab61-956f3b08081b@kernel.org> Date: Wed, 23 Sep 2026 19:19:57 +0200 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] mm/page_alloc: let the bulk and folio allocators carry alloc_flags Content-Language: en-US To: Gregory Price Cc: Lance Yang , linux-mm@kvack.org, linux-kernel@vger.kernel.org, kernel-team@meta.com, akpm@linux-foundation.org, surenb@google.com, mhocko@suse.com, brendan.jackman@linux.dev, hannes@cmpxchg.org, ziy@nvidia.com, david@kernel.org, ljs@kernel.org, liam@infradead.org, rppt@kernel.org, baolin.wang@linux.alibaba.com, nico.pache@linux.dev, ryan.roberts@arm.com, dev.jain@arm.com, baohua@kernel.org, usama.arif@linux.dev, kas@kernel.org, matthew.brost@intel.com, joshua.hahnjy@gmail.com, rakie.kim@sk.com, byungchul@sk.com, ying.huang@linux.alibaba.com, apopple@nvidia.com References: <20260914155115.439742-1-gourry@gourry.net> <20260922130558.48402-1-lance.yang@linux.dev> <80206444-d0c3-4dab-a5e3-a2909e58ea33@kernel.org> From: "Vlastimil Babka (SUSE)" Autocrypt: addr=vbabka@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 9/23/26 17:24, Gregory Price wrote: > On Wed, Sep 23, 2026 at 08:32:29AM +0200, Vlastimil Babka (SUSE) wrote: >> On 9/23/26 03:59, Gregory Price wrote: >> > On Tue, Sep 22, 2026 at 09:05:58PM +0800, Lance Yang wrote: >> > >> > There is some concern around NOLOCK here yes, in fact sashiko picked >> > this issue up and I've been poking at it. >> >> It's possible to document it as unsupported, add a VM_WARN_ON_ONCE etc. >> It's not necessary for bulk alloc to support ALLOC_NOLOCK just because it >> takes flags. e.g. kmalloc_nolock() supports a subset of gfp flags as well. >> > > It seemed simpler to just support it than to create more future > footguns. I can RFC my current rework if you like, i attempted > to deduplicate the logic via a prepare_alloc_flags() called from > both the bulk and non-bulk contexts. Ok if it's simple enough, lets see :) Thanks > But if we prefer the WARNs over adding the new semantics to the bulk > allocator, that also doesn't seem unreasonable. > > ~Gregory