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 52E0C3BED1E for ; Mon, 31 Aug 2026 08:39:52 +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=1788165593; cv=none; b=ILpPSyCEcMfy9ODoeo3nptzy+Cd9e3d13d5inuhhwd6odCc1wxLgbBDM/wfRjrrc4Te105OyzA7aeonRSK9z3FuvJ3iG4PG6pVhYyVJn0/QJnnLz8Hcbxn2jgcB7oSkrpNONtZb4dCM4TpeWDLvVlRVCY+L7Se+RCAheqI3h0MY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788165593; c=relaxed/simple; bh=utckoeSR1/t1en4mS6r3oK78zFlDfOozYh43GTzPoM0=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=fvGPTPDRqy6bG3qOA77rwdgLeTo4aWHszVRjmMyieUrnIFRTfS2FCBiHT8dCvM0NI3f1TKxBNMcFdZVdXgmSqRk21AFDzZEcVLA2I0gqZo4vvXLljtFCgWPp3G1qzw8m457f7LEr0BHJqAAv++q7ILeIcTean9brBkgCVBkzN0w= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ZlVQxh1p; 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="ZlVQxh1p" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5491D1F000E9; Mon, 31 Aug 2026 08:39:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788165591; bh=07DNzbG7Ea9A57I2ROWNCLeREPGQQY/UiEj2oMbahtM=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=ZlVQxh1pZrIF6IuHK9/Bj9Do89thFo+qT9twAC9fuI7+6I2wqDE704FVePsFSBjNY jUE7kviO2nwi2wjPX26x5gFT5kZi1W8J4DF7VSOpe2y058l0QxnqAGHId73E6G9RYT 3m76imtPCrTX5e42fIJwR7AEetVz5WUXkvl9NAQT+bY0iTpC3VMh8+Mi15tB8IPy2s mdkQYBwBPZi/91DaUq3zLSK1c7hgrGfkQblMr/xeN0cufEtvEwvUJaUCLNL4LpOIUu 5de49mrXyubaR14qUSd8vPitPPWs3+aqYzQ18SR7Wb9TopFDuQmf9md10Bfjb2NOxg 72bpVJcYXwWaA== Message-ID: <140594c6-0a39-4799-96f3-bbda79b6d832@kernel.org> Date: Mon, 31 Aug 2026 10:39:47 +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 v2] mm: adjust out-dated document of __GFP_NOFAIL Content-Language: en-US To: Wei Yang , akpm@linux-foundation.org, david@kernel.org, ljs@kernel.org, liam@infradead.org, rppt@kernel.org, surenb@google.com, mhocko@suse.com, brendan.jackman@linux.dev, hannes@cmpxchg.org, ziy@nvidia.com Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org References: <20260829025847.26779-1-richard.weiyang@gmail.com> From: "Vlastimil Babka (SUSE)" Autocrypt: addr=vbabka@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 8/29/26 04:58, Wei Yang wrote: > Commit ee040cbd6e48 ("mm/page_alloc: don't warn about large allocations > with __GFP_NOFAIL") remove a warning on allocating large folio with > __GFP_NOFAIL, which was placed there by commit 903edea6c53f ("mm: warn > about illegal __GFP_NOFAIL usage in a more appropriate location and > manner"). > > While in that commit, it also documented this behavior which is > out-dated now. > > Adjust the document to align to current code, and adjust the comment > while at it. > > Signed-off-by: Wei Yang Reviewed-by: Vlastimil Babka (SUSE) > > --- > v2: > * s/is adjusted/was placed there/ in change log > * instead of removing the document, say "is discouraged" > > v1: https://lore.kernel.org/all/20260827030548.16631-1-richard.weiyang@gmail.com/T/#u > --- > include/linux/gfp_types.h | 2 +- > mm/page_alloc.c | 2 +- > 2 files changed, 2 insertions(+), 2 deletions(-) > > diff --git a/include/linux/gfp_types.h b/include/linux/gfp_types.h > index 190191411009..bfd4c43ed777 100644 > --- a/include/linux/gfp_types.h > +++ b/include/linux/gfp_types.h > @@ -244,7 +244,7 @@ enum { > * definitely preferable to use the flag rather than opencode endless > * loop around allocator. > * Allocating pages from the buddy with __GFP_NOFAIL and order > 1 is > - * not supported. Please consider using kvmalloc() instead. > + * discouraged. Please consider using kvmalloc() instead if possible. > */ > #define __GFP_IO ((__force gfp_t)___GFP_IO) > #define __GFP_FS ((__force gfp_t)___GFP_FS) > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > index ab385bc252cc..146f7e0a9462 100644 > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -4804,7 +4804,7 @@ __alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order, > > if (unlikely(nofail)) { > /* > - * Also we don't support __GFP_NOFAIL without __GFP_DIRECT_RECLAIM, > + * We don't support __GFP_NOFAIL without __GFP_DIRECT_RECLAIM, > * otherwise, we may result in lockup. > */ > WARN_ON_ONCE(!can_direct_reclaim);