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 58EA247F2CE for ; Thu, 20 Aug 2026 17:33:08 +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=1787247189; cv=none; b=gkQ8J9oW0FfXhy7vRRyvtn2p+Z3TY/avFmdmGYt8rhV2J8SIZV8AjyLdS+8Ihto/L9qpjWfswL2PiZtivbiD4WhwVX/GEpkHXt7+iMuwdbclcljjeXexwCjPB9BrJXZDAAXZ1Fx5RgUdlpsM/w2DnlBdnQcP5af9DFZURUtOA+w= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787247189; c=relaxed/simple; bh=pZYvLpHtgZAAykiZjyBoQSCVyhRZWEHdSKQRXccEWWo=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=C/71DzOwzZVWGSkNvXuYBiL/TdIjdGnpS0gH1vwrgTzNycNOkfnu34wyykSz1aYuKZzwWurgXNNmuxwpabxibPt5k4YrTIm6vdzZj9Di8DAW6Ir+jDHkaaKluMNnaQo+Nqvr9rV/j2N+zvzroTGL6aJ3o6dlYZHzYZcxbsBX3Z4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=AxQmEyM3; 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="AxQmEyM3" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 838781F000E9; Thu, 20 Aug 2026 17:33:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1787247188; bh=xKZbzHEs7LovNAK73CuUY9PodbupBOZ3Tf7iuO/vCJM=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=AxQmEyM337L8/XC13vNqg2pJ/asCDJblMcM09Fj0giGxOGzcQJrT72m510uGyz+Si R7BAYktFs8f84fHzhqraAynMY+KEvnG3Hb9NGFIGlSucH8betFIvM4Q8yxKS5t2IKt qkflSYIN0MpkMRupcyw8y8xG2RcQyg/1VV2Xx6nL/tLpgpWPRNj4yYuYP2S8juGNPJ YNIWVdr71kwTXMYgCcfWBnKxzLTn5p7ttDkzXKMn4Z43z7nSIg3OzZzcdlaO8yZE1b RToj3UnvuNBfO0C1rTJUA3p710gDr3q1xukkTFGFtqdL/cNOLsogfLkJpSJv9ZXbuP ABak8h1qTcfPQ== Message-ID: Date: Thu, 20 Aug 2026 19:33:03 +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 1/1] mm/hugetlb: do not dissolve gigantic pages without runtime support To: Muchun Song Cc: Longlong Xia , osalvador@suse.de, akpm@linux-foundation.org, mike.kravetz@oracle.com, mhocko@suse.com, linmiaohe@huawei.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Longlong Xia References: <20260817162039.1511838-1-xialonglong2025@163.com> <206cb1f2-b66c-4b7b-b0ad-14cca9d8e0bd@kernel.org> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 8/20/26 11:38, Muchun Song wrote: > > >> On Aug 19, 2026, at 16:52, David Hildenbrand (Arm) wrote: >> >> On 8/17/26 18:20, Longlong Xia wrote: >>> From: Longlong Xia >>> >>> dissolve_free_hugetlb_folio() doesn't check hstate_is_gigantic_no_runtime(h) >>> though remove_hugetlb_folio()/update_and_free_hugetlb_folio() silently >>> bail for such folios >> >> That's odd. Why do they silently skip such folios instead of warning that >> something unexpected is happening? >> >> This screams for a cleanup unless I am missing something :) > > Hi David, > > Sashiko actually has a pretty detailed description [1]. So I think it deserves a fix. That's not what I meant. I agree that its a valid fix, but I think the code should possibly be reworked to not get silent rejection from these functions--IOW, likely the callers should make sure to never call them in this scenario, and then VM_WARN_ON() instead of handling it silently. -- Cheers, David