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 8709C3446D2; Mon, 22 Dec 2025 10:28:51 +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=1766399331; cv=none; b=dPd6pfrKHJ+q8xQlnLmFeKFzWxhMRlr3lQiMYfF3qy76r7XnFEf0m4m9ZOD0j8XMYxL4S+ialhTiiSCnLjG+/VocdHXUW65LcdiG3MjQlXOMdQLaucRUY0eW0omgeragghvK7RccU1fNlzK7RKp3PqlIxFN6voCOPbQsGStsXVY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1766399331; c=relaxed/simple; bh=gpI81CYAZDI5HhhxXAwfSCUYaYR7sSbyLFN423qq0Z8=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=XEqYaELX+aCT1wmKGKTwr00hPp0lHqfMS+/E5qyoGPtVBlpBeCs5jNa+f4r6RpfPUYoHiB7u0dQFIHicUKo7ezS48jT4wtjA16CehucifSDubvVAIAnQ4srODIkqEPjhLiLTAU7HDwvHryJfmpvDf1ZM7MbnKGwJsc6EmzcqBHc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=mzi5UKY+; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="mzi5UKY+" Received: by smtp.kernel.org (Postfix) with ESMTPSA id AAFE9C4CEF1; Mon, 22 Dec 2025 10:28:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1766399331; bh=gpI81CYAZDI5HhhxXAwfSCUYaYR7sSbyLFN423qq0Z8=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=mzi5UKY+SCvVFYHfm5csTU5OI5er+dNklX9M5m/zec7X5fgX33WqOMbRBtk83enAa OvCxPPfAahY/yFpkkTd4hZ530UhdVQLFACAX1EHZBBAxzMcBLg3RdOTdKs8s0OGnoa laMPM1Rh+W/W8wsGe4ej6Ds3yrnXVkVDiZTlkHGUJvPTdBlxF2qE0V2hDFEEeXLyWZ hBDQGVdCa4J8o3OUq9ldWfnMXOi3+kNjaTgBbDq3Q0mjCHIm6QPqAlD2604+OaiqMJ 2AZ4wdtOrh99mmswzzFltUtta6Xn7nX84Aodf9HucX2Yc7T6xHrHjnlug9uPBbpQTE 0HhhJWryqziRg== Message-ID: <051628be-ed70-4a56-8704-f2b8cdea1984@kernel.org> Date: Mon, 22 Dec 2025 11:28:43 +0100 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 v6] mm/hugetlb: ignore hugepage kernel args if hugepages are unsupported To: Sourabh Jain , "Ritesh Harjani (IBM)" , Andrew Morton Cc: Borislav Petkov , Christophe Leroy , Heiko Carstens , Ingo Molnar , Madhavan Srinivasan , Michael Ellerman , Muchun Song , Oscar Salvador , Thomas Gleixner , Vasily Gorbik , linux-mm@kvack.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, x86@kernel.org, linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org References: <20251221053611.441251-1-sourabhjain@linux.ibm.com> <87a4zcml36.ritesh.list@gmail.com> <655cc605-2ce1-4ccb-8cc0-a0a31a9c89fd@kernel.org> <87fr93ky5i.ritesh.list@gmail.com> <16fef7a5-6853-4a6f-8d27-e005fa351eb7@linux.ibm.com> From: "David Hildenbrand (Red Hat)" Content-Language: en-US In-Reply-To: <16fef7a5-6853-4a6f-8d27-e005fa351eb7@linux.ibm.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 12/22/25 06:57, Sourabh Jain wrote: > > > On 22/12/25 08:42, Ritesh Harjani (IBM) wrote: >> "David Hildenbrand (Red Hat)" writes: >> >>>> Coming back to the fixes tag. I did mention a bit of a history [2] of >>>> whatever I could find while reviewing this patch. I am not sure whether >>>> you have looked into the links shared in that email or not. Here [2]: >>>> >>>> [2]: https://lore.kernel.org/linuxppc-dev/875xa3ksz9.ritesh.list@gmail.com/ >>>> >>>> Where I am coming from is.. The current patch is acutally a partial >>>> revert of the patch mentioned in the fixes tag. That means if this patch >>>> gets applied to the older stable kernels, it would end up bringing the >>>> same problem back, which the "Fixes" tagged patch is fixing in the 1st >>>> place, isnt' it? See this discussion [3]... >>>> >>>> [3]: https://lore.kernel.org/all/b1f04f9f-fa46-c2a0-7693-4a0679d2a1ee@oracle.com/T/#m0eee87b458d93559426b8b0e78dc6ebcd26ad3ae >>>> >>>> ... So, IMO - the right fixes tag, if we have to add, it should be the >>>> patch which moved the hpage_shift initialization to happen early i.e. in >>>> mmu_early_init_devtree. That would be this patch [4]: >>>> >>>> [4]: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=2354ad252b66695be02f4acd18e37bf6264f0464 >>>> >>>> Now, it's not really that the patch [4] had any issue as such. But it >>>> seems like, that the current fix can only be applied after patch [4] is >>>> taken. >>>> >>>> Do we agree? >>> I think we should document all that in the cover letter, an describe >>> that this partial revert is only possible after [4], >> Yes, I agree. Let's add the above details in the commit msg. >> >>> and that that must >>> be considered when attempting any kind of stable backports. >> Sure. I would prefer if we change the Fixes tag to the one which I >> pointed in above [4] (with explaination in the commit msg). However I am >> still ok if we would like to retain the existing fixes tag and show [4] >> as a dependency. > > I think we should keep the current Fixes tag with an explanation for > dependency > on [1] in the commit message. > > Would anyone have a different view? Whatever introduced the issue should be called out in the Fixes tag; if there are dependencies for the fix through other patches that were already merged, that can be documented in the patch description (relevant for stable or distro backports only). -- Cheers David