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 4BB72346ACE; Tue, 4 Aug 2026 08:44:56 +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=1785833097; cv=none; b=C+xIqaq77OWcFdaoVbT219PRWhrpFNdGgm6OPIAv5UsEuEiwsPQ8YBsGlr3kF+pf6Ea0Hig8uU2KNLKTtNjda43CTUNFcUX/BqYZltcbqGzF4hXxAs4UPk1kHIYA7qgEe9eGJx/gHCfQoqPA4jS6jBE0MqtprXbdS/lRiqm0Szw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785833097; c=relaxed/simple; bh=E/SQ+ZQlx0Gt56FBg5RSYpdotMb8gG8qyAcF6wQlu+A=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=K8RW9HnYq1RJ77xRLfO0mVhU4vf0Zau70kZlqxUwkIou3KYwV080XPqYizs8K8Obxe/4f0zjxg/DBubxbxPZQGONFGZTtB9n3YcOHposbJzRl9sksdouXM9LjM6k4yxJWVAEFCmSOqFp6dau7aESXxQojP7UV/jdSHTgU9nnShU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=h8k+K4wN; 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="h8k+K4wN" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4CC981F000E9; Tue, 4 Aug 2026 08:44:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1785833095; bh=5H6RJSZDPSmwbooABTk+unARmGwOSegsfChkBx3+G1g=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=h8k+K4wNBTRdXo0xOJL7GudQvyhO97L1Z7liu2PElWNyNmQxZ3o42v1nrg/Ro9Vep HOKlYdjwlztIsnXCz/fKGtOK9xpJdfdnKuqe6jGfA5TRdtM73MRRLRLP8a3P4w4m8K RcWDgBC6FHuoLj7qYHcT4hVIgZ8DZM4wT021eCwJSRa8Azos+G9gya2TQsALvZPyj4 ClNFr71IkNtyEo+R4o24mE2ZFHhLRjBuAZ0RpdxS+iy6LtG2J4724c5umY/iviQPD6 RaS/maiEVIFSUOfF0rhQUlysuhu1Qy730NTecch8yCKTv40kCJnUNSiMwix+whG/5I bcvwepCNYY8Ag== Message-ID: <2827aefd-30f6-424d-8bf5-aa46b97ee5eb@kernel.org> Date: Tue, 4 Aug 2026 10:44:51 +0200 Precedence: bulk X-Mailing-List: linux-next@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: linux-next: manual merge of the slab tree with the rcu tree Content-Language: en-US To: Alice Ryhl , Nathan Chancellor Cc: Boqun Feng , Miguel Ojeda , broonie@kernel.org, harry@kernel.org, linux-kernel@vger.kernel.org, linux-next@vger.kernel.org, paulmck@kernel.org, puranjay@kernel.org, Greg Kroah-Hartman , Bert Karwatzki , Gary Guo References: <20260731075644.20215-1-ojeda@kernel.org> <20260731220137.GA3307698@ax162> From: "Vlastimil Babka (SUSE)" Autocrypt: addr=vbabka@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 8/4/26 10:26, Alice Ryhl wrote: > On Fri, Jul 31, 2026 at 03:01:37PM -0700, Nathan Chancellor wrote: >> On Fri, Jul 31, 2026 at 11:14:42PM +0200, Alice Ryhl wrote: >> > I like Nathan's fix as well. >> > >> > Not sure if it needs to be done in the merge commit, or if we can >> > apply it as a patch to char-misc despite the unknown CFG_*? >> >> It would need to be applied at the merge of the two trees because >> CONFIG_KVFREE_RCU_BATCHED was introduced back in 6.15 in commit >> c9f8f1242a4c ("slab: don't batch kvfree_rcu() with SLUB_TINY"). > > Is that required? Yes, the cfg(CONFIG_KVFREE_RCU_BATCHED) will fail in > Greg's tree because the CFG doesn't exist and is hence not enabled ... > but the cfg not applying is what we want. But it does exist, CONFIG_KVFREE_RCU_BATCHED itself is old. What's new in slab tree is kvfree_call_rcu() taking a "struct kvfree_rcu_head *" parameter instead of "struct rcu_head *head" (which is actually "callback_head"). With Gary's suggestion [1] CONFIG_KVFREE_RCU_BATCHED will go out of the picture completely anyway. What remains is an unconditional change of the parameter. Can it be "resolved in advance" or only in the merge commit? https://lore.kernel.org/all/11a8bf75-8fc1-4d32-a350-6bf8156dd8ab@kernel.org/ > The main risk I can think of is a warning about an unknown CFG being > used. Perhaps we could silence the warning? > > Or I mean, we can also just fix it in the merge commit if that works for > everyone. > > Alice