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 567A52C234E; Wed, 1 Jul 2026 08:35:46 +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=1782894947; cv=none; b=XYaF8BRevgw5kEFAoPeEgOQnBvk9s7e4jCpnKSneycfd83+U+Yu/SU08VGKkjqL4XvC2SqEiiEq7wHrNiywJCmNlHd/YdDH3z1zHUtsuUK9+3hnraLbGDtC3yTH1eqZoekicoh/q1oKZRdlcH/I0iSgjFClm4J8LtSMn4BTfghQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782894947; c=relaxed/simple; bh=3tdFv4J6APyxP2F+HZI/lqz5Mwl1k01vkJ8j9eZfRWI=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=Bet9peXS+sMvSy/0bA8Ez6nt65Wp0i+WzNVjSqRUB6JZS5Xr5n/nz3DgeOm1ZH5d0UeAfBl/xt6SzseWO+lFrrMbPJ4oRFmUvLPHHGW2VpCHu0rYZ9dT5kR4rUdGS6CYfFj/igWsiCLw4igL7TPOXb/Rl6s1sPSaKtfa0cNokOs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=CUbiQPlR; 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="CUbiQPlR" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CA6C21F00A3A; Wed, 1 Jul 2026 08:35:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1782894946; bh=JrfIlvjinRp/Isc/2aqvA7fk3pmFV0oszkJp6lh7LfY=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=CUbiQPlRNLrGAaISfsMY2lKId+9XnZt02rpJWrZt0iiXTBPY5ps7EvIeCm49fjIVC QTGVocVVcGV1jQbSkMvGtW692LfGFij4mHu5VN1jur1x+xpTGe4z7ZNYrUsR49ViUR oTJfADXQm1srqI0ZrACTDBgaizDXw2H4x68GvqMOPa7GpXhf6dBxFUQVHYbSbS0Ocg Kr2xS3Er8g52fpOCoxyesm6VGfy3j+i4inOa8JNrwyIvK8Yn6oBXcWw853SY+z+Q88 7eKpSTwmSHMy0+w/aTGBKIPE4lo+L2QC9aiKrHpMkBGPfccrQQP7niAIhFOWDwoztW a7g0HvZ7xRLdQ== Message-ID: Date: Wed, 1 Jul 2026 10:35:41 +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/mm_init: handle alloc_percpu failure in free_area_init_core_hotplug To: Gregory Price , linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, linux-cxl@vger.kernel.org, kernel-team@meta.com, osalvador@suse.de, akpm@linux-foundation.org, rppt@kernel.org, mgorman@techsingularity.net, hannes@cmpxchg.org, vbabka@kernel.org References: <20260630214039.2263562-1-gourry@gourry.net> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit > * The node we allocated has no zone fallback lists. For avoiding > diff --git a/mm/mm_init.c b/mm/mm_init.c > index 306ea5c13f54..37fd64ce144d 100644 > --- a/mm/mm_init.c > +++ b/mm/mm_init.c > @@ -1536,7 +1536,7 @@ void __init set_pageblock_order(void) > * NOTE: this function is only called during memory hotplug > */ > #ifdef CONFIG_MEMORY_HOTPLUG > -void __ref free_area_init_core_hotplug(struct pglist_data *pgdat) > +int __ref free_area_init_core_hotplug(struct pglist_data *pgdat) > { > int nid = pgdat->node_id; > enum zone_type z; > @@ -1544,8 +1544,14 @@ void __ref free_area_init_core_hotplug(struct pglist_data *pgdat) > > pgdat_init_internals(pgdat); > > - if (pgdat->per_cpu_nodestats == &boot_nodestats) > - pgdat->per_cpu_nodestats = alloc_percpu(struct per_cpu_nodestat); > + if (pgdat->per_cpu_nodestats == &boot_nodestats) { > + struct per_cpu_nodestat __percpu *p; > + > + p = alloc_percpu(struct per_cpu_nodestat); > + if (!p) > + return -ENOMEM; > + pgdat->per_cpu_nodestats = p; Is there a need for the temporary variable? Also how to handle cleanup on error? Or why can we skip cleanup? (what happens if we get another call to __try_online_node() later?) -- Cheers, David