From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ej1-f46.google.com (mail-ej1-f46.google.com [209.85.218.46]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D008EDDAD; Fri, 8 Aug 2025 03:40:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.218.46 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754624429; cv=none; b=ZHTDhynEGwl3cD/e0fFmjQ947TUaZ1LCO8k+OJDzK8+hzzEQGYPfLi7+txe+K06aeDr1Gw/lRYQCOL4fdtK0vmc4eoj8nj9IRNgP2RqwjavgOPHhP5+mCofvhuKQvFfSjVmm17PiauZtbVoI7di71HnPaaf4MeIPKRYs7uref7Y= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754624429; c=relaxed/simple; bh=vPtGs1H6VkSKXEpEOKQdx0uKSIef9i2bCqdRYgqi/OQ=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=rwJ7+CQVHpr2bhczb3jbHMW8SLxDMP+XEdtyuXRsFXEtU+NYHW9iZFyh6gmzoAy/wjno5g7sNDiBAA5ciNtBP1rHI5nigVzriMN9zfU2y73atiOlftscQhUD+gEDAPPYLUQZY1hc2crj9ijgrtKjYsGD+RIufsH8YwtaPKQXDkA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=AvzjlbRi; arc=none smtp.client-ip=209.85.218.46 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="AvzjlbRi" Received: by mail-ej1-f46.google.com with SMTP id a640c23a62f3a-ae9c2754a00so333515266b.2; Thu, 07 Aug 2025 20:40:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1754624426; x=1755229226; darn=vger.kernel.org; h=user-agent:in-reply-to:content-disposition:mime-version:references :reply-to:message-id:subject:cc:to:from:date:from:to:cc:subject:date :message-id:reply-to; bh=3VwJdv2/aTZlGvHmbtM9UzrCVsyM+3NNVAJCeNgjzdo=; b=AvzjlbRiFhGjdr6sBKnjTzOLMecOiZVeIujRoyPK9I/OufFI2mdtWztbvnlwP9yab6 cpwceJpVD83CkXg2f4N6uX7TXwMWyVtAx4ck5tmpEq/DWwNheD05GleQGFu00vT7Gkjv bIj2puNae2ZeVQVk09CnSpo2y35VtI4nPyQHkAoYTlaH2CzPy1EPYbX1pWkQU37ZF1uK Bgk2Cl8Tk6f00QiHNdnMbyUC1XmENh5HULF7aE2X6mHSItSD+Sx6VYhU4uGuilwsHFgk Rr+UBIy3iuvINYxkPfiOZ7QufRr+To4Na6U6h/JzkCvdA1KXZW9PWoZ5A8AUJvpvT5xm WeAQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1754624426; x=1755229226; h=user-agent:in-reply-to:content-disposition:mime-version:references :reply-to:message-id:subject:cc:to:from:date:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to; bh=3VwJdv2/aTZlGvHmbtM9UzrCVsyM+3NNVAJCeNgjzdo=; b=C/06YYzryrO2zzGYnv+abdNVhXmIdXJuWvXfv4R6FUG//HngvSGt9/AH2xjZNX7taG 6vku8cdTbbxpg2u8/idx1arohEk/Zm6zETUlb6PviCn3NO9wbIuykA9k/MsgzXMuxUcC meYU150tceI3UJtPw/9+xvqUlgNwchhxZc/Fui0laESI45GmnmzQMnflS+laMx2UpnJX 37Ix+djm3KdDjbKw+sHY3qz5j998Zco92NVye5T3RLrRoT4ZNQZuQzr2CM1g7k+jvUHS luqxIMKYz9NdqaAABW3IYKvS8E+RTogDoKr5NmL+0XsgksN4LmRKmEdlGe3UghUoRrpg SdbA== X-Forwarded-Encrypted: i=1; AJvYcCUxfU6vugwwf57gOZrbDUNabeIOzsD5oHn6NL2YRbiIZ3FzEAXfizBkuHOynhZWglM6Tma+/1X9GiFanQ==@vger.kernel.org, AJvYcCVdCpiKp5sNSuYpPe9WDoLulrpyLdaXhp+hxaUtKHYCnvW/hYT13OgFUURrakX50J8wTXpa4MUTsbHQw6k=@vger.kernel.org X-Gm-Message-State: AOJu0YwGhDyargg7LFRd6BteDZ/k3ZVY8g4FwPOrIxAoM3lJ+vAKl7UM Pc7h02H4Y2KtrA45g8YOKmOaICVfvps6TcbN54HXwCiXXZM+rYlWxNmx X-Gm-Gg: ASbGnctyvqnm5PjfetCpF+ShMhXiDL78Bx4uYqlQdihjq5BVsbdXIVw1kR4AZJfOCg2 Qm7HSdGgex/QLix9X3qDvqpFyafH+UJGbAED3FpqHvUb24akBTth2EtN5fuXFLYLs/6XtSSQj8j afBh5MAsRMuhZ6Zinv4lJIX4taE8PdYEP+b5THOtAYsYBLY5fointN0F1ch7PRuNZGFl5MK6OkU HGrHy9am3PBrcMK2DDvdCx5S7Og31ufGEmx02vfUI+p0RIn4l11LaUrkS8ewL8Ditboh1XO2Mfu oKKNaCFbuCg9HshAMEUWxi3SBx75cX1WqKdhPpbTyrfprpdKBdl8KFiuotKQwJqcgfY02illwj/ +HnvXBQiLEXiU8xtjdFn87A== X-Google-Smtp-Source: AGHT+IHtPlYQF9NDTtoDpiah0Zgc7+o2I8oA3L3L8/8DtlWIli216aBTAesdtybo8gOA0RWRG7TehQ== X-Received: by 2002:a17:907:1c22:b0:af9:71c2:9f7 with SMTP id a640c23a62f3a-af9c63b0ca7mr102202366b.2.1754624426029; Thu, 07 Aug 2025 20:40:26 -0700 (PDT) Received: from localhost ([185.92.221.13]) by smtp.gmail.com with ESMTPSA id a640c23a62f3a-af91a07659dsm1405214566b.21.2025.08.07.20.40.25 (version=TLS1_2 cipher=ECDHE-ECDSA-CHACHA20-POLY1305 bits=256/256); Thu, 07 Aug 2025 20:40:25 -0700 (PDT) Date: Fri, 8 Aug 2025 03:40:25 +0000 From: Wei Yang To: Sumanth Korikkar Cc: Andrew Morton , linux-mm , LKML , David Hildenbrand , richard.weiyang@gmail.com, Gerald Schaefer , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , linux-s390 Subject: Re: [PATCH v4] mm: fix accounting of memmap pages Message-ID: <20250808034025.bh5giuozvz7ri34m@master> Reply-To: Wei Yang References: <20250807183545.1424509-1-sumanthk@linux.ibm.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250807183545.1424509-1-sumanthk@linux.ibm.com> User-Agent: NeoMutt/20170113 (1.7.2) On Thu, Aug 07, 2025 at 08:35:45PM +0200, Sumanth Korikkar wrote: >For !CONFIG_SPARSEMEM_VMEMMAP, memmap page accounting is currently done >upfront in sparse_buffer_init(). However, sparse_buffer_alloc() may >return NULL in failure scenario. > >Also, memmap pages may be allocated either from the memblock allocator >during early boot or from the buddy allocator. When removed via >arch_remove_memory(), accounting of memmap pages must reflect the >original allocation source. > >To ensure correctness: >* Account memmap pages after successful allocation in sparse_init_nid() > and section_activate(). >* Account memmap pages in section_deactivate() based on allocation > source. > >Cc: stable@vger.kernel.org >Fixes: 15995a352474 ("mm: report per-page metadata information") >Suggested-by: David Hildenbrand >Signed-off-by: Sumanth Korikkar LGTM Reviewed-by: Wei Yang -- Wei Yang Help you, Help me