From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out30-131.freemail.mail.aliyun.com (out30-131.freemail.mail.aliyun.com [115.124.30.131]) (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 38DB525614; Mon, 19 Feb 2024 09:54:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=115.124.30.131 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1708336484; cv=none; b=WKOekneIpiJUa8zEFif7A6VZj2IHyejE62RyivaLbSYStWD28Bfo74y9+s5oFjqCm9cFZ/ShZHz0StNLbWzxnF1xhdkfyJ5pnv6RPKxc/PX/Qz5N0aoxBOTxnRmTmbCTckG8CjBAT5snwjd8Gyb0lgqqSa37ofFQC6PqCLZ9ps4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1708336484; c=relaxed/simple; bh=2PGHb0YK6zNzLpgmDozQJqP4grk2DdHx3T5vOsHWuqg=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=dN5DFuCH+2SPV2Wm9VFXzTDfT6AVzoCLyAL9LrOWC6iB/XELCSzSUMY/LPqpuDhHJj2TFvjK0ZV2LSFrONzFGLNsU0LvMr38lRAVW98Rknj+QLFc+iGdNH0Pv28I1/Z5mMOajwZshsKZzopNUnQGULbGa78yuurAdvvL/JZtyIE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com; spf=pass smtp.mailfrom=linux.alibaba.com; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b=cJVJhjkM; arc=none smtp.client-ip=115.124.30.131 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b="cJVJhjkM" DKIM-Signature:v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1708336479; h=Message-ID:Date:MIME-Version:Subject:To:From:Content-Type; bh=HjH7v7MwvWWsSPBnkhGSwPRvi6ZG5EixZmbA5olhbF8=; b=cJVJhjkMFc3/SgYQ5niz4Vqd0l0S7c6Bt+wDTOKDZ80IP5Yn0WA0Cg5q6YgfscolA3eCof5yPsHqECoqSxmUDOoNm5Edc9Vaax3M32e8ZCcN8e63ARlxPnsJfieIIgSDH6x04NNsK/PtPaRZ5i9mjafUA6esGWagQW5jaqg/45c= X-Alimail-AntiSpam:AC=PASS;BC=-1|-1;BR=01201311R201e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018045192;MF=baolin.wang@linux.alibaba.com;NM=1;PH=DS;RN=9;SR=0;TI=SMTPD_---0W0sB01V_1708336477; Received: from 30.97.56.48(mailfrom:baolin.wang@linux.alibaba.com fp:SMTPD_---0W0sB01V_1708336477) by smtp.aliyun-inc.com; Mon, 19 Feb 2024 17:54:38 +0800 Message-ID: Date: Mon, 19 Feb 2024 17:54:36 +0800 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/vmscan: Fix a bug calling wakeup_kswapd() with a wrong zone index To: Oscar Salvador Cc: Byungchul Park , akpm@linux-foundation.org, ying.huang@intel.com, hannes@cmpxchg.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, kernel_team@skhynix.com, stable@vger.kernel.org References: <20240216111502.79759-1-byungchul@sk.com> <517e58d4-7537-4d9f-8893-0130c65c3fdb@linux.alibaba.com> From: Baolin Wang In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit On 2024/2/19 16:11, Oscar Salvador wrote: > On Mon, Feb 19, 2024 at 02:25:11PM +0800, Baolin Wang wrote: >> This means that there is no memory on the target node？ if so, we can add a >> check at the beginning to avoid calling unnecessary >> migrate_misplaced_folio(). >> >> diff --git a/mm/memory.c b/mm/memory.c >> index e95503d7544e..a64a1aac463f 100644 >> --- a/mm/memory.c >> +++ b/mm/memory.c >> @@ -5182,7 +5182,7 @@ static vm_fault_t do_numa_page(struct vm_fault *vmf) >> else >> last_cpupid = folio_last_cpupid(folio); >> target_nid = numa_migrate_prep(folio, vma, vmf->address, nid, >> &flags); >> - if (target_nid == NUMA_NO_NODE) { >> + if (target_nid == NUMA_NO_NODE || !node_state(target_nid, N_MEMORY)) >> { >> folio_put(folio); >> goto out_map; >> } >> >> (similar changes for do_huge_pmd_numa_page()) > > With the check in place from [1], numa_migrate_prep() will also return > NUMA_NO_NODE, so no need for this one here. > > And I did not check, but I assume that do_huge_pmd_numa_page() also ends > up calling numa_migrate_prep(). > > [1] https://lore.kernel.org/lkml/20240219041920.1183-1-byungchul@sk.com/ Right. I missed this patch before. So with checking in should_numa_migrate_memory(), I guess current changes in numamigrate_isolate_folio() can also be dropped, it will never hit a memoryless node after the patch [1], no?