From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 888ECC5AD5A for ; Wed, 12 Aug 2026 10:59:06 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 5A2AE6B00B8; Wed, 12 Aug 2026 06:59:05 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 579B66B00D2; Wed, 12 Aug 2026 06:59:05 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 48F5F6B00D6; Wed, 12 Aug 2026 06:59:05 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id 213946B00B8 for ; Wed, 12 Aug 2026 06:59:05 -0400 (EDT) Received: from smtpin20.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay05.hostedemail.com (Postfix) with ESMTP id A90704021F for ; Wed, 12 Aug 2026 10:59:04 +0000 (UTC) X-FDA: 85092320208.20.1185BBD Received: from tor.source.kernel.org (tor.source.kernel.org [172.105.4.254]) by imf13.hostedemail.com (Postfix) with ESMTP id F30DB20005 for ; Wed, 12 Aug 2026 10:59:02 +0000 (UTC) Authentication-Results: imf13.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b="C4c/VyOS"; dmarc=pass (policy=quarantine) header.from=kernel.org; spf=pass (imf13.hostedemail.com: domain of david@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=david@kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1786532343; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=YVDEOvc21CteZ5TMBNcUHD+Aeyjv25kv7zM1vGXS/tI=; b=iqxPzbnYj0IVEeHS9NrzP1VObhmj4Vdo48r075CIJipImxzD52aZXq5knmsEXcQLFRaB55 nL0UfkEC/nTLQmL3yEXcTPPkfyJpZrfNzQsM3EdXQQdpJ2CVHjK2Buvehf4YB+uaEP1i1m YKu77fwDRe/tOoxIiC822W6nq1NR5no= ARC-Authentication-Results: i=1; imf13.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b="C4c/VyOS"; dmarc=pass (policy=quarantine) header.from=kernel.org; spf=pass (imf13.hostedemail.com: domain of david@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=david@kernel.org ARC-Seal: i=1; a=rsa-sha256; d=hostedemail.com; s=arc-20220608; cv=none; t=1786532343; b=pARgaskIaT1f6OOk89yERiKrInque1H9e3TO3ozD4w1u35+mN24gtawdS453Rmv6EKpMo+ H39T8ifv6HIZVefLQJHT3IDIwPCD2sZ3jFd6/JHAUQt+pN/c9vgcBqcnINQ/CgAp+bmkE9 6zc44X9BKUtkQoZ5mB4L4f3xL7HVGhk= Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by tor.source.kernel.org (Postfix) with ESMTP id 95FB760A7E; Wed, 12 Aug 2026 10:59:02 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6195C1F000E9; Wed, 12 Aug 2026 10:58:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1786532342; bh=YVDEOvc21CteZ5TMBNcUHD+Aeyjv25kv7zM1vGXS/tI=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=C4c/VyOSbx/e8pqmJX8RzB21kZ03+KBHnAksmzw6moWobIT7bciODydX+z36ca6hE 4FPD567diHVtHzyUyPHzONlNFx/Ug+YY6T5ec/VsHg4mBX7Ves2seh4q+gBRXBj6nV cwMzwbDP1l9k4GVtZNgtd5VoY9IRnLK/z2TNXVmHK4g8t4QqcbNcuqwOtTfcIRVGCA 6O3hFi6IXLBatCirocmQxsLeT+3+Acjo+2q7eGfULmmwwm5G80nU3Yw94bRjZtRbvm JACTkexpoadnBW4w//HQdIcHeXkOulYxBkOTnuMTPj8OM8P38QFPZZOyUENTvSXZ9d 0fhBKy9YM0zDA== Message-ID: Date: Wed, 12 Aug 2026 12:58:53 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 1/3] mm, swap: ratelimit bad swap entry reports in get_swap_device() To: Pedro Falcato Cc: Breno Leitao , Andrew Morton , Chris Li , Kairui Song , Kemeng Shi , Nhat Pham , Baoquan He , Barry Song , Youngjun Park , Lorenzo Stoakes , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Jann Horn , Hugh Dickins , Baolin Wang , Peter Xu , Johannes Weiner , Yosry Ahmed , Chengming Zhou , linux-mm@kvack.org, linux-kernel@vger.kernel.org, kernel-team@meta.com References: <20260810-swap-v1-0-375ef0767206@debian.org> <20260810-swap-v1-1-375ef0767206@debian.org> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; keydata= xsFNBFXLn5EBEAC+zYvAFJxCBY9Tr1xZgcESmxVNI/0ffzE/ZQOiHJl6mGkmA1R7/uUpiCjJ dBrn+lhhOYjjNefFQou6478faXE6o2AhmebqT4KiQoUQFV4R7y1KMEKoSyy8hQaK1umALTdL QZLQMzNE74ap+GDK0wnacPQFpcG1AE9RMq3aeErY5tujekBS32jfC/7AnH7I0v1v1TbbK3Gp XNeiN4QroO+5qaSr0ID2sz5jtBLRb15RMre27E1ImpaIv2Jw8NJgW0k/D1RyKCwaTsgRdwuK Kx/Y91XuSBdz0uOyU/S8kM1+ag0wvsGlpBVxRR/xw/E8M7TEwuCZQArqqTCmkG6HGcXFT0V9 PXFNNgV5jXMQRwU0O/ztJIQqsE5LsUomE//bLwzj9IVsaQpKDqW6TAPjcdBDPLHvriq7kGjt WhVhdl0qEYB8lkBEU7V2Yb+SYhmhpDrti9Fq1EsmhiHSkxJcGREoMK/63r9WLZYI3+4W2rAc UucZa4OT27U5ZISjNg3Ev0rxU5UH2/pT4wJCfxwocmqaRr6UYmrtZmND89X0KigoFD/XSeVv jwBRNjPAubK9/k5NoRrYqztM9W6sJqrH8+UWZ1Idd/DdmogJh0gNC0+N42Za9yBRURfIdKSb B3JfpUqcWwE7vUaYrHG1nw54pLUoPG6sAA7Mehl3nd4pZUALHwARAQABzS5EYXZpZCBIaWxk ZW5icmFuZCAoQ3VycmVudCkgPGRhdmlkQGtlcm5lbC5vcmc+wsGQBBMBCAA6AhsDBQkmWAik AgsJBBUKCQgCFgICHgUCF4AWIQQb2cqtc1xMOkYN/MpN3hD3AP+DWgUCaYJt/AIZAQAKCRBN 3hD3AP+DWriiD/9BLGEKG+N8L2AXhikJg6YmXom9ytRwPqDgpHpVg2xdhopoWdMRXjzOrIKD g4LSnFaKneQD0hZhoArEeamG5tyo32xoRsPwkbpIzL0OKSZ8G6mVbFGpjmyDLQCAxteXCLXz ZI0VbsuJKelYnKcXWOIndOrNRvE5eoOfTt2XfBnAapxMYY2IsV+qaUXlO63GgfIOg8RBaj7x 3NxkI3rV0SHhI4GU9K6jCvGghxeS1QX6L/XI9mfAYaIwGy5B68kF26piAVYv/QZDEVIpo3t7 /fjSpxKT8plJH6rhhR0epy8dWRHk3qT5tk2P85twasdloWtkMZ7FsCJRKWscm1BLpsDn6EQ4 jeMHECiY9kGKKi8dQpv3FRyo2QApZ49NNDbwcR0ZndK0XFo15iH708H5Qja/8TuXCwnPWAcJ DQoNIDFyaxe26Rx3ZwUkRALa3iPcVjE0//TrQ4KnFf+lMBSrS33xDDBfevW9+Dk6IISmDH1R HFq2jpkN+FX/PE8eVhV68B2DsAPZ5rUwyCKUXPTJ/irrCCmAAb5Jpv11S7hUSpqtM/6oVESC 3z/7CzrVtRODzLtNgV4r5EI+wAv/3PgJLlMwgJM90Fb3CB2IgbxhjvmB1WNdvXACVydx55V7 LPPKodSTF29rlnQAf9HLgCphuuSrrPn5VQDaYZl4N/7zc2wcWM7BTQRVy5+RARAA59fefSDR 9nMGCb9LbMX+TFAoIQo/wgP5XPyzLYakO+94GrgfZjfhdaxPXMsl2+o8jhp/hlIzG56taNdt VZtPp3ih1AgbR8rHgXw1xwOpuAd5lE1qNd54ndHuADO9a9A0vPimIes78Hi1/yy+ZEEvRkHk /kDa6F3AtTc1m4rbbOk2fiKzzsE9YXweFjQvl9p+AMw6qd/iC4lUk9g0+FQXNdRs+o4o6Qvy iOQJfGQ4UcBuOy1IrkJrd8qq5jet1fcM2j4QvsW8CLDWZS1L7kZ5gT5EycMKxUWb8LuRjxzZ 3QY1aQH2kkzn6acigU3HLtgFyV1gBNV44ehjgvJpRY2cC8VhanTx0dZ9mj1YKIky5N+C0f21 zvntBqcxV0+3p8MrxRRcgEtDZNav+xAoT3G0W4SahAaUTWXpsZoOecwtxi74CyneQNPTDjNg azHmvpdBVEfj7k3p4dmJp5i0U66Onmf6mMFpArvBRSMOKU9DlAzMi4IvhiNWjKVaIE2Se9BY FdKVAJaZq85P2y20ZBd08ILnKcj7XKZkLU5FkoA0udEBvQ0f9QLNyyy3DZMCQWcwRuj1m73D sq8DEFBdZ5eEkj1dCyx+t/ga6x2rHyc8Sl86oK1tvAkwBNsfKou3v+jP/l14a7DGBvrmlYjO 59o3t6inu6H7pt7OL6u6BQj7DoMAEQEAAcLBfAQYAQgAJgIbDBYhBBvZyq1zXEw6Rg38yk3e EPcA/4NaBQJonNqrBQkmWAihAAoJEE3eEPcA/4NaKtMQALAJ8PzprBEXbXcEXwDKQu+P/vts IfUb1UNMfMV76BicGa5NCZnJNQASDP/+bFg6O3gx5NbhHHPeaWz/VxlOmYHokHodOvtL0WCC 8A5PEP8tOk6029Z+J+xUcMrJClNVFpzVvOpb1lCbhjwAV465Hy+NUSbbUiRxdzNQtLtgZzOV Zw7jxUCs4UUZLQTCuBpFgb15bBxYZ/BL9MbzxPxvfUQIPbnzQMcqtpUs21CMK2PdfCh5c4gS sDci6D5/ZIBw94UQWmGpM/O1ilGXde2ZzzGYl64glmccD8e87OnEgKnH3FbnJnT4iJchtSvx yJNi1+t0+qDti4m88+/9IuPqCKb6Stl+s2dnLtJNrjXBGJtsQG/sRpqsJz5x1/2nPJSRMsx9 5YfqbdrJSOFXDzZ8/r82HgQEtUvlSXNaXCa95ez0UkOG7+bDm2b3s0XahBQeLVCH0mw3RAQg r7xDAYKIrAwfHHmMTnBQDPJwVqxJjVNr7yBic4yfzVWGCGNE4DnOW0vcIeoyhy9vnIa3w1uZ 3iyY2Nsd7JxfKu1PRhCGwXzRw5TlfEsoRI7V9A8isUCoqE2Dzh3FvYHVeX4Us+bRL/oqareJ CIFqgYMyvHj7Q06kTKmauOe4Nf0l0qEkIuIzfoLJ3qr5UyXc2hLtWyT9Ir+lYlX9efqh7mOY qIws/H2t In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Stat-Signature: uoubfazoq1c64py4i9wced5e6u8kqwi1 X-Rspamd-Queue-Id: F30DB20005 X-Rspamd-Server: rspam03 X-Rspam-User: X-HE-Tag: 1786532342-181524 X-HE-Meta: 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 GvFlANtp h6Ot7lA91axiEcpq4QMponvBVeCwODP2HNyW8ug0qTQwiybXLVegoKZNw8bq60NrcIcc2sK1NC9dxqTNS2nMHnc8yF+L/nmb1jI21b7BKEwuyFiYtb1cwAVh0ctmTIiQ0MvKgtmT24HYlC7j88UmDqUGBumw4z3ca9gO8+raeLNu9cfK6m0MveP9Lj1MLoerRi2wxcvij6Fu0iPtYPr/7T9nU12tGprVySNxP6eyzQS7Q3+22Hw2uC2y9aVZH74uNwZ7Db4oxFhYbALZjfYwk9MOu9cz6hGFXMphu2mI5MDamAmIlSSwdUmV6UtJAEJT0No8ZzIXjKRdObPJagd09JWnA1kgAeY67WaXB Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 8/11/26 18:48, Pedro Falcato wrote: > On Tue, Aug 11, 2026 at 05:33:54PM +0200, David Hildenbrand (Arm) wrote: >> On 8/10/26 18:26, Breno Leitao wrote: >>> A corrupt page table hands the same bogus entry to get_swap_device() on >>> every access to the mapping, and every rejection is logged. One machine >>> logged 6185620 copies of the same line in a few hours. >>> >>> Rate limit both prints. >>> >>> Signed-off-by: Breno Leitao >>> --- >>> mm/swapfile.c | 4 ++-- >>> 1 file changed, 2 insertions(+), 2 deletions(-) >>> >>> diff --git a/mm/swapfile.c b/mm/swapfile.c >>> index 4d4e3e3059f6b..9ab11dc24e4f1 100644 >>> --- a/mm/swapfile.c >>> +++ b/mm/swapfile.c >>> @@ -1899,11 +1899,11 @@ struct swap_info_struct *get_swap_device(swp_entry_t entry) >>> >>> return si; >>> bad_nofile: >>> - pr_err("%s: %s%08lx\n", __func__, Bad_file, entry.val); >>> + pr_err_ratelimited("%s: %s%08lx\n", __func__, Bad_file, entry.val); >>> out: >>> return NULL; >>> put_out: >>> - pr_err("%s: %s%08lx\n", __func__, Bad_offset, entry.val); >>> + pr_err_ratelimited("%s: %s%08lx\n", __func__, Bad_offset, entry.val); >>> percpu_ref_put(&si->users); >>> return NULL; >>> } >>> >> >> In print_bad_page_map() we use something more advanced >> (is_bad_page_map_ratelimited): essentially a burst of 60 followed by 1minute of >> silence. > > Is it more advanced? It just looks like a handcoded version of __ratelimit. > > ... I hate it now. I'll send a patch I guess. Thanks for cleaning that up! -- Cheers, David