From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) (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 234A52116E6; Fri, 10 Jan 2025 14:47:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=148.163.156.1 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736520442; cv=none; b=oMZhVj7ivGM6y6Ya3TK2d7lFESp4JdoIHgmp3KL9AnmI6wUILG8oSmWGpZU+SYUlhZWm5jtbQtaeGgPY/DnAQyF2XPjgX14fnb5I58xo3QgIPeOxmyReFC65vJC/GD5+lkoJmrwK0kiwoKKet18P2qNOh4BwS/WVfsvR4lvEF1I= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736520442; c=relaxed/simple; bh=Nwi9x0KRVUX+HhVnzQQfUW3EJ1pjbVFPSiqj41R7hP8=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=sjg+Ka0jcbfUoubFr8CHtXJ+Kf56mMLQnMIxiE8ptpsTw8WYBzNV34Jx4Y1eXIawxPEWa45HudDY8/WOufiTRPiR2diQFgcemPpdlDr6oN9B1McuhsjYHH4sfarJN8ISYVWoOoXGjnIg4k77Ncr/CHX6I80/DzVS8t2OmGzBnVA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.ibm.com; spf=pass smtp.mailfrom=linux.ibm.com; dkim=pass (2048-bit key) header.d=ibm.com header.i=@ibm.com header.b=PLTC+5mR; arc=none smtp.client-ip=148.163.156.1 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.ibm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.ibm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=ibm.com header.i=@ibm.com header.b="PLTC+5mR" Received: from pps.filterd (m0360083.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.18.1.2/8.18.1.2) with ESMTP id 50AEIQus015062; Fri, 10 Jan 2025 14:47:01 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=cc :content-transfer-encoding:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to; s=pp1; bh=ZYbwep TLCOiqF08Tk1K3/9sm1ogW5I4vbVOfFlCfgEM=; b=PLTC+5mR8TgHXUM5beLlTc MI3pCmMBveC/9qyZBMi1TP/1TkmEQ9E6RsddpbLPjL/2R1vLEQ3V5xMj1M4SRiin GADEeS8p2xdHcqGlzGSzb06zzT6/BFVw8iVZvNSCZUGuTs2h/8VU7kc46pXmLDiF qY5yo6950fzySAgGiivynWaoniwZAa8+yf6Bk5cP5Kmw7mYPsjJnzga1yQdVCSsQ 87ueJbwqZn6ZIS2xDpeCKuC4mWRSl2mrE3PBmGsyExlNprtKOvLMrM7MsoTcuFh6 7LQOwLzPJkg/51zKKvdVdH2aQ+wmTUgnWpLBFujjMVxheC1ytFzvyOkIG3oH2kXQ == Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 442v1bthgq-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 10 Jan 2025 14:47:01 +0000 (GMT) Received: from m0360083.ppops.net (m0360083.ppops.net [127.0.0.1]) by pps.reinject (8.18.0.8/8.18.0.8) with ESMTP id 50AEl0Qn009482; Fri, 10 Jan 2025 14:47:00 GMT Received: from ppma21.wdc07v.mail.ibm.com (5b.69.3da9.ip4.static.sl-reverse.com [169.61.105.91]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 442v1bthgk-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 10 Jan 2025 14:47:00 +0000 (GMT) Received: from pps.filterd (ppma21.wdc07v.mail.ibm.com [127.0.0.1]) by ppma21.wdc07v.mail.ibm.com (8.18.1.2/8.18.1.2) with ESMTP id 50ADgCSV013571; Fri, 10 Jan 2025 14:46:59 GMT Received: from smtprelay06.dal12v.mail.ibm.com ([172.16.1.8]) by ppma21.wdc07v.mail.ibm.com (PPS) with ESMTPS id 43ygapanrh-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 10 Jan 2025 14:46:59 +0000 Received: from smtpav02.dal12v.mail.ibm.com (smtpav02.dal12v.mail.ibm.com [10.241.53.101]) by smtprelay06.dal12v.mail.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 50AEkwSv30868148 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 10 Jan 2025 14:46:58 GMT Received: from smtpav02.dal12v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 0DF785805A; Fri, 10 Jan 2025 14:46:58 +0000 (GMT) Received: from smtpav02.dal12v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 8DE8758051; Fri, 10 Jan 2025 14:46:55 +0000 (GMT) Received: from [9.171.42.47] (unknown [9.171.42.47]) by smtpav02.dal12v.mail.ibm.com (Postfix) with ESMTPS; Fri, 10 Jan 2025 14:46:55 +0000 (GMT) Message-ID: Date: Fri, 10 Jan 2025 15:46:55 +0100 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] rhashtable: Fix potential deadlock by moving schedule_work outside lock To: Herbert Xu , Breno Leitao Cc: Michael Kelley , "saeedm@nvidia.com" , "tariqt@nvidia.com" , "linux-hyperv@vger.kernel.org" , Andrew Morton , Thomas Graf , Tejun Heo , Hao Luo , Josh Don , Barret Rhoden , "netdev@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Heiko Carstens , Alexander Gordeev References: <20241128-scx_lockdep-v1-1-2315b813b36b@debian.org> <20250102-daffy-vanilla-boar-6e1a61@leitao> <20250109-marigold-bandicoot-of-exercise-8ebede@leitao> Content-Language: en-US From: Zaslonko Mikhail In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 X-Proofpoint-ORIG-GUID: kham6myY7StHcU36gligKTUdQpQnBn5d X-Proofpoint-GUID: 1vmhUAfWMifC2MPi-Y80M2IerHttMSQo X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1051,Hydra:6.0.680,FMLib:17.12.62.30 definitions=2024-10-15_01,2024-10-11_01,2024-09-30_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 mlxlogscore=999 malwarescore=0 spamscore=0 clxscore=1011 impostorscore=0 phishscore=0 lowpriorityscore=0 bulkscore=0 priorityscore=1501 suspectscore=0 adultscore=0 mlxscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.19.0-2411120000 definitions=main-2501100114 Herbert and Breno, On 10.01.2025 10:27, Herbert Xu wrote: > On Thu, Jan 09, 2025 at 02:15:17AM -0800, Breno Leitao wrote: > > Reported-by: Michael Kelley > Fixes: e1d3422c95f0 ("rhashtable: Fix potential deadlock by moving schedule_work outside lock") > Signed-off-by: Herbert Xu > > diff --git a/lib/rhashtable.c b/lib/rhashtable.c > index bf956b85455a..e196b6f0e35a 100644 > --- a/lib/rhashtable.c > +++ b/lib/rhashtable.c > @@ -621,7 +621,7 @@ static void *rhashtable_try_insert(struct rhashtable *ht, const void *key, > > rht_unlock(tbl, bkt, flags); > > - if (PTR_ERR(data) == -ENOENT && !new_tbl) { > + if (!new_tbl) { > atomic_inc(&ht->nelems); > if (rht_grow_above_75(ht, tbl)) > schedule_work(&ht->run_work); I'd like to let you know that I was getting OOM failure on s390 when booting the kernel (linux-next20250109) with limited memory (mem=1G kernel parameter). Problem took place in both zVM and LPAR environments. Bisecting also revealed the commit e1d3422c95f0 ("rhashtable: Fix potential deadlock by moving schedule_work outside lock"). Afterwards, I tried the fix from Herbert above and the error does not appear any more. So it seems to resolve the issue. Thanks, Mikhail