From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-lb0-f198.google.com (mail-lb0-f198.google.com [209.85.217.198]) by kanga.kvack.org (Postfix) with ESMTP id A40D16B0253 for ; Mon, 23 May 2016 17:36:06 -0400 (EDT) Received: by mail-lb0-f198.google.com with SMTP id q17so18655628lbn.3 for ; Mon, 23 May 2016 14:36:06 -0700 (PDT) Received: from emh03.mail.saunalahti.fi (emh03.mail.saunalahti.fi. [62.142.5.109]) by mx.google.com with ESMTPS id jd5si15428696lbc.59.2016.05.23.14.36.05 for (version=TLS1 cipher=AES128-SHA bits=128/128); Mon, 23 May 2016 14:36:05 -0700 (PDT) Date: Tue, 24 May 2016 00:36:04 +0300 From: Aaro Koskinen Subject: Re: __napi_alloc_skb failures locking up the box Message-ID: <20160523213604.GB1253@raspberrypi.musicnaut.iki.fi> References: <20160430192402.GA8366@raspberrypi.musicnaut.iki.fi> <1462046052.5535.190.camel@edumazet-glaptop3.roam.corp.google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1462046052.5535.190.camel@edumazet-glaptop3.roam.corp.google.com> Sender: owner-linux-mm@kvack.org List-ID: To: Eric Dumazet Cc: "David S. Miller" , netdev@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Hi, On Sat, Apr 30, 2016 at 12:54:12PM -0700, Eric Dumazet wrote: > On Sat, 2016-04-30 at 22:24 +0300, Aaro Koskinen wrote: > > Hi, > > > > I have old NAS box (Thecus N2100) with 512 MB RAM, where rsync from NFS -> > > disk reliably results in temporary out-of-memory conditions. > > > > When this happens the dmesg gets flooded with below logs. If the serial > > console logging is enabled, this will lock up the box completely and > > the backup is not making any progress. > > > > Shouldn't these allocation failures be ratelimited somehow (or even made > > silent)? It doesn't sound right if I can lock up the system simply by > > copying files... > > Agreed. > > All napi_alloc_skb() callers handle failure just fine. > > If they did not, a NULL deref would produce a proper stack dump. > > When memory gets this tight, other traces will be dumped anyway. > > diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h > index 15d0df943466..0652709fe81a 100644 > --- a/include/linux/skbuff.h > +++ b/include/linux/skbuff.h > @@ -2423,7 +2423,7 @@ struct sk_buff *__napi_alloc_skb(struct napi_struct *napi, > static inline struct sk_buff *napi_alloc_skb(struct napi_struct *napi, > unsigned int length) > { > - return __napi_alloc_skb(napi, length, GFP_ATOMIC); > + return __napi_alloc_skb(napi, length, GFP_ATOMIC | __GFP_NOWARN); > } > void napi_consume_skb(struct sk_buff *skb, int budget); Care to send this as a formal patch, so I can reply with my Tested-by? A. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org