lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Wed, 17 Nov 2010 16:09:12 +0800 From: "Xin, Xiaohui" <xiaohui.xin@...el.com> To: "Xin, Xiaohui" <xiaohui.xin@...el.com>, David Miller <davem@...emloft.net> CC: "netdev@...r.kernel.org" <netdev@...r.kernel.org>, "kvm@...r.kernel.org" <kvm@...r.kernel.org>, "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>, "mst@...hat.com" <mst@...hat.com>, "mingo@...e.hu" <mingo@...e.hu>, "herbert@...dor.apana.org.au" <herbert@...dor.apana.org.au>, "jdike@...ux.intel.com" <jdike@...ux.intel.com> Subject: RE: [PATCH v15 00/17] Provide a zero-copy method on KVM virtio-net. >-----Original Message----- >From: kvm-owner@...r.kernel.org [mailto:kvm-owner@...r.kernel.org] On Behalf Of Xin, >Xiaohui >Sent: Thursday, November 11, 2010 4:28 PM >To: David Miller >Cc: netdev@...r.kernel.org; kvm@...r.kernel.org; linux-kernel@...r.kernel.org; >mst@...hat.com; mingo@...e.hu; herbert@...dor.apana.org.au; jdike@...ux.intel.com >Subject: RE: [PATCH v15 00/17] Provide a zero-copy method on KVM virtio-net. > >>-----Original Message----- >>From: David Miller [mailto:davem@...emloft.net] >>Sent: Thursday, November 11, 2010 1:47 AM >>To: Xin, Xiaohui >>Cc: netdev@...r.kernel.org; kvm@...r.kernel.org; linux-kernel@...r.kernel.org; >>mst@...hat.com; mingo@...e.hu; herbert@...dor.apana.org.au; jdike@...ux.intel.com >>Subject: Re: [PATCH v15 00/17] Provide a zero-copy method on KVM virtio-net. >> >>From: xiaohui.xin@...el.com >>Date: Wed, 10 Nov 2010 17:23:28 +0800 >> >>> From: Xin Xiaohui <xiaohui.xin@...el.com> >>> >>>>2) The idea to key off of skb->dev in skb_release_data() is >>>> fundamentally flawed since many actions can change skb->dev on you, >>>> which will end up causing a leak of your external data areas. >>> >>> How about this one? If the destructor_arg is not a good candidate, >>> then I have to add an apparent field in shinfo. >> >>If destructor_arg is actually a net_device pointer or similar, >>you will need to take a reference count on it or similar. >> >Do you mean destructor_arg will be consumed by other user? >If that case, may I add a new structure member in shinfo? >Thus only zero-copy will use it, and no need for the reference count. > How about this? It really needs somewhere to track the external data area, and if something wrong with it, we can also release the data area. We think skb_release_data() is the right place to deal with it. If I understood right, that destructor_arg will be used by other else that why reference count is needed, then how about add a new structure member in shinfo? Thanks Xiaohui >>Which means --> good bye performance especially on SMP. >> >>You're going to be adding new serialization points and at >>least two new atomics per packet. >-- >To unsubscribe from this list: send the line "unsubscribe kvm" in >the body of a message to majordomo@...r.kernel.org >More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Powered by blists - more mailing lists