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: Thu, 2 Sep 2010 08:50:34 +0800 From: Liang Li <liang.li@...driver.com> To: Ben Hutchings <bhutchings@...arflare.com> Cc: leoli@...escale.com, davem@...emloft.net, avorontsov@...mvista.com, netdev@...r.kernel.org, linuxppc-dev@...abs.org Subject: Re: [v1 PATCH] ucc_geth: fix ethtool set ring param bug On Wed, Sep 01, 2010 at 02:42:30PM +0100, Ben Hutchings wrote: > On Wed, 2010-09-01 at 09:43 +0800, Liang Li wrote: > > It's common sense that when we should do change to driver ring > > desc/buffer etc only after 'stop/shutdown' the device. When we > > do change while devices/driver is running, kernel oops occur: > [...] > > - ug_info->bdRingLenRx[queue] = ring->rx_pending; > > - ug_info->bdRingLenTx[queue] = ring->tx_pending; > > - > > if (netif_running(netdev)) { > > - /* FIXME: restart automatically */ > > - printk(KERN_INFO > > - "Please re-open the interface.\n"); > > + u16 rx_t; > > + u16 tx_t; > > + printk(KERN_INFO "Stopping interface %s.\n", netdev->name); > > + ucc_geth_close(netdev); > > + > > + rx_t = ug_info->bdRingLenRx[queue]; > > + tx_t = ug_info->bdRingLenTx[queue]; > > + > > + ug_info->bdRingLenRx[queue] = ring->rx_pending; > > + ug_info->bdRingLenTx[queue] = ring->tx_pending; > > + > > + printk(KERN_INFO "Reactivating interface %s.\n", netdev->name); > > + ret = ucc_geth_open(netdev); > > + if (ret) { > > + printk(KERN_WARNING "uec_set_ringparam: set ring param for running" > > + " interface %s failed. Please try to make the interface " > > + " down, then try again.\n", netdev->name); > > + ug_info->bdRingLenRx[queue] = rx_t; > > + ug_info->bdRingLenTx[queue] = tx_t; > > + } > [...] > > Bringing the interface down will call ucc_geth_close(), which will try > to free resources that have not been allocated! Sorry, I did not understand you on this point. There is no ucc_geth_close when 'open fail'. What you mean here exactly? > > If you cannot roll back a failed change then at least use dev_close() > and dev_open() rather than calling ucc_geth_{close,open}() directly, so > that the interface state is updated correctly. Or just refuse to make > the change if the interface is up. That make things more simply but I do not think that is necessary. Since there is no such restriction exist in most NIC drivers. :) Actually I did not see the 'fail of reopen' case. So I assume you may witnessed similar 'open fail' case in some rare cases. May you please give more input on this then I can 'make re-open safer' here. Thanks, -Liang Li > > Ben. > > -- > Ben Hutchings, Senior Software Engineer, Solarflare Communications > Not speaking for my employer; that's the marketing department's job. > They asked us to note that Solarflare product names are trademarked. -- 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