From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sergei Shtylyov Subject: Re: [Kgdb-bugreport] [PATCH 2.6.20-rc7] 8139too KGDBoE fix Date: Thu, 01 Mar 2007 19:22:06 +0300 Message-ID: <45E6FDAE.2040009@ru.mvista.com> References: <1172746367.2515.31.camel@xenon> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Cc: kgdb-bugreport@lists.sourceforge.net, netdev@vger.kernel.org, Mark Huth To: komal Return-path: Received: from h155.mvista.com ([63.81.120.155]:27237 "EHLO imap.sh.mvista.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S965330AbXCAQWQ (ORCPT ); Thu, 1 Mar 2007 11:22:16 -0500 In-Reply-To: <1172746367.2515.31.camel@xenon> Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org komal wrote: > Hi all, > As the discussion was going on about the effects of trapping the > netpoll queue during KGDBoE debugging, I tried avoiding it. So in > eth_pre_exception_handler() I did not set net_poll_trap to 1 and did not > reset it back to 0 in eth_post_exception_handler() > file drivers/net/kgdboe.c > static void eth_pre_exception_handler(void) > { > /* Increment the module count when the debugger is active */ > if (!kgdb_connected) > try_module_get(THIS_MODULE); > // netpoll_set_trap(1); > } > > static void eth_post_exception_handler(void) > { > /* decrement the module count when the debugger detaches */ > if (!kgdb_connected) > module_put(THIS_MODULE); > // netpoll_set_trap(0); > } I'm afraid that was a wrong thing to do. We were talking only about disabling CONFIG_NETPOLL_TRAP option BTW, I don't see how CONFIG_NETPOLL_RX actually could influence anything -- looks like it just may be completely removed). > As i started testing KGDBoe, 1st time I did > (gdb)info threads > and it worked, but after that I set breakpoint > (gdb)break link_path_walk > after this any of the commands were not working and the test machine > went in hang state. > To provide more information, I am working on an i386/x86_64 Athlon box, > using 2.6.17 kernel and 100Mbps, full-duplex, VIA Rhine network card. This driver also seems prone to TX queue overwrites since its TX ring size is only 16. > -Regards > Komal Nawandar WBR, Sergei