Re: [Crash-utility] GCORE: add directly show backtrace function in crash

Hi Daisuke, On Tue, Oct 23, 2012 at 2:17 PM, HATAYAMA Daisuke <d.hatayama(a)jp.fujitsu.com > From: Lei Wen <adrian.wenl(a)gmail.com&gt; > Subject: Re: GCORE: add directly show backtrace function in crash > Date: Mon, 22 Oct 2012 15:36:47 +0800 > > > Hi Daisuke, > > > > On Mon, Oct 22, 2012 at 3:29 PM, HATAYAMA Daisuke < > d.hatayama(a)jp.fujitsu.com > >> > > >> From: Lei Wen <adrian.wenl(a)gmail.com&gt; > >> Subject: GCORE: add directly show backtrace function in crash > >> Date: Mon, 22 Oct 2012 12:21:49 +0800 > >> > >> > Hi Daisuke, > >> > > >> > I create a new option "-tT" for gcore, so that it could display bt for > >> user > >> > space > >> > directly inside crash itself, without needing to dump a separated core > >> file > >> > image, > >> > and analyze it in a different gdb env. > >> > > >> > The attached patch is directly based on below patch, and verify over > ARM > >> > platform. > >> > http://osdir.com/ml/general/2012-10/msg32677.html > >> > > >> > Before use the corresponding gcore command, we need set env in crash > by: > >> > > >> > crash>> gdb set solib-search-path [system lib path] > >> > > >> > crash>> gdb file [user space program symbol file] > >> > > >> > crash>> gcore -t [user space thread id] > >> > > >> > Thanks, > >> > Lei > >> > >> Hello Lei, > >> > >> That must be a useful feature, but I think it's very othogonal to > >> gcore command... > >> > >> Why not releasing your own extension module separately to gcore? > >> > > > > I put this function in gcore, is for gcore already provide the function > to > > get > > the general register for user space thread. If add another module, that > > part of function seems a little duplicated... > > > > I now understand why you want to add it in gcore. > > > Also provide the gcore the capability to either dump into a core file > > or directly display, user may have more choice over this. :) > > > > But, users then need to do more work such as loading application's > symbol files. There seems not so big difference. > > gdb has one symbol space only. If you load applications's symbols, it > can override kernel symbols. Then, gcore might behave abnormally. Can > users reset the loading of applications' symbols in any feature of > gdb? > Good question! However I am not a gdb expert... Hope someone here could give a solution... Also a silly question, since kernel runs well with user symbol, why gdb could not live with the chaos? No idea really... Thanks, Lei