From mboxrd@z Thu Jan 1 00:00:00 1970 From: Blaisorblade Date: Fri, 16 Feb 2007 18:38:16 +0000 Subject: Kconfig bug (was: Re: fault-injection framework on ia64) Message-Id: <200702161938.17340.blaisorblade@yahoo.it> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-ia64@vger.kernel.org On Friday 16 February 2007 18:30, Akinobu Mita wrote: > > But if STACKTRACE depends on STACKTRACE_SUPPORT, which isn't defined on > > ia64, kconfig should disable FAULT_INJECTION altogether with my patch (as > > it did before it). I don't think that FAULT_INJECTION could be enabled > > before my patch, right? > > > > _BUT_ probably STACKTRACE_SUPPORT should be defined, with default n and > > no prompt, on ia64, or Kconfig gets confused (it should output a warning, > > like 'undefined symbol STACKTRACE_SUPPORT'). We on UML used to get > > warning when INPUT was used but not defined. Hmmm.... > > Really? I intentionaly removed the STACKTRACE_SUPPORT in x86_64 Kconfig, > then I did make menuconfig. But I didn't get such warning. Well, I got that warning, and I don't get it on STACKTRACE_SUPPORT. Strange. But it was time ago... However, more important, if I remove STACKTRACE_SUPPORT, or if I make it 'default n', FAULT_INJECTION can still be enabled, even if it selects STACKTRACE which has a failed dependency (tested on UML). Which is a Kconfig bug - if A selects B and B depends on C, no dependency of A on C is deduced. Right Roman? This Kconfig bug explains how your bug could surface. This also means that my patch cannot to go -stable because it would cause problems on IA64 and any arch without STACKTRACE_SUPPORT. See if yours can, Akinobu. -- Inform me of my mistakes, so I can add them to my list! Paolo Giarrusso, aka Blaisorblade http://www.user-mode-linux.org/~blaisorblade Chiacchiera con i tuoi amici in tempo reale! http://it.yahoo.com/mail_it/foot/*http://it.messenger.yahoo.com