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From: Felipe Balbi on 4 Aug 2010 07:20 Hi Uwe, I see that your commit 0db252452378aa7a9e001a13226e1cd1dc61453d removed the *_driver from the symbol whitelist when referencing init section (heh, it took a while), but could you explain what's the rationale behind that ? Thanks a lot -- balbi DefectiveByDesign.org -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: Uwe Kleine-König on 4 Aug 2010 08:30 Hi Felipe, On Wed, Aug 04, 2010 at 02:11:56PM +0300, Felipe Balbi wrote: > I see that your commit 0db252452378aa7a9e001a13226e1cd1dc61453d removed > the *_driver from the symbol whitelist when referencing init section > (heh, it took a while), but could you explain what's the rationale > behind that ? The rational is that it's AFAIK wrong if a driver references a function that lives in .init.text. Do you think that's wrong? Best regards Uwe -- Pengutronix e.K. | Uwe Kleine-K�nig | Industrial Linux Solutions | http://www.pengutronix.de/ | -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: Felipe Balbi on 9 Aug 2010 02:10 On Wed, Aug 04, 2010 at 02:26:59PM +0200, ext Uwe Kleine-K�nig wrote: >Hi Felipe, > >On Wed, Aug 04, 2010 at 02:11:56PM +0300, Felipe Balbi wrote: >> I see that your commit 0db252452378aa7a9e001a13226e1cd1dc61453d removed >> the *_driver from the symbol whitelist when referencing init section >> (heh, it took a while), but could you explain what's the rationale >> behind that ? >The rational is that it's AFAIK wrong if a driver references a function >that lives in .init.text. how about all the driver structures ? should they remove __init from probe() or stop saving the probe() function's pointer ? That can be done for e.g. platform drivers, but for cpufreq_driver structures, I can't see a way to avoid a section mismatch (not without changing the cpufreq code a bit, at least). And, to me, that init has to live in the .init.text section as it's pretty much only called to initialize the frequency table for the cpu. >Do you think that's wrong? no, no. Not saying that. Just wondering what will happen with several drivers, will they change from _driver to _ops or try to stop saving probe() pointers into the driver structure. -- balbi DefectiveByDesign.org -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: Uwe Kleine-König on 9 Aug 2010 02:50 Hello Felipe, On Mon, Aug 09, 2010 at 09:08:31AM +0300, Felipe Balbi wrote: > On Wed, Aug 04, 2010 at 02:26:59PM +0200, ext Uwe Kleine-K�nig wrote: >> Hi Felipe, >> >> On Wed, Aug 04, 2010 at 02:11:56PM +0300, Felipe Balbi wrote: >>> I see that your commit 0db252452378aa7a9e001a13226e1cd1dc61453d removed >>> the *_driver from the symbol whitelist when referencing init section >>> (heh, it took a while), but could you explain what's the rationale >>> behind that ? >> The rational is that it's AFAIK wrong if a driver references a function >> that lives in .init.text. > > how about all the driver structures ? should they remove __init from > probe() or stop saving the probe() function's pointer ? > > That can be done for e.g. platform drivers, but for cpufreq_driver > structures, I can't see a way to avoid a section mismatch (not without > changing the cpufreq code a bit, at least). And, to me, that init has to > live in the .init.text section as it's pretty much only called to > initialize the frequency table for the cpu. I think they need handling similar handling like the usb gadget drivers. See http://thread.gmane.org/gmane.linux.ports.ppc.embedded/37291/focus=34468 for the changes I suggested there. Best regards Uwe -- Pengutronix e.K. | Uwe Kleine-K�nig | Industrial Linux Solutions | http://www.pengutronix.de/ | -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: Felipe Balbi on 9 Aug 2010 06:40
Hi, On Mon, Aug 09, 2010 at 08:49:36AM +0200, ext Uwe Kleine-K�nig wrote: > http://thread.gmane.org/gmane.linux.ports.ppc.embedded/37291/focus=34468 > >for the changes I suggested there. I see, will look into it. Thanks -- balbi DefectiveByDesign.org -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/ |