Messages in this thread | | | Date | Thu, 19 Oct 2006 21:03:24 -0700 | From | Greg KH <> | Subject | Re: pci_fixup_video change blows up on sparc64 |
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On Fri, Oct 20, 2006 at 12:21:24PM +0900, eiichiro.oiwa.nm@hitachi.com wrote: > From: Greg KH <greg@kroah.com> > >On Thu, Oct 19, 2006 at 03:32:28PM -0700, David Miller wrote: > >> From: <eiichiro.oiwa.nm@hitachi.com> > >> Date: Thu, 19 Oct 2006 19:49:26 +0900 > >> > >> > The "0xc0000" is a physical address. The BAR (PCI base address) is also > >> > a physcail address. There are no difference. > >> > >> Your assertion that the BAR is a physical address is very platform > >> specific. It may be a "physical address in PCI bus space", but > >> that has no relation to the first argument passed to ioremap() > >> which is defined in a completely different way. > >> > >> On many platforms, the BAR of PCI devices are translated into an > >> appropriate "ioremap() cookie" in the struct pci_dev resource[] array > >> entries, so that they can be used properly as the first argument to > >> ioremap(). Only address cookies properly setup by the platform may be > >> legally passed into ioremap() as the first argument. No such setups > >> are being made on this raw 0xc0000 address. > >> > >> So, as you can see, I/O port and I/O memory space work differently on > >> different platforms and this abstraction of the first argument to > >> ioremap() is how we provide support for such differences. > >> > >> If you try to access 0xc0000 via ioremap() on sparc64, it is going to > >> try and access that area non-cacheable which, since 0xc0000 is > >> physical RAM, will result in a BUS ERROR and a crash. > >> > >> This physical location might be the area for the video ROM on x86, > >> x86_64, and perhaps even IA64, but it certainly is not used this way > >> on sparc64 systems. > >> > >> I really would like to see this regression fixed, or at the very > >> least this code protected by X86, X86_64, IA64 conditionals. > > > >I agree. Eiichiro, care to send me an patch to fix this somehow? Or do > >you want me to just revert it? > > > >thanks, > > > >greg k-h > > > > Ok, I sent an patch to fix on only x86, x86_64 and IA64 for 2.6.18. > Do you need an patch aganist 2.6.19-git?
I can't apply a patch against an old kernel, especially when the problem is with the new release :)
Please make it against Linus's latest tree, which is where the problem is. Also, please address David's latest comments about the patch.
thanks,
greg k-h - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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