Messages in this thread | | | Date | Fri, 15 Oct 2010 17:25:07 +0300 | Subject | Re: [PATCH .36-rc8] arm: mm: allow, but warn, when issuing ioremap() on RAM | From | Felipe Contreras <> |
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On Fri, Oct 15, 2010 at 5:15 PM, Felipe Contreras <felipe.contreras@gmail.com> wrote: > From: Catalin Marinas <catalin.marinas@arm.com> > > Drivers have been relying on this behavior, but done so wrongly. > However, rather than breaking drivers from .35 to .36, we should warn on > .36 and only break on .37. This way we give a chance for contributors to > fix the issues. > > According to ARM, the behavior of having multiple mappings is > unspecified from ARMv6+. This causes real issues specially on modern > hardware, and specially with speculative prefetching. So drivers need to > be fixed. > > Also, since current hardware has palliative meassures to deal with > multiple mappings with the same memory type but diferent cacheability > attributes, ensure that such restriction is taking place.
Ah, disregard this, a similar one is on .36-rc8 already (06c1088), I wasn't CC'ed.
-- Felipe Contreras
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