USB mass storage and ARM cache coherency

[Oliver Neukum]

Am Freitag, 19. Februar 2010 18:36:51 schrieb Catalin Marinas:
> If a page is already mapped in user space, flush_dcache_page() on ARM
> does the flushing rather than deferring it to update_mmu_cache(). The
> PIO HCD drivers, however, don't call flush_dcache_page(). Is it possible
> that the HCD could transfer data into a page cache page already mapped
> in user space? My understanding is that the scenario above is possible.

Yes, video drivers do that.

	Regards
		Oliver