remap_pfn_range() + outer_flush_range()

From: Wohlmuth, Oliver
Date: Wed Aug 02 2017 - 12:03:12 EST


Hi,

I'm implementing a 2D graphics driver for an ARM A9 multicore SoC. As part of this, I'm using remap_pfn_range()
to map memory to user space. During testing I realized that remap_pfn_range() flushes the L1 cache, but doesn't
flush the L2 cache. As a result, I can get L2 cache hits even if I mapped the memory uncached.

What is the motivation for this?

Any help on this is greatly appreciated.

Best regards,
Oliver

P.S. I'm sorry if this is a bit of topic for this mailing list, but I didn't know where else to post this.