On Wed, Jan 15, 2014 at 04:32:03PM -0800, Laura Abbott wrote: > Neither x86 nor arm64 get rid of existing mapping in paging_init. Is > there a reason this needs to be here for arm? Are there concerns about > alias mappings?
The early mappings we setup in the assembly code are imperfect - they're an approximation. We map just about enough memory to get the kernel going, and we setup a mapping for the debug stuff using a section mapping, which may not be appropriate. The permissions too are a just chosen to get things going, and the subsequent replacement of the page table entries is to fix all that up. We really don't want any old entries left behind. -- FTTC broadband for 0.8mile line: 5.8Mbps down 500kbps up. Estimation in database were 13.1 to 19Mbit for a good line, about 7.5+ for a bad. Estimate before purchase was "up to 13.2Mbit". -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
