Re: [PATCH] arm: Use kernel mm when updating section permissions

From: Russell King - ARM Linux
Date: Fri Nov 06 2015 - 15:47:05 EST


On Fri, Nov 06, 2015 at 10:44:32AM -0800, Laura Abbott wrote:
> with my test patch. I think setting both current->active_mm and &init_mm
> is sufficient. Maybe explicitly setting swapper_pg_dir would be cleaner?

Please, stop thinking like this. If you're trying to change the kernel
section mappings after threads have been spawned, you need to change
them for _all_ threads, which means you need to change them for every
page table that's in existence at that time - you can't do just one
table and hope everyone updates, it doesn't work like that.

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