tree ca90a3abad7717fa27186c38c2ed0c02f93ab7de
parent 6e799cb69a70eedbb41561b750f7180c12cff280
author Thomas Gleixner <tglx@linutronix.de> 1605728920 +0100
committer Thomas Gleixner <tglx@linutronix.de> 1606225328 +0100

mm/highmem: Provide CONFIG_DEBUG_KMAP_LOCAL_FORCE_MAP

CONFIG_DEBUG_KMAP_LOCAL, which is selected by CONFIG_DEBUG_HIGHMEM is only
providing guard pages, but does not provide a mechanism to enforce the
usage of the kmap_local() infrastructure.

Provide CONFIG_DEBUG_KMAP_LOCAL_FORCE_MAP which forces the temporary
mapping even for lowmem pages. This needs to be a seperate config switch
because this only works on architectures which do not have cache aliasing
problems.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20201118204007.028261233@linutronix.de