xtensa: check TLB sanity on return to userspace
- check that user TLB mappings correspond to the current page table;
- check that TLB mapping VPN is in the kernel/user address range
in accordance with its ASID.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
diff --git a/arch/xtensa/Kconfig.debug b/arch/xtensa/Kconfig.debug
index a34010e..af7da74 100644
--- a/arch/xtensa/Kconfig.debug
+++ b/arch/xtensa/Kconfig.debug
@@ -2,6 +2,16 @@
source "lib/Kconfig.debug"
+config DEBUG_TLB_SANITY
+ bool "Debug TLB sanity"
+ depends on DEBUG_KERNEL
+ help
+ Enable this to turn on TLB sanity check on each entry to userspace.
+ This check can spot missing TLB invalidation/wrong PTE permissions/
+ premature page freeing.
+
+ If unsure, say N.
+
config LD_NO_RELAX
bool "Disable linker relaxation"
default n