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/kernel/entry.S b/arch/xtensa/kernel/entry.S
index fa94512..9298742 100644
--- a/arch/xtensa/kernel/entry.S
+++ b/arch/xtensa/kernel/entry.S
@@ -458,7 +458,7 @@
_bbsi.l a4, TIF_NEED_RESCHED, 3f
_bbsi.l a4, TIF_NOTIFY_RESUME, 2f
- _bbci.l a4, TIF_SIGPENDING, 4f
+ _bbci.l a4, TIF_SIGPENDING, 5f
2: l32i a4, a1, PT_DEPC
bgeui a4, VALID_DOUBLE_EXCEPTION_ADDRESS, 4f
@@ -476,6 +476,13 @@
callx4 a4
j 1b
+5:
+#ifdef CONFIG_DEBUG_TLB_SANITY
+ l32i a4, a1, PT_DEPC
+ bgeui a4, VALID_DOUBLE_EXCEPTION_ADDRESS, 4f
+ movi a4, check_tlb_sanity
+ callx4 a4
+#endif
4: /* Restore optional registers. */
load_xtregs_opt a1 a2 a4 a5 a6 a7 PT_XTREGS_OPT