[PATCH 4.19 10/85] xtensa: add missing isync to the cpu_reset TLB code

Greg Kroah-Hartman
2019-08-22T17:26:40Z

From: Max Filippov <jcmvbkbc@gmail.com>

commit cd8869f4cb257f22b89495ca40f5281e58ba359c upstream.

ITLB entry modifications must be followed by the isync instruction
before the new entries are possibly used. cpu_reset lacks one isync
between ITLB way 6 initialization and jump to the identity mapping.
Add missing isync to xtensa cpu_reset.

Cc: stable@vger.kernel.org
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
arch/xtensa/kernel/setup.c | 1 +
1 file changed, 1 insertion(+)

--- a/arch/xtensa/kernel/setup.c
+++ b/arch/xtensa/kernel/setup.c
@@ -515,6 +515,7 @@ void cpu_reset(void)
"add %2, %2, %7\n\t"
"addi %0, %0, -1\n\t"
"bnez %0, 1b\n\t"
+ "isync\n\t"
/* Jump to identity mapping */
"jx %3\n"
"2:\n\t"