xtensa: userspace: Fixes in xtensa_userspace_enter
- spill windows in the current context (before switching task) since
it will be erased.
- Remove unnucessary load/mov
Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
diff --git a/arch/xtensa/core/userspace.S b/arch/xtensa/core/userspace.S
index 42fe86f..1578e3b 100644
--- a/arch/xtensa/core/userspace.S
+++ b/arch/xtensa/core/userspace.S
@@ -276,13 +276,12 @@
*/
entry a1, 16
+ SPILL_ALL_WINDOWS
+
/* We have to switch to kernel stack before spill kernel data and
* erase user stack to avoid leak from previous context.
*/
mov a1, a7 /* stack start (low address) */
- addi a1, a1, -16
-
- SPILL_ALL_WINDOWS
rsr a0, ZSR_CPU
l32i a0, a0, ___cpu_t_current_OFFSET
@@ -329,11 +328,8 @@
l32i a8, a1, 12
l32i a9, a1, 8
- /* stash user stack */
- l32i a0, a1, 4
-
/* Go back to user stack */
- mov a1, a0
+ l32i a1, a1, 4
movi a0, z_thread_entry
wsr.epc2 a0
@@ -352,6 +348,7 @@
wsr a0, EPS2
+ /* Wipe out a0 (thre is no return from this function */
movi a0, 0
rfi 2
