[OpenBIOS] [PATCH v3] sparc32: fix __context corruption in __switch_context_nosave

[Artyom Tarasenko]

__switch_context_nosave shall not write to __context, only read it.

Signed-off-by: Artyom Tarasenko <atar4qemu at gmail.com>
--- arch/sparc32/switch.S       (revision 1024)
+++ arch/sparc32/switch.S       (working copy)
@@ -79,11 +79,15 @@
        set     (PSR_PS | PSR_S | PSR_PIL | PSR_EF), %g2
        wr      %g2, 0x0, %psr
 #endif
-
+        set     __context, %g1
+        /* Swap ctx pointer with %fp and jump*/
+        ba     __set_context
+         swap      [%g1], %fp
 __switch_context_nosave:
-       set     __context, %g1
-        /* Swap ctx pointer with %fp */
-        swap      [%g1], %fp
+        set     __context, %g1
+        /* load %fp from ctx pointer */
+        ld      [%g1], %fp
+__set_context:
        /* Load all registers */
         /* offset 0: %g0, no need to load */
         ld      [%fp + 4], %g1

---
Regards,
Artyom Tarasenko

solaris/sparc under qemu blog: http://tyom.blogspot.com/