I found a bug in resume() in 2.6 kernel. $f0 register may not be
saved on context switch in 64bit kernel. Here is a quick fix.
Or moving "sdc1 $f0" to fpu_save_16even might be better fix.
diff -u linux-mips/arch/mips/kernel/r4k_switch.S linux/arch/mips/kernel/r4k_switch.S
--- linux-mips/arch/mips/kernel/r4k_switch.S 1 Sep 2004 08:03:31 -0000 1.11
+++ linux/arch/mips/kernel/r4k_switch.S 7 Oct 2004 03:27:56 -0000
@@ -81,10 +81,10 @@
#ifdef CONFIG_MIPS64
sll t2, t0, 5
bgez t2, 2f
- sdc1 $f0, (THREAD_FPU + 0x00)(a0)
fpu_save_16odd a0
2:
fpu_save_16even a0 t1 # clobbers t1
+ sdc1 $f0, (THREAD_FPU + 0x00)(a0)
#endif
1:
---
Atsushi Nemoto
