powerpc/kexec: Reset secondary cpu endianness before kexec

If the target kernel does not inlcude the FIXUP_ENDIAN check, coming
from a different-endian kernel will cause the target kernel to panic.
All ppc64 kernels can handle starting in big-endian mode, so return to
big-endian before branching into the target kernel.

This mainly affects pseries as secondaries on powernv are returned to
OPAL.

Signed-off-by: Samuel Mendoza-Jonas <sam.mj@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

diff --git a/arch/powerpc/kernel/misc_64.S b/arch/powerpc/kernel/misc_64.S
index 4e314b9..6e4168c 100644 (file)
--- a/arch/powerpc/kernel/misc_64.S
+++ b/arch/powerpc/kernel/misc_64.S
@@ -475,9 +475,18 @@ _GLOBAL(kexec_wait)
 #ifdef CONFIG_KEXEC            /* use no memory without kexec */
        lwz     r4,0(r5)
        cmpwi   0,r4,0
-       bnea    0x60
+       beq     99b
+#ifdef CONFIG_PPC_BOOK3S_64
+       li      r10,0x60
+       mfmsr   r11
+       clrrdi  r11,r11,1       /* Clear MSR_LE */
+       mtsrr0  r10
+       mtsrr1  r11
+       rfid
+#else
+       ba      0x60
+#endif
 #endif
-       b       99b
 
 /* this can be in text because we won't change it until we are
  * running in real anyways