@@ -1525,18 +1525,18 @@ int kvmppc_get_hypercall(CPUPPCState *env, uint8_t *buf, int buf_len)
}
/*
- * Fallback to always fail hypercalls:
+ * Fallback to always fail hypercalls regardless of endianness:
*
+ * tdi 0,r0,72 (becomes b .+8 in wrong endian, nop in good endian)
* li r3, -1
- * nop
- * nop
- * nop
+ * b .+8 (becomes nop in wrong endian)
+ * bswap32(li r3, -1)
*/
- hc[0] = 0x3860ffff;
- hc[1] = 0x60000000;
- hc[2] = 0x60000000;
- hc[3] = 0x60000000;
+ hc[0] = cpu_to_be32(0x08000048);
+ hc[1] = cpu_to_be32(0x3860ffff);
+ hc[2] = cpu_to_be32(0x48000008);
+ hc[3] = cpu_to_be32(bswap32(0x3860ffff));
return 0;
}
There were a few revisions of the Linux kernel that incorrectly swapped the hcall instructions when they saw ePAPR compliant hypercalls. We already have fixups for those in place when running with PR KVM, but HV KVM and systems that don't implement hypercalls at all are still broken because they fall back to the QEMU implementation of fallback hypercalls. So let's make the fallback hypercall instruction path endian agnostic. This only really works well for 64bit guests, but I don't think there are any 32bit systems left that don't implement real pv hcall support, so we'll never get into this code path. Signed-off-by: Alexander Graf <agraf@suse.de> --- target-ppc/kvm.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-)