On Feb 6, 2013, at 8:20 AM, Gleb Natapov wrote:
> On Wed, Nov 21, 2012 at 06:34:09PM -0800, Sanjay Lal wrote:
>> +static gpa_t kvm_trap_emul_gva_to_gpa_cb(gva_t gva)
>> +{
>> + gpa_t gpa;
>> + uint32_t kseg = KSEGX(gva);
>> +
>> + if ((kseg == CKSEG0) || (kseg == CKSEG1))
> You seems to be using KVM_GUEST_KSEGX variants on gva in all other
> places. Why not here?
This function is invoked to handle 2 scenarios:
(1) Parse the boot code config tables setup by QEMU's Malta emulation. The pointers in the tables are actual KSEG0 addresses (unmapped, cached) and not Guest KSEG0 addresses.
(2) Handle I/O accesses by the guest. On MIPS platforms, I/O device registers are mapped into the KSEG1 address space (unmapped, uncached). Again like (1) these are actual KSEG1 addresses, which cause an exception and are passed onto QEMU for I/O emulation.
Regards
Sanjay
