[PATCH v6 0/1] Implements MMIO emulation for lvx/stvx instructions

Jose Ricardo Ziviani joserz at linux.vnet.ibm.com
Sun Feb 4 07:24:25 AEDT 2018


v6:
  - Applied Paul's code suggestion to fix endianess
  - Moved kvmppc_get_vsr_dword_offset() back to #ifdef CONFIG_VSX

v5:
  - Fixed the mask off of the effective address

v4:
  - Changed KVM_MMIO_REG_VMX to 0xc0 because there are 64 VSX registers

v3:
  - Added Reported-by in the commit message

v2:
  - kvmppc_get_vsr_word_offset() moved back to its original place
  - EA AND ~0xF, following ISA.
  - fixed BE/LE cases

TESTS:

For testing purposes I wrote a small program that performs stvx/lvx using the
program's virtual memory and using MMIO. Load/Store into virtual memory is the
model I use to check if MMIO results are correct (because only MMIO is emulated
by KVM).

Results:

HOST LE - GUEST BE
address: 0x10034850010
0x21436587bbbbaaaa4444555578563412
io_address: 0x3fff89a20000
0x21436587bbbbaaaa4444555578563412

HOST LE - GUEST LE
address: 0x10033a20010
0x1234567855554444aaaabbbb87654321
io_address: 0x3fffb5380000
0x1234567855554444aaaabbbb87654321

HOST BE - GUEST BE
address: 0x1002c4a0010
0x21436587bbbbaaaa4444555578563412
io_address: 0x3ffface40000
0x21436587bbbbaaaa4444555578563412

HOST BR - GUEST LE
address: 0x100225e0010
0x1234567855554444aaaabbbb87654321
io_address: 0x3fff7fcb0000
0x1234567855554444aaaabbbb87654321

This patch implements MMIO emulation for two instructions: lvx and stvx.

Jose Ricardo Ziviani (1):
  KVM: PPC: Book3S: Add MMIO emulation for VMX instructions

 arch/powerpc/include/asm/kvm_host.h   |   2 +
 arch/powerpc/include/asm/kvm_ppc.h    |   4 +
 arch/powerpc/include/asm/ppc-opcode.h |   6 ++
 arch/powerpc/kvm/emulate_loadstore.c  |  34 ++++++++
 arch/powerpc/kvm/powerpc.c            | 150 ++++++++++++++++++++++++++++++++++
 5 files changed, 196 insertions(+)

-- 
2.14.3



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