diff options
Diffstat (limited to 'xen/arch/x86/hvm/emulate.c')
| -rw-r--r-- | xen/arch/x86/hvm/emulate.c | 26 |
1 files changed, 21 insertions, 5 deletions
diff --git a/xen/arch/x86/hvm/emulate.c b/xen/arch/x86/hvm/emulate.c index b2069971e1..15b2257c87 100644 --- a/xen/arch/x86/hvm/emulate.c +++ b/xen/arch/x86/hvm/emulate.c @@ -173,6 +173,13 @@ static int hvmemul_do_io( (p_data == NULL) ? HVMIO_dispatched : HVMIO_awaiting_completion; vio->io_size = size; + /* + * When retrying a repeated string instruction, force exit to guest after + * completion of the retried iteration to allow handling of interrupts. + */ + if ( vio->mmio_retrying ) + *reps = 1; + p->dir = dir; p->data_is_ptr = value_is_ptr; p->type = is_mmio ? IOREQ_TYPE_COPY : IOREQ_TYPE_PIO; @@ -202,8 +209,14 @@ static int hvmemul_do_io( case X86EMUL_RETRY: *reps = p->count; p->state = STATE_IORESP_READY; - hvm_io_assist(); - vio->io_state = HVMIO_none; + if ( !vio->mmio_retry ) + { + hvm_io_assist(); + vio->io_state = HVMIO_none; + } + else + /* Defer hvm_io_assist() invocation to hvm_do_resume(). */ + vio->io_state = HVMIO_handle_mmio_awaiting_completion; break; case X86EMUL_UNHANDLEABLE: rc = X86EMUL_RETRY; @@ -249,10 +262,9 @@ static int hvmemul_do_io( if ( bytes == 0 ) pa = vio->mmio_large_read_pa = addr; if ( (addr == (pa + bytes)) && - ((bytes + size) < - sizeof(vio->mmio_large_read)) ) + ((bytes + size) <= sizeof(vio->mmio_large_read)) ) { - memcpy(&vio->mmio_large_read[addr - pa], p_data, size); + memcpy(&vio->mmio_large_read[bytes], p_data, size); vio->mmio_large_read_bytes += size; } } @@ -1151,9 +1163,13 @@ int hvm_emulate_one( ? sizeof(hvmemul_ctxt->insn_buf) : 0; hvmemul_ctxt->exn_pending = 0; + vio->mmio_retrying = vio->mmio_retry; + vio->mmio_retry = 0; rc = x86_emulate(&hvmemul_ctxt->ctxt, &hvm_emulate_ops); + if ( rc == X86EMUL_OKAY && vio->mmio_retry ) + rc = X86EMUL_RETRY; if ( rc != X86EMUL_RETRY ) vio->mmio_large_read_bytes = vio->mmio_large_write_bytes = 0; |