Hi, I've been tracking down why scsi generic devices (using SG_IO)
don't work any more. After adding debug, I can see that it actually
submits the scsi CDB in hw/scsi-generic.c/execute_command(), but that
the hw/scsi-generic.c/scsi_read_complete() callback is never called.
This is because these are done with ioctls, and the posix async ioctl
code is, I think, broken right now. Some more debugging, led me to
posix-aio-compat.c/posix_aio_process_queue():
if (acb->async_context_id != async_context_id) {
The async_context_ids don't match, so the request is never handled.
This is because the acb->async_context_id field is not initialised in
posix-aio-compat.c/paio_ioctl() (compare with
posix-aio-compat.c/paio_submit()). The attached patch adds the missing
line in.
This seems to fix the problem. Of course, /now/ I'm getting other
weird problems (as I'm trying to see if I can get slysoft anydvd
working in a KVM winXP vm), but they need further investigation and
likely other fixes.
Please forgive me if I'm mistaken in this, I've only just started
looking at the qemu code.
diff -Naur qemu-kvm-0.12.5.orig//posix-aio-compat.c qemu-kvm-0.12.5/posix-aio-compat.c
--- qemu-kvm-0.12.5.orig//posix-aio-compat.c 2010-07-27 01:43:53.000000000 +0100
+++ qemu-kvm-0.12.5/posix-aio-compat.c 2010-08-07 01:49:07.051265778 +0100
@@ -597,6 +597,7 @@
acb->aio_type = QEMU_AIO_IOCTL;
acb->aio_fildes = fd;
acb->ev_signo = SIGUSR2;
+ acb->async_context_id = get_async_context_id();
acb->aio_offset = 0;
acb->aio_ioctl_buf = buf;
acb->aio_ioctl_cmd = req;
