Re: [kvm-devel] Using VMChannel to communicate with the host.

[Cameron M. <ca...@cs...>]

On 15-Sep-07, at 4:47 PM, Dor Laor wrote:

> Cam Macdonell wrote:
>> It didn't work.  I used the following option: -vmchannel
>> di:2258,tcp:0:4444,server (the // confused kvm) and when the VM =20
>> booted,
>> I connected with "telnet localhost 4444" which allowed the boot to
>> proceed.  But, I didn't get the hello host message when I loaded the
>> hypercall module.  dmesg did show that the module loaded =20
>> successfully.
>> I'll dig around with it and see what else I can figure ou
>>
> I just tried it and it worked. I used fc7 2.6.21 kernel, 64 bits  =20
> for the guest.
> Can you send the relevant dmesg?

Here is the dmesg output within the guest.  I am running KVM-39 on =20
Ubuntu 2.6.20 kernel, 32 bit for both
host and guest.

[  540.144000] Qumranet_hypercall_driver
[  540.148000] pci dev 0000:00:04.0 (id 5002:2258 rev 00) is a guest =20
hypercall device
[  540.148000] PCI: Found IRQ 9 for device 0000:00:04.0
[  540.148000] hypercall_init_board: PIO region size =3D=3D 0x100
[  540.148000] hypercall_init_board: MMIO region size =3D=3D 0x00
[  540.148000] name=3D: base_addr=3D0xc200, io_addr=3D0x1c200, IRQ=3D9

For what it's worth, I can compile the driver/hypercall.c file that =20
comes with kvm-39.  However, I can't compile your hypercall.c =20
implementation, I get the following error:

make -C /lib/modules/2.6.20-16-generic/build M=3D`pwd` "$@"
make[1]: Entering directory `/usr/src/linux-headers-2.6.20-16-generic'
   CC [M]  /home/kvm/kvm-userspace/drivers/hypercall.o
/home/kvm/kvm-userspace/drivers/hypercall.c: In function =20
=91hypercall_do_tasklet=92:
/home/kvm/kvm-userspace/drivers/hypercall.c:226: error: invalid =20
lvalue in unary =91&=92
/home/kvm/kvm-userspace/drivers/hypercall.c:226: error: invalid =20
lvalue in unary =91&=92
/home/kvm/kvm-userspace/drivers/hypercall.c:231: warning: implicit =20
declaration of function =91hypercall_tx=92
/home/kvm/kvm-userspace/drivers/hypercall.c: At top level:
/home/kvm/kvm-userspace/drivers/hypercall.c:236: error: static =20
declaration of =91hypercall_tx=92 follows non-static declaration
/home/kvm/kvm-userspace/drivers/hypercall.c:231: error: previous =20
implicit declaration of =91hypercall_tx=92 was here
/home/kvm/kvm-userspace/drivers/hypercall.c: In function =20
=91hypercall_interrupt=92:
/home/kvm/kvm-userspace/drivers/hypercall.c:302: warning: passing =20
argument 1 of =91__constant_memcpy=92 makes pointer from integer without =
=20
a cast
/home/kvm/kvm-userspace/drivers/hypercall.c:302: warning: passing =20
argument 1 of =91__memcpy=92 makes pointer from integer without a cast
/home/kvm/kvm-userspace/drivers/hypercall.c: In function =20
=91hypercall_open=92:
/home/kvm/kvm-userspace/drivers/hypercall.c:320: warning: passing =20
argument 2 of =91request_irq=92 from incompatible pointer type
/home/kvm/kvm-userspace/drivers/hypercall.c:326: warning: assignment =20
makes integer from pointer without a cast
/home/kvm/kvm-userspace/drivers/hypercall.c:328: error: =20
=91hypercall_task=92 undeclared (first use in this function)
/home/kvm/kvm-userspace/drivers/hypercall.c:328: error: (Each =20
undeclared identifier is reported only once
/home/kvm/kvm-userspace/drivers/hypercall.c:328: error: for each =20
function it appears in.)
make[2]: *** [/home/kvm/kvm-userspace/drivers/hypercall.o] Error 1
make[1]: *** [_module_/home/kvm/kvm-userspace/drivers] Error 2
make[1]: Leaving directory `/usr/src/linux-headers-2.6.20-16-generic'
make: *** [all] Error 2

Thanks,
Cam

-----------------------------------------------
A. Cameron Macdonell
Ph.D. Student
Department of Computing Science
University of Alberta
ca...@cs...