Xen project Mailing List

On Tue, Feb 6, 2018 at 2:36 PM, Wei Liu <wei.liu2@xxxxxxxxxx> wrote:

On Thu, Dec 14, 2017 at 04:14:12PM +0200, Oleksandr Grytsov wrote:
> From: Oleksandr Grytsov <oleksandr_grytsov@xxxxxxxx>
>
> We have following arm-based setup:
>
> - Dom0 with xen and xen tools;
> - Dom1 with device backends (but it is not the driver domain);

What is your definition of a "driver domain"? What does it do in this
case?

I seem to have seen people use this term in different contexts to mean
slightly different things. I need to figure out what you actually mean
first.

I see in the libxl/xl sources that closing PV devices is done differently

in case backends are in Dom0 and are in other domain. It is called as

driver domain in the sources. So, I don't have clear understanding

what does it mean. In our setup backends are in Dom1 and xl is in Dom0.

And I see that xl dosn't close PV device on domain reboot or shutdown.

> - Dom2 with device frontend;
>
> On Dom2 destroying we have timeout error. Because xl treats our
> Dom1 as driver domain and waits for backend path to be cleared
> by the driver domain which is not our case.
>
> According to libxl__domain_make in case of driver domain it has
> "libxl" xen store entry:
>
> if (libxl_defbool_val(info->driver_domain)) {
> /*
> * Create a local "libxl" directory for each guest, since we might want
> * to use libxl from inside the guest
> */
> libxl__xs_mknod(gc, t, GCSPRINTF("%s/libxl", dom_path), rwperm,
> ARRAY_SIZE(rwperm));
>
> This patch introduces libxl__is_driver_domain which determines the driver
> domain by checking if "libxl" entry is present and uses this function on
> device destroy to check by whom domain path should be cleaned up (libxl
> or the driver domain).
>
> Oleksandr Grytsov (1):
> libxl: add libxl__is_driver_domain function
>
> tools/libxl/libxl_device.c | 17 ++++++++++-------
> tools/libxl/libxl_internal.c | 16 ++++++++++++++++
> tools/libxl/libxl_internal.h | 4 ++++
> 3 files changed, 30 insertions(+), 7 deletions(-)
>
> --
> 2.7.4
>

Best Regards,
Oleksandr Grytsov.

Re: [Xen-devel] [PATCH] libxl: add libxl__is_driver_domain function