| Message ID | 20240517032156.1490515-5-xin.wang2@amd.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | Guest XenStore page allocation for 11 Dom0less domUs | expand |
On Fri, 17 May 2024, Henry Wang wrote: > With the new allocation strategy of Dom0less DomUs XenStore page, > update the doc of the late XenStore init protocol accordingly. > > Signed-off-by: Henry Wang <xin.wang2@amd.com> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> > --- > v3: > - Wording change. > v2: > - New patch. > --- > docs/features/dom0less.pandoc | 12 +++++++----- > 1 file changed, 7 insertions(+), 5 deletions(-) > > diff --git a/docs/features/dom0less.pandoc b/docs/features/dom0less.pandoc > index 725afa0558..8b178edee0 100644 > --- a/docs/features/dom0less.pandoc > +++ b/docs/features/dom0less.pandoc > @@ -110,9 +110,10 @@ hotplug PV drivers to dom0less guests. E.g. xl network-attach domU. > The implementation works as follows: > - Xen allocates the xenstore event channel for each dom0less domU that > has the "xen,enhanced" property, and sets HVM_PARAM_STORE_EVTCHN > -- Xen does *not* allocate the xenstore page and sets HVM_PARAM_STORE_PFN > - to ~0ULL (invalid) > -- Dom0less domU kernels check that HVM_PARAM_STORE_PFN is set to invalid > +- Xen allocates the xenstore page and sets HVM_PARAM_STORE_PFN as well > + as the connection status to XENSTORE_RECONNECT. > +- Dom0less domU kernels check that HVM_PARAM_STORE_PFN is set to > + ~0ULL (invalid) or the connection status is *not* XENSTORE_CONNECTED. > - Old kernels will continue without xenstore support (Note: some old > buggy kernels might crash because they don't check the validity of > HVM_PARAM_STORE_PFN before using it! Disable "xen,enhanced" in > @@ -121,13 +122,14 @@ The implementation works as follows: > channel (HVM_PARAM_STORE_EVTCHN) before continuing with the > initialization > - Once dom0 is booted, init-dom0less is executed: > - - it allocates the xenstore shared page and sets HVM_PARAM_STORE_PFN > + - it gets the xenstore shared page from HVM_PARAM_STORE_PFN > - it calls xs_introduce_domain > - Xenstored notices the new domain, initializes interfaces as usual, and > sends an event channel notification to the domain using the xenstore > event channel (HVM_PARAM_STORE_EVTCHN) > - The Linux domU kernel receives the event channel notification, checks > - HVM_PARAM_STORE_PFN again and continue with the initialization > + HVM_PARAM_STORE_PFN and the connection status again and continue with > + the initialization > > > Limitations > -- > 2.34.1 > >
diff --git a/docs/features/dom0less.pandoc b/docs/features/dom0less.pandoc index 725afa0558..8b178edee0 100644 --- a/docs/features/dom0less.pandoc +++ b/docs/features/dom0less.pandoc @@ -110,9 +110,10 @@ hotplug PV drivers to dom0less guests. E.g. xl network-attach domU. The implementation works as follows: - Xen allocates the xenstore event channel for each dom0less domU that has the "xen,enhanced" property, and sets HVM_PARAM_STORE_EVTCHN -- Xen does *not* allocate the xenstore page and sets HVM_PARAM_STORE_PFN - to ~0ULL (invalid) -- Dom0less domU kernels check that HVM_PARAM_STORE_PFN is set to invalid +- Xen allocates the xenstore page and sets HVM_PARAM_STORE_PFN as well + as the connection status to XENSTORE_RECONNECT. +- Dom0less domU kernels check that HVM_PARAM_STORE_PFN is set to + ~0ULL (invalid) or the connection status is *not* XENSTORE_CONNECTED. - Old kernels will continue without xenstore support (Note: some old buggy kernels might crash because they don't check the validity of HVM_PARAM_STORE_PFN before using it! Disable "xen,enhanced" in @@ -121,13 +122,14 @@ The implementation works as follows: channel (HVM_PARAM_STORE_EVTCHN) before continuing with the initialization - Once dom0 is booted, init-dom0less is executed: - - it allocates the xenstore shared page and sets HVM_PARAM_STORE_PFN + - it gets the xenstore shared page from HVM_PARAM_STORE_PFN - it calls xs_introduce_domain - Xenstored notices the new domain, initializes interfaces as usual, and sends an event channel notification to the domain using the xenstore event channel (HVM_PARAM_STORE_EVTCHN) - The Linux domU kernel receives the event channel notification, checks - HVM_PARAM_STORE_PFN again and continue with the initialization + HVM_PARAM_STORE_PFN and the connection status again and continue with + the initialization Limitations
With the new allocation strategy of Dom0less DomUs XenStore page, update the doc of the late XenStore init protocol accordingly. Signed-off-by: Henry Wang <xin.wang2@amd.com> --- v3: - Wording change. v2: - New patch. --- docs/features/dom0less.pandoc | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-)