tools/libxenstat: don't lose all VIFs when dom0 has no Linux bridge

[PATCH] tools/libxenstat: don't lose all VIFs when dom0 has no Linux bridge

Posted by Olivier Lambert 2 weeks, 6 days ago

xenstat_collect_networks() looks for a Linux bridge (a
/sys/class/net/*/bridge directory) so that, with bonding, dom0 can be
given the bridge's counters. When there is none, as on hosts using Open
vSwitch (the XCP-ng default), routed networking or only libvirt's
virbr0 (which is excluded on purpose), getBridge() leaves devBridge
empty. strstr(iface, "") then matches every interface, and devNoBridge
is just "p", so every VIF with a standard name (vifN.M, vifN.M-emu)
takes the bridge branch instead of being attached to its domain. Every
domain ends up with zero networks, and xentop shows NETS 0.

Only take the bridge branch when a bridge was actually found.

Fixes: 1fd93d4f8cb8 ("xenstat: Linux dom0 statistics for case we use network bonding")
Assisted-by: Claude-Code:claude-opus-5-5
Signed-off-by: Olivier Lambert <olivier.lambert@vates.tech>
---
 tools/libs/stat/xenstat_linux.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/tools/libs/stat/xenstat_linux.c b/tools/libs/stat/xenstat_linux.c
index b60e3fdcab..2a7d2f1a96 100644
--- a/tools/libs/stat/xenstat_linux.c
+++ b/tools/libs/stat/xenstat_linux.c
@@ -322,7 +322,8 @@ int xenstat_collect_networks(xenstat_node * node)
 
 		/* If the device parsed is network bridge and both tx & rx packets are zero, we are most */
 		/* likely using bonding so we alter the configuration for dom0 to have bridge stats */
-		if ((strstr(iface, devBridge) != NULL) &&
+		if ((devBridge[0] != '\0') &&
+		    (strstr(iface, devBridge) != NULL) &&
 		    (strstr(iface, devNoBridge) == NULL) &&
 		    ((domain = xenstat_node_domain(node, 0)) != NULL)) {
 			for (i = 0; i < domain->num_networks; i++) {
-- 
2.53.0



-- 
Olivier Lambert | Vates CEO

XCP-ng & Xen Orchestra - Vates solutions
Book a meeting with me: https://calrs.vates.tech/u/olivier-lambert
web: https://vates.tech

Re: [PATCH] tools/libxenstat: don't lose all VIFs when dom0 has no Linux bridge

Posted by Jason Andryuk 2 weeks, 3 days ago

On 2026-10-03 03:17, Olivier Lambert wrote:
> xenstat_collect_networks() looks for a Linux bridge (a
> /sys/class/net/*/bridge directory) so that, with bonding, dom0 can be
> given the bridge's counters. When there is none, as on hosts using Open
> vSwitch (the XCP-ng default), routed networking or only libvirt's
> virbr0 (which is excluded on purpose), getBridge() leaves devBridge
> empty. strstr(iface, "") then matches every interface, and devNoBridge
> is just "p", so every VIF with a standard name (vifN.M, vifN.M-emu)
> takes the bridge branch instead of being attached to its domain. Every
> domain ends up with zero networks, and xentop shows NETS 0.
> 
> Only take the bridge branch when a bridge was actually found.
> 
> Fixes: 1fd93d4f8cb8 ("xenstat: Linux dom0 statistics for case we use network bonding")
> Assisted-by: Claude-Code:claude-opus-5-5
> Signed-off-by: Olivier Lambert <olivier.lambert@vates.tech>

Tested-by: Jason Andryuk <jason.andryuk@amd.com>
Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>

> ---
>   tools/libs/stat/xenstat_linux.c | 3 ++-
>   1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/tools/libs/stat/xenstat_linux.c b/tools/libs/stat/xenstat_linux.c
> index b60e3fdcab..2a7d2f1a96 100644
> --- a/tools/libs/stat/xenstat_linux.c
> +++ b/tools/libs/stat/xenstat_linux.c
> @@ -322,7 +322,8 @@ int xenstat_collect_networks(xenstat_node * node)
>   
>   		/* If the device parsed is network bridge and both tx & rx packets are zero, we are most */
>   		/* likely using bonding so we alter the configuration for dom0 to have bridge stats */
> -		if ((strstr(iface, devBridge) != NULL) &&
> +		if ((devBridge[0] != '\0') &&
> +		    (strstr(iface, devBridge) != NULL) &&
>   		    (strstr(iface, devNoBridge) == NULL) &&
>   		    ((domain = xenstat_node_domain(node, 0)) != NULL)) {
>   			for (i = 0; i < domain->num_networks; i++) {

Re: [PATCH] tools/libxenstat: don't lose all VIFs when dom0 has no Linux bridge

Posted by Anthony PERARD 1 week, 4 days ago

On Mon, Oct 05, 2026 at 04:49:43PM -0400, Jason Andryuk wrote:
> On 2026-10-03 03:17, Olivier Lambert wrote:
> > xenstat_collect_networks() looks for a Linux bridge (a
> > /sys/class/net/*/bridge directory) so that, with bonding, dom0 can be
> > given the bridge's counters. When there is none, as on hosts using Open
> > vSwitch (the XCP-ng default), routed networking or only libvirt's
> > virbr0 (which is excluded on purpose), getBridge() leaves devBridge
> > empty. strstr(iface, "") then matches every interface, and devNoBridge
> > is just "p", so every VIF with a standard name (vifN.M, vifN.M-emu)
> > takes the bridge branch instead of being attached to its domain. Every
> > domain ends up with zero networks, and xentop shows NETS 0.
> > 
> > Only take the bridge branch when a bridge was actually found.
> > 
> > Fixes: 1fd93d4f8cb8 ("xenstat: Linux dom0 statistics for case we use network bonding")
> > Assisted-by: Claude-Code:claude-opus-5-5
> > Signed-off-by: Olivier Lambert <olivier.lambert@vates.tech>
> 
> Tested-by: Jason Andryuk <jason.andryuk@amd.com>
> Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>

Acked-by: Anthony PERARD <anthony.perard@vates.tech>

Thanks,


-- 
Anthony Perard | Vates XCP-ng Developer

XCP-ng & Xen Orchestra - Vates solutions

web: https://vates.tech