On Tue, Dec 07, 2010 at 12:45:04AM -0200, Piter PUNK wrote:
> Matt Domsch wrote:
> >I see this in the udev debug logs when using biosdevname (which I
> >finally got working with SR-IOV devices tonight):
> >
> >renamed network interface eth60 to eth60-pci2#0_60
> >renamed network interface eth60-pci2#0_60 to pci2#0_60
> >
> >So, it worked, however, note that the rename happens in 2 steps, the
> >middle step of which uses a name that's dangerously close to
> >IFNAMSIZ, in fact it is 15 chars there.
> >
> ><...>
> >
> >I need a solution in which the intermediate name doesn't exceed 15
> >characters, and is guaranteed to be unique, as there may be lots of
> >udev instances running in parallel trying to do the same thing.
> >
> >Ideas?
>
> As we talk on #udev, there is a patch that uses hash32 function inside
> libudev to create
> the intermediate name. We use the "oldname-newname" to create the hash.
> With that,
> exceeding IFNAMSIZ isn't a problem:
Piter's patch works for me, and I need this in udev fairly quickly
please. Some kind folks from IBM have been testing biosdevname with
quad-port Intel SR-IOV-capable devices, and instantiating all the VFs,
can easily have >100 eth* devices created in the kernel
instantaneously. That bumps step 1 in the 2-step rename operation
over IFNAMSIZ (eth100-pci2#3_62 is 16 chars).
Please apply. I'm re-pasting from the original email for convenience.
Tested-by: Matt Domsch <Matt_Domsch@xxxxxxxx>
Thanks,
Matt
--
Matt Domsch
Technology Strategist
Dell | Office of the CTO
diff --git a/udev/udev-event.c b/udev/udev-event.c
index 0648735..5387c00 100644
--- a/udev/udev-event.c
+++ b/udev/udev-event.c
@@ -462,6 +462,7 @@ static void rename_netif_kernel_log(struct ifreq ifr)
static int rename_netif(struct udev_event *event)
{
struct udev_device *dev = event->dev;
+ char iftmp[IFNAMSIZ];
int sk;
struct ifreq ifr;
int loop;
@@ -492,7 +493,8 @@ static int rename_netif(struct udev_event *event)
goto out;
/* free our own name, another process may wait for us */
- util_strscpyl(ifr.ifr_newname, IFNAMSIZ, udev_device_get_sysname(dev), "-", event->name, NULL);
+ util_strscpyl(iftmp, IFNAMSIZ, udev_device_get_sysname(dev), "-", event->name, NULL);
+ sprintf(ifr.ifr_newname, "eth_%X",util_string_hash32(iftmp));
err = ioctl(sk, SIOCSIFNAME, &ifr);
if (err < 0) {
err = -errno;
--
To unsubscribe from this list: send the line "unsubscribe linux-hotplug" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
