Rather than listening to 'add' udev events, listen for 'bind' events instead. When we get an 'add' event, the sysfs tree for the device is often not ready yet. In that case we sleep in a loop until the sysfs tree appears, or give up after a timeout. udev added the 'bind' event to give userspace a signal that indicated when driver-specific attributes were available to be used. In other words, the sysfs tree *should* be ready and usable at this point. But just to be safe, we'll leave the wait loop in the code to handle corner cases, with the hope that it'll never be used. The udev 'bind' event was added in kernel 4.14 and the oldest platform we support has kernel 4.18, so it should be safe to make this change. Previous discussion on the mailing list: https://listman.redhat.com/archives/libvir-list/2022-August/233933.html Signed-off-by: Jonathon Jongsma <jjongsma@xxxxxxxxxx> --- src/node_device/node_device_udev.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/src/node_device/node_device_udev.c b/src/node_device/node_device_udev.c index 07c10f0d88..781a8b32a6 100644 --- a/src/node_device/node_device_udev.c +++ b/src/node_device/node_device_udev.c @@ -1759,7 +1759,7 @@ udevHandleOneDevice(struct udev_device *device) VIR_DEBUG("udev action: '%s': %s", action, udev_device_get_syspath(device)); - if (STREQ(action, "add") || STREQ(action, "change")) + if (STREQ(action, "bind") || STREQ(action, "change")) return udevAddOneDevice(device); if (STREQ(action, "remove")) -- 2.37.2
