gwj / at91sam9263 · Commits

Commit 554962405cb18a3e624edf05b6257eaf9273810c

Authored by Mark McLoughlin
Committed by Anthony Liguori
1 parent 1fa63e43

Prefer sysfs for USB host devices 

Scanning for devices via /sys/bus/usb/devices/ and using them via the
/dev/bus/usb/<bus>/<device> character devices is the prefered method
on modern kernels, so try that first.

When using SELinux and libvirt, qemu will have access to /sys/bus/usb
but not /proc/bus/usb, so although the current code will work just
fine, it will generate SELinux AVC warnings.

See also:

  https://bugzilla.redhat.com/508326

Reported-by: Daniel Berrange <berrange@redhat.com>
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Inline Side-by-side
Showing 1 changed file with 9 additions and 9 deletions
usb-linux.c
  View file @5549624
... ... @@ -1265,6 +1265,15 @@ static int usb_host_scan(void *opaque, USBScanFunc *func)
1265 1265  
1266 1266 /* only check the host once */
1267 1267 if (!usb_fs_type) {
  1268 + dir = opendir(USBSYSBUS_PATH "/devices");
  1269 + if (dir) {
  1270 + /* devices found in /dev/bus/usb/ (yes - not a mistake!) */
  1271 + strcpy(devpath, USBDEVBUS_PATH);
  1272 + usb_fs_type = USB_FS_SYS;
  1273 + closedir(dir);
  1274 + dprintf(USBDBG_DEVOPENED, USBSYSBUS_PATH);
  1275 + goto found_devices;
  1276 + }
1268 1277 f = fopen(USBPROCBUS_PATH "/devices", "r");
1269 1278 if (f) {
1270 1279 /* devices found in /proc/bus/usb/ */
... ... @@ -1284,15 +1293,6 @@ static int usb_host_scan(void *opaque, USBScanFunc *func)
1284 1293 dprintf(USBDBG_DEVOPENED, USBDEVBUS_PATH);
1285 1294 goto found_devices;
1286 1295 }
1287   - dir = opendir(USBSYSBUS_PATH "/devices");
1288   - if (dir) {
1289   - /* devices found in /dev/bus/usb/ (yes - not a mistake!) */
1290   - strcpy(devpath, USBDEVBUS_PATH);
1291   - usb_fs_type = USB_FS_SYS;
1292   - closedir(dir);
1293   - dprintf(USBDBG_DEVOPENED, USBSYSBUS_PATH);
1294   - goto found_devices;
1295   - }
1296 1296 found_devices:
1297 1297 if (!usb_fs_type) {
1298 1298 monitor_printf(mon, "husb: unable to access USB devices\n");
... ...