Hi, the issue was first reported at vdr-portal.de https://www-vdr--portal-de.translate.goog/forum/index.php?thread/136541-empfehlung-dvb-s2-tuner-oder-satip/&postID=1376196&_x_tr_sl=de&_x_tr_tl=en&_x_tr_hl=de&_x_tr_pto=wapp#post1376196 we've got around a highly critical bug in the xhci driver. https://sundtek.de/support/uxvd32.txt In xhci.c The bug is still active in Mainline: https://github.com/torvalds/linux/blob/master/drivers/usb/host/xhci.c#L2382 static int xhci_check_bw_table(struct xhci_hcd *xhci, struct xhci_virt_device *virt_dev, int old_active_eps) bw_table can end up with a NULL pointer. This problem will lead to a complete kernel crash, rendering the entire system unusable without any access to the actual linux system. How to trigger the problem? Short D+/D- or pull them to ground on a USB device while connecting the device. The problem can happen due to following cases: * a device is getting suddenly disconnected during enumeration * a faulty cable * a faulty device * a malicious device triggers this issue on purpose * if there are electrical issues during connecting a device. A quick hotfix would be to check if bw_table is NULL in xhci_check_bw_table, however the check should be performed earlier - in the area where bw_table is supposed to be assigned. Best Regards, Markus
