Hello Alan Stern, The patch b35c5009bbf6: "USB: EHCI: create per-TT bandwidth tables" from Oct 11, 2013, leads to the following static checker warning: "drivers/usb/host/ehci-sched.c:1377 reserve_release_iso_bandwidth() error: 'tt' dereferencing possible ERR_PTR()" drivers/usb/host/ehci-sched.c 1375 tt = find_tt(stream->ps.udev); ^^^^^^^^^^^^^^^^^^^^^^^^ This can return ERR_PTR(-ENOMEM). 1376 if (sign > 0) 1377 list_add_tail(&stream->ps.ps_list, &tt->ps_list); 1378 else 1379 list_del(&stream->ps.ps_list); 1380 1381 for (i = uframe >> 3; i < EHCI_BANDWIDTH_FRAMES; 1382 i += stream->ps.bw_period) 1383 tt->bandwidth[i] += tt_usecs; Also: drivers/usb/host/ehci-sched.c 257 /* FS/LS bus bandwidth */ 258 if (tt_usecs) { 259 tt = find_tt(qh->ps.udev); ^^^^^^^^^^^^^^^^^^^^^^^^ 260 if (sign > 0) 261 list_add_tail(&qh->ps.ps_list, &tt->ps_list); 262 else 263 list_del(&qh->ps.ps_list); 264 265 for (i = start_uf >> 3; i < EHCI_BANDWIDTH_FRAMES; 266 i += qh->ps.bw_period) 267 tt->bandwidth[i] += tt_usecs; regards, dan carpenter -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html