Even though it is not expected, and would trigger a WARN_ON, killing a transfer in a uninitialized slot this sequence is warned by clang analyzer, twice: drivers/usb/isp1760/isp1760-hcd.c:1976:18: warning: The result of the left shift is undefined because the right operand is negative [clang-analyzer-core.UndefinedBinaryOperatorResult] skip_map |= (1 << qh->slot); drivers/usb/isp1760/isp1760-hcd.c:1983:18: warning: The result of the left shift is undefined because the right operand is negative [clang-analyzer-core.UndefinedBinaryOperatorResult] skip_map |= (1 << qh->slot); Only set skip map if slot is active. Signed-off-by: Rui Miguel Silva <rui.silva@xxxxxxxxxx> --- drivers/usb/isp1760/isp1760-hcd.c | 18 +++++++++++------- 1 file changed, 11 insertions(+), 7 deletions(-) diff --git a/drivers/usb/isp1760/isp1760-hcd.c b/drivers/usb/isp1760/isp1760-hcd.c index aed2714ce0cf..bf8ab3fe2e5a 100644 --- a/drivers/usb/isp1760/isp1760-hcd.c +++ b/drivers/usb/isp1760/isp1760-hcd.c @@ -1974,16 +1974,20 @@ static void kill_transfer(struct usb_hcd *hcd, struct urb *urb, /* We need to forcefully reclaim the slot since some transfers never return, e.g. interrupt transfers and NAKed bulk transfers. */ if (usb_pipecontrol(urb->pipe) || usb_pipebulk(urb->pipe)) { - skip_map = isp1760_hcd_read(hcd, HC_ATL_PTD_SKIPMAP); - skip_map |= (1 << qh->slot); - isp1760_hcd_write(hcd, HC_ATL_PTD_SKIPMAP, skip_map); - ndelay(100); + if (qh->slot != -1) { + skip_map = isp1760_hcd_read(hcd, HC_ATL_PTD_SKIPMAP); + skip_map |= (1 << qh->slot); + isp1760_hcd_write(hcd, HC_ATL_PTD_SKIPMAP, skip_map); + ndelay(100); + } priv->atl_slots[qh->slot].qh = NULL; priv->atl_slots[qh->slot].qtd = NULL; } else { - skip_map = isp1760_hcd_read(hcd, HC_INT_PTD_SKIPMAP); - skip_map |= (1 << qh->slot); - isp1760_hcd_write(hcd, HC_INT_PTD_SKIPMAP, skip_map); + if (qh->slot != -1) { + skip_map = isp1760_hcd_read(hcd, HC_INT_PTD_SKIPMAP); + skip_map |= (1 << qh->slot); + isp1760_hcd_write(hcd, HC_INT_PTD_SKIPMAP, skip_map); + } priv->int_slots[qh->slot].qh = NULL; priv->int_slots[qh->slot].qtd = NULL; } -- 2.33.0