Please follow Bjorn's request for patch formatting: https://marc.info/?l=linux-pci&m=150905742808166&w=2 I would mention in the commit title that this is a fix. eg "PCI: designware-ep: Fix find_first_zero_bit() usage" On Thu, Nov 16, 2017 at 07:34:38PM +0100, Niklas Cassel wrote: > find_first_zero_bit()'s parameter 'size' is defined in bits, > not in bytes. > > find_first_zero_bit() was called with bytes rather than bits, "was called with size in bytes"... > which thus defined a too low upper limit, causing > dw_pcie_ep_inbound_atu() to assign iatu index #4 to both bar 4 > and bar 5, which made bar 5 overwrite the settings set by bar 4. > > ./pcitest.sh > BAR tests > BAR0: OKAY > BAR1: OKAY > BAR2: OKAY > BAR3: OKAY > BAR4: NOT OKAY > BAR5: OKAY Sorry but this example is pretty much useless - either you add a self-explanatory kernel log or you just remove it. > Fix this by using replacing find_first_zero_bit() with ffz(), > since ffz() only works on a single 'unsigned long' and therefore > does not need a size argument. > > Signed-off-by: Niklas Cassel <niklas.cassel@xxxxxxxx> We need a Fixes: tag at least, see Bjorn's post above. Thanks, Lorenzo > --- > drivers/pci/dwc/pcie-designware-ep.c | 6 ++---- > 1 file changed, 2 insertions(+), 4 deletions(-) > > diff --git a/drivers/pci/dwc/pcie-designware-ep.c b/drivers/pci/dwc/pcie-designware-ep.c > index d53d5f168363..ab9a9e160daf 100644 > --- a/drivers/pci/dwc/pcie-designware-ep.c > +++ b/drivers/pci/dwc/pcie-designware-ep.c > @@ -70,8 +70,7 @@ static int dw_pcie_ep_inbound_atu(struct dw_pcie_ep *ep, enum pci_barno bar, > u32 free_win; > struct dw_pcie *pci = to_dw_pcie_from_ep(ep); > > - free_win = find_first_zero_bit(&ep->ib_window_map, > - sizeof(ep->ib_window_map)); > + free_win = ffz(ep->ib_window_map); > if (free_win >= ep->num_ib_windows) { > dev_err(pci->dev, "no free inbound window\n"); > return -EINVAL; > @@ -96,8 +95,7 @@ static int dw_pcie_ep_outbound_atu(struct dw_pcie_ep *ep, phys_addr_t phys_addr, > u32 free_win; > struct dw_pcie *pci = to_dw_pcie_from_ep(ep); > > - free_win = find_first_zero_bit(&ep->ob_window_map, > - sizeof(ep->ob_window_map)); > + free_win = ffz(ep->ob_window_map); > if (free_win >= ep->num_ob_windows) { > dev_err(pci->dev, "no free outbound window\n"); > return -EINVAL; > -- > 2.14.2 >
