[PATCH v2 2/2] PCI: endpoint: Fix find_first_zero_bit() usage

From: Niklas Cassel
Date: Fri Nov 17 2017 - 10:01:15 EST


find_first_zero_bit()'s parameter 'size' is defined in bits,
not in bytes.

Calling find_first_zero_bit() with the wrong size unit
will lead to insidious bugs.

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.

Fixes: d74679911610 ("PCI: endpoint: Introduce configfs entry for configuring EP functions")
Signed-off-by: Niklas Cassel <niklas.cassel@xxxxxxxx>
---
drivers/pci/endpoint/pci-ep-cfs.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/pci/endpoint/pci-ep-cfs.c b/drivers/pci/endpoint/pci-ep-cfs.c
index 4f74386c1ced..96b984685640 100644
--- a/drivers/pci/endpoint/pci-ep-cfs.c
+++ b/drivers/pci/endpoint/pci-ep-cfs.c
@@ -108,8 +108,7 @@ static int pci_epc_epf_link(struct config_item *epc_item,
if (ret)
goto err_add_epf;

- func_no = find_first_zero_bit(&epc_group->function_num_map,
- sizeof(epc_group->function_num_map));
+ func_no = ffz(epc_group->function_num_map);
set_bit(func_no, &epc_group->function_num_map);
epf->func_no = func_no;

--
2.14.2