As reported in the below link, it seems older versions of gcc cannot
determine that the howmany variable is known for all callers. Include
a test so that newer compilers can enforce this sanity check and older
compilers can still work. Add __always_inline attribute to give the
compiler an even better chance to know the inputs.
Fixes: 4453f360862e ("PCI: Batch BAR sizing operations")
Link: https://lore.kernel.org/all/20250209154512.GA18688@xxxxxxxxxx
Reported-by: Oleg Nesterov <oleg@xxxxxxxxxx>
Tested-by: Oleg Nesterov <oleg@xxxxxxxxxx>
Tested-by: Mitchell Augustin <mitchell.augustin@xxxxxxxxxxxxx>
Signed-off-by: Alex Williamson <alex.williamson@xxxxxxxxxx>
---
v2:
- Switch to statically_true (David Laight)
- Add __always_inline (David Laight)
- Included Tested-by reports
drivers/pci/probe.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index b6536ed599c3..246744d8d268 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -339,13 +339,14 @@ int __pci_read_base(struct pci_dev *dev, enum pci_bar_type type,
return (res->flags & IORESOURCE_MEM_64) ? 1 : 0;
}
-static void pci_read_bases(struct pci_dev *dev, unsigned int howmany, int rom)
+static __always_inline void pci_read_bases(struct pci_dev *dev,
+ unsigned int howmany, int rom)
{
u32 rombar, stdbars[PCI_STD_NUM_BARS];
unsigned int pos, reg;
u16 orig_cmd;
- BUILD_BUG_ON(howmany > PCI_STD_NUM_BARS);
+ BUILD_BUG_ON(statically_true(howmany > PCI_STD_NUM_BARS));
if (dev->non_compliant_bars)
return;
--
2.48.1
