On Wed, May 31, 2023 at 04:30:28PM -0500, Bjorn Helgaas wrote: > On Wed, May 31, 2023 at 08:48:35PM +0200, Jonas Gorski wrote: ... > > Looking at the code I understand where coverity is coming from: > > > > #define __pci_dev_for_each_res0(dev, res, ...) \ > > for (unsigned int __b = 0; \ > > res = pci_resource_n(dev, __b), __b < PCI_NUM_RESOURCES; \ > > __b++) > > > > res will be assigned before __b is checked for being less than > > PCI_NUM_RESOURCES, making it point to behind the array at the end of > > the last loop iteration. > > > > Rewriting the test expression as > > > > __b < PCI_NUM_RESOURCES && (res = pci_resource_n(dev, __b)); > > > > should avoid the (coverity) warning by making use of lazy evaluation. > > > > It probably makes the code slightly less performant as res will now be > > checked for being not NULL (which will always be true), but I doubt it > > will be significant (or in any hot paths). > > Thanks a lot for looking into this! I think you're right, and I think > the rewritten expression is more logical as well. Do you want to post > a patch for it? Gimme some time, I was on a long leave and now it's a pile to handle. -- With Best Regards, Andy Shevchenko
