re: PCI: Add TLP Prefix reading to pcie_read_tlp_log()

[Colin King (gmail)]

Hi,

Static analysis shows there is a potential issue in the following commit:

commit 00048c2d5f113bb4e82a0a30dfc4ee12590b81f5
Author: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx>
Date:   Tue Jan 14 19:08:39 2025 +0200

    PCI: Add TLP Prefix reading to pcie_read_tlp_log()


The issue is described as follows:

unsigned int aer_tlp_log_len(struct pci_dev *dev, u32 aercc)
{
        return PCIE_STD_NUM_TLP_HEADERLOG +
               (aercc & PCI_ERR_CAP_PREFIX_LOG_PRESENT) ?
               dev->eetlp_prefix_max : 0;
}


static analysis is warning that the left hand size of the ? operator is 
always true and so dev->eetlp_prefix_max is always being returned and 
the 0 is never returned (dead code).

I suspect the expected behaviour is as follows:

        return PCIE_STD_NUM_TLP_HEADERLOG +
               ((aercc & PCI_ERR_CAP_PREFIX_LOG_PRESENT) ?
               dev->eetlp_prefix_max : 0);

..I'm reluctant to send a fix in case this is not the original intention.

Colin

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