On Mon, Feb 22, 2021 at 09:17:17AM +0800, Qiuxu Zhuo wrote:
> Function rcec_assoc_rciep() incorrectly used "rciep->devfn" (a single
> byte encoding the device and function number) as the device number to
> check whether the corresponding bit was set in the RCiEPBitmap of the
> RCEC (Root Complex Event Collector) while enumerating over each bit of
> the RCiEPBitmap.
>
> As per the PCI Express Base Specification, Revision 5.0, Version 1.0,
> Section 7.9.10.2, "Association Bitmap for RCiEPs", p. 935, only needs to
> use a device number to check whether the corresponding bit was set in
> the RCiEPBitmap.
>
> Fix rcec_assoc_rciep() using the PCI_SLOT() macro and convert the value
> of "rciep->devfn" to a device number to ensure that the RCiEP devices
> associated with the RCEC are linked when the RCEC is enumerated.
>
> Fixes: 507b460f8144 ("PCI/ERR: Add pcie_link_rcec() to associate RCiEPs")
> Reported-and-tested-by: Wen Jin <wen.jin@xxxxxxxxx>
> Reviewed-by: Sean V Kelley <sean.v.kelley@xxxxxxxxx>
> Signed-off-by: Qiuxu Zhuo <qiuxu.zhuo@xxxxxxxxx>
I think 507b460f8144 appeared in v5.11, so not something we broke in
v5.12. Applied to pci/error for v5.13, thanks!
If I understand correctly, we previously only got this right in one
case:
0 == PCI_SLOT(00.0) # correct
1 == PCI_SLOT(00.1) # incorrect
2 == PCI_SLOT(00.2) # incorrect
...
8 == PCI_SLOT(01.0) # incorrect
9 == PCI_SLOT(01.1) # incorrect
...
31 == PCI_SLOT(03.7) # incorrect
> ---
> v2->v3:
> Drop "[ Krzysztof: Update commit message. ]" from the commit message
>
> drivers/pci/pcie/rcec.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/pci/pcie/rcec.c b/drivers/pci/pcie/rcec.c
> index 2c5c552994e4..d0bcd141ac9c 100644
> --- a/drivers/pci/pcie/rcec.c
> +++ b/drivers/pci/pcie/rcec.c
> @@ -32,7 +32,7 @@ static bool rcec_assoc_rciep(struct pci_dev *rcec, struct pci_dev *rciep)
>
> /* Same bus, so check bitmap */
> for_each_set_bit(devn, &bitmap, 32)
> - if (devn == rciep->devfn)
> + if (devn == PCI_SLOT(rciep->devfn))
> return true;
>
> return false;
> --
> 2.17.1
>
