[PATCH 1/1] PCI/RCEC: Fix failure to inject errors to some RCiEP devices

From: Qiuxu Zhuo
Date: Tue Feb 09 2021 - 21:31:52 EST


On a Sapphire Rapids server, it failed to inject correctable errors
to the RCiEP device e8:02.0 which was associated with the RCEC device
e8:00.4. See the following error log before applying the patch:

aer-inject -s e8:02.0 examples/correctable
Error: Failed to write, No such device

This was because rcec_assoc_rciep() mistakenly used "rciep->devfn" as
device number to check whether the corresponding bit was set in
the RCiEPBitmap of the RCEC. So that the RCiEP device e8:02.0 wasn't
linked to the RCEC and resulted in the above error.

Fix it by using PCI_SLOT() to convert rciep->devfn to device number.
Ensure that the RCiEP devices associated with the RCEC are linked to
the RCEC as the RCEC is enumerated. After applying the patch, correctable
errors can be injected to the RCiEP successfully.

Reported-and-tested-by: Wen Jin <wen.jin@xxxxxxxxx>
Signed-off-by: Qiuxu Zhuo <qiuxu.zhuo@xxxxxxxxx>
---
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