On 3/17/23 01:34, Rick Wertenbroek wrote: >>> By the way, enabling the interrupts to see the error notifications, I do see a >>> lot of retry timeout and other recoverable errors. So the issues I am seeing >>> could be due to my PCI cable setup that is not ideal (bad signal, ground loops, >>> ... ?). Not sure. I do not have a PCI analyzer handy :) > > I have enabled the IRQs and messages thanks to your patches but I don't get > messages from the IRQs (it seems no IRQs are fired). My PCIe link seems stable. > The main issue I face is still that after a random amount of time, the BARs are > reset to 0, I don't have a PCIe analyzer so I cannot chase config space TLPs > (e.g., host writing the BAR values to the config header), but I don't think that > the problem comes from a TLP issued from the host. (it might be). Hmmm... I am getting lots of IRQs, especially the ones signaling "replay timer timed out" and "replay timer rolled over after 4 transmissions of the same TLP" but also some "phy error detected on receive side"... Need to try to rework my cable setup I guess. As for the BARs being reset to 0, I have not checked, but it may be why I see things not working after some inactivity. Will check that. We may be seeing the same regarding that. > I don't think it's a buffer overflow / out-of-bounds access by kernel > code for two reasons > 1) The values in the config space around the BARs is coherent and unchanged > 2) The bars are reset to 0 and not a random value > > I suspect a hardware reset of those registers issued internally in the > PCIe controller, > I don't know why (it might be a link related event or power state > related event). > > I have also experienced very slow behavior with the PCI endpoint test driver, > e.g., pcitest -w 1024 -d would take tens of seconds to complete. It seems to > come from LCRC errors, when I check the "LCRC Error count register" > @0xFD90'0214 I can see it drastically increase between two calls of pcitest > (when I mean drastically it means by 6607 (0x19CF) for example). > > The "ECC Correctable Error Count Register" @0xFD90'0218 reads 0 though. > > I have tried to shorten the cabling by removing one of the PCIe extenders, that > didn't change the issues much. > > Any ideas as to why I see a large number of TLPs with LCRC errors in them ? > Do you experience the same ? What are your values in 0xFD90'0214 when > running e.g., pcitest -w 1024 -d (note: you can reset the counter by writing > 0xFFFF to it in case it reaches the maximum value of 0xFFFF). I have not checked. But I will look at these counters to see what I have there. -- Damien Le Moal Western Digital Research
