[+cc linux-pci] On Fri, Feb 19, 2016 at 4:09 AM, Jean Delvare <jdelvare@xxxxxxx> wrote: > On Wed, 17 Feb 2016 11:03:31 -0600, Bjorn Helgaas wrote: >> [+cc Huang, author of both aer_inject and apei/einj] >> >> On Wed, Feb 17, 2016 at 7:33 AM, Jean Delvare <jdelvare@xxxxxxx> wrote: >> > Hi all, >> > >> > I am looking for some guidance regarding AER testing. I see that we >> > have two different drivers for error injection in the kernel: >> > aer_inject and apei/einj. The user-space aer-inject tool seems to only >> > care about the former. >> > >> > How does one know which driver should be used on a given system? I >> > suppose that only one of them will work on a given system? >> > >> > My impression is that aer_inject is for "native" AER handling while >> > apei/einj is for ACPI-driven AER. Is it correct? If not I would >> > appreciate some pointers explaining when aer_inject should be used and >> > when apei/einj should be used. >> >> My understanding is that: >> >> - aer_inject does not actually write to any hardware registers >> itself (though I do see it writes to some masks). It works by >> replacing the PCI config accessors with new ones that make it look >> like the AER registers have errors logged. >> >> - apei/einj runs ACPI methods that apparently seed errors. These >> might use hardware support for seeding errors, which would of course >> be platform-dependent. >> >> So aer_inject should work on any system at all. I think apei/einj > > My problem is precisely that aer_inject doesn't work on any system I > tested. Either the device doesn't support AER, or its root port doesn't > support AER, or (further I've been) the "error device" of the root port > doesn't exist. OK, I should have said "aer_inject" should work on any system with devices that support AER :) And there are also some conditions related to _OSC and "firmware-first" error handling, based on the HEST table. I expect that dmesg would show whether we can use AER and why it might be disabled (and if dmesg doesn't show that, it *should*). > I am not too familiar with PCIe but apparently PCIe > devices can have "sub-devices" which do not show in "lspci" but show up > in /sys/bus/pci_express/devices. I have yet to see an aer sub-device > there on any of my systems. Yes, the different PCIe services (AER, native hotplug, VC, etc.) are handled sort of like subdevices. This seems a bit hacky to me but it's what we have. Anyway, if you have a system where the root port and a device below it support AER, but there's no subdevice for it, we must have disabled it somehow. Can you collect a dmesg and "lspci -vv" for it? We should be logging a clue there. >> will only work if the platform supplies an EINJ table, and even when >> it does, I suspect different platforms probably have different >> injection capabilities. >> >> Huang probably can give a much better response. > > Huang, pleeeease? :) > > -- > Jean Delvare > SUSE L3 Support -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
