On 06/19/2018 04:57 PM, Bjorn Helgaas wrote: > On Wed, May 16, 2018 at 05:12:21PM -0600, Keith Busch wrote: >> On Wed, May 16, 2018 at 06:44:22PM -0400, Sinan Kaya wrote: >>> On 5/16/2018 5:33 PM, Alexandru Gagniuc wrote: >>>> AER status bits are sticky, and they survive system resets. Downstream >>>> devices are usually taken care of after re-enumerating the downstream >>>> busses, as the AER bits are cleared during probe(). >>>> >>>> However, nothing clears the bits of the port which contained the >>>> error. These sticky bits may leave some BIOSes to think that something >>>> bad happened, and print ominous messages on next boot. To prevent this, >>>> tidy up the AER status bits before releasing containment. >>>> >>>> Signed-off-by: Alexandru Gagniuc <mr.nuke.me@xxxxxxxxx> >>>> --- >>>> drivers/pci/pcie/dpc.c | 4 ++++ >>>> 1 file changed, 4 insertions(+) >>>> >>>> diff --git a/drivers/pci/pcie/dpc.c b/drivers/pci/pcie/dpc.c >>>> index 8c57d607e603..bf82d6936556 100644 >>>> --- a/drivers/pci/pcie/dpc.c >>>> +++ b/drivers/pci/pcie/dpc.c >>>> @@ -112,6 +112,10 @@ static void dpc_work(struct work_struct *work) >>>> dpc->rp_pio_status = 0; >>>> } >>>> >>>> + /* DPC event made a mess of our AER status bits. Clean them up. */ >>>> + pci_cleanup_aer_error_status_regs(pdev); >>>> + /* TODO: Should we also use aer_print_error to log the event? */ >>>> + >>>> pci_write_config_word(pdev, cap + PCI_EXP_DPC_STATUS, >>>> PCI_EXP_DPC_STATUS_TRIGGER | PCI_EXP_DPC_STATUS_INTERRUPT); >>>> >>>> >>> >>> I think Keith has a patch to fix this. It was under review at some point. >> >> Right, I do intend to following up on this, but I've had some trouble >> finding time the last few weeks. Sorry about that, things will clear up >> for me shortly. > > I'll drop this (Alexandru's) patch for now, waiting for your update, Keith. I wonder if clearing AER status bits is mutually exclusive with refactoring other parts of DPC handling? Alex
