• Gabriele Paoloni's avatar
    PCI/AER: Report non-fatal errors only to the affected endpoint · 86acc790
    Gabriele Paoloni authored
    Previously, if an non-fatal error was reported by an endpoint, we
    called report_error_detected() for the endpoint, every sibling on the
    bus, and their descendents.  If any of them did not implement the
    .error_detected() method, do_recovery() failed, leaving all these
    devices unrecovered.
    
    For example, the system described in the bugzilla below has two devices:
    
      0000:74:02.0 [19e5:a230] SAS controller, driver has .error_detected()
      0000:74:03.0 [19e5:a235] SATA controller, driver lacks .error_detected()
    
    When a device such as 74:02.0 reported a non-fatal error, do_recovery()
    failed because 74:03.0 lacked an .error_detected() method.  But per PCIe
    r3.1, sec 6.2.2.2.2, such an error does not compromise the Link and
    does not affect 74:03.0:
    
      Non-fatal errors are uncorrectable errors which cause a particular
      transaction to be unreliable but the Link is otherwise fully functional.
      Isolating Non-fatal from Fatal errors provides Requester/Receiver logic
      in a device or system management software the opportunity to recover from
      the error without resetting the components on the Link and disturbing
      other transactions in progress.  Devices not associated with the
      transaction in error are not impacted by the error.
    
    Report non-fatal errors only to the endpoint that reported them.  We really
    want to check for AER_NONFATAL here, but the current code structure doesn't
    allow that.  Looking for pci_channel_io_normal is the best we can do now.
    
    Link: https://bugzilla.kernel.org/show_bug.cgi?id=197055
    Fixes: 6c2b374d ("PCI-Express AER implemetation: AER core and aerdriver")
    Signed-off-by: default avatarGabriele Paoloni <gabriele.paoloni@huawei.com>
    Signed-off-by: default avatarDongdong Liu <liudongdong3@huawei.com>
    [bhelgaas: changelog]
    Signed-off-by: default avatarBjorn Helgaas <bhelgaas@google.com>
    86acc790
aerdrv_core.c 21.7 KB