[RFC 0/2] PCI: acpiphp: workaround race between hotplug and SCSI_SCAN_ASYNC job

[Igor Mammedov <imammedo@redhat.com>]

Hacks to mask a race between HBA scan job and bridge re-configuration(s)
during hotplug. 

I don't like it a bit but it something that could be done quickly
and solves problems that were reported.

Other options to discuss/possibly more invasive:
 1: make sure pci_assign_unassigned_bridge_resources() doesn't reconfigure
    bridge if it's not necessary.
 2. make SCSI_SCAN_ASYNC job wait till hotplug is finished for all slots on
    the bridge or somehow restart the job if it fails
 3. any other ideas?


1st reported: https://lore.kernel.org/r/9eb669c0-d8f2-431d-a700-6da13053ae54@proxmox.com

CC: Dongli Zhang <dongli.zhang@oracle.com>
CC: linux-acpi@vger.kernel.org
CC: linux-pci@vger.kernel.org
CC: imammedo@redhat.com
CC: mst@redhat.com
CC: rafael@kernel.org
CC: lenb@kernel.org
CC: bhelgaas@google.com
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CC: stable@vger.kernel.org
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CC: Fiona Ebner <f.ebner@proxmox.com>
CC: Thomas Lamprecht <t.lamprecht@proxmox.com>

Igor Mammedov (2):
  PCI: acpiphp: enable slot only if it hasn't been enabled already
  PCI: acpiphp: slowdown hotplug if hotplugging multiple devices at a
    time

 drivers/pci/hotplug/acpiphp_glue.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

-- 
2.39.3