Greg Kroah-Hartman wrote on Fri, Aug 19, 2022 at 05:44:10PM +0200:
From: Sean V Kelley sean.v.kelley@intel.com
[ Upstream commit 05e9ae19ab83881a0f33025bd1288e41e552a34b ]
Consolidate subordinate bus checks with pci_walk_bus() into pci_walk_bridge() for walking below potentially AER affected bridges.
Link: https://lore.kernel.org/r/20201121001036.8560-10-sean.v.kelley@intel.com Tested-by: Jonathan Cameron Jonathan.Cameron@huawei.com # non-native/no RCEC Signed-off-by: Sean V Kelley sean.v.kelley@intel.com Signed-off-by: Bjorn Helgaas bhelgaas@google.com Signed-off-by: Sasha Levin sashal@kernel.org
drivers/pci/pcie/err.c | 30 +++++++++++++++++++++++------- 1 file changed, 23 insertions(+), 7 deletions(-)
diff --git a/drivers/pci/pcie/err.c b/drivers/pci/pcie/err.c index 931e75f2549d..8b53aecdb43d 100644 --- a/drivers/pci/pcie/err.c +++ b/drivers/pci/pcie/err.c [...] @@ -165,23 +182,22 @@ pci_ers_result_t pcie_do_recovery(struct pci_dev *dev, else bridge = pci_upstream_bridge(dev);
- bus = bridge->subordinate; pci_dbg(bridge, "broadcast error_detected message\n"); if (state == pci_channel_io_frozen) {
pci_walk_bus(bus, report_frozen_detected, &status);
pci_walk_bridge(bridge, report_frozen_detected, &status);
A local conflict merging this made me notice a later commit: ----- commit 387c72cdd7fb6bef650fb078d0f6ae9682abf631 Author: Keith Busch kbusch@kernel.org Date: Mon Jan 4 15:02:58 2021 -0800
PCI/ERR: Retain status from error notification
Overwriting the frozen detected status with the result of the link reset loses the NEED_RESET result that drivers are depending on for error handling to report the .slot_reset() callback. Retain this status so that subsequent error handling has the correct flow.
Link: https://lore.kernel.org/r/20210104230300.1277180-4-kbusch@kernel.org Reported-by: Hinko Kocevar hinko.kocevar@ess.eu Tested-by: Hedi Berriche hedi.berriche@hpe.com Signed-off-by: Keith Busch kbusch@kernel.org Signed-off-by: Bjorn Helgaas bhelgaas@google.com Acked-by: Sean V Kelley sean.v.kelley@intel.com Acked-by: Hedi Berriche hedi.berriche@hpe.com
diff --git a/drivers/pci/pcie/err.c b/drivers/pci/pcie/err.c index a84f0bf4c1e2..b576aa890c76 100644 --- a/drivers/pci/pcie/err.c +++ b/drivers/pci/pcie/err.c @@ -198,8 +198,7 @@ pci_ers_result_t pcie_do_recovery(struct pci_dev *dev, pci_dbg(bridge, "broadcast error_detected message\n"); if (state == pci_channel_io_frozen) { pci_walk_bridge(bridge, report_frozen_detected, &status); - status = reset_subordinates(bridge); - if (status != PCI_ERS_RESULT_RECOVERED) { + if (reset_subordinates(bridge) != PCI_ERS_RESULT_RECOVERED) { pci_warn(bridge, "subordinate device reset failed\n"); goto failed; } -----
Since this (commit I reply to) has been picked up, I think it'd make sense to also include this (commit I just listed) in a later 5.10 tag. It cherry-picks without error but would you like me to resend? (I have added in Cc all involved people to this mail)
Digging through the mails the patch came with seem to imply approval for stable merges; but it didn't make sense until pci_walk_bridge() had been added just now. Now it's here we probably want both: https://lore.kernel.org/all/d9ee4151-b28d-a52a-b5be-190a75e0e49b@intel.com/
(I noticed because the NXP kernel we are provided includes a different "fix" for what I believe to be the same issue, previously discussed here: https://lore.kernel.org/linux-pci/12115.1588207324@famine/
I haven't actually encountered any of the problems discribed, so this is purely theorical for me; it just looks a bit weird.)
Thanks, -- Dominique