This is a note to let you know that I've just added the patch titled

    PCI: Mark Atheros AR93xx to avoid bus reset

to the 3.18-stable tree which can be found at:
    
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     pci-mark-atheros-ar93xx-to-avoid-bus-reset.patch
and it can be found in the queue-3.18 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <[email protected]> know about it.


>From c3e59ee4e76686b0c84ca8faa1011d10cd4ca1b8 Mon Sep 17 00:00:00 2001
From: Alex Williamson <[email protected]>
Date: Thu, 15 Jan 2015 18:17:12 -0600
Subject: PCI: Mark Atheros AR93xx to avoid bus reset

From: Alex Williamson <[email protected]>

commit c3e59ee4e76686b0c84ca8faa1011d10cd4ca1b8 upstream.

Reports against the TL-WDN4800 card indicate that PCI bus reset of this
Atheros device cause system lock-ups and resets.  I've also been able to
confirm this behavior on multiple systems.  The device never returns from
reset and attempts to access config space of the device after reset result
in hangs.  Blacklist bus reset for the device to avoid this issue.

[bhelgaas: This regression appeared in v3.14.  Andreas bisected it to
425c1b223dac ("PCI: Add Virtual Channel to save/restore support"), but we
don't understand the mechanism by which that commit affects the reset
path.]

[bhelgaas: changelog, references]
Link: http://lkml.kernel.org/r/[email protected]
Reported-by: Andreas Hartmann <[email protected]>
Tested-by: Andreas Hartmann <[email protected]>
Signed-off-by: Alex Williamson <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 drivers/pci/quirks.c |   14 ++++++++++++++
 1 file changed, 14 insertions(+)

--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -3008,6 +3008,20 @@ DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_R
 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_MELLANOX, PCI_ANY_ID,
                         quirk_broken_intx_masking);
 
+static void quirk_no_bus_reset(struct pci_dev *dev)
+{
+       dev->dev_flags |= PCI_DEV_FLAGS_NO_BUS_RESET;
+}
+
+/*
+ * Atheros AR93xx chips do not behave after a bus reset.  The device will
+ * throw a Link Down error on AER-capable systems and regardless of AER,
+ * config space of the device is never accessible again and typically
+ * causes the system to hang or reset when access is attempted.
+ * http://www.spinics.net/lists/linux-pci/msg34797.html
+ */
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_ATHEROS, 0x0030, quirk_no_bus_reset);
+
 #ifdef CONFIG_ACPI
 /*
  * Apple: Shutdown Cactus Ridge Thunderbolt controller.


Patches currently in stable-queue which might be from 
[email protected] are

queue-3.18/pci-add-flag-for-devices-where-we-can-t-use-bus-reset.patch
queue-3.18/pci-mark-atheros-ar93xx-to-avoid-bus-reset.patch
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