linux.git/arch/powerpc/kernel/eeh.c, branch v3.11

powerpc/eeh: Add missing procfs entry for PowerNV

2013-08-09T08:06:47+00:00

The procfs entry for global statistics has been missed on PowerNV
platform and the patch is going to add that.

Signed-off-by: Mike Qiu 
Acked-by: Gavin Shan 
Signed-off-by: Benjamin Herrenschmidt

powerpc/eeh: Introdce flag to protect sysfs

2013-07-24T04:18:49+00:00

The patch introduces flag EEH_DEV_SYSFS to keep track that the sysfs
entries for the corresponding EEH device (then PCI device) has been
added or removed, in order to avoid race condition.

Signed-off-by: Gavin Shan 
Signed-off-by: Benjamin Herrenschmidt

powerpc/eeh: Use partial hotplug for EEH unaware drivers

2013-07-24T04:18:48+00:00

When EEH error happens to one specific PE, some devices with drivers
supporting EEH won't except hotplug on the device. However, there
might have other deivces without driver, or with driver without EEH
support. For the case, we need do partial hotplug in order to make
sure that the PE becomes absolutely quite during reset. Otherise,
the PE reset might fail and leads to failure of error recovery.

The current code doesn't handle that 'mixed' case properly, it either
uses the error callbacks to the drivers, or tries hotplug, but doesn't
handle a PE (EEH domain) composed of a combination of the two.

The patch intends to support so-called "partial" hotplug for EEH:
Before we do reset, we stop and remove those PCI devices without
EEH sensitive driver. The corresponding EEH devices are not detached
from its PE, but with special flag. After the reset is done, those
EEH devices with the special flag will be scanned one by one.

Signed-off-by: Gavin Shan 
Signed-off-by: Benjamin Herrenschmidt

powerpc/eeh: Use safe list traversal when walking EEH devices

2013-07-24T04:18:47+00:00

Currently, we're trasversing the EEH devices list using list_for_each_entry().
That's not safe enough because the EEH devices might be removed from
its parent PE while doing iteration. The patch replaces that with
list_for_each_entry_safe().

Signed-off-by: Gavin Shan 
Signed-off-by: Benjamin Herrenschmidt

powerpc/eeh: Keep PE during hotplug

2013-07-24T04:18:47+00:00

When we do normal hotplug, the PE (shadow EEH structure) shouldn't be
kept around.

However, we need to keep it if the hotplug an artifial one caused by
EEH errors recovery.

Since we remove EEH device through the PCI hook pcibios_release_device(),
the flag "purge_pe" passed to various functions is meaningless. So the patch
removes the meaningless flag and introduce new flag "EEH_PE_KEEP"
to save the PE while doing hotplug during EEH error recovery.

Signed-off-by: Gavin Shan 
Signed-off-by: Benjamin Herrenschmidt

powerpc/eeh: Export functions for hotplug

2013-07-24T04:18:46+00:00

Make some functions public in order to support hotplug on either specific
PCI bus or PCI device in future.

Signed-off-by: Gavin Shan 
Signed-off-by: Benjamin Herrenschmidt

powerpc/eeh: Remove reference to PCI device

2013-07-24T04:18:46+00:00

We will rely on pcibios_release_device() to remove the EEH cache
and unbind EEH device for the specific PCI device. So we shouldn't
hold the reference to the PCI device from EEH cache and EEH device.
Otherwise, pcibios_release_device() won't be called as we expected.
The patch removes the reference to the PCI device in EEH core.

Signed-off-by: Gavin Shan 
Signed-off-by: Benjamin Herrenschmidt

powerpc/eeh: Avoid build warnings

2013-07-01T01:10:33+00:00

The patch is for avoiding following build warnings:

   The function .pnv_pci_ioda_fixup() references
   the function __init .eeh_init().
   This is often because .pnv_pci_ioda_fixup lacks a __init

   The function .pnv_pci_ioda_fixup() references
   the function __init .eeh_addr_cache_build().
   This is often because .pnv_pci_ioda_fixup lacks a __init

Signed-off-by: Gavin Shan 
Signed-off-by: Benjamin Herrenschmidt

powerpc/eeh: Refactor the output message

2013-07-01T01:10:33+00:00

We needn't the the whole backtrace other than one-line message in
the error reporting interrupt handler. For errors triggered by
access PCI config space or MMIO, we replace "WARN(1, ...)" with
pr_err() and dump_stack(). The patch also adds more output messages
to indicate what EEH core is doing. Besides, some printk() are
replaced with pr_warning().

Signed-off-by: Gavin Shan 
Signed-off-by: Benjamin Herrenschmidt

powerpc/eeh: Don't collect PCI-CFG data on PHB

2013-07-01T01:10:31+00:00

When the PHB is fenced or dead, it's pointless to collect the data
from PCI config space of subordinate PCI devices since it should
return 0xFF's. The patch also fixes overwritten buffer while getting
PCI config data.

Signed-off-by: Gavin Shan 
Signed-off-by: Benjamin Herrenschmidt