linux-stable.git/arch/powerpc/kernel/eeh_driver.c, branch linux-4.7.y

powerpc/eeh: Fix wrong argument passed to eeh_rmv_device()

2016-06-28T10:47:49+00:00

When calling eeh_rmv_device() in eeh_reset_device() for partial hotplug
case, @rmv_data instead of its address is the proper argument.
Otherwise, the stack frame is corrupted when writing to
@rmv_data (actually its address) in eeh_rmv_device(). It results in
kernel crash as observed.

This fixes the issue by passing @rmv_data, not its address to
eeh_rmv_device() in eeh_reset_device().

Fixes: 67086e32b564 ("powerpc/eeh: powerpc/eeh: Support error recovery for VF PE")
Reported-by: Pridhiviraj Paidipeddi 
Signed-off-by: Gavin Shan 
Signed-off-by: Michael Ellerman

powerpc/eeh: Fix invalid cached PE primary bus

2016-06-17T09:51:47+00:00

The PE primary bus cannot be got from its child devices when having
full hotplug in error recovery. The PE primary bus is cached, which
is done in commit <05ba75f84864> ("powerpc/eeh: Fix stale cached primary
bus"). In eeh_reset_device(), the flag (EEH_PE_PRI_BUS) is cleared
before the PCI hot remove. eeh_pe_bus_get() then returns NULL as the
PE primary bus in pnv_eeh_reset() and it crashes the kernel eventually.

This fixes the issue by clearing the flag (EEH_PE_PRI_BUS) before the
PCI hot add. With it, the PowerNV EEH reset backend (pnv_eeh_reset())
can get valid PE primary bus through eeh_pe_bus_get().

Fixes: 67086e32b564 ("powerpc/eeh: powerpc/eeh: Support error recovery for VF PE")
Reported-by: Pridhiviraj Paidipeddi 
Signed-off-by: Gavin Shan 
Signed-off-by: Michael Ellerman

powerpc/eeh: Ignore handlers in eeh_pe_reset_and_recover()

2016-05-12T09:52:20+00:00

The function eeh_pe_reset_and_recover() is used to recover EEH
error when the passthrough device are transferred to guest and
backwards, meaning the device's driver is vfio-pci or none. In
both cases, the handlers triggered by eeh_report_reset() and
eeh_report_resume() shouldn't be called.

This ignores the error handlers from eeh_report_reset() and
eeh_report_resume().

Signed-off-by: Gavin Shan 
Reviewed-by: Russell Currey 
Signed-off-by: Michael Ellerman

powerpc/eeh: Restore initial state in eeh_pe_reset_and_recover()

2016-05-12T09:52:20+00:00

The function eeh_pe_reset_and_recover() is used to recover EEH
error when the passthrou device are transferred to guest and
backwards. The content in the device's config space will be lost
on PE reset issued in the middle of the recovery. The function
saves/restores it before/after the reset. However, config access
to some adapters like Broadcom BCM5719 at this point will causes
fenced PHB. The config space is always blocked and we save 0xFF's
that are restored at late point. The memory BARs are totally
corrupted, causing another EEH error upon access to one of the
memory BARs.

This restores the config space on those adapters like BCM5719
from the content saved to the EEH device when it's populated,
to resolve above issue.

Fixes: 5cfb20b9 ("powerpc/eeh: Emulate EEH recovery for VFIO devices")
Cc: stable@vger.kernel.org #v3.18+
Signed-off-by: Gavin Shan 
Reviewed-by: Russell Currey 
Signed-off-by: Michael Ellerman

powerpc/eeh: Don't report error in eeh_pe_reset_and_recover()

2016-05-12T09:52:20+00:00

The function eeh_pe_reset_and_recover() is used to recover EEH
error when the passthrough device are transferred to guest and
backwards, meaning the device's driver is vfio-pci or none.
When the driver is vfio-pci that provides error_detected() error
handler only, the handler simply stops the guest and it's not
expected behaviour. On the other hand, no error handlers will
be called if we don't have a bound driver.

This ignores the error handler in eeh_pe_reset_and_recover()
that reports the error to device driver to avoid the exceptional
behaviour.

Fixes: 5cfb20b9 ("powerpc/eeh: Emulate EEH recovery for VFIO devices")
Cc: stable@vger.kernel.org #v3.18+
Signed-off-by: Gavin Shan 
Reviewed-by: Russell Currey 
Signed-off-by: Michael Ellerman

powerpc/pci: Rename pcibios_{add, remove}_pci_devices()

2016-05-11T11:54:23+00:00

This renames pcibios_{add,remove}_pci_devices() to avoid conflicts
with names of the weak functions in PCI subsystem, which have the
prefix "pcibios". No logical changes introduced.

Signed-off-by: Gavin Shan 
Reviewed-By: Alistair Popple 
Reviewed-by: Andrew Donnellan 
Reviewed-by: Alexey Kardashevskiy 
Signed-off-by: Michael Ellerman

powerpc/eeh: Don't remove passed VFs

2016-03-08T22:58:27+00:00

When we have partial hotplug as part of the error recovery on PF,
the VFs that are bound with vfio-pci driver will experience hotplug.
That's not allowed.

This checks if the VF PE is passed or not. If it does, we leave
the VF without removing it.

Signed-off-by: Gavin Shan 
Reviewed-by: Russell Currey 
Signed-off-by: Michael Ellerman

powerpc/eeh: Don't propagate error to guest

2016-03-08T22:58:25+00:00

When EEH error happened to the parent PE of those PEs that have
been passed through to guest, the error is propagated to guest
domain and the VFIO driver's error handlers are called. It's not
correct as the error in the host domain shouldn't be propagated
to guests and affect them.

This adds one more limitation when calling EEH error handlers.
If the PE has been passed through to guest, the error handlers
won't be called.

Signed-off-by: Gavin Shan 
Reviewed-by: Russell Currey 
Signed-off-by: Michael Ellerman

powerpc/eeh: powerpc/eeh: Support error recovery for VF PE

2016-03-08T22:58:23+00:00

PFs are enumerated on PCI bus, while VFs are created by PF's driver.

In EEH recovery, it has two cases:
1. Device and driver is EEH aware, error handlers are called.
2. Device and driver is not EEH aware, un-plug the device and plug it again
by enumerating it.

The special thing happens on the second case. For a PF, we could use the
original pci core to enumerate the bus, while for VF we need to record the
VFs which aer un-plugged then plug it again.

Also The patch caches the VF index in pci_dn, which can be used to
calculate VF's bus, device and function number. Those information helps to
locate the VF's PCI device instance when doing hotplug during EEH recovery
if necessary.

Signed-off-by: Wei Yang 
Acked-by: Gavin Shan 
Signed-off-by: Michael Ellerman

Merge tag 'powerpc-4.5-4' into next

2016-02-25T10:52:58+00:00

Pull in our current fixes from 4.5, in particular the "Fix Multi hit
ERAT" bug is causing folks some grief when testing next.