linux.git/arch/powerpc/kernel/pci_dn.c, branch v5.4.211

powerpc/sriov: Remove VF eeh_dev state when disabling SR-IOV

2020-02-24T07:36:56+00:00

[ Upstream commit 1fb4124ca9d456656a324f1ee29b7bf942f59ac8 ]

When disabling virtual functions on an SR-IOV adapter we currently do not
correctly remove the EEH state for the now-dead virtual functions. When
removing the pci_dn that was created for the VF when SR-IOV was enabled
we free the corresponding eeh_dev without removing it from the child device
list of the eeh_pe that contained it. This can result in crashes due to the
use-after-free.

Signed-off-by: Oliver O'Halloran 
Reviewed-by: Sam Bobroff 
Tested-by: Sam Bobroff 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20190821062655.19735-1-oohall@gmail.com
Signed-off-by: Sasha Levin

powerpc/eeh: Fix race when freeing PDNs

2019-09-05T04:22:37+00:00

When hot-adding devices we rely on the hotplug driver to create pci_dn's
for the devices under the hotplug slot. Converse, when hot-removing the
driver will remove the pci_dn's that it created. This is a problem because
the pci_dev is still live until it's refcount drops to zero. This can
happen if the driver is slow to tear down it's internal state. Ideally, the
driver would not attempt to perform any config accesses to the device once
it's been marked as removed, but sometimes it happens. As a result, we
might attempt to access the pci_dn for a device that has been torn down and
the kernel may crash as a result.

To fix this, don't free the pci_dn unless the corresponding pci_dev has
been released.  If the pci_dev is still live, then we mark the pci_dn with
a flag that indicates the pci_dev's release function should free it.

Signed-off-by: Oliver O'Halloran 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20190903101605.2890-3-oohall@gmail.com

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156

2019-05-30T18:26:35+00:00

Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version this program is distributed in the
  hope that it will be useful but without any warranty without even
  the implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details you
  should have received a copy of the gnu general public license along
  with this program if not write to the free software foundation inc
  59 temple place suite 330 boston ma 02111 1307 usa

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1334 file(s).

Signed-off-by: Thomas Gleixner 
Reviewed-by: Allison Randal 
Reviewed-by: Richard Fontana 
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de
Signed-off-by: Greg Kroah-Hartman

powerpc/pci: Separate SR-IOV Calls

2017-12-11T02:03:35+00:00

SR-IOV can now be enabled for the powernv platform and pseries
platform. Therefore move the appropriate calls to machine dependent
code instead of relying on definition at compile time.

Signed-off-by: Bryant G. Ly 
Signed-off-by: Juan J. Alvarez 
Acked-by: Russell Currey 
Reviewed-by: Alexey Kardashevskiy 
Signed-off-by: Michael Ellerman

powerpc/pci: Remove OF node back pointer from pci_dn

2017-08-31T04:26:12+00:00

The check_req() helper uses pci_get_pdn() to get an OF node pointer.
pci_get_pdn() returns a pci_dn pointer which either:
1) from the OF node returned by pci_device_to_OF_node();
2) from the parent child_list where entries don't have OF node pointers.
Since check_req() does not care about 2), it can call
pci_device_to_OF_node() directly, hence the change.

The find_pe_dn() helper uses embedded pci_dn to get an OF node which is
also stored in edev->pdev so let's take a shortcut and call
pci_device_to_OF_node() directly.

With these 2 changes, we can finally get rid of the OF node back pointer.

Signed-off-by: Alexey Kardashevskiy 
Signed-off-by: Michael Ellerman

powerpc/eeh: Reduce use of pci_dn::node

2017-08-31T04:26:10+00:00

The pci_dn struct caches a OF device node pointer in order to access
the "ibm,loc-code" property when EEH is recovering.

However, when this happens in eeh_dev_check_failure(), we also have
a pci_dev pointer which should have a valid pointer to the device node
when pci_dn has one (both pointers are not NULL for physical functions
and are NULL for virtual functions).

This changes pci_remove_device_node_info() to look for a parent of
the node being removed, just like pci_add_device_node_info() does when it
references the parent node.

This is the first step to get rid of pci_dn::node.

Signed-off-by: Alexey Kardashevskiy 
Signed-off-by: Michael Ellerman

powerpc/pci: Remove unused parameter from add_one_dev_pci_data()

2017-08-31T04:26:07+00:00

pdev is always NULL, remove it.

To make checkpatch.pl happy, this also removes the "out of memory"
message.

Signed-off-by: Alexey Kardashevskiy 
Reviewed-by: Andrew Donnellan 
Acked-by: Russell Currey 
Signed-off-by: Michael Ellerman

powerpc/pci: Fix build with PCI_IOV=y and EEH=n

2016-07-07T06:33:27+00:00

Despite attempting to fix this in commit fb36e9073693 ("powerpc/pci: Fix
SRIOV not building without EEH enabled"), the build is still broken when
PCI_IOV=y and EEH=n (eg. g5_defconfig with PCI_IOV=y):

  arch/powerpc/kernel/pci_dn.c: In function ‘remove_dev_pci_data’:
  arch/powerpc/kernel/pci_dn.c:230:18: error: unused variable ‘edev’

Incorporate Ben's idea of using __maybe_unused to avoid so many #ifdefs.

Signed-off-by: Michael Ellerman

powerpc/pci: Delay populating pdn

2016-06-21T05:30:56+00:00

The pdn (struct pci_dn) instances are allocated from memblock or
bootmem when creating PCI controller (hoses) in setup_arch(). PCI
hotplug, which will be supported by proceeding patches, releases
PCI device nodes and their corresponding pdn on unplugging event.
The memory chunks for pdn instances allocated from memblock or
bootmem are hard to reused after being released.

This delays creating pdn by pci_devs_phb_init() from setup_arch()
to core_initcall() so that they are allocated from slab. The memory
consumed by pdn can be released to system without problem during
PCI unplugging time. It indicates that pci_dn is unavailable in
setup_arch() and the the fixup on pdn (like AGP's) can't be carried
out that time. We have to do that in pcibios_root_bridge_prepare()
on maple/pasemi/powermac platforms where/when the pdn is available.
pcibios_root_bridge_prepare is called from subsys_initcall() which
is executed after core_initcall() so the code flow does not change.

At the mean while, the EEH device is created when pdn is populated,
meaning pdn and EEH device have same life cycle. In turn, we needn't
call eeh_dev_init() to create EEH device explicitly.

Signed-off-by: Gavin Shan 
Reviewed-by: Alexey Kardashevskiy 
Signed-off-by: Michael Ellerman

powerpc/pci: Fix SRIOV not building without EEH enabled

2016-06-17T06:52:22+00:00

On Book3E CPUs (and possibly other configs), it is possible to have SRIOV
(CONFIG_PCI_IOV) set without CONFIG_EEH.  The SRIOV code does not check
for this, and if EEH is disabled, pci_dn.c fails to build.

Fix this by gating the EEH-specific code in the SRIOV implementation
behind CONFIG_EEH.

Fixes: 39218cd0 ("powerpc/eeh: EEH device for VF")
Reported-by: Michael Ellerman 
Signed-off-by: Russell Currey 
Signed-off-by: Michael Ellerman