commit ad67b437f187ea818b2860524d10f878fadfdd99 upstream.

b84106b4e229 ("PCI: Disable IO/MEM decoding for devices with non-compliant
BARs") disabled BAR sizing for BARs 0-5 of devices that don't comply with
the PCI spec.  But it didn't do anything for expansion ROM BARs, so we
still try to size them, resulting in warnings like this on Broadwell-EP:

  pci 0000:ff:12.0: BAR 6: failed to assign [mem size 0x00000001 pref]

Move the non-compliant BAR check from __pci_read_base() up to
pci_read_bases() so it applies to the expansion ROM BAR as well as
to BARs 0-5.

Note that direct callers of __pci_read_base(), like sriov_init(), will now
bypass this check.  We haven't had reports of devices with broken SR-IOV
BARs yet.

[bhelgaas: changelog]
Fixes: b84106b4e229 ("PCI: Disable IO/MEM decoding for devices with non-compliant BARs")
Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Ingo Molnar <mingo@redhat.com>
CC: "H. Peter Anvin" <hpa@zytor.com>
CC: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Pull PCI fixes from Bjorn Helgaas:
 "Since v4.5, we've WARNed during resume if a PCI device, including a
  Thunderbolt device, was added while we were suspended.  A change we
  merged for v4.6-rc1 turned that warning into a system hang.  These
  enumeration patches from Lukas Wunner fix this issue:

   - Fix BUG on device attach failure
   - Do not treat EPROBE_DEFER as device attach failure"

* tag 'pci-v4.6-fixes-3' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
  PCI: Do not treat EPROBE_DEFER as device attach failure
  PCI: Fix BUG on device attach failure

Linux 4.5 introduced a behavioral change in device probing during the
suspend process with commit 013c074f8642 ("PM / sleep: prohibit devices
probing during suspend/hibernation"): It defers device probing during the
entire suspend process, starting from the prepare phase and ending with the
complete phase.  A rule existed before that "we rely on subsystems not to
do any probing once a device is suspended" but it is enforced only now
(Alan Stern, https://lkml.org/lkml/2015/9/15/908).

This resulted in a WARN splat if a PCI device (e.g., Thunderbolt) is
plugged in while the system is asleep: Upon waking up, pciehp_resume()
discovers new devices in the resume phase and immediately tries to bind
them to a driver.  Since probing is now deferred, device_attach() returns
-EPROBE_DEFER, which provoked a WARN in pci_bus_add_device().

Linux 4.6-rc1 aggravates the situation with commit ab1a187bba5c ("PCI:
Check device_attach() return value always"): If device_attach() returns a
negative value, pci_bus_add_device() now removes the sysfs and procfs
entries for the device and pci_bus_add_devices() subsequently locks up with
a BUG.  Even with the BUG fixed we're still in trouble because the device
remains on the deferred probing list even though its sysfs and procfs
entries are gone and its children won't be added.

Fix by not interpreting -EPROBE_DEFER as failure.  The device will be
probed eventually (through device_unblock_probing() in dpm_complete()) and
there is proper locking in place to avoid races (e.g., if devices are
unplugged again und thus deleted from the system before deferred probing
happens, I have tested this).  Also, those functions which dereference
dev->driver (e.g. pci_pm_*()) do contain proper NULL pointer checks.  So it
seems safe to ignore -EPROBE_DEFER.

Fixes: ab1a187bba5c ("PCI: Check device_attach() return value always")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Grygorii Strashko <grygorii.strashko@ti.com>
Cc: Alan Stern <stern@rowland.harvard.edu>

Previously when pci_bus_add_device() called device_attach() and it returned
a negative value, we emitted a WARN but carried on.

Commit ab1a187bba5c ("PCI: Check device_attach() return value always"),
introduced in Linux 4.6-rc1, changed this to unwind all steps preceding
device_attach() and to not set dev->is_added = 1.

The latter leads to a BUG if pci_bus_add_device() was called from
pci_bus_add_devices().  Fix by not recursing to a child bus if
device_attach() failed for the bridge leading to it.

This can be triggered by plugging in a PCI device (e.g. Thunderbolt) while
the system is asleep.  The system locks up when woken because
device_attach() returns -EPROBE_DEFER.

Fixes: ab1a187bba5c ("PCI: Check device_attach() return value always")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Pull PCI fixes from Bjorn Helgaas:
 "These are fixes for two issues:

   - The VPD parsing code we added for v4.6 keeps some devices from
     crashing, but also keeps cxgb4 from reading non-standard extra VPD
     data that is relies on.  Hariprasad added a way for the driver to
     specify how much VPD is valid.

   - The i.MX6 active-low reset GPIO support we added in v4.5 caused
     regressions on some boards, so we're reverting that.

  VPD:
    Add pci_set_vpd_size() (Hariprasad Shenai)
    cxgb4: Set VPD size so we can read both VPD structures (Hariprasad Shenai)

  Freescale i.MX6 host bridge driver:
    Revert "PCI: imx6: Add support for active-low reset GPIO" (Fabio Estevam)"

* tag 'pci-v4.6-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
  cxgb4: Set VPD size so we can read both VPD structures
  PCI: Add pci_set_vpd_size() to set VPD size
  Revert "PCI: imx6: Add support for active-low reset GPIO"

After 104daa71b396 ("PCI: Determine actual VPD size on first access"), the
PCI core computes the valid VPD size by parsing the VPD starting at offset
0x0.  We don't attempt to read past that valid size because that causes
some devices to crash.

However, some devices do have data past that valid size.  For example,
Chelsio adapters contain two VPD structures, and the driver needs both of
them.

Add pci_set_vpd_size().  If a driver knows it is safe to read past the end
of the VPD data structure at offset 0, it can use pci_set_vpd_size() to
allow access to as much data as it needs.

[bhelgaas: changelog, split patches, rename to pci_set_vpd_size() and
return int (not ssize_t)]
Fixes: 104daa71b396 ("PCI: Determine actual VPD size on first access")
Tested-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Casey Leedom <leedom@chelsio.com>
Signed-off-by: Hariprasad Shenai <hariprasad@chelsio.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

The PCI config access checked the file capabilities correctly, but used
the itnernal security capability check rather than the helper function
that is actually meant for that.

The security_capable() has unusual return values and is not meant to be
used elsewhere (the only other use is in the capability checking
functions that we actually intend people to use, and this odd PCI usage
really stood out when looking around the capability code.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Commit 5c5fb40de8f1 ("PCI: imx6: Add support for active-low reset GPIO")
cause regressions on some boards like MX6 Gateworks Ventana, for example.

The reason for the breakage is that this commit sets the GPIO polarity in
the wrong logic level.

Also, the commit log is wrong because active-low reset GPIO is what the
driver used to support since the beginning.

So keep the old behavior that ignores the GPIO polarity specified in the
device tree and treat the PCI reset GPIO as active-low.

Reported-by: Krzysztof Hałasa <khalasa@piap.pl>
Tested-by: Tim Harvey <tharvey@gateworks.com>	# Gateworks Ventana
Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Tim Harvey <tharvey@gateworks.com>
Acked-by: Lucas Stach <l.stach@pengutronix.de>
CC: stable@vger.kernel.org	# v4.5+

Revert 5c3b99d05752 ("PCI: dra7xx: Mark driver as broken").

1c96bee4df19 ("ARM: DRA7: hwmod: Add custom reset handler for PCIeSS")
added support to de-assert PCIe reset, so DRA7x PCIe is not broken anymore.

Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

Commit e7e127e3c767 ("PCI: Include pci/hotplug Kconfig directly from
pci/Kconfig") added one line to pci/Kconfig.  However, for some mysterious
reason it isn't there now, even though there are no traces of removing it
in the git log.

I detected this issue when 'make oldconfig' removed all the options that
depended on HOTPLUG_PCI.

[bhelgaas: I botched the cfeb8139a1fb ("Merge branch 'pci/host-hv' into
next") merge.  "git diff cfeb8139a1fb^ cfeb8139a1fb" shows a conflict in
drivers/pci/Kconfig, and I mistakenly dropped the hotplug/Kconfig piece.]
Signed-off-by: Tero Roponen <tero.roponen@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>