linux-stable.git/drivers/pci/hotplug, branch linux-2.6.25.y

pciehp: don't enable slot unless forced

2008-03-18T02:26:05+00:00

This fixes a 2.6.25 regression reported by Alex Chiang.

Invoke pciehp_enable_slot() at startup only when pciehp_force=1.
Some HP equipment apparently cannot cope with it otherwise.

This restores the (previously working) 2.6.24 behaviour here,
while allowing machines that need a kick to use pciehp_force=1.

This was the original design back in October 2007,
but Kristen suggested we try without it first:

   Kristen Carlson Accardi wrote:
   >I think it would be ok to try allowing the slot to be enabled when not
   >using pciehp_force mode.  We can wrap it later if it proves to break things

This ended up breaking one of Alex's setups,
so it's time to put the wrapper back in now.

Signed-off-by: Mark Lord 
Acked-by: Alex Chiang 
Acked-by: Kristen Carlson Accardi 
Signed-off-by: Linus Torvalds

PCI Hotplug: Fix small mem leak in IBM Hot Plug Controller Driver

2008-03-10T23:38:02+00:00

In drivers/pci/hotplug/ibmphp_ebda.c::ebda_rsrc_controller(), storage is
allocated with kzalloc() and assigned to 'tmp_slot'.  Then lots of
stuff, like ->flag, ->supported_speed etc is set in tmp_slot.  A bit
further down there's then this test :

  if (!bus_info_ptr1) {
    rc = -ENODEV;
    goto error;
  }

At this point, tmp_slot has not been assigned to anything, so when
erroring-out we want to free it, but nothing at the 'error:' label
free's 'tmp_slot' - and we can't really free 'tmp_slot' at 'error:'
since we may jump to that label later when 'tmp_slot' *has* been used
and we do not want it freed. So, the only sane option left seems to be
to kfree(tmp_slot) just before jumping to the 'error:' label in the one
place where this is what actually makes sense. The following patch does
just that and thus kills off a tiny potential memory leak.


Signed-off-by: Jesper Juhl 
Signed-off-by: Greg Kroah-Hartman

pci: hotplug: pciehp: fix error code path in hpc_power_off_slot

2008-03-04T23:07:04+00:00

Fix the error code path in hpc_power_off_slot().

The Bad DLLP Mask bit must be restored before return.

Signed-off-by: Kenji Kaneshige 
Signed-off-by: Kristen Carlson Accardi 
Signed-off-by: Greg Kroah-Hartman

PCI: fix section mismatch warning in pci_scan_child_bus

2008-03-04T23:07:03+00:00

Fix following warning:
WARNING: vmlinux.o(.text+0x47bdb1): Section mismatch in reference from the function pci_scan_child_bus() to the function .devinit.text:pcibios_fixup_bus()

We had plenty of functions that could be annotated __devinit but due to
the former restriction that exported symbols could not be annotated
they were not so.  So annotate these function and fix the references
from the pci/hotplug/* code to silence the resuting warnings.

Signed-off-by: Sam Ravnborg 
Signed-off-by: Greg Kroah-Hartman

PCI: don't load acpi_php when acpi is disabled

2008-02-21T23:34:37+00:00

When acpi=off and pci=nomsi, don't load acpiphp.

Fixes this:

pci_hotplug: PCI Hot Plug PCI Core version: 0.5
acpiphp: ACPI Hot Plug PCI Controller Driver version: 0.5
ACPI Exception (utmutex-0263): AE_BAD_PARAMETER, Thread
FFFF81103CC54000 could not acquire Mutex [1] [20070126]

[akpm@linux-foundation.org: export acpi_pci_disabled for acpiphp.ko]
[akpm@linux-foundation.org: fix return statement]
Signed-off-by: Yinghai Lu 
Cc: Kristen Carlson Accardi 
Signed-off-by: Andrew Morton 
Signed-off-by: Greg Kroah-Hartman

PCI: hotplug: acpiphp_ibm: Remove get device information

2008-02-21T23:34:35+00:00

drivers/pci/hotplug/acpiphp_ibm.c:ibm_find_acpi_device() is not
large enough to accommodate data returned by the _CID method
executed from acpi_get_object_info().

This patch eliminates the problem by letting ACPI code
(instead of driver code) determine and obtain a correctly
sized buffer.

Signed-off-by: Gary Hade 
Signed-off-by: Kristen Carlson Accardi 
Signed-off-by: Greg Kroah-Hartman

PCI: Fix fakephp deadlock

2008-02-01T23:04:30+00:00

If the fakephp driver is used to emulate removal of a PCI device by
writing text string "0" to the "power" sysfs attribute file, this causes
its parent directory and its contents (including the "power" file) to be
deleted before the write operation returns.  Unfortunately, it ends up
in a deadlock waiting for itself to complete.

The deadlock is as follows: sysfs_write_file calls flush_write_buffer
which calls sysfs_get_active_two before calling power_write_file in
pci_hotplug_core.c via the sysfs store operation. The power_write_file
function calls disable_slot in fakephp.c via the slot operation.  The
disable_slot function calls remove_slot which calls pci_hp_deregister
(back in pci_hotplug_core.c) which calls fs_remove_slot which calls
sysfs_remove_file to remove the "power" file. The sysfs_remove_file
function calls sysfs_hash_and_remove which calls sysfs_addrm_finish
which calls sysfs_deactivate. The sysfs_deactivate function sees that
something has an active reference on the sysfs_dirent (from the
previous call to sysfs_get_active_two back up the call stack somewhere)
so waits for the active reference to go away, which is of course
impossible.

The problem has been present since 2.6.21.

This patch breaks the deadlock by queuing work queue items on a single-
threaded work queue to remove a slot from sysfs, and to rescan the PCI
buses.  There is also some protection against disabling a slot that is
already being removed.

Signed-off-by: Ian Abbott 
Cc: Kristen Accardi 
Signed-off-by: Greg Kroah-Hartman

pciehp: block new requests from the device before power off

2008-02-01T23:04:28+00:00

Disable Bus Master, SERR# and INTx to ensure that no new Requests will
be generated from the device before turning power off, in accordance
with the specification.

Signed-off-by: Kenji Kaneshige 
Signed-off-by: Kristen Carlson Accardi 
Signed-off-by: Greg Kroah-Hartman

pciehp: workaround against Bad DLLP during power off

2008-02-01T23:04:28+00:00

Set Bad DLLP Mask bit in Correctable Error Mask Register during
turning power off the slot.

This is the workaround against Bad DLLP error that sometimes happen
during turning power off on the slot which conforms to PCI Express
1.0a spec. The cause of this error seems that PCI Express 1.0a spec
doesn't have the following consideration that was added to PCI Express
1.1 spec.

    "If the port is associated with a hot-pluggable slot (Hot-Plug
    Capable bit in the Slot Capabilities register set to 1b), and
    Power Controller Control bit in Slot Control register is 1b(Off),
    then any transition to DL Inactive must not be considered an
    error."

Signed-off-by: Kenji Kaneshige 
Signed-off-by: Kristen Carlson Accardi 
Signed-off-by: Greg Kroah-Hartman

pciehp: wait for 1000ms before LED operation after power off

2008-02-01T23:04:28+00:00

After turning power off, we must wait for at least 1 second *before*
LED operation.

Signed-off-by: Kenji Kaneshige 
Signed-off-by: Kristen Carlson Accardi 
Signed-off-by: Greg Kroah-Hartman