e24dcbef93 ("shpchp: update workqueue usage") was described as adding
non-ordered shpchp_wq, but it actually made it an *ordered* workqueue.
This patch changes shpchp_wq to be non-ordered, as described in the
e24dcbef93 commit log and as was done for pciehp by a827ea307b ("pciehp:
update workqueue usage").
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Tejun Heo <tj@kernel.org>
When we have a hotplug-capable PCIe port with a second hotplug-capable
PCIe port below it, removing the device below the upstream port causes
a deadlock.
The deadlock happens because we use the pciehp_wq workqueue to run
pciehp_power_thread(), which uses pciehp_disable_slot() to remove devices
below the upstream port. When we remove the downstream PCIe port, we call
pciehp_remove(), the pciehp driver's .remove() method. That calls
flush_workqueue(pciehp_wq), which deadlocks because the
pciehp_power_thread() work item is still running.
This patch avoids the deadlock by creating a workqueue for every PCIe port
and removing the single shared workqueue.
Here's the call path that leads to the deadlock:
pciehp_queue_pushbutton_work
queue_work(pciehp_wq) # queue pciehp_power_thread
...
pciehp_power_thread
pciehp_disable_slot
remove_board
pciehp_unconfigure_device
pci_stop_and_remove_bus_device
...
pciehp_remove # pciehp driver .remove method
pciehp_release_ctrl
pcie_cleanup_slot
flush_workqueue(pciehp_wq)
This is fairly urgent because it can be caused by simply unplugging a
Thunderbolt adapter, as reported by Daniel below.
[bhelgaas: changelog]
Reference: http://lkml.kernel.org/r/CAMVG2ssiRgcTD1bej2tkUUfsWmpL5eNtPcNif9va2-Gzb2u8nQ@mail.gmail.com
Reported-and-tested-by: Daniel J Blueman <daniel@quora.org>
Reviewed-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: stable@vger.kernel.org
The callers of acpi_bus_add() usually assume that if it has
succeeded, then a struct acpi_device object has been attached to
the handle passed as the first argument. Unfortunately, however,
this assumption is wrong, because acpi_bus_scan(), and acpi_bus_add()
too as a result, may return a pointer to a different struct
acpi_device object on success (it may be an object corresponding to
one of the descendant ACPI nodes in the namespace scope below that
handle).
For this reason, the callers of acpi_bus_add() who care about
whether or not a struct acpi_device object has been created for
its first argument need to check that using acpi_bus_get_device()
anyway, so the second argument of acpi_bus_add() is not really
useful for them. The same observation applies to acpi_bus_scan()
executed directly from acpi_scan_init().
Therefore modify the relevant callers of acpi_bus_add() to check the
existence of the struct acpi_device in question with the help of
acpi_bus_get_device() and drop the no longer necessary second
argument of acpi_bus_add(). Accordingly, modify acpi_scan_init() to
use acpi_bus_get_device() to get acpi_root and drop the no longer
needed second argument of acpi_bus_scan().
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Toshi Kani <toshi.kani@hp.com>
Notice that acpi_bus_add() uses only 2 of its 4 arguments and
redefine its header to match the body. Update all of its callers as
necessary and observe that this leads to quite a number of removed
lines of code (Linus will like that).
Add a kerneldoc comment documenting acpi_bus_add() and wonder how
its callers make wrong assumptions about the second argument (make
note to self to take care of that later).
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Toshi Kani <toshi.kani@hp.com>
The ACPI PCI root bridge driver was the only ACPI driver implementing
the .start() callback, which isn't used by any ACPI drivers any more
now.
For this reason, acpi_start_single_object() has no purpose any more,
so remove it and all references to it. Also remove
acpi_bus_start_device(), whose only purpose was to call
acpi_start_single_object().
Moreover, since after the removal of acpi_bus_start_device() the
only purpose of acpi_bus_start() remains to call
acpi_update_all_gpes(), move that into acpi_bus_add() and drop
acpi_bus_start() too, remove its header from acpi_bus.h and
update all of its former users accordingly.
This change was previously proposed in a different from by
Yinghai Lu.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Toshi Kani <toshi.kani@hp.com>
Add SCLP PCI configure/deconfigure and implement a PCI hotplug
controller (s390_pci_hpc). The hotplug controller creates a slot
for every PCI function in stand-by or configured state. The PCI
functions are named after the PCI function ID (fid). By writing to
the power attribute in /sys/bus/pci/slots/<fid>/power the PCI function
is moved to stand-by or configured state. If moved to the configured
state the device is automatically scanned by the s390 PCI layer.
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
CONFIG_HOTPLUG is going away as an option so __devexit_p, __devint,
__devinitdata, __devinitconst, and _devexit are no longer needed.
Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 0d52f54e2e (PCI / ACPI: Make acpiphp
ignore root bridges using PCIe native hotplug) added code that made the
acpiphp driver completely ignore PCIe root complexes for which the kernel
had been granted control of the native PCIe hotplug feature by the BIOS
through _OSC. Later commit 619a5182d1
"PCI hotplug: Always allow acpiphp to handle non-PCIe bridges" relaxed
the constraints to allow acpiphp driver handle non-PCIe bridges under
such a complex. The constraint needs to be relaxed further to allow
acpiphp driver to handle PCIe ports without native PCIe hotplug capability.
Some MR-IOV switch chipsets, such PLX8696, support multiple virtual PCIe
switches and may migrate downstream ports among virtual switches. To
migrate a downstream port from the source virtual switch to the target, the
port needs to be hot-removed from the source and hot-added into the target.
The pciehp driver can't be used here because there are no slots within the
virtual PCIe switch. So acpiphp driver is used to support downstream port
migration. A typical configuration is as below:
[Root without native PCIe HP]
[Upstream port of vswitch without native PCIe HP]
[Downstream port of vswitch with native PCIe HP]
[PCIe endpoint]
Here acpiphp driver will be used to handle root ports and upstream port
in the virtual switch, and pciehp driver will be used to handle downstream
ports in the virtual switch.
Signed-off-by: Jiang Liu <liuj97@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
This patch changes .add/.remove interfaces of acpi_pci_driver.
In the current implementation acpi_handle is passed as a parameter
of .add/.remove interface. However, the acpi_pci_root structure
contains more useful information than just the acpi_handle. This
enables us to avoid some useless lookups in each acpi_pci_driver.
Note: This changes interfaces used by acpi_pci_register_driver(), an
exported symbol. This patch updates all the in-kernel users, but any
out-of-kernel acpi_pci_register_driver() users will need updates.
[bhelgaas: changelog]
Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Function eeh_rmv_from_parent_pe() could be called by the path of
either normal PCI hotplug, or EEH recovery. For the former case,
we need purge the corresponding PE on removal of the associated
PE bus.
The patch tries to cover that by passing more information to function
pcibios_remove_pci_devices() so that we know if the corresponding PE
needs to be purged or be marked as "invalid".
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Following code has a race window between pci_find_bus() and pci_get_slot()
if PCI hotplug operation happens between them which removes the pci_bus.
So use PCI hotplug safe interface pci_get_domain_bus_and_slot() instead,
which also reduces code complexity.
struct pci_bus *pci_bus = pci_find_bus(domain, busno);
struct pci_dev *pci_dev = pci_get_slot(pci_bus, devfn);
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
register & 0x0B == 0x04 is never true, the code will always take the
(identical) 0x00 path anyway. Remove the dead code paths.
Resolves-bug: https://bugzilla.kernel.org/show_bug.cgi?id=44151
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Previously, the driver ignored resume unless the pciehp_force module_param
was specified. On some laptops that means that interrupts are not
delivered after S3, so card removals and insertions are not handled.
This patch makes the driver handle resume regardless of pciehp_force.
[bhelgaas: changelog]
Signed-off-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rjw@sisk.pl>
The fakephp driver was scheduled for removal in 2011.
Fakephp presented /sys/bus/pci/slots/.../power files for every PCI
function. Writing "0" to one of these files logically removed the device
from the system. The PCI core now provides the same functionality with
/sys/bus/pci/devices/.../remove.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
This removes unused code that was already commented out.
Tested-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Use pci_stop_and_remove_bus_device() like most other hotplug drivers
rather than stopping and removing separately.
Tested-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
acpiphp_disable_slot() turns off power to the slot immediately after
calling disable_device(), so there's no point in disabling any bridges
below the slot: we're about to turn them off anyway.
Tested-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Typically, the return value desired for the failure of a function with an
integer return value is a negative integer. In these cases, the return
value is sometimes a negative integer and sometimes 0, due to a subsequent
initialization of the return variable within the loop.
A simplified version of the semantic match that finds this problem is:
(http://coccinelle.lip6.fr/)
//<smpl>
@r exists@
identifier ret;
position p;
constant C;
expression e1,e3,e4;
statement S;
@@
ret = -C
... when != ret = e3
when any
if@p (...) S
... when any
if (\(ret != 0\|ret < 0\|ret > 0\) || ...) { ... return ...; }
... when != ret = e3
when any
*if@p (...)
{
... when != ret = e4
return ret;
}
//</smpl>
[bhelgaas: squashed into one patch]
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Should not have two, just remove debug, and use module_param_named
instead.
Also change acpiphp_debug to bool.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Check whether we evaluated _ADR successfully. Previously we ignored
failure, so we would have used garbage data from the stack as the device
and function number.
We return AE_OK so that we ignore only this slot and continue looking
for other slots.
Found by Coverity (CID 113981).
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
"slots_not_empty" is initialized to zero and can't be set again before
reaching this point, so this return statement is dead. Remove it.
Found by Coverity (CID 114324).
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
When we add a device with acpiphp, we enumerate all functions in the
slot with pci_scan_slot(), regardless of whether they have associated
ACPI methods such as _EJ0.
When removing the device, we previously removed only the functions
with those ACPI methods. This patch makes the remove symmetric with the
add: we remove all functions in the slot, whether they have associated
ACPI methods or not.
With qemu-kvm and SeaBIOS, we can build a multi-function device where
only function 0 has _EJ0 and _ADR (see bugzilla below). Removing and
re-adding that slot (including all functions of the device) works correctly
with Windows guests. This patch makes it also work in Linux guests.
[bhelgaas: restructure loop iteration, pull out of slot->funcs loop]
Reference: https://bugzilla.kernel.org/show_bug.cgi?id=43219
Signed-off-by: Amos Kong <kongjianjun@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Previously, we acquired two references to function 0, but only released
one.
[bhelgaas: split this out from "remove all functions" fix]
Signed-off-by: Amos Kong <kongjianjun@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Use the new generic pci_hp_add_bridge() interface.
[bhelgaas: changelog]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Use the new generic pci_hp_add_bridge() interface.
[bhelgaas: changelog]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Use the new generic pci_hp_add_bridge() interface.
[bhelgaas: changelog]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Use the new generic pci_hp_add_bridge() interface.
[bhelgaas: changelog]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Use the new generic pci_hp_add_bridge() interface.
[bhelgaas: changelog]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Use the new generic pci_hp_add_bridge() interface.
[bhelgaas: split "add generic pci_hp_add_bridge()" into a separate patch]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Replace the struct pci_bus secondary/subordinate members with the
struct resource busn_res. Later we'll build a resource tree of these
bus numbers.
[bhelgaas: changelog]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
pci_stop_bus_device gets called before in the same loop.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
The old pci_remove_bus_device actually did stop and remove.
Make the name reflect that to reduce confusion.
This patch is done by sed scripts and changes back some incorrect
__pci_remove_bus_device changes.
Suggested-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Fix debug variable from module parameter to be really bool to
fix 'warning: return from incompatible pointer type'.
Acked-by: Scott Murray <scott@spiteful.org>
Signed-off-by: Danny Kukawka <danny.kukawka@bisect.de>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
On a system with a repeater on the system board to support gen2 hotplug,
we found that when an ExpressModule is removed from some slots,
/var/log/messages will be full of "card present/not present" warnings.
It turns out the root complex is continually trying to train the link to
the repeater because the repeater has not been reset.
This patch will disable the link at removal time to allow the repeater
to be reset properly. This also prevents a potential AER message at
removal time.
Also, when testing hotplug on a system under development, we found if we
boot the system without an EM installed, and later hot-add an EM, it
does not work with Linux, but another OS is ok. The root cause is that
BIOS left link disabled when slot was empty at boot time, and other OS
is modifying the link disable bit in link ctrl during power on/off.
So we should do the same thing to disable/enable link during power off/on.
-v2: check link DLLA bit instead of 100ms waiting.
Separate link disable/enable functions to another patch.
Signed-off-by: Yinghai Lu <yinghai.lu@oracle.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
A few changes:
- remove the 'inline' and let the complier decide
- return a bool to indicate whether the link was active
- add a debug message to indicate link state when it beocmes active
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
During reviewing
| PCI: pciehp: wait 1000 ms before Link Training check
Linus said:
>...
> That's a *long* time, and it's irritating to the user. It makes the
> user think "the machine is slow".
>...
> And quite frankly, an unconditional one-second delay here seems bad.
>Two seconds was unacceptable, one second is just bad.
Try to access the pci conf of a pci device that is supposed to show up
in 1s. If we can read back a valid vendor/device id, we can return
early.
Related discussion could be found:
https://lkml.org/lkml/2011/12/6/339
-v2: seperate code to pci_bus_read_dev_vendor_id() from pci_scan_device()
and reuse it from pciehp code. Suggested by Matthew Wilcox.
-v3: According to Kenj, don't use array in stack, and don't wait too long
for crs, also return fail status if not found.
Also separate pci_bus_dev_read_vendor_id() change to another patch.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Add missing iounmap in error handling code, in a case where the function
already preforms iounmap on some other execution path.
A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)
// <smpl>
@@
expression e;
statement S,S1;
int ret;
@@
e = \(ioremap\|ioremap_nocache\)(...)
... when != iounmap(e)
if (<+...e...+>) S
... when any
when != iounmap(e)
*if (...)
{ ... when != iounmap(e)
return ...; }
... when any
iounmap(e);
// </smpl>
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Bjorn Helgaas