| Age | Commit message (Collapse) | Author | Files | Lines |
|---|
|
When a hotplug driver calls pci_hp_register(), all steps necessary for
registration are carried out in one go, including creation of a kobject
and addition to sysfs. That's a problem for pciehp once it's converted
to enable/disable the slot exclusively from the IRQ thread: The thread
needs to be spawned after creation of the kobject (because it uses the
kobject's name), but before addition to sysfs (because it will handle
enable/disable requests submitted via sysfs).
pci_hp_deregister() does offer a ->release callback that's invoked
after deletion from sysfs and before destruction of the kobject. But
because pci_hp_register() doesn't offer a counterpart, hotplug drivers'
->probe and ->remove code becomes asymmetric, which is error prone
as recently discovered use-after-free bugs in pciehp's ->remove hook
have shown.
In a sense, this appears to be a case of the midlayer antipattern:
"The core thesis of the "midlayer mistake" is that midlayers are
bad and should not exist. That common functionality which it is
so tempting to put in a midlayer should instead be provided as
library routines which can [be] used, augmented, or ignored by
each bottom level driver independently. Thus every subsystem
that supports multiple implementations (or drivers) should
provide a very thin top layer which calls directly into the
bottom layer drivers, and a rich library of support code that
eases the implementation of those drivers. This library is
available to, but not forced upon, those drivers."
-- Neil Brown (2009), https://lwn.net/Articles/336262/
The presence of midlayer traits in the PCI hotplug core might be ascribed
to its age: When it was introduced in February 2002, the blessings of a
library approach might not have been well known:
https://git.kernel.org/tglx/history/c/a8a2069f432c
For comparison, the driver core does offer split functions for creating
a kobject (device_initialize()) and addition to sysfs (device_add()) as
an alternative to carrying out everything at once (device_register()).
This was introduced in October 2002:
https://git.kernel.org/tglx/history/c/8b290eb19962
The odd ->release callback in the PCI hotplug core was added in 2003:
https://git.kernel.org/tglx/history/c/69f8d663b595
Clearly, a library approach would not force every hotplug driver to
implement a ->release callback, but rather allow the driver to remove
the sysfs files, release its data structures and finally destroy the
kobject. Alternatively, a driver may choose to remove everything with
pci_hp_deregister(), then release its data structures.
To this end, offer drivers pci_hp_initialize() and pci_hp_add() as a
split-up version of pci_hp_register(). Likewise, offer pci_hp_del()
and pci_hp_destroy() as a split-up version of pci_hp_deregister().
Eliminate the ->release callback and move its code into each driver's
teardown routine.
Declare pci_hp_deregister() void, in keeping with the usual kernel
pattern that enablement can fail, but disablement cannot. It only
returned an error if the caller passed in a NULL pointer or a slot which
has never or is no longer registered or is sharing its name with another
slot. Those would be bugs, so WARN about them. Few hotplug drivers
actually checked the return value and those that did only printed a
useless error message to dmesg. Remove that.
For most drivers the conversion was straightforward since it doesn't
matter whether the code in the ->release callback is executed before or
after destruction of the kobject. But in the case of ibmphp, it was
unclear to me whether setting slot_cur->ctrl and slot_cur->bus_on to
NULL needs to happen before the kobject is destroyed, so I erred on
the side of caution and ensured that the order stays the same. Another
nontrivial case is pnv_php, I've found the list and kref logic difficult
to understand, however my impression was that it is safe to delete the
list element and drop the references until after the kobject is
destroyed.
Signed-off-by: Lukas Wunner <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Acked-by: Andy Shevchenko <[email protected]> # drivers/platform/x86
Cc: Rafael J. Wysocki <[email protected]>
Cc: Len Brown <[email protected]>
Cc: Scott Murray <[email protected]>
Cc: Benjamin Herrenschmidt <[email protected]>
Cc: Paul Mackerras <[email protected]>
Cc: Michael Ellerman <[email protected]>
Cc: Gavin Shan <[email protected]>
Cc: Sebastian Ott <[email protected]>
Cc: Gerald Schaefer <[email protected]>
Cc: Corentin Chary <[email protected]>
Cc: Darren Hart <[email protected]>
Cc: Andy Shevchenko <[email protected]>
|
|
Previously the slot workqueue was used to handle events and enable or
disable the slot. That's no longer the case as those tasks are done
synchronously in the IRQ thread. The slot workqueue is thus merely used
to handle a button press after the 5 second delay and only one such work
item may be in flight at any given time. A separate workqueue isn't
necessary for this simple task, so use the system workqueue instead.
Signed-off-by: Lukas Wunner <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
|
|
Up until now, pciehp's IRQ handler schedules a work item for each event,
which in turn schedules a work item to enable or disable the slot. This
double indirection was necessary because sleeping wasn't allowed in the
IRQ handler.
However it is now that pciehp has been converted to threaded IRQ handling
and polling, so handle events synchronously in pciehp_ist() and remove
the work item infrastructure (with the exception of work items to handle
a button press after the 5 second delay).
For link or presence change events, move the register read to determine
the current link or presence state behind acquisition of the slot lock
to prevent it from becoming stale while the lock is contended.
Signed-off-by: Lukas Wunner <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
|
|
If the attention button is pressed to power on the slot AND the user
powers on the slot via sysfs before 5 seconds have elapsed AND powering
on the slot fails because either the slot is unoccupied OR the latch is
open, we neglect turning off the green LED so it keeps on blinking.
That's because the error path of pciehp_sysfs_enable_slot() doesn't call
pciehp_green_led_off(), unlike pciehp_power_thread() which does.
The bug has been present since 2004 when the driver was introduced.
Fix by deduplicating common code in pciehp_sysfs_enable_slot() and
pciehp_power_thread() into a wrapper function pciehp_enable_slot() and
renaming the existing function to __pciehp_enable_slot(). Same for
pciehp_disable_slot(). This will also simplify the upcoming rework of
pciehp's event handling.
Signed-off-by: Lukas Wunner <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
|
|
We've just converted pciehp to threaded IRQ handling, but still cannot
sleep in pciehp_ist() because the function is also called in poll mode,
which runs in softirq context (from a timer).
Convert poll mode to a kthread so that pciehp_ist() always runs in task
context.
Signed-off-by: Lukas Wunner <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Cc: Thomas Gleixner <[email protected]>
|
|
pciehp's IRQ handler queues up a work item for each event signaled by
the hardware. A more modern alternative is to let a long running
kthread service the events. The IRQ handler's sole job is then to check
whether the IRQ originated from the device in question, acknowledge its
receipt to the hardware to quiesce the interrupt and wake up the kthread.
One benefit is reduced latency to handle the IRQ, which is a necessity
for realtime environments. Another benefit is that we can make pciehp
simpler and more robust by handling events synchronously in process
context, rather than asynchronously by queueing up work items. pciehp's
usage of work items is a historic artifact, it predates the introduction
of threaded IRQ handlers by two years. (The former was introduced in
2007 with commit 5d386e1ac402 ("pciehp: Event handling rework"), the
latter in 2009 with commit 3aa551c9b4c4 ("genirq: add threaded interrupt
handler support").)
Convert pciehp to threaded IRQ handling by retrieving the pending events
in pciehp_isr(), saving them for later consumption by the thread handler
pciehp_ist() and clearing them in the Slot Status register.
By clearing the Slot Status (and thereby acknowledging the events) in
pciehp_isr(), we can avoid requesting the IRQ with IRQF_ONESHOT, which
would have the unpleasant side effect of starving devices sharing the
IRQ until pciehp_ist() has finished.
pciehp_isr() does not count how many times each event occurred, but
merely records the fact *that* an event occurred. If the same event
occurs a second time before pciehp_ist() is woken, that second event
will not be recorded separately, which is problematic according to
commit fad214b0aa72 ("PCI: pciehp: Process all hotplug events before
looking for new ones") because we may miss removal of a card in-between
two back-to-back insertions. We're about to make pciehp_ist() resilient
to missed events. The present commit regresses the driver's behavior
temporarily in order to separate the changes into reviewable chunks.
This doesn't affect regular slow-motion hotplug, only plug-unplug-plug
operations that happen in a timespan shorter than wakeup of the IRQ
thread.
Signed-off-by: Lukas Wunner <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Mayurkumar Patel <[email protected]>
Cc: Kenji Kaneshige <[email protected]>
|
|
Document the driver's data structures to lower the barrier to entry for
contributors.
Signed-off-by: Lukas Wunner <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
|
|
Since commit 0f4bd8014db5 ("PCI: hotplug: Drop checking of PCI_BRIDGE_
CONTROL in *_unconfigure_device()"), pciehp_unconfigure_device() can no
longer fail, so declare it and its sole caller remove_board() void, in
keeping with the usual kernel pattern that enablement can fail, but
disablement cannot. No functional change intended.
Signed-off-by: Lukas Wunner <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Cc: Mika Westerberg <[email protected]>
|
|
pciehp_disable_slot() checks if the ctrl attribute of the slot is NULL
and bails out if so. However the function is not called prior to the
attribute being set in pcie_init_slot(), and pcie_init_slot() is not
called if ctrl is NULL. So the check is unnecessary. Drop it.
It has been present ever since the driver was introduced in 2004, but it
was already unnecessary back then:
https://git.kernel.org/tglx/history/c/c16b4b14d980
Signed-off-by: Lukas Wunner <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
|
|
Commit b440bde74f04 ("PCI: Add pci_ignore_hotplug() to ignore hotplug
events for a device") iterates over the devices on a hotplug port's
subordinate bus in pciehp's IRQ handler without acquiring pci_bus_sem.
It is thus possible for a user to cause a crash by concurrently
manipulating the device list, e.g. by disabling slot power via sysfs
on a different CPU or by initiating a remove/rescan via sysfs.
This can't be fixed by acquiring pci_bus_sem because it may sleep.
The simplest fix is to avoid the list iteration altogether and just
check the ignore_hotplug flag on the port itself. This works because
pci_ignore_hotplug() sets the flag both on the device as well as on its
parent bridge.
We do lose the ability to print the name of the device blocking hotplug
in the debug message, but that's probably bearable.
Fixes: b440bde74f04 ("PCI: Add pci_ignore_hotplug() to ignore hotplug events for a device")
Signed-off-by: Lukas Wunner <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Cc: [email protected]
|
|
When pciehp is unbound (e.g. on unplug of a Thunderbolt device), the
hotplug_slot struct is deregistered and thus freed before freeing the
IRQ. The IRQ handler and the work items it schedules print the slot
name referenced from the freed structure in various informational and
debug log messages, each time resulting in a quadruple dereference of
freed pointers (hotplug_slot -> pci_slot -> kobject -> name).
At best the slot name is logged as "(null)", at worst kernel memory is
exposed in logs or the driver crashes:
pciehp 0000:10:00.0:pcie204: Slot((null)): Card not present
An attacker may provoke the bug by unplugging multiple devices on a
Thunderbolt daisy chain at once. Unplugging can also be simulated by
powering down slots via sysfs. The bug is particularly easy to trigger
in poll mode.
It has been present since the driver's introduction in 2004:
https://git.kernel.org/tglx/history/c/c16b4b14d980
Fix by rearranging teardown such that the IRQ is freed first. Run the
work items queued by the IRQ handler to completion before freeing the
hotplug_slot struct by draining the work queue from the ->release_slot
callback which is invoked by pci_hp_deregister().
Signed-off-by: Lukas Wunner <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Cc: [email protected] # v2.6.4
|
|
If addition of sysfs files fails on registration of a hotplug slot, the
struct pci_slot as well as the entry in the slot_list is leaked. The
issue has been present since the hotplug core was introduced in 2002:
https://git.kernel.org/tglx/history/c/a8a2069f432c
Perhaps the idea was that even though sysfs addition fails, the slot
should still be usable. But that's not how drivers use the interface,
they abort probe if a non-zero value is returned.
Signed-off-by: Lukas Wunner <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Cc: [email protected] # v2.4.15+
Cc: Greg Kroah-Hartman <[email protected]>
|
|
Ten years ago, commit 58319b802a61 ("PCI: Hotplug core: remove 'name'")
dropped the name element from struct hotplug_slot but neglected to update
the skeleton driver.
That same year, commit f46753c5e354 ("PCI: introduce pci_slot") raised the
number of arguments to pci_hp_register() from one to four.
Fourteen years ago, historic commit 7ab60fc1b8e7 ("PCI Hotplug skeleton:
final cleanups") removed all usages of the retval variable from
pcihp_skel_init() but not the variable itself, provoking a compiler
warning: https://git.kernel.org/tglx/history/c/7ab60fc1b8e7
It seems fair to assume the driver hasn't been used as a template for a new
driver in a while. Per Bjorn's and Christoph's preference, delete it.
Signed-off-by: Lukas Wunner <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Cc: Christoph Hellwig <[email protected]>
|
|
The pci_error_handlers.slot_reset() callback is only used for non-bridge
devices (see broadcast_error_message()). Since portdrv only binds to
bridges, we don't need pcie_portdrv_slot_reset(), so remove it.
Signed-off-by: Oza Pawandeep <[email protected]>
[bhelgaas: changelog, remove pcie_portdrv_slot_reset() completely]
Signed-off-by: Bjorn Helgaas <[email protected]>
|
|
In case of correctable error, the Correctable Error Detected bit in the
Device Status register is set. Clear it after handling the error.
Signed-off-by: Oza Pawandeep <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
|
|
Clear the device status bits while handling both ERR_FATAL and ERR_NONFATAL
cases.
Signed-off-by: Oza Pawandeep <[email protected]>
[bhelgaas: rename to pci_aer_clear_device_status(), declare internal to PCI
core instead of exposing it everywhere]
Signed-off-by: Bjorn Helgaas <[email protected]>
|
|
broadcast_error_message() is only used for ERR_NONFATAL events, when the
state is always pci_channel_io_normal, so remove the unused alternate path.
Signed-off-by: Oza Pawandeep <[email protected]>
[bhelgaas: changelog]
Signed-off-by: Bjorn Helgaas <[email protected]>
|
|
aer_error_resume() clears all ERR_NONFATAL error status bits. This is
exactly what pci_cleanup_aer_uncorrect_error_status(), so use that instead
of duplicating the code.
Signed-off-by: Oza Pawandeep <[email protected]>
[bhelgaas: split to separate patch]
Signed-off-by: Bjorn Helgaas <[email protected]>
|
|
pci_cleanup_aer_uncorrect_error_status() is called by driver .slot_reset()
methods when handling ERR_NONFATAL errors. Previously this cleared *all*
the bits, including ERR_FATAL bits.
Since we're only handling ERR_NONFATAL errors, clear only the ERR_NONFATAL
error status bits.
Signed-off-by: Oza Pawandeep <[email protected]>
[bhelgaas: split to separate patch]
Signed-off-by: Bjorn Helgaas <[email protected]>
|
|
During recovery from fatal errors, we previously called
pci_cleanup_aer_uncorrect_error_status(), which cleared *all* uncorrectable
error status bits (both ERR_FATAL and ERR_NONFATAL).
Instead, call a new pci_aer_clear_fatal_status() that clears only the
ERR_FATAL bits (as indicated by the PCI_ERR_UNCOR_SEVER register).
Based-on-patch-by: Oza Pawandeep <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
|
|
Simplify waiting for the contained link to become inactive, removing the
indirection to a unnecessary DPC-specific handler.
Signed-off-by: Keith Busch <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Reviewed-by: Sinan Kaya <[email protected]>
Reviewed-by: Oza Pawandeep <[email protected]>
|
|
Remove the work struct that was being used to handle a DPC event and use a
threaded IRQ instead.
Signed-off-by: Keith Busch <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Reviewed-by: Sinan Kaya <[email protected]>
Reviewed-by: Oza Pawandeep <[email protected]>
|
|
A DPC enabled device suppresses ERR_(NON)FATAL messages, preventing the AER
handler from reporting error details. If the DPC trigger reason says the
downstream port detected the error, collect the AER uncorrectable status
for logging, then clear the status.
Signed-off-by: Keith Busch <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Reviewed-by: Sinan Kaya <[email protected]>
Reviewed-by: Oza Pawandeep <[email protected]>
|
|
We don't need to save the rp pio status across multiple contexts as all
DPC event handling occurs in a single work queue context.
Signed-off-by: Keith Busch <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Reviewed-by: Sinan Kaya <[email protected]>
Reviewed-by: Oza Pawandeep <[email protected]>
|
|
Move all event handling to the existing work queue, which will
make it simpler to pass event information to the handler.
Signed-off-by: Keith Busch <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Reviewed-by: Sinan Kaya <[email protected]>
Reviewed-by: Oza Pawandeep <[email protected]>
|
|
Now that the DPC driver clears the interrupt status before exiting the
IRQ handler, we don't need to abuse the DPC control register to know if
a shared interrupt is for a new DPC event: a DPC port can not trigger
a second interrupt until the host clears the trigger status later in the
work queue handler.
Signed-off-by: Keith Busch <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Reviewed-by: Sinan Kaya <[email protected]>
Reviewed-by: Oza Pawandeep <[email protected]>
|
|
According to the documentation, "pcie_ports=native", linux should use
native AER and DPC services. While that is true for the _OSC method
parsing, this is not the only place that is checked. Should the HEST
list PCIe ports as firmware-first, linux will not use native services.
This happens because aer_acpi_firmware_first() doesn't take 'pcie_ports'
into account. This is wrong. DPC uses the same logic when it decides
whether to load or not, so fixing this also fixes DPC not loading.
Signed-off-by: Alexandru Gagniuc <[email protected]>
[bhelgaas: return "false" from bool function (from kbuild robot)]
Signed-off-by: Bjorn Helgaas <[email protected]>
|
|
Add sysfs attributes for rootport statistics (that are cumulative of all
the ERR_* messages seen on this PCI hierarchy).
Signed-off-by: Rajat Jain <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
|
|
Add sysfs attributes to provide total and breakdown of the AERs seen,
into different type of correctable, fatal and nonfatal errors:
/sys/bus/pci/devices/<dev>/aer_dev_correctable
/sys/bus/pci/devices/<dev>/aer_dev_fatal
/sys/bus/pci/devices/<dev>/aer_dev_nonfatal
Signed-off-by: Rajat Jain <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
|
|
Define a structure to hold the AER statistics. There are 2 groups of
statistics: dev_* counters that are to be collected for all AER capable
devices and rootport_* counters that are collected for all (AER capable)
rootports only. Allocate and free this structure when device is added or
released (thus counters survive the lifetime of the device).
Signed-off-by: Rajat Jain <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
|
|
Since pci_aer_init() and pci_no_aer() are used only internally, move their
declarations to the PCI internal header file. Also, no one cares about
return value of pci_aer_init(), so make it void.
Signed-off-by: Rajat Jain <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
|
|
lspci uses abbreviated naming for AER error strings. Adopt the same naming
convention for the AER printing so they match.
Signed-off-by: Tyler Baicar <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Reviewed-by: Oza Pawandeep <[email protected]>
|
|
Export some common AER functions and structures for other PCI core drivers
to use. Since this is making the function externally visible inside the
PCI core, prepend "aer_" to the function name.
Signed-off-by: Keith Busch <[email protected]>
[bhelgaas: move AER declarations from linux/aer.h to drivers/pci/pci.h]
Signed-off-by: Bjorn Helgaas <[email protected]>
Reviewed-by: Sinan Kaya <[email protected]>
Reviewed-by: Oza Pawandeep <[email protected]>
|
|
When testing the R-Car PCIe driver on the Condor board, if the PCIe PHY
driver was left disabled, the kernel crashed with this BUG:
kernel BUG at lib/ioremap.c:72!
Internal error: Oops - BUG: 0 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 PID: 39 Comm: kworker/0:1 Not tainted 4.17.0-dirty #1092
Hardware name: Renesas Condor board based on r8a77980 (DT)
Workqueue: events deferred_probe_work_func
pstate: 80000005 (Nzcv daif -PAN -UAO)
pc : ioremap_page_range+0x370/0x3c8
lr : ioremap_page_range+0x40/0x3c8
sp : ffff000008da39e0
x29: ffff000008da39e0 x28: 00e8000000000f07
x27: ffff7dfffee00000 x26: 0140000000000000
x25: ffff7dfffef00000 x24: 00000000000fe100
x23: ffff80007b906000 x22: ffff000008ab8000
x21: ffff000008bb1d58 x20: ffff7dfffef00000
x19: ffff800009c30fb8 x18: 0000000000000001
x17: 00000000000152d0 x16: 00000000014012d0
x15: 0000000000000000 x14: 0720072007200720
x13: 0720072007200720 x12: 0720072007200720
x11: 0720072007300730 x10: 00000000000000ae
x9 : 0000000000000000 x8 : ffff7dffff000000
x7 : 0000000000000000 x6 : 0000000000000100
x5 : 0000000000000000 x4 : 000000007b906000
x3 : ffff80007c61a880 x2 : ffff7dfffeefffff
x1 : 0000000040000000 x0 : 00e80000fe100f07
Process kworker/0:1 (pid: 39, stack limit = 0x (ptrval))
Call trace:
ioremap_page_range+0x370/0x3c8
pci_remap_iospace+0x7c/0xac
pci_parse_request_of_pci_ranges+0x13c/0x190
rcar_pcie_probe+0x4c/0xb04
platform_drv_probe+0x50/0xbc
driver_probe_device+0x21c/0x308
__device_attach_driver+0x98/0xc8
bus_for_each_drv+0x54/0x94
__device_attach+0xc4/0x12c
device_initial_probe+0x10/0x18
bus_probe_device+0x90/0x98
deferred_probe_work_func+0xb0/0x150
process_one_work+0x12c/0x29c
worker_thread+0x200/0x3fc
kthread+0x108/0x134
ret_from_fork+0x10/0x18
Code: f9004ba2 54000080 aa0003fb 17ffff48 (d4210000)
It turned out that pci_remap_iospace() wasn't undone when the driver's
probe failed, and since devm_phy_optional_get() returned -EPROBE_DEFER,
the probe was retried, finally causing the BUG due to trying to remap
already remapped pages.
The V3 Semiconductor PCI driver has the same issue.
Replace devm_pci_remap_iospace() with its devm_ managed version to fix
the bug.
Fixes: 68a15eb7bd0c ("PCI: v3-semi: Add V3 Semiconductor PCI host driver")
Signed-off-by: Sergei Shtylyov <[email protected]>
[[email protected]: updated the commit log]
Signed-off-by: Lorenzo Pieralisi <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Reviewed-by: Linus Walleij <[email protected]>
|
|
When testing the R-Car PCIe driver on the Condor board, if the PCIe PHY
driver was left disabled, the kernel crashed with this BUG:
kernel BUG at lib/ioremap.c:72!
Internal error: Oops - BUG: 0 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 PID: 39 Comm: kworker/0:1 Not tainted 4.17.0-dirty #1092
Hardware name: Renesas Condor board based on r8a77980 (DT)
Workqueue: events deferred_probe_work_func
pstate: 80000005 (Nzcv daif -PAN -UAO)
pc : ioremap_page_range+0x370/0x3c8
lr : ioremap_page_range+0x40/0x3c8
sp : ffff000008da39e0
x29: ffff000008da39e0 x28: 00e8000000000f07
x27: ffff7dfffee00000 x26: 0140000000000000
x25: ffff7dfffef00000 x24: 00000000000fe100
x23: ffff80007b906000 x22: ffff000008ab8000
x21: ffff000008bb1d58 x20: ffff7dfffef00000
x19: ffff800009c30fb8 x18: 0000000000000001
x17: 00000000000152d0 x16: 00000000014012d0
x15: 0000000000000000 x14: 0720072007200720
x13: 0720072007200720 x12: 0720072007200720
x11: 0720072007300730 x10: 00000000000000ae
x9 : 0000000000000000 x8 : ffff7dffff000000
x7 : 0000000000000000 x6 : 0000000000000100
x5 : 0000000000000000 x4 : 000000007b906000
x3 : ffff80007c61a880 x2 : ffff7dfffeefffff
x1 : 0000000040000000 x0 : 00e80000fe100f07
Process kworker/0:1 (pid: 39, stack limit = 0x (ptrval))
Call trace:
ioremap_page_range+0x370/0x3c8
pci_remap_iospace+0x7c/0xac
pci_parse_request_of_pci_ranges+0x13c/0x190
rcar_pcie_probe+0x4c/0xb04
platform_drv_probe+0x50/0xbc
driver_probe_device+0x21c/0x308
__device_attach_driver+0x98/0xc8
bus_for_each_drv+0x54/0x94
__device_attach+0xc4/0x12c
device_initial_probe+0x10/0x18
bus_probe_device+0x90/0x98
deferred_probe_work_func+0xb0/0x150
process_one_work+0x12c/0x29c
worker_thread+0x200/0x3fc
kthread+0x108/0x134
ret_from_fork+0x10/0x18
Code: f9004ba2 54000080 aa0003fb 17ffff48 (d4210000)
It turned out that pci_remap_iospace() wasn't undone when the driver's
probe failed, and since devm_phy_optional_get() returned -EPROBE_DEFER,
the probe was retried, finally causing the BUG due to trying to remap
already remapped pages.
The MediaTek PCIe driver has the same issue.
Replace devm_pci_remap_iospace() with its devm_ managed counterpart
to fix the bug.
Fixes: 637cfacae96f ("PCI: mediatek: Add MediaTek PCIe host controller support")
Signed-off-by: Sergei Shtylyov <[email protected]>
[[email protected]: updated the commit log]
Signed-off-by: Lorenzo Pieralisi <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Reviewed-by: Linus Walleij <[email protected]>
|
|
When testing the R-Car PCIe driver on the Condor board, if
the PCIe PHY driver was left disabled, the kernel crashed with this BUG:
kernel BUG at lib/ioremap.c:72!
Internal error: Oops - BUG: 0 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 PID: 39 Comm: kworker/0:1 Not tainted 4.17.0-dirty #1092
Hardware name: Renesas Condor board based on r8a77980 (DT)
Workqueue: events deferred_probe_work_func
pstate: 80000005 (Nzcv daif -PAN -UAO)
pc : ioremap_page_range+0x370/0x3c8
lr : ioremap_page_range+0x40/0x3c8
sp : ffff000008da39e0
x29: ffff000008da39e0 x28: 00e8000000000f07
x27: ffff7dfffee00000 x26: 0140000000000000
x25: ffff7dfffef00000 x24: 00000000000fe100
x23: ffff80007b906000 x22: ffff000008ab8000
x21: ffff000008bb1d58 x20: ffff7dfffef00000
x19: ffff800009c30fb8 x18: 0000000000000001
x17: 00000000000152d0 x16: 00000000014012d0
x15: 0000000000000000 x14: 0720072007200720
x13: 0720072007200720 x12: 0720072007200720
x11: 0720072007300730 x10: 00000000000000ae
x9 : 0000000000000000 x8 : ffff7dffff000000
x7 : 0000000000000000 x6 : 0000000000000100
x5 : 0000000000000000 x4 : 000000007b906000
x3 : ffff80007c61a880 x2 : ffff7dfffeefffff
x1 : 0000000040000000 x0 : 00e80000fe100f07
Process kworker/0:1 (pid: 39, stack limit = 0x (ptrval))
Call trace:
ioremap_page_range+0x370/0x3c8
pci_remap_iospace+0x7c/0xac
pci_parse_request_of_pci_ranges+0x13c/0x190
rcar_pcie_probe+0x4c/0xb04
platform_drv_probe+0x50/0xbc
driver_probe_device+0x21c/0x308
__device_attach_driver+0x98/0xc8
bus_for_each_drv+0x54/0x94
__device_attach+0xc4/0x12c
device_initial_probe+0x10/0x18
bus_probe_device+0x90/0x98
deferred_probe_work_func+0xb0/0x150
process_one_work+0x12c/0x29c
worker_thread+0x200/0x3fc
kthread+0x108/0x134
ret_from_fork+0x10/0x18
Code: f9004ba2 54000080 aa0003fb 17ffff48 (d4210000)
It turned out that pci_remap_iospace() wasn't undone when the driver's
probe failed, and since devm_phy_optional_get() returned -EPROBE_DEFER,
the probe was retried, finally causing the BUG due to trying to remap
already remapped pages.
The Faraday PCI driver has the same issue. Replace pci_remap_iospace()
with its devm_ managed version to fix the bug.
Fixes: d3c68e0a7e34 ("PCI: faraday: Add Faraday Technology FTPCI100 PCI Host Bridge driver")
Signed-off-by: Sergei Shtylyov <[email protected]>
[[email protected]: updated the commit log]
Signed-off-by: Lorenzo Pieralisi <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Reviewed-by: Linus Walleij <[email protected]>
|
|
When testing the R-Car PCIe driver on the Condor board, if the PCIe PHY
driver was left disabled, the kernel crashed with this BUG:
kernel BUG at lib/ioremap.c:72!
Internal error: Oops - BUG: 0 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 PID: 39 Comm: kworker/0:1 Not tainted 4.17.0-dirty #1092
Hardware name: Renesas Condor board based on r8a77980 (DT)
Workqueue: events deferred_probe_work_func
pstate: 80000005 (Nzcv daif -PAN -UAO)
pc : ioremap_page_range+0x370/0x3c8
lr : ioremap_page_range+0x40/0x3c8
sp : ffff000008da39e0
x29: ffff000008da39e0 x28: 00e8000000000f07
x27: ffff7dfffee00000 x26: 0140000000000000
x25: ffff7dfffef00000 x24: 00000000000fe100
x23: ffff80007b906000 x22: ffff000008ab8000
x21: ffff000008bb1d58 x20: ffff7dfffef00000
x19: ffff800009c30fb8 x18: 0000000000000001
x17: 00000000000152d0 x16: 00000000014012d0
x15: 0000000000000000 x14: 0720072007200720
x13: 0720072007200720 x12: 0720072007200720
x11: 0720072007300730 x10: 00000000000000ae
x9 : 0000000000000000 x8 : ffff7dffff000000
x7 : 0000000000000000 x6 : 0000000000000100
x5 : 0000000000000000 x4 : 000000007b906000
x3 : ffff80007c61a880 x2 : ffff7dfffeefffff
x1 : 0000000040000000 x0 : 00e80000fe100f07
Process kworker/0:1 (pid: 39, stack limit = 0x (ptrval))
Call trace:
ioremap_page_range+0x370/0x3c8
pci_remap_iospace+0x7c/0xac
pci_parse_request_of_pci_ranges+0x13c/0x190
rcar_pcie_probe+0x4c/0xb04
platform_drv_probe+0x50/0xbc
driver_probe_device+0x21c/0x308
__device_attach_driver+0x98/0xc8
bus_for_each_drv+0x54/0x94
__device_attach+0xc4/0x12c
device_initial_probe+0x10/0x18
bus_probe_device+0x90/0x98
deferred_probe_work_func+0xb0/0x150
process_one_work+0x12c/0x29c
worker_thread+0x200/0x3fc
kthread+0x108/0x134
ret_from_fork+0x10/0x18
Code: f9004ba2 54000080 aa0003fb 17ffff48 (d4210000)
It turned out that pci_remap_iospace() wasn't undone when the driver's
probe failed, and since devm_phy_optional_get() returned -EPROBE_DEFER,
the probe was retried, finally causing the BUG due to trying to remap
already remapped pages.
The Aardvark PCI controller driver has the same issue.
Replace pci_remap_iospace() with its devm_ managed version to fix the bug.
Fixes: 8c39d710363c ("PCI: aardvark: Add Aardvark PCI host controller driver")
Signed-off-by: Sergei Shtylyov <[email protected]>
[[email protected]: updated the commit log]
Signed-off-by: Lorenzo Pieralisi <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Reviewed-by: Thomas Petazzoni <[email protected]>
Reviewed-by: Linus Walleij <[email protected]>
|
|
When testing the R-Car PCIe driver on the Condor board, if the PCIe PHY
driver is left disabled, the kernel crashed with this BUG:
kernel BUG at lib/ioremap.c:72!
Internal error: Oops - BUG: 0 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 PID: 39 Comm: kworker/0:1 Not tainted 4.17.0-dirty #1092
Hardware name: Renesas Condor board based on r8a77980 (DT)
Workqueue: events deferred_probe_work_func
pstate: 80000005 (Nzcv daif -PAN -UAO)
pc : ioremap_page_range+0x370/0x3c8
lr : ioremap_page_range+0x40/0x3c8
sp : ffff000008da39e0
x29: ffff000008da39e0 x28: 00e8000000000f07
x27: ffff7dfffee00000 x26: 0140000000000000
x25: ffff7dfffef00000 x24: 00000000000fe100
x23: ffff80007b906000 x22: ffff000008ab8000
x21: ffff000008bb1d58 x20: ffff7dfffef00000
x19: ffff800009c30fb8 x18: 0000000000000001
x17: 00000000000152d0 x16: 00000000014012d0
x15: 0000000000000000 x14: 0720072007200720
x13: 0720072007200720 x12: 0720072007200720
x11: 0720072007300730 x10: 00000000000000ae
x9 : 0000000000000000 x8 : ffff7dffff000000
x7 : 0000000000000000 x6 : 0000000000000100
x5 : 0000000000000000 x4 : 000000007b906000
x3 : ffff80007c61a880 x2 : ffff7dfffeefffff
x1 : 0000000040000000 x0 : 00e80000fe100f07
Process kworker/0:1 (pid: 39, stack limit = 0x (ptrval))
Call trace:
ioremap_page_range+0x370/0x3c8
pci_remap_iospace+0x7c/0xac
pci_parse_request_of_pci_ranges+0x13c/0x190
rcar_pcie_probe+0x4c/0xb04
platform_drv_probe+0x50/0xbc
driver_probe_device+0x21c/0x308
__device_attach_driver+0x98/0xc8
bus_for_each_drv+0x54/0x94
__device_attach+0xc4/0x12c
device_initial_probe+0x10/0x18
bus_probe_device+0x90/0x98
deferred_probe_work_func+0xb0/0x150
process_one_work+0x12c/0x29c
worker_thread+0x200/0x3fc
kthread+0x108/0x134
ret_from_fork+0x10/0x18
Code: f9004ba2 54000080 aa0003fb 17ffff48 (d4210000)
It turned out that pci_remap_iospace() wasn't undone when the driver's
probe failed, and since devm_phy_optional_get() returned -EPROBE_DEFER,
the probe was retried, finally causing the BUG due to trying to remap
already remapped pages.
The DesignWare PCIe controller driver has the same issue.
Replace devm_pci_remap_iospace() with a devm_ managed version to fix the
bug.
Fixes: cbce7900598c ("PCI: designware: Make driver arch-agnostic")
Signed-off-by: Sergei Shtylyov <[email protected]>
[[email protected]: updated the commit log]
Signed-off-by: Lorenzo Pieralisi <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Reviewed-by: Linus Walleij <[email protected]>
Acked-by: Jingoo Han <[email protected]>
|
|
When testing the R-Car PCIe driver on the Condor board, if the PCIe PHY
driver was left disabled, the kernel crashed with this BUG:
kernel BUG at lib/ioremap.c:72!
Internal error: Oops - BUG: 0 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 PID: 39 Comm: kworker/0:1 Not tainted 4.17.0-dirty #1092
Hardware name: Renesas Condor board based on r8a77980 (DT)
Workqueue: events deferred_probe_work_func
pstate: 80000005 (Nzcv daif -PAN -UAO)
pc : ioremap_page_range+0x370/0x3c8
lr : ioremap_page_range+0x40/0x3c8
sp : ffff000008da39e0
x29: ffff000008da39e0 x28: 00e8000000000f07
x27: ffff7dfffee00000 x26: 0140000000000000
x25: ffff7dfffef00000 x24: 00000000000fe100
x23: ffff80007b906000 x22: ffff000008ab8000
x21: ffff000008bb1d58 x20: ffff7dfffef00000
x19: ffff800009c30fb8 x18: 0000000000000001
x17: 00000000000152d0 x16: 00000000014012d0
x15: 0000000000000000 x14: 0720072007200720
x13: 0720072007200720 x12: 0720072007200720
x11: 0720072007300730 x10: 00000000000000ae
x9 : 0000000000000000 x8 : ffff7dffff000000
x7 : 0000000000000000 x6 : 0000000000000100
x5 : 0000000000000000 x4 : 000000007b906000
x3 : ffff80007c61a880 x2 : ffff7dfffeefffff
x1 : 0000000040000000 x0 : 00e80000fe100f07
Process kworker/0:1 (pid: 39, stack limit = 0x (ptrval))
Call trace:
ioremap_page_range+0x370/0x3c8
pci_remap_iospace+0x7c/0xac
pci_parse_request_of_pci_ranges+0x13c/0x190
rcar_pcie_probe+0x4c/0xb04
platform_drv_probe+0x50/0xbc
driver_probe_device+0x21c/0x308
__device_attach_driver+0x98/0xc8
bus_for_each_drv+0x54/0x94
__device_attach+0xc4/0x12c
device_initial_probe+0x10/0x18
bus_probe_device+0x90/0x98
deferred_probe_work_func+0xb0/0x150
process_one_work+0x12c/0x29c
worker_thread+0x200/0x3fc
kthread+0x108/0x134
ret_from_fork+0x10/0x18
Code: f9004ba2 54000080 aa0003fb 17ffff48 (d4210000)
It turned out that pci_remap_iospace() wasn't undone when the driver's
probe failed, and since devm_phy_optional_get() returned -EPROBE_DEFER,
the probe was retried, finally causing the BUG due to trying to remap
already remapped pages.
The Versatile PCI controller driver has the same issue.
Replace pci_remap_iospace() with the devm_ managed version to fix the bug.
Fixes: b7e78170efd4 ("PCI: versatile: Add DT-based ARM Versatile PB PCIe host driver")
Signed-off-by: Sergei Shtylyov <[email protected]>
[[email protected]: updated the commit log]
Signed-off-by: Lorenzo Pieralisi <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Reviewed-by: Linus Walleij <[email protected]>
|
|
When testing the R-Car PCIe driver on the Condor board, if the PCIe PHY
driver was left disabled, the kernel crashed with this BUG:
kernel BUG at lib/ioremap.c:72!
Internal error: Oops - BUG: 0 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 PID: 39 Comm: kworker/0:1 Not tainted 4.17.0-dirty #1092
Hardware name: Renesas Condor board based on r8a77980 (DT)
Workqueue: events deferred_probe_work_func
pstate: 80000005 (Nzcv daif -PAN -UAO)
pc : ioremap_page_range+0x370/0x3c8
lr : ioremap_page_range+0x40/0x3c8
sp : ffff000008da39e0
x29: ffff000008da39e0 x28: 00e8000000000f07
x27: ffff7dfffee00000 x26: 0140000000000000
x25: ffff7dfffef00000 x24: 00000000000fe100
x23: ffff80007b906000 x22: ffff000008ab8000
x21: ffff000008bb1d58 x20: ffff7dfffef00000
x19: ffff800009c30fb8 x18: 0000000000000001
x17: 00000000000152d0 x16: 00000000014012d0
x15: 0000000000000000 x14: 0720072007200720
x13: 0720072007200720 x12: 0720072007200720
x11: 0720072007300730 x10: 00000000000000ae
x9 : 0000000000000000 x8 : ffff7dffff000000
x7 : 0000000000000000 x6 : 0000000000000100
x5 : 0000000000000000 x4 : 000000007b906000
x3 : ffff80007c61a880 x2 : ffff7dfffeefffff
x1 : 0000000040000000 x0 : 00e80000fe100f07
Process kworker/0:1 (pid: 39, stack limit = 0x (ptrval))
Call trace:
ioremap_page_range+0x370/0x3c8
pci_remap_iospace+0x7c/0xac
pci_parse_request_of_pci_ranges+0x13c/0x190
rcar_pcie_probe+0x4c/0xb04
platform_drv_probe+0x50/0xbc
driver_probe_device+0x21c/0x308
__device_attach_driver+0x98/0xc8
bus_for_each_drv+0x54/0x94
__device_attach+0xc4/0x12c
device_initial_probe+0x10/0x18
bus_probe_device+0x90/0x98
deferred_probe_work_func+0xb0/0x150
process_one_work+0x12c/0x29c
worker_thread+0x200/0x3fc
kthread+0x108/0x134
ret_from_fork+0x10/0x18
Code: f9004ba2 54000080 aa0003fb 17ffff48 (d4210000)
It turned out that pci_remap_iospace() wasn't undone when the driver's
probe failed, and since devm_phy_optional_get() returned -EPROBE_DEFER,
the probe was retried, finally causing the BUG due to trying to remap
already remapped pages.
The X-Gene PCI controller driver has the same issue.
Replace pci_remap_iospace() with the devm_ managed version so that the
pages get unmapped automagically on any probe failure.
Fixes: 5f6b6ccdbe1c ("PCI: xgene: Add APM X-Gene PCIe driver")
Signed-off-by: Sergei Shtylyov <[email protected]>
[[email protected]: updated the commit log]
Signed-off-by: Lorenzo Pieralisi <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Reviewed-by: Linus Walleij <[email protected]>
|
|
When testing the R-Car PCIe driver on the Condor board, if the PCIe PHY
driver was left disabled, the kernel crashed with this BUG:
kernel BUG at lib/ioremap.c:72!
Internal error: Oops - BUG: 0 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 PID: 39 Comm: kworker/0:1 Not tainted 4.17.0-dirty #1092
Hardware name: Renesas Condor board based on r8a77980 (DT)
Workqueue: events deferred_probe_work_func
pstate: 80000005 (Nzcv daif -PAN -UAO)
pc : ioremap_page_range+0x370/0x3c8
lr : ioremap_page_range+0x40/0x3c8
sp : ffff000008da39e0
x29: ffff000008da39e0 x28: 00e8000000000f07
x27: ffff7dfffee00000 x26: 0140000000000000
x25: ffff7dfffef00000 x24: 00000000000fe100
x23: ffff80007b906000 x22: ffff000008ab8000
x21: ffff000008bb1d58 x20: ffff7dfffef00000
x19: ffff800009c30fb8 x18: 0000000000000001
x17: 00000000000152d0 x16: 00000000014012d0
x15: 0000000000000000 x14: 0720072007200720
x13: 0720072007200720 x12: 0720072007200720
x11: 0720072007300730 x10: 00000000000000ae
x9 : 0000000000000000 x8 : ffff7dffff000000
x7 : 0000000000000000 x6 : 0000000000000100
x5 : 0000000000000000 x4 : 000000007b906000
x3 : ffff80007c61a880 x2 : ffff7dfffeefffff
x1 : 0000000040000000 x0 : 00e80000fe100f07
Process kworker/0:1 (pid: 39, stack limit = 0x (ptrval))
Call trace:
ioremap_page_range+0x370/0x3c8
pci_remap_iospace+0x7c/0xac
pci_parse_request_of_pci_ranges+0x13c/0x190
rcar_pcie_probe+0x4c/0xb04
platform_drv_probe+0x50/0xbc
driver_probe_device+0x21c/0x308
__device_attach_driver+0x98/0xc8
bus_for_each_drv+0x54/0x94
__device_attach+0xc4/0x12c
device_initial_probe+0x10/0x18
bus_probe_device+0x90/0x98
deferred_probe_work_func+0xb0/0x150
process_one_work+0x12c/0x29c
worker_thread+0x200/0x3fc
kthread+0x108/0x134
ret_from_fork+0x10/0x18
Code: f9004ba2 54000080 aa0003fb 17ffff48 (d4210000)
It turned out that pci_remap_iospace() wasn't undone when the driver's
probe failed, and since devm_phy_optional_get() returned -EPROBE_DEFER,
the probe was retried, finally causing the BUG due to trying to remap
already remapped pages.
Introduce the devm_pci_remap_iospace() managed API and replace the
pci_remap_iospace() call with it to fix the bug.
Fixes: dbf9826d5797 ("PCI: generic: Convert to DT resource parsing API")
Signed-off-by: Sergei Shtylyov <[email protected]>
[[email protected]: split commit/updated the commit log]
Signed-off-by: Lorenzo Pieralisi <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Reviewed-by: Linus Walleij <[email protected]>
|
|
In preparation to enabling -Wimplicit-fallthrough, mark switch cases where
we are expecting to fall through.
Warning level 2 was used: -Wimplicit-fallthrough=2
Signed-off-by: Gustavo A. R. Silva <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
|
|
Some IDT switches incorrectly flag an ACS Source Validation error on
completions for config read requests even though PCIe r4.0, sec 6.12.1.1,
says that completions are never affected by ACS Source Validation. Here's
the text of IDT 89H32H8G3-YC, erratum #36:
Item #36 - Downstream port applies ACS Source Validation to Completions
Section 6.12.1.1 of the PCI Express Base Specification 3.1 states that
completions are never affected by ACS Source Validation. However,
completions received by a downstream port of the PCIe switch from a
device that has not yet captured a PCIe bus number are incorrectly
dropped by ACS Source Validation by the switch downstream port.
Workaround: Issue a CfgWr1 to the downstream device before issuing the
first CfgRd1 to the device. This allows the downstream device to capture
its bus number; ACS Source Validation no longer stops completions from
being forwarded by the downstream port. It has been observed that
Microsoft Windows implements this workaround already; however, some
versions of Linux and other operating systems may not.
When doing the first config read to probe for a device, if the device is
behind an IDT switch with this erratum:
1. Disable ACS Source Validation if enabled
2. Wait for device to become ready to accept config accesses (by using
the Config Request Retry Status mechanism)
3. Do a config write to the endpoint
4. Enable ACS Source Validation (if it was enabled to begin with)
The workaround suggested by IDT is basically only step 3, but we don't know
when the device is ready to accept config requests. That means we need to
do config reads until we receive a non-Config Request Retry Status, which
means we need to disable ACS SV temporarily.
Signed-off-by: James Puthukattukaran <[email protected]>
[bhelgaas: changelog, clean up whitespace, fold in unused variable fix
from Anders Roxell <[email protected]>]
Signed-off-by: Bjorn Helgaas <[email protected]>
Reviewed-by: Alex Williamson <[email protected]>
|
|
commit ef1433f717a2 ("PCI: endpoint: Create configfs entry for each
pci_epf_device_id table entry") while adding configfs entry for each
pci_epf_device_id table entry introduced a NULL pointer dereference error
when CONFIG_PCI_ENDPOINT_CONFIGFS is not enabled.
Fix it here.
Fixes: ef1433f717a2 ("PCI: endpoint: Create configfs entry for each
pci_epf_device_id table entry")
Signed-off-by: Kishon Vijay Abraham I <[email protected]>
[lorenzo.pieralisi: updated commit log]
Signed-off-by: Lorenzo Pieralisi <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
|
|
Commit de0aa7b2f97d ("PCI: hv: Fix 2 hang issues in hv_compose_msi_msg()")
uses local_bh_disable()/enable(), because hv_pci_onchannelcallback() can
also run in tasklet context as the channel event callback, so bottom halves
should be disabled to prevent a race condition.
With CONFIG_PROVE_LOCKING=y in the recent mainline, or old kernels that
don't have commit f71b74bca637 ("irq/softirqs: Use lockdep to assert IRQs
are disabled/enabled"), when the upper layer IRQ code calls
hv_compose_msi_msg() with local IRQs disabled, we'll see a warning at the
beginning of __local_bh_enable_ip():
IRQs not enabled as expected
WARNING: CPU: 0 PID: 408 at kernel/softirq.c:162 __local_bh_enable_ip
The warning exposes an issue in de0aa7b2f97d: local_bh_enable() can
potentially call do_softirq(), which is not supposed to run when local IRQs
are disabled. Let's fix this by using local_irq_save()/restore() instead.
Note: hv_pci_onchannelcallback() is not a hot path because it's only called
when the PCI device is hot added and removed, which is infrequent.
Fixes: de0aa7b2f97d ("PCI: hv: Fix 2 hang issues in hv_compose_msi_msg()")
Signed-off-by: Dexuan Cui <[email protected]>
Signed-off-by: Lorenzo Pieralisi <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Reviewed-by: Haiyang Zhang <[email protected]>
Cc: [email protected]
Cc: Stephen Hemminger <[email protected]>
Cc: K. Y. Srinivasan <[email protected]>
|
|
Before 8d85a7a4f2c9 ("PCI/IOV: Allow PF drivers to limit total_VFs to 0"),
pci_sriov_set_totalvfs(pdev, 0) meant "we can enable TotalVFs virtual
functions". After 8d85a7a4f2c9, it means "we can't enable *any* VFs".
That broke this scenario where nfp intends to remove any limit on the
number of VFs that can be enabled:
nfp_pci_probe
nfp_pcie_sriov_read_nfd_limit
nfp_rtsym_read_le("nfd_vf_cfg_max_vfs", &err)
pci_sriov_set_totalvfs(pf->pdev, 0) # if FW didn't expose a limit
...
# userspace writes N to sysfs "sriov_numvfs":
sriov_numvfs_store
pci_sriov_get_totalvfs # now returns 0
return -ERANGE
Prior to 8d85a7a4f2c9, pci_sriov_get_totalvfs() returned TotalVFs, but it
now returns 0.
Remove the pci_sriov_set_totalvfs(pdev, 0) calls so we don't limit the
number of VFs that can be enabled.
Fixes: 8d85a7a4f2c9 ("PCI/IOV: Allow PF drivers to limit total_VFs to 0")
Signed-off-by: Jakub Kicinski <[email protected]>
[bhelgaas: changelog]
Signed-off-by: Bjorn Helgaas <[email protected]>
|
|
The TotalVFs register in the SR-IOV capability is the hardware limit on the
number of VFs. A PF driver can limit the number of VFs further with
pci_sriov_set_totalvfs(). When the PF driver is removed, reset any VF
limit that was imposed by the driver because that limit may not apply to
other drivers.
Before 8d85a7a4f2c9 ("PCI/IOV: Allow PF drivers to limit total_VFs to 0"),
pci_sriov_set_totalvfs(pdev, 0) meant "we can enable TotalVFs virtual
functions", and the nfp driver used that to remove the VF limit when the
driver unloads.
8d85a7a4f2c9 broke that because instead of removing the VF limit,
pci_sriov_set_totalvfs(pdev, 0) actually sets the limit to zero, and that
limit persists even if another driver is loaded.
We could fix that by making the nfp driver reset the limit when it unloads,
but it seems more robust to do it in the PCI core instead of relying on the
driver.
The regression scenario is:
nfp_pci_probe (driver 1)
...
nfp_pci_remove
pci_sriov_set_totalvfs(pf->pdev, 0) # limits VFs to 0
...
nfp_pci_probe (driver 2)
nfp_rtsym_read_le("nfd_vf_cfg_max_vfs")
# no VF limit from firmware
Now driver 2 is broken because the VF limit is still 0 from driver 1.
Fixes: 8d85a7a4f2c9 ("PCI/IOV: Allow PF drivers to limit total_VFs to 0")
Signed-off-by: Jakub Kicinski <[email protected]>
[bhelgaas: changelog, rename functions]
Signed-off-by: Bjorn Helgaas <[email protected]>
|
|
The call to of_get_next_child() returns a node pointer with refcount
incremented thus it must be explicitly decremented here in the error
path and after the last usage.
Fixes: d3c68e0a7e34 ("PCI: faraday: Add Faraday Technology FTPCI100 PCI Host Bridge driver")
Signed-off-by: Nicholas Mc Guire <[email protected]>
[[email protected]: updated commit log]
Signed-off-by: Lorenzo Pieralisi <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Reviewed-by: Linus Walleij <[email protected]>
|
|
The call to of_get_next_child() returns a node pointer with
refcount incremented thus it must be explicitly decremented
here after the last usage.
Fixes: ab597d35ef11 ("PCI: xilinx-nwl: Add support for Xilinx NWL PCIe Host Controller")
Signed-off-by: Nicholas Mc Guire <[email protected]>
[[email protected]: updated commit log]
Signed-off-by: Lorenzo Pieralisi <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
|
|
The call to of_get_next_child() returns a node pointer with refcount
incremented thus it must be explicitly decremented here after the last
usage.
Fixes: 8961def56845 ("PCI: xilinx: Add Xilinx AXI PCIe Host Bridge IP driver")
Signed-off-by: Nicholas Mc Guire <[email protected]>
[[email protected]: reworked commit log]
Signed-off-by: Lorenzo Pieralisi <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
|