- Work around IDT switch ACS Source Validation erratum (James
Puthukattukaran)
- Emit diagnostics for all cases of PCIe Link downtraining (Links
operating slower than they're capable of) (Alexandru Gagniuc)
- Skip VFs when configuring Max Payload Size (Myron Stowe)
- Reduce Root Port Max Payload Size if necessary when hot-adding a device
below it (Myron Stowe)
* pci/enumeration:
PCI: Match Root Port's MPS to endpoint's MPSS as necessary
PCI: Skip MPS logic for Virtual Functions (VFs)
PCI: Check for PCIe Link downtraining
PCI: Workaround IDT switch ACS Source Validation erratum
- Defer DPC event handling to work queue (Keith Busch)
- Use threaded IRQ for DPC bottom half (Keith Busch)
- Print AER status while handling DPC events (Keith Busch)
* pci/dpc:
PCI/DPC: Remove indirection waiting for inactive link
PCI/DPC: Use threaded IRQ for bottom half handling
PCI/DPC: Print AER status in DPC event handling
PCI/DPC: Remove rp_pio_status from dpc struct
PCI/DPC: Defer event handling to work queue
PCI/DPC: Leave interrupts enabled while handling event
- Use sysfs_match_string() to simplify ASPM sysfs parsing (Andy
Shevchenko)
- Remove unnecessary includes of <linux/pci-aspm.h> (Bjorn Helgaas)
* pci/aspm:
PCI: Remove unnecessary include of <linux/pci-aspm.h>
iwlwifi: Remove unnecessary include of <linux/pci-aspm.h>
ath9k: Remove unnecessary include of <linux/pci-aspm.h>
igb: Remove unnecessary include of <linux/pci-aspm.h>
PCI/ASPM: Convert to use sysfs_match_string() helper
- Decode AER errors with names similar to "lspci" (Tyler Baicar)
- Expose AER statistics in sysfs (Rajat Jain)
- Clear AER status bits selectively based on the type of recovery (Oza
Pawandeep)
- Honor "pcie_ports=native" even if HEST sets FIRMWARE_FIRST (Alexandru
Gagniuc)
- Don't clear AER status bits if we're using the "Firmware-First"
strategy where firmware owns the registers (Alexandru Gagniuc)
* pci/aer:
PCI/AER: Don't clear AER bits if error handling is Firmware-First
PCI/AER: Remove duplicate PCI_EXP_AER_FLAGS definition
PCI/portdrv: Remove pcie_portdrv_err_handler.slot_reset
PCI/AER: Clear device status bits during ERR_COR handling
PCI/AER: Clear device status bits during ERR_FATAL and ERR_NONFATAL
PCI/AER: Remove ERR_FATAL code from ERR_NONFATAL path
PCI/AER: Factor out ERR_NONFATAL status bit clearing
PCI/AER: Clear only ERR_NONFATAL bits during non-fatal recovery
PCI/AER: Clear only ERR_FATAL status bits during fatal recovery
PCI/AER: Honor "pcie_ports=native" even if HEST sets FIRMWARE_FIRST
PCI/AER: Add sysfs attributes for rootport cumulative stats
PCI/AER: Add sysfs attributes to provide AER stats and breakdown
PCI/AER: Define aer_stats structure for AER capable devices
PCI/AER: Move internal declarations to drivers/pci/pci.h
PCI/AER: Adopt lspci names for AER error decoding
PCI/AER: Expose internal API for obtaining AER information
# Conflicts:
# drivers/pci/pci.h
If the platform requests Firmware-First error handling, firmware is
responsible for reading and clearing AER status bits. If OSPM also clears
them, we may miss errors. See ACPI v6.2, sec 18.3.2.5 and 18.4.
This race is mostly of theoretical significance, as it is not easy to
reasonably demonstrate it in testing.
Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
[bhelgaas: add similar guards to pci_cleanup_aer_uncorrect_error_status()
and pci_aer_clear_fatal_status()]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
In commit 27d868b5e6 ("PCI: Set MPS to match upstream bridge"), we made
sure every device's MPS setting matches its upstream bridge, making it more
likely that a hot-added device will work in a system with an optimized MPS
configuration.
Recently I've started encountering systems where the endpoint device's MPSS
capability is less than its Root Port's current MPS value, thus the
endpoint is not capable of matching its upstream bridge's MPS setting (see:
bugzilla via "Link:" below). This leaves the system vulnerable - the
upstream Root Port could respond with larger TLPs than the device can
handle, and the device will consider them to be 'Malformed'.
One could use the "pci=pcie_bus_safe" kernel parameter to work around the
issue, but that forces a user to supply a kernel parameter to get the
system to function reliably and may end up limiting MPS settings of other
unrelated, sub-topologies which could benefit from maintaining their larger
values.
Augment Keith's approach to include tuning down a Root Port's MPS setting
when its hot-added endpoint device is not capable of matching it.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=200527
Signed-off-by: Myron Stowe <myron.stowe@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Jon Mason <jdmason@kudzu.us>
Cc: Keith Busch <keith.busch@intel.com>
Cc: Sinan Kaya <okaya@kernel.org>
Cc: Dongdong Liu <liudongdong3@huawei.com>
PCIe r4.0, sec 9.3.5.4, "Device Control Register", shows both
Max_Payload_Size (MPS) and Max_Read_request_Size (MRRS) to be 'RsvdP' for
VFs. Just prior to the table it states:
"PF and VF functionality is defined in Section 7.5.3.4 except where
noted in Table 9-16. For VF fields marked 'RsvdP', the PF setting
applies to the VF."
All of which implies that with respect to Max_Payload_Size Supported
(MPSS), MPS, and MRRS values, we should not be paying any attention to the
VF's fields, but rather only to the PF's. Only looking at the PF's fields
also logically makes sense as it's the sole physical interface to the PCIe
bus.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=200527
Fixes: 27d868b5e6 ("PCI: Set MPS to match upstream bridge")
Signed-off-by: Myron Stowe <myron.stowe@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: stable@vger.kernel.org # 4.3+
Cc: Keith Busch <keith.busch@intel.com>
Cc: Sinan Kaya <okaya@kernel.org>
Cc: Dongdong Liu <liudongdong3@huawei.com>
Cc: Jon Mason <jdmason@kudzu.us>
When both ends of a PCIe Link are capable of a higher bandwidth than is
currently in use, the Link is said to be "downtrained". A downtrained Link
may indicate hardware or configuration problems in the system, but it's
hard to identify such Links from userspace.
Refactor pcie_print_link_status() so it continues to always print PCIe
bandwidth information, as several NIC drivers desire.
Add a new internal __pcie_print_link_status() to emit a message only when a
device's bandwidth is constrained by the fabric and call it from the PCI
core for all devices, which identifies all downtrained Links. It also
emits messages for a few cases that are technically not downtrained, such
as a x4 device in an open-ended x1 slot.
Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
[bhelgaas: changelog, move __pcie_print_link_status() declaration to
drivers/pci/, rename pcie_check_upstream_link() to
pcie_report_downtraining()]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Several PCI core files include pci-aspm.h even though they don't need
anything provided by that file. Remove the unnecessary includes of it.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Sinan Kaya <okaya@kernel.org>
This part of the iwlwifi driver doesn't need anything provided by
pci-aspm.h, so remove the unnecessary include of it.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Sinan Kaya <okaya@kernel.org>
Acked-by: Luca Coelho <luciano.coelho@intel.com>
The ath9k driver doesn't need anything provided by pci-aspm.h, so remove
the unnecessary include of it.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Sinan Kaya <okaya@kernel.org>
Acked-by: Kalle Valo <kvalo@codeaurora.org>
The sysfs_match_string() helper returns index of the matching string in an
array. Use it in pcie_aspm_set_policy() to simplify the code.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
[bhelgaas: squash sysfs_match_string() fix into original patch for issue
Reported-by: Heiner Kallweit <hkallweit1@gmail.com>]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
PCI_EXP_AER_FLAGS was defined twice (with identical definitions), once
under #ifdef CONFIG_ACPI_APEI, and again at the top level. This looks like
my merge error from these commits:
fd3362cb73 ("PCI/AER: Squash aerdrv_core.c into aerdrv.c")
41cbc9eb1a ("PCI/AER: Squash ecrc.c into aerdrv.c")
Remove the duplicate PCI_EXP_AER_FLAGS definition.
Fixes: 41cbc9eb1a ("PCI/AER: Squash ecrc.c into aerdrv.c")
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Oza Pawandeep <poza@codeaurora.org>
When a PCI device is detected, pdev->is_added is set to 1 and proc and
sysfs entries are created.
When the device is removed, pdev->is_added is checked for one and then
device is detached with clearing of proc and sys entries and at end,
pdev->is_added is set to 0.
is_added and is_busmaster are bit fields in pci_dev structure sharing same
memory location.
A strange issue was observed with multiple removal and rescan of a PCIe
NVMe device using sysfs commands where is_added flag was observed as zero
instead of one while removing device and proc,sys entries are not cleared.
This causes issue in later device addition with warning message
"proc_dir_entry" already registered.
Debugging revealed a race condition between the PCI core setting the
is_added bit in pci_bus_add_device() and the NVMe driver reset work-queue
setting the is_busmaster bit in pci_set_master(). As these fields are not
handled atomically, that clears the is_added bit.
Move the is_added bit to a separate private flag variable and use atomic
functions to set and retrieve the device addition state. This avoids the
race because is_added no longer shares a memory location with is_busmaster.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=200283
Signed-off-by: Hari Vyas <hari.vyas@broadcom.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Lukas Wunner <lukas@wunner.de>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
When an fatal error is received by a non-bridge device, the device is
removed, and pci_stop_and_remove_bus_device() deallocates the device
structure. The freed device structure is used by subsequent code to send
uevents and print messages.
Hold a reference on the device until we're finished using it. This is not
an ideal fix because pcie_do_fatal_recovery() should not use the device at
all after removing it, but that's too big a project for right now.
Fixes: 7e9084b367 ("PCI/AER: Handle ERR_FATAL with removal and re-enumeration of devices")
Signed-off-by: Thomas Tai <thomas.tai@oracle.com>
[bhelgaas: changelog, reduce get/put coverage]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
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 <poza@codeaurora.org>
[bhelgaas: changelog, remove pcie_portdrv_slot_reset() completely]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
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 <poza@codeaurora.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Clear the device status bits while handling both ERR_FATAL and ERR_NONFATAL
cases.
Signed-off-by: Oza Pawandeep <poza@codeaurora.org>
[bhelgaas: rename to pci_aer_clear_device_status(), declare internal to PCI
core instead of exposing it everywhere]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
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 <poza@codeaurora.org>
[bhelgaas: changelog]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
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 <poza@codeaurora.org>
[bhelgaas: split to separate patch]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
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 <poza@codeaurora.org>
[bhelgaas: split to separate patch]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
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 <poza@codeaurora.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Simplify waiting for the contained link to become inactive, removing the
indirection to a unnecessary DPC-specific handler.
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Sinan Kaya <okaya@kernel.org>
Reviewed-by: Oza Pawandeep <poza@codeaurora.org>
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 <keith.busch@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Sinan Kaya <okaya@kernel.org>
Reviewed-by: Oza Pawandeep <poza@codeaurora.org>
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 <keith.busch@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Sinan Kaya <okaya@kernel.org>
Reviewed-by: Oza Pawandeep <poza@codeaurora.org>
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 <keith.busch@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Sinan Kaya <okaya@kernel.org>
Reviewed-by: Oza Pawandeep <poza@codeaurora.org>
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 <keith.busch@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Sinan Kaya <okaya@kernel.org>
Reviewed-by: Oza Pawandeep <poza@codeaurora.org>
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 <mr.nuke.me@gmail.com>
[bhelgaas: return "false" from bool function (from kbuild robot)]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Add sysfs attributes for rootport statistics (that are cumulative of all
the ERR_* messages seen on this PCI hierarchy).
Signed-off-by: Rajat Jain <rajatja@google.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
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 <rajatja@google.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
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 <rajatja@google.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
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 <rajatja@google.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
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 <tbaicar@codeaurora.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Oza Pawandeep <poza@codeaurora.org>
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 <keith.busch@intel.com>
[bhelgaas: move AER declarations from linux/aer.h to drivers/pci/pci.h]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Sinan Kaya <okaya@kernel.org>
Reviewed-by: Oza Pawandeep <poza@codeaurora.org>
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 <james.puthukattukaran@oracle.com>
[bhelgaas: changelog, clean up whitespace, fold in unused variable fix
from Anders Roxell <anders.roxell@linaro.org>]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
commit ef1433f717 ("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: ef1433f717 ("PCI: endpoint: Create configfs entry for each
pci_epf_device_id table entry")
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
[lorenzo.pieralisi: updated commit log]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Commit de0aa7b2f9 ("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 f71b74bca6 ("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 de0aa7b2f9: 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: de0aa7b2f9 ("PCI: hv: Fix 2 hang issues in hv_compose_msi_msg()")
Signed-off-by: Dexuan Cui <decui@microsoft.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Cc: stable@vger.kernel.org
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: K. Y. Srinivasan <kys@microsoft.com>
Before 8d85a7a4f2 ("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 8d85a7a4f2, 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 8d85a7a4f2, 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: 8d85a7a4f2 ("PCI/IOV: Allow PF drivers to limit total_VFs to 0")
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
[bhelgaas: changelog]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
