Remove variables and assignments that are never used.
Found by Krzysztof using cppcheck, e.g.,
$ cppcheck --enable=all --force
uselessAssignmentPtrArg drivers/pci/proc.c:102 Assignment of function parameter has no effect outside the function. Did you forget dereferencing it?
unreadVariable drivers/pci/setup-bus.c:1528 Variable 'old_flags' is assigned a value that is never used.
Reported-by: Krzysztof Wilczyński <kw@linux.com>
Link: https://lore.kernel.org/r/20220313192933.434746-2-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
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Merge tag 'pci-v5.16-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci
Pull pci updates from Bjorn Helgaas:
"Enumeration:
- Conserve IRQs by setting up portdrv IRQs only when there are users
(Jan Kiszka)
- Rework and simplify _OSC negotiation for control of PCIe features
(Joerg Roedel)
- Remove struct pci_dev.driver pointer since it's redundant with the
struct device.driver pointer (Uwe Kleine-König)
Resource management:
- Coalesce contiguous host bridge apertures from _CRS to accommodate
BARs that cover more than one aperture (Kai-Heng Feng)
Sysfs:
- Check CAP_SYS_ADMIN before parsing user input (Krzysztof
Wilczyński)
- Return -EINVAL consistently from "store" functions (Krzysztof
Wilczyński)
- Use sysfs_emit() in endpoint "show" functions to avoid buffer
overruns (Kunihiko Hayashi)
PCIe native device hotplug:
- Ignore Link Down/Up caused by resets during error recovery so
endpoint drivers can remain bound to the device (Lukas Wunner)
Virtualization:
- Avoid bus resets on Atheros QCA6174, where they hang the device
(Ingmar Klein)
- Work around Pericom PI7C9X2G switch packet drop erratum by using
store and forward mode instead of cut-through (Nathan Rossi)
- Avoid trying to enable AtomicOps on VFs; the PF setting applies to
all VFs (Selvin Xavier)
MSI:
- Document that /sys/bus/pci/devices/.../irq contains the legacy INTx
interrupt or the IRQ of the first MSI (not MSI-X) vector (Barry
Song)
VPD:
- Add pci_read_vpd_any() and pci_write_vpd_any() to access anywhere
in the possible VPD space; use these to simplify the cxgb3 driver
(Heiner Kallweit)
Peer-to-peer DMA:
- Add (not subtract) the bus offset when calculating DMA address
(Wang Lu)
ASPM:
- Re-enable LTR at Downstream Ports so they don't report Unsupported
Requests when reset or hot-added devices send LTR messages
(Mingchuang Qiao)
Apple PCIe controller driver:
- Add driver for Apple M1 PCIe controller (Alyssa Rosenzweig, Marc
Zyngier)
Cadence PCIe controller driver:
- Return success when probe succeeds instead of falling into error
path (Li Chen)
HiSilicon Kirin PCIe controller driver:
- Reorganize PHY logic and add support for external PHY drivers
(Mauro Carvalho Chehab)
- Support PERST# GPIOs for HiKey970 external PEX 8606 bridge (Mauro
Carvalho Chehab)
- Add Kirin 970 support (Mauro Carvalho Chehab)
- Make driver removable (Mauro Carvalho Chehab)
Intel VMD host bridge driver:
- If IOMMU supports interrupt remapping, leave VMD MSI-X remapping
enabled (Adrian Huang)
- Number each controller so we can tell them apart in
/proc/interrupts (Chunguang Xu)
- Avoid building on UML because VMD depends on x86 bare metal APIs
(Johannes Berg)
Marvell Aardvark PCIe controller driver:
- Define macros for PCI_EXP_DEVCTL_PAYLOAD_* (Pali Rohár)
- Set Max Payload Size to 512 bytes per Marvell spec (Pali Rohár)
- Downgrade PIO Response Status messages to debug level (Marek Behún)
- Preserve CRS SV (Config Request Retry Software Visibility) bit in
emulated Root Control register (Pali Rohár)
- Fix issue in configuring reference clock (Pali Rohár)
- Don't clear status bits for masked interrupts (Pali Rohár)
- Don't mask unused interrupts (Pali Rohár)
- Avoid code repetition in advk_pcie_rd_conf() (Marek Behún)
- Retry config accesses on CRS response (Pali Rohár)
- Simplify emulated Root Capabilities initialization (Pali Rohár)
- Fix several link training issues (Pali Rohár)
- Fix link-up checking via LTSSM (Pali Rohár)
- Fix reporting of Data Link Layer Link Active (Pali Rohár)
- Fix emulation of W1C bits (Marek Behún)
- Fix MSI domain .alloc() method to return zero on success (Marek
Behún)
- Read entire 16-bit MSI vector in MSI handler, not just low 8 bits
(Marek Behún)
- Clear Root Port I/O Space, Memory Space, and Bus Master Enable bits
at startup; PCI core will set those as necessary (Pali Rohár)
- When operating as a Root Port, set class code to "PCI Bridge"
instead of the default "Mass Storage Controller" (Pali Rohár)
- Add emulation for PCI_BRIDGE_CTL_BUS_RESET since aardvark doesn't
implement this per spec (Pali Rohár)
- Add emulation of option ROM BAR since aardvark doesn't implement
this per spec (Pali Rohár)
MediaTek MT7621 PCIe controller driver:
- Add MediaTek MT7621 PCIe host controller driver and DT binding
(Sergio Paracuellos)
Qualcomm PCIe controller driver:
- Add SC8180x compatible string (Bjorn Andersson)
- Add endpoint controller driver and DT binding (Manivannan
Sadhasivam)
- Restructure to use of_device_get_match_data() (Prasad Malisetty)
- Add SC7280-specific pcie_1_pipe_clk_src handling (Prasad Malisetty)
Renesas R-Car PCIe controller driver:
- Remove unnecessary includes (Geert Uytterhoeven)
Rockchip DesignWare PCIe controller driver:
- Add DT binding (Simon Xue)
Socionext UniPhier Pro5 controller driver:
- Serialize INTx masking/unmasking (Kunihiko Hayashi)
Synopsys DesignWare PCIe controller driver:
- Run dwc .host_init() method before registering MSI interrupt
handler so we can deal with pending interrupts left by bootloader
(Bjorn Andersson)
- Clean up Kconfig dependencies (Andy Shevchenko)
- Export symbols to allow more modular drivers (Luca Ceresoli)
TI DRA7xx PCIe controller driver:
- Allow host and endpoint drivers to be modules (Luca Ceresoli)
- Enable external clock if present (Luca Ceresoli)
TI J721E PCIe driver:
- Disable PHY when probe fails after initializing it (Christophe
JAILLET)
MicroSemi Switchtec management driver:
- Return error to application when command execution fails because an
out-of-band reset has cleared the device BARs, Memory Space Enable,
etc (Kelvin Cao)
- Fix MRPC error status handling issue (Kelvin Cao)
- Mask out other bits when reading of management VEP instance ID
(Kelvin Cao)
- Return EOPNOTSUPP instead of ENOTSUPP from sysfs show functions
(Kelvin Cao)
- Add check of event support (Logan Gunthorpe)
Miscellaneous:
- Remove unused pci_pool wrappers, which have been replaced by
dma_pool (Cai Huoqing)
- Use 'unsigned int' instead of bare 'unsigned' (Krzysztof
Wilczyński)
- Use kstrtobool() directly, sans strtobool() wrapper (Krzysztof
Wilczyński)
- Fix some sscanf(), sprintf() format mismatches (Krzysztof
Wilczyński)
- Update PCI subsystem information in MAINTAINERS (Krzysztof
Wilczyński)
- Correct some misspellings (Krzysztof Wilczyński)"
* tag 'pci-v5.16-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (137 commits)
PCI: Add ACS quirk for Pericom PI7C9X2G switches
PCI: apple: Configure RID to SID mapper on device addition
iommu/dart: Exclude MSI doorbell from PCIe device IOVA range
PCI: apple: Implement MSI support
PCI: apple: Add INTx and per-port interrupt support
PCI: kirin: Allow removing the driver
PCI: kirin: De-init the dwc driver
PCI: kirin: Disable clkreq during poweroff sequence
PCI: kirin: Move the power-off code to a common routine
PCI: kirin: Add power_off support for Kirin 960 PHY
PCI: kirin: Allow building it as a module
PCI: kirin: Add MODULE_* macros
PCI: kirin: Add Kirin 970 compatible
PCI: kirin: Support PERST# GPIOs for HiKey970 external PEX 8606 bridge
PCI: apple: Set up reference clocks when probing
PCI: apple: Add initial hardware bring-up
PCI: of: Allow matching of an interrupt-map local to a PCI device
of/irq: Allow matching of an interrupt-map local to an interrupt controller
irqdomain: Make of_phandle_args_to_fwspec() generally available
PCI: Do not enable AtomicOps on VFs
...
- Check for CAP_SYS_ADMIN before validating sysfs user input, not after
(Krzysztof Wilczyński)
- Always return -EINVAL from sysfs "store" functions for invalid user input
instead of -EINVAL sometimes and -ERANGE others (Krzysztof Wilczyński)
- Use kstrtobool() directly instead of the strtobool() wrapper (Krzysztof
Wilczyński)
* pci/sysfs:
PCI: Use kstrtobool() directly, sans strtobool() wrapper
PCI/sysfs: Return -EINVAL consistently from "store" functions
PCI/sysfs: Check CAP_SYS_ADMIN before parsing user input
# Conflicts:
# drivers/pci/iov.c
The sysfs "irq" file contains the legacy INTx IRQ. Or, if the device has
MSI enabled, it contains the first MSI IRQ instead.
Previously this file showed the pci_dev.irq value directly. But we'd
prefer to use pci_dev.irq only for the INTx IRQ and decouple that from any
MSI or MSI-X IRQs.
If the device has MSI enabled, explicitly look up and show the first MSI
IRQ in the sysfs "irq" file. Otherwise, show the INTx IRQ.
This removes the requirement that msi_capability_init() set pci_dev.irq to
the first MSI IRQ when enabling MSI and pci_msi_shutdown() restore the INTx
IRQ when disabling MSI.
[bhelgaas: commit log]
Link: https://lore.kernel.org/r/20210825102636.52757-3-21cnbao@gmail.com
Signed-off-by: Barry Song <song.bao.hua@hisilicon.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Use the proper macro instead of hard-coded (-1) value.
Suggested-by: Krzysztof Wilczyński <kw@linux.com>
Reviewed-by: Krzysztof Wilczyński <kw@linux.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Link: https://lore.kernel.org/r/20211004133453.18881-2-mgurtovoy@nvidia.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Most of the "store" functions that handle userspace input via sysfs return
-EINVAL should the value fail validation and/or type conversion. This
error code is a clear message to userspace that the value is not a valid
input.
However, some of the "show" functions return input parsing error codes
as-is, which may be either -EINVAL or -ERANGE. The former would often be
from kstrtobool(), and the latter typically from other kstr*() functions
such as kstrtou8(), kstrtou32(), kstrtoint(), etc.
-EINVAL is commonly returned as the error code to indicate that the value
provided is invalid, but -ERANGE is not very useful in userspace.
Therefore, normalize the return error code to be -EINVAL for when the
validation and/or type conversion fails.
Link: https://lore.kernel.org/r/20210915230127.2495723-2-kw@linux.com
Signed-off-by: Krzysztof Wilczyński <kw@linux.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Check if the "CAP_SYS_ADMIN" capability flag is set before parsing user
input as it makes more sense to first check whether the current user
actually has the right permissions before accepting any input from such
user.
This will also make order in which enable_store() and msi_bus_store()
perform the "CAP_SYS_ADMIN" capability check consistent with other
PCI-related sysfs objects that first verify whether user has this
capability set.
Link: https://lore.kernel.org/r/20210915230127.2495723-1-kw@linux.com
Signed-off-by: Krzysztof Wilczyński <kw@linux.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Here is the big set of driver core patches for 5.15-rc1.
These do change a number of different things across different
subsystems, and because of that, there were 2 stable tags created that
might have already come into your tree from different pulls that did the
following
- changed the bus remove callback to return void
- sysfs iomem_get_mapping rework
The latter one will cause a tiny merge issue with your tree, as there
was a last-minute fix for this in 5.14 in your tree, but the fixup
should be "obvious". If you want me to provide a fixed merge for this,
please let me know.
Other than those two things, there's only a few small things in here:
- kernfs performance improvements for huge numbers of sysfs
users at once
- tiny api cleanups
- other minor changes
All of these have been in linux-next for a while with no reported
problems, other than the before-mentioned merge issue.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-5.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core updates from Greg KH:
"Here is the big set of driver core patches for 5.15-rc1.
These do change a number of different things across different
subsystems, and because of that, there were 2 stable tags created that
might have already come into your tree from different pulls that did
the following
- changed the bus remove callback to return void
- sysfs iomem_get_mapping rework
Other than those two things, there's only a few small things in here:
- kernfs performance improvements for huge numbers of sysfs users at
once
- tiny api cleanups
- other minor changes
All of these have been in linux-next for a while with no reported
problems, other than the before-mentioned merge issue"
* tag 'driver-core-5.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (33 commits)
MAINTAINERS: Add dri-devel for component.[hc]
driver core: platform: Remove platform_device_add_properties()
ARM: tegra: paz00: Handle device properties with software node API
bitmap: extend comment to bitmap_print_bitmask/list_to_buf
drivers/base/node.c: use bin_attribute to break the size limitation of cpumap ABI
topology: use bin_attribute to break the size limitation of cpumap ABI
lib: test_bitmap: add bitmap_print_bitmask/list_to_buf test cases
cpumask: introduce cpumap_print_list/bitmask_to_buf to support large bitmask and list
sysfs: Rename struct bin_attribute member to f_mapping
sysfs: Invoke iomem_get_mapping() from the sysfs open callback
debugfs: Return error during {full/open}_proxy_open() on rmmod
zorro: Drop useless (and hardly used) .driver member in struct zorro_dev
zorro: Simplify remove callback
sh: superhyway: Simplify check in remove callback
nubus: Simplify check in remove callback
nubus: Make struct nubus_driver::remove return void
kernfs: dont call d_splice_alias() under kernfs node lock
kernfs: use i_lock to protect concurrent inode updates
kernfs: switch kernfs to use an rwsem
kernfs: use VFS negative dentry caching
...
Two legacy PCI sysfs objects "legacy_io" and "legacy_mem" were updated
to use an unified address space in the commit 636b21b501 ("PCI: Revoke
mappings like devmem"). This allows for revocations to be managed from
a single place when drivers want to take over and mmap() a /dev/mem
range.
Following the update, both of the sysfs objects should leverage the
iomem_get_mapping() function to get an appropriate address range, but
only the "legacy_io" has been correctly updated - the second attribute
seems to be using a wrong variable to pass the iomem_get_mapping()
function to.
Thus, correct the variable name used so that the "legacy_mem" sysfs
object would also correctly call the iomem_get_mapping() function.
Fixes: 636b21b501 ("PCI: Revoke mappings like devmem")
Link: https://lore.kernel.org/r/20210812132144.791268-1-kw@linux.com
Signed-off-by: Krzysztof Wilczyński <kw@linux.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Add "reset_method" sysfs attribute to enable user to query and set
preferred device reset methods and their ordering.
[bhelgaas: on invalid sysfs input, return error and preserve previous
config, as in earlier patch versions]
Co-developed-by: Alex Williamson <alex.williamson@redhat.com>
Link: https://lore.kernel.org/r/20210817180500.1253-6-ameynarkhede03@gmail.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Amey Narkhede <ameynarkhede03@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Raphael Norwitz <raphael.norwitz@nutanix.com>
"reset_fn" indicates whether the device supports any reset mechanism.
Remove the use of reset_fn in favor of the reset_methods array that tracks
supported reset mechanisms of a device and their ordering.
The octeon driver incorrectly used reset_fn to detect whether the device
supports FLR or not. Use pcie_reset_flr() to probe whether it supports FLR.
Co-developed-by: Alex Williamson <alex.williamson@redhat.com>
Link: https://lore.kernel.org/r/20210817180500.1253-5-ameynarkhede03@gmail.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Amey Narkhede <ameynarkhede03@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Raphael Norwitz <raphael.norwitz@nutanix.com>
There are two users of iomem_get_mapping(), the struct file and struct
bin_attribute. The former has a member called "f_mapping" and the
latter has a member called "mapping", and both are poniters to struct
address_space.
Rename struct bin_attribute member to "f_mapping" to keep both meaning
and the usage consistent with other users of iomem_get_mapping().
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Krzysztof Wilczyński <kw@linux.com>
Link: https://lore.kernel.org/r/20210729233235.1508920-3-kw@linux.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Defer invocation of the iomem_get_mapping() to the sysfs open callback
so that it can be executed as needed when the binary sysfs object has
been accessed.
To do that, convert the "mapping" member of the struct bin_attribute
from a pointer to the struct address_space into a function pointer with
a signature that requires the same return type, and then updates the
sysfs_kf_bin_open() to invoke provided function should the function
pointer be valid.
Also, convert every invocation of iomem_get_mapping() into a function
pointer assignment, therefore allowing for the iomem_get_mapping()
invocation to be deferred to when the sysfs open callback runs.
Thus, this change removes the need for the fs_initcalls to complete
before any other sub-system that uses the iomem_get_mapping() would be
able to invoke it safely without leading to a failure and an Oops
related to an invalid iomem_get_mapping() access.
Suggested-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Krzysztof Wilczyński <kw@linux.com>
Link: https://lore.kernel.org/r/20210729233235.1508920-2-kw@linux.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Previously, when the value of the "devspec" sysfs attribute was read from
the user space there was no newline present, and utilities such as "cat"
wouldn't display the result of the read correctly.
Append a newline character in the show() function to match other "devspec"
attributes.
Link: https://lore.kernel.org/r/20210603000112.703037-5-kw@linux.com
Signed-off-by: Krzysztof Wilczyński <kw@linux.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
The sysfs_emit() and sysfs_emit_at() functions were introduced to make it
less ambiguous which function is preferred when writing to the output
buffer in a device attribute's "show" callback [1].
Convert the PCI sysfs object "show" functions from sprintf(), snprintf()
and scnprintf() to sysfs_emit() and sysfs_emit_at() accordingly, as the
latter is aware of the PAGE_SIZE buffer and correctly returns the number of
bytes written into the buffer.
No functional change intended.
[1] Documentation/filesystems/sysfs.rst
[bhelgaas: drop dsm_label_utf16s_to_utf8s(), link speed/width changes]
Link: https://lore.kernel.org/r/20210416205856.3234481-10-kw@linux.com
Signed-off-by: Krzysztof Wilczyński <kw@linux.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
The "label", "index", and "acpi_index" sysfs attributes show firmware label
information about the device. If the ACPI Device Name _DSM is implemented
for the device, we have:
label Device name (optional, may be null)
acpi_index Instance number (unique under \_SB scope)
When there is no ACPI _DSM and SMBIOS provides an Onboard Devices structure
for the device, we have:
label Reference Designation, e.g., a silkscreen label
index Device Type Instance
Previously these attributes were dynamically created either by
pci_bus_add_device() or the pci_sysfs_init() initcall, but since they don't
need to be created or removed dynamically, we can use a static attribute so
the device model takes care of addition and removal automatically.
Convert "label", "index", and "acpi_index" to static attributes.
Presence of the ACPI _DSM (device_has_acpi_name()) determines whether the
ACPI information (label, acpi_index) or the SMBIOS information (label,
index) is visible.
[bhelgaas: commit log, split to separate patch, add "pci_dev_" prefix]
Suggested-by: Oliver O'Halloran <oohall@gmail.com>
Link: https://lore.kernel.org/r/20210416205856.3234481-6-kw@linux.com
Signed-off-by: Krzysztof Wilczyński <kw@linux.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
The "vpd" sysfs attribute allows access to Vital Product Data (VPD).
Previously it was dynamically created either by pci_bus_add_device() or the
pci_sysfs_init() initcall, but since it doesn't need to be created or
removed dynamically, we can use a static attribute so the device model
takes care of addition and removal automatically.
Convert "vpd" to a static attribute and use the .is_bin_visible() callback
to check whether the device supports VPD.
Remove pcie_vpd_create_sysfs_dev_files(),
pcie_vpd_remove_sysfs_dev_files(), pci_create_capabilities_sysfs(), and
pci_create_capabilities_sysfs(), which are no longer needed.
[bhelgaas: This is substantially the same as the earlier patch from Heiner
Kallweit <hkallweit1@gmail.com>. I included Krzysztof's change here so all
the "convert to static attribute" changes are together.]
[bhelgaas: rename to vpd_read()/vpd_write() and pci_dev_vpd_attr_group]
Suggested-by: Oliver O'Halloran <oohall@gmail.com>
Based-on: https://lore.kernel.org/r/7703024f-8882-9eec-a122-599871728a89@gmail.com
Based-on-patch-by: Heiner Kallweit <hkallweit1@gmail.com>
Link: https://lore.kernel.org/r/20210416205856.3234481-5-kw@linux.com
Signed-off-by: Krzysztof Wilczyński <kw@linux.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
The "reset" sysfs attribute allows for resetting a PCI function.
Previously it was dynamically created either by pci_bus_add_device() or
the pci_sysfs_init() initcall, but since it doesn't need to be created or
removed dynamically, we can use a static attribute so the device model
takes care of addition and removal automatically.
Convert "reset" to a static attribute and use the .is_visible() callback to
check whether the device supports reset.
Clear reset_fn in pci_stop_dev() instead of pci_remove_capabilities_sysfs()
since we no longer explicitly remove the "reset" sysfs file.
[bhelgaas: commit log]
Suggested-by: Oliver O'Halloran <oohall@gmail.com>
Link: https://lore.kernel.org/r/20210416205856.3234481-4-kw@linux.com
Signed-off-by: Krzysztof Wilczyński <kw@linux.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
The "rom" sysfs attribute allows access to the PCI Option ROM. Previously
it was dynamically created either by pci_bus_add_device() or the
pci_sysfs_init() initcall, but since it doesn't need to be created or
removed dynamically, we can use a static attribute so the device model
takes care of addition and removal automatically.
Convert "rom" to a static attribute and use the .is_bin_visible() callback
to set the correct object size based on the ROM size.
Remove "rom_attr" from the struct pci_dev since it is no longer needed.
This attribute was added in the pre-git era by https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git/commit/drivers/pci/pci-sysfs.c?id=f6d553444da2
[bhelgaas: commit log]
Suggested-by: Oliver O'Halloran <oohall@gmail.com>
Link: https://lore.kernel.org/r/20210416205856.3234481-3-kw@linux.com
Signed-off-by: Krzysztof Wilczyński <kw@linux.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
The "config" sysfs attribute allows access to either the legacy (PCI and
PCI-X Mode 1) or the extended (PCI-X Mode 2 and PCIe) device configuration
space. Previously it was dynamically created either when a device was
added (for hot-added devices) or via a late_initcall (for devices present
at boot):
pci_bus_add_devices
pci_bus_add_device
pci_create_sysfs_dev_files
if (!sysfs_initialized)
return
sysfs_create_bin_file # for hot-added devices
pci_sysfs_init # late_initcall
sysfs_initialized = 1
for_each_pci_dev(pdev)
pci_create_sysfs_dev_files(pdev) # for devices present at boot
And dynamically removed when the PCI device is stopped and removed:
pci_stop_bus_device
pci_stop_dev
pci_remove_sysfs_dev_files
sysfs_remove_bin_file
This attribute does not need to be created or removed dynamically, so we
can use a static attribute so the device model takes care of addition and
removal automatically.
Convert "config" to a static attribute and use the .is_bin_visible()
callback to set the correct object size (either 256 bytes or 4 KiB) at
runtime.
The pci_sysfs_init() scheme was added in the pre-git era by
https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git/commit/drivers/pci/pci-sysfs.c?id=f6d553444da2
[bhelgaas: commit log]
Suggested-by: Oliver O'Halloran <oohall@gmail.com>
Link: https://lore.kernel.org/r/CAOSf1CHss03DBSDO4PmTtMp0tCEu5kScn704ZEwLKGXQzBfqaA@mail.gmail.com
Link: https://lore.kernel.org/r/20210416205856.3234481-2-kw@linux.com
Signed-off-by: Krzysztof Wilczyński <kw@linux.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
A typical cloud provider SR-IOV use case is to create many VFs for use by
guest VMs. The VFs may not be assigned to a VM until a customer requests a
VM of a certain size, e.g., number of CPUs. A VF may need MSI-X vectors
proportional to the number of CPUs in the VM, but there is no standard way
to change the number of MSI-X vectors supported by a VF.
Some Mellanox ConnectX devices support dynamic assignment of MSI-X vectors
to SR-IOV VFs. This can be done by the PF driver after VFs are enabled,
and it can be done without affecting VFs that are already in use. The
hardware supports a limited pool of MSI-X vectors that can be assigned to
the PF or to individual VFs. This is device-specific behavior that
requires support in the PF driver.
Add a read-only "sriov_vf_total_msix" sysfs file for the PF and a writable
"sriov_vf_msix_count" file for each VF. Management software may use these
to learn how many MSI-X vectors are available and to dynamically assign
them to VFs before the VFs are passed through to a VM.
If the PF driver implements the ->sriov_get_vf_total_msix() callback,
"sriov_vf_total_msix" contains the total number of MSI-X vectors available
for distribution among VFs.
If no driver is bound to the VF, writing "N" to "sriov_vf_msix_count" uses
the PF driver ->sriov_set_msix_vec_count() callback to assign "N" MSI-X
vectors to the VF. When a VF driver subsequently reads the MSI-X Message
Control register, it will see the new Table Size "N".
Link: https://lore.kernel.org/linux-pci/20210314124256.70253-2-leon@kernel.org
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Since 3234ac664a ("/dev/mem: Revoke mappings when a driver claims
the region") /dev/kmem zaps PTEs when the kernel requests exclusive
acccess to an iomem region. And with CONFIG_IO_STRICT_DEVMEM, this is
the default for all driver uses.
Except there are two more ways to access PCI BARs: sysfs and proc mmap
support. Let's plug that hole.
For revoke_devmem() to work we need to link our vma into the same
address_space, with consistent vma->vm_pgoff. ->pgoff is already
adjusted, because that's how (io_)remap_pfn_range works, but for the
mapping we need to adjust vma->vm_file->f_mapping. The cleanest way is
to adjust this at at ->open time:
- for sysfs this is easy, now that binary attributes support this. We
just set bin_attr->mapping when mmap is supported
- for procfs it's a bit more tricky, since procfs PCI access has only
one file per device, and access to a specific resource first needs
to be set up with some ioctl calls. But mmap is only supported for
the same resources as sysfs exposes with mmap support, and otherwise
rejected, so we can set the mapping unconditionally at open time
without harm.
A special consideration is for arch_can_pci_mmap_io() - we need to
make sure that the ->f_mapping doesn't alias between ioport and iomem
space. There are only 2 ways in-tree to support mmap of ioports: generic
PCI mmap (ARCH_GENERIC_PCI_MMAP_RESOURCE), and sparc as the single
architecture hand-rolling. Both approaches support ioport mmap through a
special PFN range and not through magic PTE attributes. Aliasing is
therefore not a problem.
The only difference in access checks left is that sysfs PCI mmap does
not check for CAP_RAWIO. I'm not really sure whether that should be
added or not.
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Kees Cook <keescook@chromium.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Jérôme Glisse <jglisse@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-mm@kvack.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-samsung-soc@vger.kernel.org
Cc: linux-media@vger.kernel.org
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: linux-pci@vger.kernel.org
Link: https://patchwork.freedesktop.org/patch/msgid/20210204165831.2703772-3-daniel.vetter@ffwll.ch
We are already doing this for all the regular sysfs files on PCI
devices, but not yet on the legacy io files on the PCI buses. Thus far
no problem, but in the next patch I want to wire up iomem revoke
support. That needs the vfs up and running already to make sure that
iomem_get_mapping() works.
Wire it up exactly like the existing code in
pci_create_sysfs_dev_files(). Note that pci_remove_legacy_files()
doesn't need a check since the one for pci_bus->legacy_io is
sufficient.
An alternative solution would be to implement a callback in sysfs to
set up the address space from iomem_get_mapping() when userspace calls
mmap(). This also works, but Greg didn't really like that just to work
around an ordering issue when the kernel loads initially.
v2: Improve commit message (Bjorn)
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Kees Cook <keescook@chromium.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Jérôme Glisse <jglisse@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-mm@kvack.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-samsung-soc@vger.kernel.org
Cc: linux-media@vger.kernel.org
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: linux-pci@vger.kernel.org
Link: https://patchwork.freedesktop.org/patch/msgid/20210205133632.2827730-1-daniel.vetter@ffwll.ch
While PCI power states D0-D3hot can be queried from user-space via lspci,
D3cold cannot. lspci cannot provide an accurate value when the device is
in D3cold as it has to restore the device to D0 before it can access its
power state via the configuration space, leading to it reporting D0 or
another on-state. Thus lspci cannot be used to diagnose power consumption
issues for devices that can enter D3cold or to ensure that devices properly
enter D3cold at all.
Add a new sysfs device attribute for the PCI power state, showing the
current power state as seen by the kernel.
[bhelgaas: drop READ_ONCE(), see discussion at the link]
Link: https://lore.kernel.org/r/20201102141520.831630-1-luzmaximilian@gmail.com
Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
- Remove unnecessary #includes (Gustavo Pimentel)
- Fix intel_mid_pci.c build error when !CONFIG_ACPI (Randy Dunlap)
- Use scnprintf(), not snprintf(), in sysfs "show" functions (Krzysztof
Wilczyński)
- Simplify pci-pf-stub by using module_pci_driver() (Liu Shixin)
- Print IRQ used by Link Bandwidth Notification (Dongdong Liu)
- Update sysfs mmap-related #ifdef comments (Clint Sbisa)
- Simplify pci_dev_reset_slot_function() (Lukas Wunner)
- Use "NULL" instead of "0" to fix sparse warnings (Gustavo Pimentel)
- Simplify bool comparisons (Krzysztof Wilczyński)
- Drop double zeroing for P2PDMA sg_init_table() (Julia Lawall)
* pci/misc:
PCI: v3-semi: Remove unneeded break
PCI/P2PDMA: Drop double zeroing for sg_init_table()
PCI: Simplify bool comparisons
PCI: endpoint: Use "NULL" instead of "0" as a NULL pointer
PCI: Simplify pci_dev_reset_slot_function()
PCI: Update mmap-related #ifdef comments
PCI/LINK: Print IRQ number used by port
PCI/IOV: Simplify pci-pf-stub with module_pci_driver()
PCI: Use scnprintf(), not snprintf(), in sysfs "show" functions
x86/PCI: Fix intel_mid_pci.c build error when ACPI is not enabled
PCI: Remove unnecessary header includes
f719582435 ("PCI: Add pci_mmap_resource_range() and use it for ARM64")
changed the #ifdef condition around pci_create_resource_files(),
pci_remove_resource_files(), and related functions, but did not update
comments at the #else and #ifdef.
Update the comments to match the #ifdef.
[bhelgaas: commit log, drop #endif comment since it's close to the #else]
Link: https://lore.kernel.org/r/20200821155121.nzxjeeoze4h5pone@amazon.com
Signed-off-by: Clint Sbisa <csbisa@amazon.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
The PCI sysfs "config" file allows large reads, and the resulting PCI
config reads can take several milliseconds to complete. Testing with the
cyclictest [1] benchmark showed 5ms+ latencies.
Add a schedule point in pci_read_config() to reduce the maximum latency.
[1] https://git.kernel.org/pub/scm/linux/kernel/git/clrkwllms/rt-tests.git/
[bhelgaas: commit log]
Link: https://lore.kernel.org/r/20200824052025.48362-1-benbjiang@tencent.com
Reported-by: Bin Lai <robinlai@tencent.com>
Signed-off-by: Jiang Biao <benbjiang@tencent.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
- Move _HPX type array from stack to static data (Colin Ian King)
- Avoid an ASMedia XHCI USB PME# defect; apparently it doesn't assert
PME# when USB3.0 devices are hotplugged in D0 (Kai-Heng Feng)
- Revert sysfs "rescan" file renames that broke an application (Kelsey
Skunberg)
* pci/misc:
PCI: sysfs: Revert "rescan" file renames
PCI: Avoid ASMedia XHCI USB PME# from D0 defect
PCI/ACPI: Move pcie_to_hpx3_type[] from stack to static data
We changed these sysfs filenames:
.../pci_bus/<domain:bus>/rescan -> .../pci_bus/<domain:bus>/bus_rescan
.../<domain🚌dev.fn>/rescan -> .../<domain🚌dev.fn>/dev_rescan
and Ruslan reported [1] that this broke a userspace application.
Revert these name changes so both files are named "rescan" again.
Note that we have to use __ATTR() to assign custom C symbols, i.e.,
"struct device_attribute <symbol>".
[1] https://lore.kernel.org/r/CAB=otbSYozS-ZfxB0nCiNnxcbqxwrHOSYxJJtDKa63KzXbXgpw@mail.gmail.com
[bhelgaas: commit log, use __ATTR() both places so we don't have to rename
the attributes]
Fixes: 8bdfa145f5 ("PCI: sysfs: Define device attributes with DEVICE_ATTR*()")
Fixes: 4e2b79436e ("PCI: sysfs: Change DEVICE_ATTR() to DEVICE_ATTR_WO()")
Link: https://lore.kernel.org/r/20200325151708.32612-1-skunberg.kelsey@gmail.com
Signed-off-by: Kelsey Skunberg <kelsey.skunberg@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: stable@vger.kernel.org # v5.4+
Previously some PCI speed strings came from pci_speed_string(), some came
from the PCIe-specific PCIE_SPEED2STR(), and some came from a PCIe-specific
switch statement. These methods were inconsistent:
pci_speed_string() PCIE_SPEED2STR() switch
------------------ ---------------- ------
33 MHz PCI
...
2.5 GT/s PCIe 2.5 GT/s 2.5 GT/s
5.0 GT/s PCIe 5 GT/s 5 GT/s
8.0 GT/s PCIe 8 GT/s 8 GT/s
16.0 GT/s PCIe 16 GT/s 16 GT/s
32.0 GT/s PCIe 32 GT/s 32 GT/s
Standardize on pci_speed_string() as the single source of these strings.
Note that this adds ".0" and "PCIe" to some messages, including sysfs
"max_link_speed" files, a brcmstb "link up" message, and the link status
dmesg logging, e.g.,
nvme 0000:01:00.0: 16.000 Gb/s available PCIe bandwidth, limited by 5.0 GT/s PCIe x4 link at 0000:00:01.1 (capable of 31.504 Gb/s with 8.0 GT/s PCIe x4 link)
I think it's better to standardize on a single version of the speed text.
Previously we had strings like this:
/sys/bus/pci/slots/0/cur_bus_speed: 8.0 GT/s PCIe
/sys/bus/pci/slots/0/max_bus_speed: 8.0 GT/s PCIe
/sys/devices/pci0000:00/0000:00:1c.0/current_link_speed: 8 GT/s
/sys/devices/pci0000:00/0000:00:1c.0/max_link_speed: 8 GT/s
This changes the latter two to match the slots files:
/sys/devices/pci0000:00/0000:00:1c.0/current_link_speed: 8.0 GT/s PCIe
/sys/devices/pci0000:00/0000:00:1c.0/max_link_speed: 8.0 GT/s PCIe
Based-on-patch by: Yicong Yang <yangyicong@hisilicon.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
- Protect pci_reassign_bridge_resources() against concurrent
addition/removal (Benjamin Herrenschmidt)
- Fix bridge dma_ranges resource list cleanup (Rob Herring)
- Add PCI_STD_NUM_BARS for the number of standard BARs (Denis Efremov)
- Add "pci=hpmmiosize" and "pci=hpmmioprefsize" parameters to control the
MMIO and prefetchable MMIO window sizes of hotplug bridges
independently (Nicholas Johnson)
- Fix MMIO/MMIO_PREF window assignment that assigned more space than
desired (Nicholas Johnson)
- Only enforce bus numbers from bridge EA if the bridge has EA devices
downstream (Subbaraya Sundeep)
* pci/resource:
PCI: Do not use bus number zero from EA capability
PCI: Avoid double hpmemsize MMIO window assignment
PCI: Add "pci=hpmmiosize" and "pci=hpmmioprefsize" parameters
PCI: Add PCI_STD_NUM_BARS for the number of standard BARs
PCI: Fix missing bridge dma_ranges resource list cleanup
PCI: Protect pci_reassign_bridge_resources() against concurrent addition/removal
Previously, CONFIG_PCIEASPM_DEBUG enabled "link_state" and "clk_ctl" sysfs
files that controlled ASPM. We believe these files were rarely if ever
used.
We recently added sysfs ASPM controls that are always present, so the debug
code is no longer needed. Removing this debug code has been discussed for
quite some time, see e.g. [0].
Remove PCIEASPM_DEBUG and the related code.
[0] https://lore.kernel.org/lkml/20180727202619.GD173328@bhelgaas-glaptop.roam.corp.google.com/
Link: https://lore.kernel.org/r/ec935d8e-c084-3938-f1d1-748617596b25@gmail.com
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Add sysfs attributes to Endpoints and other Upstream Ports to control ASPM,
Clock PM, and L1 PM Substates. The new attributes are:
/sys/devices/pci*/.../link/clkpm
/sys/devices/pci*/.../link/l0s_aspm
/sys/devices/pci*/.../link/l1_aspm
/sys/devices/pci*/.../link/l1_1_aspm
/sys/devices/pci*/.../link/l1_2_aspm
/sys/devices/pci*/.../link/l1_1_pcipm
/sys/devices/pci*/.../link/l1_2_pcipm
An attribute is only visible if both ends of the Link leading to the device
support the state. Writing y/1/on to the file enables the state; n/0/off
disables it.
These attributes can be used to tune the power/performance tradeoff for
individual devices.
[bhelgaas: commit log, rename directory to "link"]
Link: https://lore.kernel.org/r/b1c83f8a-9bf6-eac5-82d0-cf5b90128fbf@gmail.com
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
56c1af4606 ("PCI: Add sysfs max_link_speed/width,
current_link_speed/width, etc") added the following objects, but they are
unused, so remove them:
pci_bridge_group
pci_bridge_groups
pcie_dev_group
pcie_dev_groups
This fixes the following warnings from sparse:
drivers/pci/pci-sysfs.c:1546:30: warning: symbol 'pci_bridge_groups' was not declared. Should it be static?
drivers/pci/pci-sysfs.c:1555:30: warning: symbol 'pcie_dev_groups' was not declared. Should it be static?
Link: https://lore.kernel.org/r/20191016080324.12864-1-ben.dooks@codethink.co.uk
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Code that iterates over all standard PCI BARs typically uses
PCI_STD_RESOURCE_END. However, that requires the unusual test
"i <= PCI_STD_RESOURCE_END" rather than something the typical
"i < PCI_STD_NUM_BARS".
Add a definition for PCI_STD_NUM_BARS and change loops to use the more
idiomatic C style to help avoid fencepost errors.
Link: https://lore.kernel.org/r/20190927234026.23342-1-efremov@linux.com
Link: https://lore.kernel.org/r/20190927234308.23935-1-efremov@linux.com
Link: https://lore.kernel.org/r/20190916204158.6889-3-efremov@linux.com
Signed-off-by: Denis Efremov <efremov@linux.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Sebastian Ott <sebott@linux.ibm.com> # arch/s390/
Acked-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> # video/fbdev/
Acked-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com> # pci/controller/dwc/
Acked-by: Jack Wang <jinpu.wang@cloud.ionos.com> # scsi/pm8001/
Acked-by: Martin K. Petersen <martin.petersen@oracle.com> # scsi/pm8001/
Acked-by: Ulf Hansson <ulf.hansson@linaro.org> # memstick/
Pull kernel lockdown mode from James Morris:
"This is the latest iteration of the kernel lockdown patchset, from
Matthew Garrett, David Howells and others.
From the original description:
This patchset introduces an optional kernel lockdown feature,
intended to strengthen the boundary between UID 0 and the kernel.
When enabled, various pieces of kernel functionality are restricted.
Applications that rely on low-level access to either hardware or the
kernel may cease working as a result - therefore this should not be
enabled without appropriate evaluation beforehand.
The majority of mainstream distributions have been carrying variants
of this patchset for many years now, so there's value in providing a
doesn't meet every distribution requirement, but gets us much closer
to not requiring external patches.
There are two major changes since this was last proposed for mainline:
- Separating lockdown from EFI secure boot. Background discussion is
covered here: https://lwn.net/Articles/751061/
- Implementation as an LSM, with a default stackable lockdown LSM
module. This allows the lockdown feature to be policy-driven,
rather than encoding an implicit policy within the mechanism.
The new locked_down LSM hook is provided to allow LSMs to make a
policy decision around whether kernel functionality that would allow
tampering with or examining the runtime state of the kernel should be
permitted.
The included lockdown LSM provides an implementation with a simple
policy intended for general purpose use. This policy provides a coarse
level of granularity, controllable via the kernel command line:
lockdown={integrity|confidentiality}
Enable the kernel lockdown feature. If set to integrity, kernel features
that allow userland to modify the running kernel are disabled. If set to
confidentiality, kernel features that allow userland to extract
confidential information from the kernel are also disabled.
This may also be controlled via /sys/kernel/security/lockdown and
overriden by kernel configuration.
New or existing LSMs may implement finer-grained controls of the
lockdown features. Refer to the lockdown_reason documentation in
include/linux/security.h for details.
The lockdown feature has had signficant design feedback and review
across many subsystems. This code has been in linux-next for some
weeks, with a few fixes applied along the way.
Stephen Rothwell noted that commit 9d1f8be5cf ("bpf: Restrict bpf
when kernel lockdown is in confidentiality mode") is missing a
Signed-off-by from its author. Matthew responded that he is providing
this under category (c) of the DCO"
* 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (31 commits)
kexec: Fix file verification on S390
security: constify some arrays in lockdown LSM
lockdown: Print current->comm in restriction messages
efi: Restrict efivar_ssdt_load when the kernel is locked down
tracefs: Restrict tracefs when the kernel is locked down
debugfs: Restrict debugfs when the kernel is locked down
kexec: Allow kexec_file() with appropriate IMA policy when locked down
lockdown: Lock down perf when in confidentiality mode
bpf: Restrict bpf when kernel lockdown is in confidentiality mode
lockdown: Lock down tracing and perf kprobes when in confidentiality mode
lockdown: Lock down /proc/kcore
x86/mmiotrace: Lock down the testmmiotrace module
lockdown: Lock down module params that specify hardware parameters (eg. ioport)
lockdown: Lock down TIOCSSERIAL
lockdown: Prohibit PCMCIA CIS storage when the kernel is locked down
acpi: Disable ACPI table override if the kernel is locked down
acpi: Ignore acpi_rsdp kernel param when the kernel has been locked down
ACPI: Limit access to custom_method when the kernel is locked down
x86/msr: Restrict MSR access when the kernel is locked down
x86: Lock down IO port access when the kernel is locked down
...
The sysfs SR-IOV functions are only needed when the kernel is built with
SR-IOV support. Rather than put them in pci-sysfs.c under #ifdef
CONFIG_PCI_IOV, move them to iov.c, which is only compiled when
CONFIG_PCI_IOV=y.
Link: https://lore.kernel.org/r/20190813204513.4790-4-skunberg.kelsey@gmail.com
Signed-off-by: Kelsey Skunberg <skunberg.kelsey@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Donald Dutile <ddutile@redhat.com>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
DEVICE_ATTR() should only be used when files have unusual permissions.
Change DEVICE_ATTR() with '0220' write-only permissions to
DEVICE_ATTR_WO(), e.g.,
- static DEVICE_ATTR(_name, (S_IWUSR | S_IWGRP), NULL, _store);
+ static DEVICE_ATTR_WO(_name);
Since _store is no longer passed, make the _name passed by DEVICE_ATTR_WO()
and the related _name##_store() name match with each other, e.g.,
DEVICE_ATTR_WO(bus_rescan) must be able to call bus_rescan_store()
Link: https://lore.kernel.org/r/20190815153352.86143-4-skunberg.kelsey@gmail.com
Signed-off-by: Kelsey Skunberg <skunberg.kelsey@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Donald Dutile <ddutile@redhat.com>
Any hardware that can potentially generate DMA has to be locked down in
order to avoid it being possible for an attacker to modify kernel code,
allowing them to circumvent disabled module loading or module signing.
Default to paranoid - in future we can potentially relax this for
sufficiently IOMMU-isolated devices.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Matthew Garrett <mjg59@google.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
cc: linux-pci@vger.kernel.org
Signed-off-by: James Morris <jmorris@namei.org>
With CONFIG_PROVE_LOCKING=y, using sysfs to remove a bridge with a device
below it causes a lockdep warning, e.g.,
# echo 1 > /sys/class/pci_bus/0000:00/device/0000:00:00.0/remove
============================================
WARNING: possible recursive locking detected
...
pci_bus 0000:01: busn_res: [bus 01] is released
The remove recursively removes the subtree below the bridge. Each call
uses a different lock so there's no deadlock, but the locks were all
created with the same lockdep key so the lockdep checker can't tell them
apart.
Mark the "remove" sysfs attribute with __ATTR_IGNORE_LOCKDEP() as it is
safe to ignore the lockdep check between different "remove" kernfs
instances.
There's discussion about a similar issue in USB at [1], which resulted in
356c05d58a ("sysfs: get rid of some lockdep false positives") and
e9b526fe70 ("i2c: suppress lockdep warning on delete_device"), which do
basically the same thing for USB "remove" and i2c "delete_device" files.
[1] https://lore.kernel.org/r/Pine.LNX.4.44L0.1204251436140.1206-100000@iolanthe.rowland.org
Link: https://lore.kernel.org/r/20190526225151.3865-1-marek.vasut@gmail.com
Signed-off-by: Marek Vasut <marek.vasut+renesas@gmail.com>
[bhelgaas: trim commit log, details at above links]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Phil Edworthy <phil.edworthy@renesas.com>
Cc: Simon Horman <horms+renesas@verge.net.au>
Cc: Tejun Heo <tj@kernel.org>
Cc: Wolfram Sang <wsa@the-dreams.de>
PCIe r5.0, sec 7.5.3.18, defines a new 32.0 GT/s bit in the Supported Link
Speeds Vector of Link Capabilities 2. Decode this new speed. This does
not affect the speed of the link, which should be negotiated automatically
by the hardware; it only adds decoding when showing the speed to the user.
Previously, reading the speed of a link operating at this speed showed
"Unknown speed" instead of "32.0 GT/s".
Link: https://lore.kernel.org/lkml/92365e3caf0fc559f9ab14bcd053bfc92d4f661c.1559664969.git.gustavo.pimentel@synopsys.com
Signed-off-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com>
[bhelgaas: changelog]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Use dev_printk() when possible. This makes messages more consistent with
other device-related messages and, in some cases, adds useful information.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
We are trying to get rid of BUS_ATTR() and the usage of that in
pci-sysfs.c can be trivially converted to use BUS_ATTR_WO(), so use that
instead.
Cc: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Bjorn Helgaas