In hindsight, there were some crucial subtleties overlooked when moving
{of,acpi}_dma_configure() to driver probe time to allow waiting for
IOMMU drivers with -EPROBE_DEFER, and these have become an
ever-increasing source of problems. The IOMMU API has some fundamental
assumptions that iommu_probe_device() is called for every device added
to the system, in the order in which they are added. Calling it in a
random order or not at all dependent on driver binding leads to
malformed groups, a potential lack of isolation for devices with no
driver, and all manner of unexpected concurrency and race conditions.
We've attempted to mitigate the latter with point-fix bodges like
iommu_probe_device_lock, but it's a losing battle and the time has come
to bite the bullet and address the true source of the problem instead.
The crux of the matter is that the firmware parsing actually serves two
distinct purposes; one is identifying the IOMMU instance associated with
a device so we can check its availability, the second is actually
telling that instance about the relevant firmware-provided data for the
device. However the latter also depends on the former, and at the time
there was no good place to defer and retry that separately from the
availability check we also wanted for client driver probe.
Nowadays, though, we have a proper notion of multiple IOMMU instances in
the core API itself, and each one gets a chance to probe its own devices
upon registration, so we can finally make that work as intended for
DT/IORT/VIOT platforms too. All we need is for iommu_probe_device() to
be able to run the iommu_fwspec machinery currently buried deep in the
wrong end of {of,acpi}_dma_configure(). Luckily it turns out to be
surprisingly straightforward to bootstrap this transformation by pretty
much just calling the same path twice. At client driver probe time,
dev->driver is obviously set; conversely at device_add(), or a
subsequent bus_iommu_probe(), any device waiting for an IOMMU really
should *not* have a driver already, so we can use that as a condition to
disambiguate the two cases, and avoid recursing back into the IOMMU core
at the wrong times.
Obviously this isn't the nicest thing, but for now it gives us a
functional baseline to then unpick the layers in between without many
more awkward cross-subsystem patches. There are some minor side-effects
like dma_range_map potentially being created earlier, and some debug
prints being repeated, but these aren't significantly detrimental. Let's
make things work first, then deal with making them nice.
With the basic flow finally in the right order again, the next step is
probably turning the bus->dma_configure paths inside-out, since all we
really need from bus code is its notion of which device and input ID(s)
to parse the common firmware properties with...
Acked-by: Bjorn Helgaas <bhelgaas@google.com> # pci-driver.c
Acked-by: Rob Herring (Arm) <robh@kernel.org> # of/device.c
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/e3b191e6fd6ca9a1e84c5e5e40044faf97abb874.1740753261.git.robin.murphy@arm.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Juggling start, end, and size values for a range is somewhat redundant
and a little hard to follow. Consolidate down to just using inclusive
start and end, which saves us worrying about size overflows for full
64-bit ranges (note that passing a potentially-overflowed value through
to arch_setup_dma_ops() is benign for all current implementations, and
this is working towards removing that anyway).
Acked-by: Rob Herring <robh@kernel.org>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/3e0a72fe3d79eae660e4284bb32f2cb39868ccd7.1713523152.git.robin.murphy@arm.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
The fixup adding 1 to the dma-ranges size may have been for the benefit
of some early AMD Seattle DTs, or may have merely been a just-in-case,
but either way anyone who might have deserved to get the message has
hopefully seen the warning in the 9 years we've had it there. The modern
dma_range_map mechanism should happily handle odd-sized ranges with no
ill effect, so there's little need to care anyway now. Clean it up.
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/26620039901fdae52079ec1c8a4b2b324964a13e.1713523152.git.robin.murphy@arm.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Pull iommu updates from Joerg Roedel:
"Core changes:
- Fix race conditions in device probe path
- Retire IOMMU bus_ops
- Support for passing custom allocators to page table drivers
- Clean up Kconfig around IOMMU_SVA
- Support for sharing SVA domains with all devices bound to a mm
- Firmware data parsing cleanup
- Tracing improvements for iommu-dma code
- Some smaller fixes and cleanups
ARM-SMMU drivers:
- Device-tree binding updates:
- Add additional compatible strings for Qualcomm SoCs
- Document Adreno clocks for Qualcomm's SM8350 SoC
- SMMUv2:
- Implement support for the ->domain_alloc_paging() callback
- Ensure Secure context is restored following suspend of Qualcomm
SMMU implementation
- SMMUv3:
- Disable stalling mode for the "quiet" context descriptor
- Minor refactoring and driver cleanups
Intel VT-d driver:
- Cleanup and refactoring
AMD IOMMU driver:
- Improve IO TLB invalidation logic
- Small cleanups and improvements
Rockchip IOMMU driver:
- DT binding update to add Rockchip RK3588
Apple DART driver:
- Apple M1 USB4/Thunderbolt DART support
- Cleanups
Virtio IOMMU driver:
- Add support for iotlb_sync_map
- Enable deferred IO TLB flushes"
* tag 'iommu-updates-v6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (66 commits)
iommu: Don't reserve 0-length IOVA region
iommu/vt-d: Move inline helpers to header files
iommu/vt-d: Remove unused vcmd interfaces
iommu/vt-d: Remove unused parameter of intel_pasid_setup_pass_through()
iommu/vt-d: Refactor device_to_iommu() to retrieve iommu directly
iommu/sva: Fix memory leak in iommu_sva_bind_device()
dt-bindings: iommu: rockchip: Add Rockchip RK3588
iommu/dma: Trace bounce buffer usage when mapping buffers
iommu/arm-smmu: Convert to domain_alloc_paging()
iommu/arm-smmu: Pass arm_smmu_domain to internal functions
iommu/arm-smmu: Implement IOMMU_DOMAIN_BLOCKED
iommu/arm-smmu: Convert to a global static identity domain
iommu/arm-smmu: Reorganize arm_smmu_domain_add_master()
iommu/arm-smmu-v3: Remove ARM_SMMU_DOMAIN_NESTED
iommu/arm-smmu-v3: Master cannot be NULL in arm_smmu_write_strtab_ent()
iommu/arm-smmu-v3: Add a type for the STE
iommu/arm-smmu-v3: disable stall for quiet_cd
iommu/qcom: restore IOMMU state if needed
iommu/arm-smmu-qcom: Add QCM2290 MDSS compatible
iommu/arm-smmu-qcom: Add missing GMU entry to match table
...
Pull devicetree updates from Rob Herring:
"DT core:
- Add support for generating DT nodes for PCI devices. This is the
groundwork for applying overlays to PCI devices containing
non-discoverable downstream devices.
- DT unittest additions to check reverted changesets, to test for
refcount issues, and to test unresolved symbols. Also, various
clean-ups of the unittest along the way.
- Refactor node and property manipulation functions to better share
code with old API and changeset API
- Refactor changeset print functions to a common implementation
- Move some platform_device specific functions into of_platform.c
Bindings:
- Treewide fixing of typos
- Treewide clean-up of SPDX tags to use 'OR' consistently
- Last chunk of dropping unnecessary quotes. With that, the check for
unnecessary quotes is enabled in yamllint.
- Convert ftgmac100, zynqmp-genpd, pps-gpio, syna,rmi4, and qcom,ssbi
bindings to DT schema format
- Add Allwinner V3s xHCI USB, Saef SF-TC154B display, QCom SM8450
Inline Crypto Engine, QCom SM6115 UFS, QCom SDM670 PDC interrupt
controller, Arm 2022 Cortex cores, and QCom IPQ9574 Crypto bindings
- Fixes for Rockchip DWC PCI binding
- Ensure all properties are evaluated on USB connector schema
- Fix dt-check-compatible script to find of_device_id instances with
compiler annotations"
* tag 'devicetree-for-6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (64 commits)
dt-bindings: usb: Add V3s compatible string for OHCI
dt-bindings: usb: Add V3s compatible string for EHCI
dt-bindings: display: panel: mipi-dbi-spi: add Saef SF-TC154B
dt-bindings: vendor-prefixes: document Saef Technology
dt-bindings: thermal: lmh: update maintainer address
of: unittest: Fix of_unittest_pci_node() kconfig dependencies
dt-bindings: crypto: ice: Document sm8450 inline crypto engine
dt-bindings: ufs: qcom: Add ICE to sm8450 example
dt-bindings: ufs: qcom: Add sm6115 binding
dt-bindings: ufs: qcom: Add reg-names property for ICE
dt-bindings: yamllint: Enable quoted string check
dt-bindings: Drop remaining unneeded quotes
of: unittest-data: Fix whitespace - angular brackets
of: unittest-data: Fix whitespace - indentation
of: unittest-data: Fix whitespace - blank lines
of: unittest-data: Convert remaining overlay DTS files to sugar syntax
of: overlay: unittest: Add test for unresolved symbol
of: unittest: Add separators to of_unittest_overlay_high_level()
of: unittest: Cleanup partially-applied overlays
of: unittest: Merge of_unittest_apply{,_revert}_overlay_check()
...
The content of of_device_uevent() is currently hardcoded in a driver
that can be compiled as a module. Nothing prevents of_device_uevent() to
be exported to modules, most of the other helpers in of/device.c
actually are. The reason why this helper was not exported is because it
has been so far only useful in drivers/base, which is built-in anyway.
With the idea of getting rid of the hardcoded implementation of
of_device_uevent() in other places in the kernel, let's export it to GPL
modules (very much like its cousins in the same file).
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230622213214.3586530-2-miquel.raynal@bootlin.com
Create a specific .c file for OF related module handling.
Move of_modalias() inside as a first step.
The helper is exposed through of.h even though it is only used by core
files because the users from device.c will soon be split into an OF-only
helper in module.c as well as a device-oriented inline helper in
of_device.h. Putting this helper in of_private.h would require to
include of_private.h from of_device.h, which is not acceptable.
Suggested-by: Rob Herring <robh+dt@kernel.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20230404172148.82422-10-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This function only needs a "struct device_node" to work, but for
convenience the author (and only user) of this helper did use a "struct
device" and put it in device.c.
Let's convert this helper to take a "struct device node" instead. This
change asks for two additional changes: renaming it "of_modalias()"
to fit the current naming, and moving it outside of device.c which will
be done in a follow-up commit.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20230404172148.82422-8-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The helper generating an OF based modalias (of_device_get_modalias())
works fine, but due to the use of snprintf() internally it needs a
buffer one byte longer than what should be needed just for the entire
string (excluding the '\0'). Most users of this helper are sysfs hooks
providing the modalias string to users. They all provide a PAGE_SIZE
buffer which is way above the number of bytes required to fit the
modalias string and hence do not suffer from this issue.
There is another user though, of_device_request_module(), which is only
called by drivers/usb/common/ulpi.c. This request module function is
faulty, but maybe because in most cases there is an alternative, ULPI
driver users have not noticed it.
In this function, of_device_get_modalias() is called twice. The first
time without buffer just to get the number of bytes required by the
modalias string (excluding the null byte), and a second time, after
buffer allocation, to fill the buffer. The allocation asks for an
additional byte, in order to store the trailing '\0'. However, the
buffer *length* provided to of_device_get_modalias() excludes this extra
byte. The internal use of snprintf() with a length that is exactly the
number of bytes to be written has the effect of using the last available
byte to store a '\0', which then smashes the last character of the
modalias string.
Provide the actual size of the buffer to of_device_get_modalias() to fix
this issue.
Note: the "str[size - 1] = '\0';" line is not really needed as snprintf
will anyway end the string with a null byte, but there is a possibility
that this function might be called on a struct device_node without
compatible, in this case snprintf() would not be executed. So we keep it
just to avoid possible unbounded strings.
Cc: Stephen Boyd <sboyd@kernel.org>
Cc: Peter Chen <peter.chen@kernel.org>
Fixes: 9c829c097f ("of: device: Support loading a module with OF based modalias")
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20230404172148.82422-2-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull driver core updates from Greg KH:
"Here is the large set of driver core changes for 6.3-rc1.
There's a lot of changes this development cycle, most of the work
falls into two different categories:
- fw_devlink fixes and updates. This has gone through numerous review
cycles and lots of review and testing by lots of different devices.
Hopefully all should be good now, and Saravana will be keeping a
watch for any potential regression on odd embedded systems.
- driver core changes to work to make struct bus_type able to be
moved into read-only memory (i.e. const) The recent work with Rust
has pointed out a number of areas in the driver core where we are
passing around and working with structures that really do not have
to be dynamic at all, and they should be able to be read-only
making things safer overall. This is the contuation of that work
(started last release with kobject changes) in moving struct
bus_type to be constant. We didn't quite make it for this release,
but the remaining patches will be finished up for the release after
this one, but the groundwork has been laid for this effort.
Other than that we have in here:
- debugfs memory leak fixes in some subsystems
- error path cleanups and fixes for some never-able-to-be-hit
codepaths.
- cacheinfo rework and fixes
- Other tiny fixes, full details are in the shortlog
All of these have been in linux-next for a while with no reported
problems"
[ Geert Uytterhoeven points out that that last sentence isn't true, and
that there's a pending report that has a fix that is queued up - Linus ]
* tag 'driver-core-6.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (124 commits)
debugfs: drop inline constant formatting for ERR_PTR(-ERROR)
OPP: fix error checking in opp_migrate_dentry()
debugfs: update comment of debugfs_rename()
i3c: fix device.h kernel-doc warnings
dma-mapping: no need to pass a bus_type into get_arch_dma_ops()
driver core: class: move EXPORT_SYMBOL_GPL() lines to the correct place
Revert "driver core: add error handling for devtmpfs_create_node()"
Revert "devtmpfs: add debug info to handle()"
Revert "devtmpfs: remove return value of devtmpfs_delete_node()"
driver core: cpu: don't hand-override the uevent bus_type callback.
devtmpfs: remove return value of devtmpfs_delete_node()
devtmpfs: add debug info to handle()
driver core: add error handling for devtmpfs_create_node()
driver core: bus: update my copyright notice
driver core: bus: add bus_get_dev_root() function
driver core: bus: constify bus_unregister()
driver core: bus: constify some internal functions
driver core: bus: constify bus_get_kset()
driver core: bus: constify bus_register/unregister_notifier()
driver core: remove private pointer from struct bus_type
...
