When using GCC on x86-64 to compile an usdt prog with -O1 or higher
optimization, the compiler will generate SIB addressing mode for global
array, e.g. "1@-96(%rbp,%rax,8)".
In this patch:
- enrich subtest_basic_usdt test case to cover SIB addressing usdt argument spec
handling logic
Signed-off-by: Jiawei Zhao <phoenix500526@163.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20250827053128.1301287-3-phoenix500526@163.com
On x86-64, USDT arguments can be specified using Scale-Index-Base (SIB)
addressing, e.g. "1@-96(%rbp,%rax,8)". The current USDT implementation
in libbpf cannot parse this format, causing `bpf_program__attach_usdt()`
to fail with -ENOENT (unrecognized register).
This patch fixes this by implementing the necessary changes:
- add correct handling for SIB-addressed arguments in `bpf_usdt_arg`.
- add adaptive support to `__bpf_usdt_arg_type` and
`__bpf_usdt_arg_spec` to represent SIB addressing parameters.
Signed-off-by: Jiawei Zhao <phoenix500526@163.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20250827053128.1301287-2-phoenix500526@163.com
Introduce run.sh, a script to help with running VFIO selftests. The
script is intended to be used for both humans manually running VFIO
selftests, and to incorporate into test automation where VFIO selftests
may run alongside other tests. As such the script aims to be hermetic,
returning the system to the state it was before the test started.
The script takes as input the BDF of a device to use and a command to
run (typically the command would be a VFIO selftest). e.g.
$ ./run.sh -d 0000:6a:01.0 ./vfio_pci_device_test
or
$ ./run.sh -d 0000:6a:01.0 -- ./vfio_pci_device_test
The script then handles unbinding device 0000:6a:01.0 from its current
driver, binding it to vfio-pci, running the test, unbinding from
vfio-pci, and binding back to the original driver.
When run.sh runs the provided test, it does so by appending the BDF as
the last parameter. For example:
$ ./run.sh -d 0000:6a:01.0 -- echo hello
Results in the following being printed to stdout:
hello 0000:6a:01.0
The script also supports a mode where it can break out into a shell so
that multiple tests can be run manually.
$ ./run.sh -d 0000:6a:01.0 -s
$ echo $VFIO_SELFTESTS_BDF
$ ./vfio_pci_device_test
$ exit
Choosing which device to use is up to the user.
In the future this script should be extensible to tests that want to use
multiple devices. The script can support accepting -d BDF multiple times
and parse them into an array, setup all the devices, pass the list of
BDFs to the test, and then cleanup all the devices.
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: David Matlack <dmatlack@google.com>
Link: https://lore.kernel.org/r/20250822212518.4156428-31-dmatlack@google.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Add a driver to VFIO selftests for Intel DSA devices.
For now the driver only supports up to 32 batches and 1024 copies per
batch, which were the limits of the hardware this commit was tested
with. This is sufficient to generate 9+ minutes of DMA memcpys at a rate
of over 30 GB/s. This should be plenty to stress test VFIO and the IOMMU.
The driver does not yet support requesting interrupt handles, as this
commit was not tested against hardware that requires it.
Cc: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Acked-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: David Matlack <dmatlack@google.com>
Link: https://lore.kernel.org/r/20250822212518.4156428-23-dmatlack@google.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Add a driver for the Intel CBDMA device. This driver is based on and
named after the Linux driver for this device (drivers/dma/ioat/) and
also based on previous work from Peter Shier <pshier@google.com>.
The driver aims to be as simple as possible. It uses a single descriptor
to issue DMA operations, and only supports the copy operation. For "DMA
storms", the driver kicks off the maximum number of maximum-sized DMA
operations. On Skylake server parts, this was 2^16-1 copies of size 2M
and lasts about 15 seconds.
Create symlinks to drivers/dma/ioat/{hw.h,registers.h} to get access to
various macros (e.g. IOAT_CHANCMD_RESET) and struct ioat_dma_descriptor.
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Acked-by: Dave Jiang <dave.jiang@intel.com>
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: David Matlack <dmatlack@google.com>
Link: https://lore.kernel.org/r/20250822212518.4156428-20-dmatlack@google.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Import the asm-generic MMIO helper functions from the kernel headers
into tools/include/. The top-level include is <linux/io.h> which then
includes the arch-specific <asm/io.h>, which then includes
<asm-generic/io.h>. This layout is chosen to match the kernel header
layout and to appease checkpatch.pl (which warns against including
<asm/io.h> or <asm-generic/io.h> directly).
Changes made when importing:
- Add missing includes at the top.
- Stub out mmiowb_set_pending().
- Stub out _THIS_IP_.
- Stub out log_*_mmio() calls.
- Drop the CONFIG_64BIT checks, since tools/include/linux/types.h
always defines u64.
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: David Matlack <dmatlack@google.com>
Link: https://lore.kernel.org/r/20250822212518.4156428-16-dmatlack@google.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Add a driver framework to VFIO selftests, so that devices can generate
DMA and interrupts in a common way that can be then utilized by tests.
This will enable VFIO selftests to exercise real hardware DMA and
interrupt paths, without needing any device-specific code in the test
itself.
Subsequent commits will introduce drivers for specific devices.
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: David Matlack <dmatlack@google.com>
Link: https://lore.kernel.org/r/20250822212518.4156428-13-dmatlack@google.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Update vfio dma mapping test to verify that the IOMMU uses 2M and 1G
mappings when 2M and 1G HugeTLB pages are mapped into a device
respectively.
This validation is done by inspecting the contents of the I/O page
tables via /sys/kernel/debug/iommu/intel/. This validation is skipped if
that directory is not available (i.e. non-Intel IOMMUs).
Signed-off-by: Josh Hilke <jrhilke@google.com>
[reword commit message, refactor code]
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: David Matlack <dmatlack@google.com>
Link: https://lore.kernel.org/r/20250822212518.4156428-9-dmatlack@google.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Introduce a basic VFIO selftest called vfio_pci_device_test to
demonstrate the functionality of the VFIO selftest library and provide
some test coverage of basic VFIO operations, including:
- Mapping and unmapping DMA
- Mapping and unmapping BARs
- Enabling, triggering, and disabling MSI and MSI-x
- Reading and writing to PCI config space
This test should work with most PCI devices, as long as they are bound
to vfio-pci.
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: David Matlack <dmatlack@google.com>
Link: https://lore.kernel.org/r/20250822212518.4156428-4-dmatlack@google.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Add a basic helper library to be used by VFIO selftests.
The basic unit of the library is struct vfio_pci_device, which
represents a single PCI device that is bound to the vfio-pci driver. The
library currently only supports a single device per group and container,
and VFIO IOMMU types.
The code in this library was heavily based on prior work done by
Raghavendra Rao Ananta <rananta@google.com>, and the VFIO_ASSERT*()
macros were written by Vipin Sharma <vipinsh@google.com>.
Separate that Makefile rules for building the library into a separate
script so that the library can be built by and linked into KVM selftests
in a subsequent commit.
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: David Matlack <dmatlack@google.com>
Link: https://lore.kernel.org/r/20250822212518.4156428-3-dmatlack@google.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
The predicates in test expect event counting from 73e75e6fc3
("cgroup/pids: Separate semantics of pids.events related to pids.max")
and the test would fail on older kernels. We want to have one version of
tests for all, so detect the feature and skip the test on old kernels.
(The test could even switch to check v1 semantics based on the flag but
keep it simple for now.)
Fixes: 9f34c56602 ("selftests: cgroup: Add basic tests for pids controller")
Signed-off-by: Michal Koutný <mkoutny@suse.com>
Tested-by: Sebastian Chlad <sebastian.chlad@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Add a guest_memfd testcase to verify that a vCPU can fault-in guest_memfd
memory that supports mmap(), but that is not currently mapped into host
userspace and/or has a userspace address (in the memslot) that points at
something other than the target guest_memfd range. Mapping guest_memfd
memory into the guest is supposed to operate completely independently from
any userspace mappings.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-ID: <20250729225455.670324-25-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Expand the guest_memfd selftests to comprehensively test host userspace
mmap functionality for guest_memfd-backed memory when supported by the
VM type.
Introduce new test cases to verify the following:
* Successful mmap operations: Ensure that MAP_SHARED mappings succeed
when guest_memfd mmap is enabled.
* Data integrity: Validate that data written to the mmap'd region is
correctly persistent and readable.
* fallocate interaction: Test that fallocate(FALLOC_FL_PUNCH_HOLE)
correctly zeros out mapped pages.
* Out-of-bounds access: Verify that accessing memory beyond the
guest_memfd's size correctly triggers a SIGBUS signal.
* Unsupported mmap: Confirm that mmap attempts fail as expected when
guest_memfd mmap support is not enabled for the specific guest_memfd
instance or VM type.
* Flag validity: Introduce test_vm_type_gmem_flag_validity() to
systematically test that only allowed guest_memfd creation flags are
accepted for different VM types (e.g., GUEST_MEMFD_FLAG_MMAP for
default VMs, no flags for CoCo VMs).
The existing tests for guest_memfd creation (multiple instances, invalid
sizes), file read/write, file size, and invalid punch hole operations
are integrated into the new test_with_type() framework to allow testing
across different VM types.
Cc: James Houghton <jthoughton@google.com>
Cc: Gavin Shan <gshan@redhat.com>
Cc: Shivank Garg <shivankg@amd.com>
Co-developed-by: Ackerley Tng <ackerleytng@google.com>
Signed-off-by: Ackerley Tng <ackerleytng@google.com>
Signed-off-by: Fuad Tabba <tabba@google.com>
Co-developed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-ID: <20250729225455.670324-24-seanjc@google.com>
[Fix default vm_types to use BIT() - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Update the guest_memfd_test selftest to use getpagesize() instead of
hardcoded 4KB page size values.
Using hardcoded page sizes can cause test failures on architectures or
systems configured with larger page sizes, such as arm64 with 64KB
pages. By dynamically querying the system's page size, the test becomes
more portable and robust across different environments.
Additionally, build the guest_memfd_test selftest for arm64.
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Shivank Garg <shivankg@amd.com>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Suggested-by: Gavin Shan <gshan@redhat.com>
Signed-off-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-ID: <20250729225455.670324-23-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* Use array_index_nospec() to sanitize the target vCPU ID when handling PV
IPIs and yields as the ID is guest-controlled.
* Drop a superfluous cpumask_empty() check when reclaiming SEV memory, as
the common case, by far, is that at least one CPU will have entered the
VM, and wbnoinvd_on_cpus_mask() will naturally handle the rare case where
the set of have_run_cpus is empty.
* Rename the is_signed_type() macro in kselftest_harness.h to is_signed_var()
to fix a collision with linux/overflow.h. The collision generates compiler
warnings due to the two macros having different implementations.
KVM x86 fixes and a selftest fix for 6.17-rcN
- Use array_index_nospec() to sanitize the target vCPU ID when handling PV
IPIs and yields as the ID is guest-controlled.
- Drop a superfluous cpumask_empty() check when reclaiming SEV memory, as
the common case, by far, is that at least one CPU will have entered the
VM, and wbnoinvd_on_cpus_mask() will naturally handle the rare case where
the set of have_run_cpus is empty.
- Rename the is_signed_type() macro in kselftest_harness.h to is_signed_var()
to fix a collision with linux/overflow.h. The collision generates compiler
warnings due to the two macros having different implementations.
