Fix cur_aux()->nospec_result test after do_check_insn() referring to the
to-be-analyzed (potentially unsafe) instruction, not the
already-analyzed (safe) instruction. This might allow a unsafe insn to
slip through on a speculative path. Create some tests from the
reproducer [1].
Commit d6f1c85f2253 ("bpf: Fall back to nospec for Spectre v1") should
not be in any stable kernel yet, therefore bpf-next should suffice.
[1] https://lore.kernel.org/bpf/685b3c1b.050a0220.2303ee.0010.GAE@google.com/
Changes since RFC:
- Introduce prev_aux() as suggested by Alexei. For this, we must move
the env->prev_insn_idx assignment to happen directly after
do_check_insn(), for which I have created a separate commit. This
patch could be simplified by using a local prev_aux variable as
sugested by Eduard, but I figured one might find the new
assignment-strategy easier to understand (before, prev_insn_idx and
env->prev_insn_idx were out-of-sync for the latter part of the loop).
Also, like this we do not have an additional prev_* variable that must
be kept in-sync and the local variable's usage (old prev_insn_idx, new
tmp) is much more local. If you think it would be better to not take
the risk and keep the fix simple by just introducing the prev_aux
variable, let me know.
- Change WARN_ON_ONCE() to verifier_bug_if() as suggested by Alexei
- Change assertion to check instruction is BPF_JMP[32] as suggested by
Eduard
- RFC: https://lore.kernel.org/bpf/8734bmoemx.fsf@fau.de/
Luis Gerhorst (3):
bpf: Update env->prev_insn_idx after do_check_insn()
bpf: Fix aux usage after do_check_insn()
selftests/bpf: Add Spectre v4 tests
kernel/bpf/verifier.c | 30 ++--
tools/testing/selftests/bpf/progs/bpf_misc.h | 4 +
.../selftests/bpf/progs/verifier_unpriv.c | 149 ++++++++++++++++++
3 files changed, 174 insertions(+), 9 deletions(-)
base-commit: d69bafe6ee2b5eff6099fa26626ecc2963f0f363
--
2.49.0
glibc does not define SYS_futex for 32-bit architectures using 64-bit
time_t e.g. riscv32, therefore this test fails to compile since it does not
find SYS_futex in C library headers. Define SYS_futex as SYS_futex_time64
in this situation to ensure successful compilation and compatibility.
Signed-off-by: Cynthia Huang <cynthia(a)andestech.com>
Signed-off-by: Ben Zong-You Xie <ben717(a)andestech.com>
---
Changes since v1:
- Fix the SOB chain
v1 : https://lore.kernel.org/all/20250527093536.3646143-1-ben717@andestech.com/
---
tools/testing/selftests/futex/include/futextest.h | 11 +++++++++++
1 file changed, 11 insertions(+)
diff --git a/tools/testing/selftests/futex/include/futextest.h b/tools/testing/selftests/futex/include/futextest.h
index ddbcfc9b7bac..7a5fd1d5355e 100644
--- a/tools/testing/selftests/futex/include/futextest.h
+++ b/tools/testing/selftests/futex/include/futextest.h
@@ -47,6 +47,17 @@ typedef volatile u_int32_t futex_t;
FUTEX_PRIVATE_FLAG)
#endif
+/*
+ * SYS_futex is expected from system C library, in glibc some 32-bit
+ * architectures (e.g. RV32) are using 64-bit time_t, therefore it doesn't have
+ * SYS_futex defined but just SYS_futex_time64. Define SYS_futex as
+ * SYS_futex_time64 in this situation to ensure the compilation and the
+ * compatibility.
+ */
+#if !defined(SYS_futex) && defined(SYS_futex_time64)
+#define SYS_futex SYS_futex_time64
+#endif
+
/**
* futex() - SYS_futex syscall wrapper
* @uaddr: address of first futex
--
2.34.1
Changes in v2:
- Removed lints are not replaced with `expect` in the first diff.
- Removals are done in separate diffs for each.
The `#[allow(clippy::non_send_fields_in_send_ty)]` removal was tested
on 1.81 and clippy was still happy with it. I couldn't test it on 1.78
because when I go below 1.81 `menuconfig` no longer shows the Rust option.
And any manual changes I make to `.config` are immediately reverted on
`make` invocations.
Onur Özkan (3):
replace `#[allow(...)]` with `#[expect(...)]`
rust: remove `#[allow(clippy::unnecessary_cast)]`
rust: remove `#[allow(clippy::non_send_fields_in_send_ty)]`
drivers/gpu/nova-core/regs.rs | 2 +-
rust/compiler_builtins.rs | 2 +-
rust/kernel/alloc/allocator_test.rs | 2 +-
rust/kernel/cpufreq.rs | 1 -
rust/kernel/devres.rs | 2 +-
rust/kernel/driver.rs | 2 +-
rust/kernel/drm/ioctl.rs | 8 ++++----
rust/kernel/error.rs | 3 +--
rust/kernel/init.rs | 6 +++---
rust/kernel/kunit.rs | 2 +-
rust/kernel/opp.rs | 4 ++--
rust/kernel/types.rs | 2 +-
rust/macros/helpers.rs | 2 +-
13 files changed, 18 insertions(+), 20 deletions(-)
--
2.50.0
This patch series was initially sent to security(a)k.o; resending it in
public. I might follow-up with a tests series which addresses similar
issues with TIOCLINUX.
===============
The TIOCSTI ioctl uses capable(CAP_SYS_ADMIN) for access control, which
checks the current process's credentials. However, it doesn't validate
against the file opener's credentials stored in file->f_cred.
This creates a potential security issue where an unprivileged process
can open a TTY fd and pass it to a privileged process via SCM_RIGHTS.
The privileged process may then inadvertently grant access based on its
elevated privileges rather than the original opener's credentials.
Background
==========
As noted in previous discussion, while CONFIG_LEGACY_TIOCSTI can restrict
TIOCSTI usage, it is enabled by default in most distributions. Even when
CONFIG_LEGACY_TIOCSTI=n, processes with CAP_SYS_ADMIN can still use TIOCSTI
according to the Kconfig documentation.
Additionally, CONFIG_LEGACY_TIOCSTI controls the default value for the
dev.tty.legacy_tiocsti sysctl, which remains runtime-configurable. This
means the described attack vector could work on systems even with
CONFIG_LEGACY_TIOCSTI=n, particularly on Ubuntu 24.04 where it's "restricted"
but still functional.
Solution Approach
=================
This series addresses the issue through SELinux LSM integration rather
than modifying core TTY credential checking to avoid potential compatibility
issues with existing userspace.
The enhancement adds proper current task and file credential capability
validation in SELinux's selinux_file_ioctl() hook specifically for
TIOCSTI operations.
Testing
=======
All patches have been validated using:
- scripts/checkpatch.pl --strict (0 errors, 0 warnings)
- Functional testing on kernel v6.16-rc2
- File descriptor passing security test scenarios
- SELinux policy enforcement testing
The fd_passing_security test demonstrates the security concern.
To verify, disable legacy TIOCSTI and run the test:
$ echo "0" | sudo tee /proc/sys/dev/tty/legacy_tiocsti
$ sudo ./tools/testing/selftests/tty/tty_tiocsti_test -t fd_passing_security
Patch Overview
==============
PATCH 1/2: selftests/tty: add TIOCSTI test suite
Comprehensive test suite demonstrating the issue and fix validation
PATCH 2/2: selinux: add capability checks for TIOCSTI ioctl
Core security enhancement via SELinux LSM hook
References
==========
- tty_ioctl(4) - documents TIOCSTI ioctl and capability requirements
- commit 83efeeeb3d04 ("tty: Allow TIOCSTI to be disabled")
- Documentation/security/credentials.rst
- https://github.com/KSPP/linux/issues/156
- https://lore.kernel.org/linux-hardening/Y0m9l52AKmw6Yxi1@hostpad/
- drivers/tty/Kconfig
Configuration References:
[1] - https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/dri…
[2] - https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/dri…
[3] - https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/dri…
To: Shuah Khan <shuah(a)kernel.org>
To: Nathan Chancellor <nathan(a)kernel.org>
To: Nick Desaulniers <nick.desaulniers+lkml(a)gmail.com>
To: Bill Wendling <morbo(a)google.com>
To: Justin Stitt <justinstitt(a)google.com>
To: Paul Moore <paul(a)paul-moore.com>
To: Stephen Smalley <stephen.smalley.work(a)gmail.com>
To: Ondrej Mosnacek <omosnace(a)redhat.com>
Cc: linux-kernel(a)vger.kernel.org
Cc: linux-kselftest(a)vger.kernel.org
Cc: llvm(a)lists.linux.dev
Cc: selinux(a)vger.kernel.org
Signed-off-by: Abhinav Saxena <xandfury(a)gmail.com>
---
Abhinav Saxena (2):
selftests/tty: add TIOCSTI test suite
selinux: add capability checks for TIOCSTI ioctl
security/selinux/hooks.c | 6 +
tools/testing/selftests/tty/Makefile | 6 +-
tools/testing/selftests/tty/config | 1 +
tools/testing/selftests/tty/tty_tiocsti_test.c | 421 +++++++++++++++++++++++++
4 files changed, 433 insertions(+), 1 deletion(-)
---
base-commit: 5adb635077d1b4bd65b183022775a59a378a9c00
change-id: 20250618-toicsti-bug-7822b8e94a32
Best regards,
--
Abhinav Saxena <xandfury(a)gmail.com>
The kernel has recently added support for shadow stacks, currently
x86 only using their CET feature but both arm64 and RISC-V have
equivalent features (GCS and Zicfiss respectively), I am actively
working on GCS[1]. With shadow stacks the hardware maintains an
additional stack containing only the return addresses for branch
instructions which is not generally writeable by userspace and ensures
that any returns are to the recorded addresses. This provides some
protection against ROP attacks and making it easier to collect call
stacks. These shadow stacks are allocated in the address space of the
userspace process.
Our API for shadow stacks does not currently offer userspace any
flexiblity for managing the allocation of shadow stacks for newly
created threads, instead the kernel allocates a new shadow stack with
the same size as the normal stack whenever a thread is created with the
feature enabled. The stacks allocated in this way are freed by the
kernel when the thread exits or shadow stacks are disabled for the
thread. This lack of flexibility and control isn't ideal, in the vast
majority of cases the shadow stack will be over allocated and the
implicit allocation and deallocation is not consistent with other
interfaces. As far as I can tell the interface is done in this manner
mainly because the shadow stack patches were in development since before
clone3() was implemented.
Since clone3() is readily extensible let's add support for specifying a
shadow stack when creating a new thread or process, keeping the current
implicit allocation behaviour if one is not specified either with
clone3() or through the use of clone(). The user must provide a shadow
stack pointer, this must point to memory mapped for use as a shadow
stackby map_shadow_stack() with an architecture specified shadow stack
token at the top of the stack.
Yuri Khrustalev has raised questions from the libc side regarding
discoverability of extended clone3() structure sizes[2], this seems like
a general issue with clone3(). There was a suggestion to add a hwcap on
arm64 which isn't ideal but is doable there, though architecture
specific mechanisms would also be needed for x86 (and RISC-V if it's
support gets merged before this does).
Please note that the x86 portions of this code are build tested only, I
don't appear to have a system that can run CET available to me.
[1] https://lore.kernel.org/linux-arm-kernel/20241001-arm64-gcs-v13-0-222b78d87…
[2] https://lore.kernel.org/r/aCs65ccRQtJBnZ_5@arm.com
Signed-off-by: Mark Brown <broonie(a)kernel.org>
---
Changes in v17:
- Rebase onto v6.16-rc1.
- Link to v16: https://lore.kernel.org/r/20250416-clone3-shadow-stack-v16-0-2ffc9ca3917b@k…
Changes in v16:
- Rebase onto v6.15-rc2.
- Roll in fixes from x86 testing from Rick Edgecombe.
- Rework so that the argument is shadow_stack_token.
- Link to v15: https://lore.kernel.org/r/20250408-clone3-shadow-stack-v15-0-3fa245c6e3be@k…
Changes in v15:
- Rebase onto v6.15-rc1.
- Link to v14: https://lore.kernel.org/r/20250206-clone3-shadow-stack-v14-0-805b53af73b9@k…
Changes in v14:
- Rebase onto v6.14-rc1.
- Link to v13: https://lore.kernel.org/r/20241203-clone3-shadow-stack-v13-0-93b89a81a5ed@k…
Changes in v13:
- Rebase onto v6.13-rc1.
- Link to v12: https://lore.kernel.org/r/20241031-clone3-shadow-stack-v12-0-7183eb8bee17@k…
Changes in v12:
- Add the regular prctl() to the userspace API document since arm64
support is queued in -next.
- Link to v11: https://lore.kernel.org/r/20241005-clone3-shadow-stack-v11-0-2a6a2bd6d651@k…
Changes in v11:
- Rebase onto arm64 for-next/gcs, which is based on v6.12-rc1, and
integrate arm64 support.
- Rework the interface to specify a shadow stack pointer rather than a
base and size like we do for the regular stack.
- Link to v10: https://lore.kernel.org/r/20240821-clone3-shadow-stack-v10-0-06e8797b9445@k…
Changes in v10:
- Integrate fixes & improvements for the x86 implementation from Rick
Edgecombe.
- Require that the shadow stack be VM_WRITE.
- Require that the shadow stack base and size be sizeof(void *) aligned.
- Clean up trailing newline.
- Link to v9: https://lore.kernel.org/r/20240819-clone3-shadow-stack-v9-0-962d74f99464@ke…
Changes in v9:
- Pull token validation earlier and report problems with an error return
to parent rather than signal delivery to the child.
- Verify that the top of the supplied shadow stack is VM_SHADOW_STACK.
- Rework token validation to only do the page mapping once.
- Drop no longer needed support for testing for signals in selftest.
- Fix typo in comments.
- Link to v8: https://lore.kernel.org/r/20240808-clone3-shadow-stack-v8-0-0acf37caf14c@ke…
Changes in v8:
- Fix token verification with user specified shadow stack.
- Don't track user managed shadow stacks for child processes.
- Link to v7: https://lore.kernel.org/r/20240731-clone3-shadow-stack-v7-0-a9532eebfb1d@ke…
Changes in v7:
- Rebase onto v6.11-rc1.
- Typo fixes.
- Link to v6: https://lore.kernel.org/r/20240623-clone3-shadow-stack-v6-0-9ee7783b1fb9@ke…
Changes in v6:
- Rebase onto v6.10-rc3.
- Ensure we don't try to free the parent shadow stack in error paths of
x86 arch code.
- Spelling fixes in userspace API document.
- Additional cleanups and improvements to the clone3() tests to support
the shadow stack tests.
- Link to v5: https://lore.kernel.org/r/20240203-clone3-shadow-stack-v5-0-322c69598e4b@ke…
Changes in v5:
- Rebase onto v6.8-rc2.
- Rework ABI to have the user allocate the shadow stack memory with
map_shadow_stack() and a token.
- Force inlining of the x86 shadow stack enablement.
- Move shadow stack enablement out into a shared header for reuse by
other tests.
- Link to v4: https://lore.kernel.org/r/20231128-clone3-shadow-stack-v4-0-8b28ffe4f676@ke…
Changes in v4:
- Formatting changes.
- Use a define for minimum shadow stack size and move some basic
validation to fork.c.
- Link to v3: https://lore.kernel.org/r/20231120-clone3-shadow-stack-v3-0-a7b8ed3e2acc@ke…
Changes in v3:
- Rebase onto v6.7-rc2.
- Remove stale shadow_stack in internal kargs.
- If a shadow stack is specified unconditionally use it regardless of
CLONE_ parameters.
- Force enable shadow stacks in the selftest.
- Update changelogs for RISC-V feature rename.
- Link to v2: https://lore.kernel.org/r/20231114-clone3-shadow-stack-v2-0-b613f8681155@ke…
Changes in v2:
- Rebase onto v6.7-rc1.
- Remove ability to provide preallocated shadow stack, just specify the
desired size.
- Link to v1: https://lore.kernel.org/r/20231023-clone3-shadow-stack-v1-0-d867d0b5d4d0@ke…
---
Mark Brown (8):
arm64/gcs: Return a success value from gcs_alloc_thread_stack()
Documentation: userspace-api: Add shadow stack API documentation
selftests: Provide helper header for shadow stack testing
fork: Add shadow stack support to clone3()
selftests/clone3: Remove redundant flushes of output streams
selftests/clone3: Factor more of main loop into test_clone3()
selftests/clone3: Allow tests to flag if -E2BIG is a valid error code
selftests/clone3: Test shadow stack support
Documentation/userspace-api/index.rst | 1 +
Documentation/userspace-api/shadow_stack.rst | 44 +++++
arch/arm64/include/asm/gcs.h | 8 +-
arch/arm64/kernel/process.c | 8 +-
arch/arm64/mm/gcs.c | 61 +++++-
arch/x86/include/asm/shstk.h | 11 +-
arch/x86/kernel/process.c | 2 +-
arch/x86/kernel/shstk.c | 57 +++++-
include/asm-generic/cacheflush.h | 11 ++
include/linux/sched/task.h | 17 ++
include/uapi/linux/sched.h | 9 +-
kernel/fork.c | 96 +++++++--
tools/testing/selftests/clone3/clone3.c | 226 ++++++++++++++++++----
tools/testing/selftests/clone3/clone3_selftests.h | 65 ++++++-
tools/testing/selftests/ksft_shstk.h | 98 ++++++++++
15 files changed, 633 insertions(+), 81 deletions(-)
---
base-commit: 19272b37aa4f83ca52bdf9c16d5d81bdd1354494
change-id: 20231019-clone3-shadow-stack-15d40d2bf536
Best regards,
--
Mark Brown <broonie(a)kernel.org>
Rename is_signed_type() to is_signed_var() to avoid colliding with a macro
of the same name defined by linux/overflow.h. Note, overflow.h's version
takes a type as the input, whereas the harness's version takes a variable!
This fixes warnings (and presumably potential test failures) in tests
that utilize the selftests harness and happen to (indirectly) include
overflow.h.
In file included from tools/include/linux/bits.h:34,
from tools/include/linux/bitops.h:14,
from tools/include/linux/hashtable.h:13,
from include/kvm_util.h:11,
from x86/userspace_msr_exit_test.c:11:
tools/include/linux/overflow.h:31:9: error: "is_signed_type" redefined [-Werror]
31 | #define is_signed_type(type) (((type)(-1)) < (type)1)
| ^~~~~~~~~~~~~~
In file included from include/kvm_test_harness.h:11,
from x86/userspace_msr_exit_test.c:9:
../kselftest_harness.h:754:9: note: this is the location of the previous definition
754 | #define is_signed_type(var) (!!(((__typeof__(var))(-1)) < (__typeof__(var))1))
| ^~~~~~~~~~~~~~
Opportunistically use is_signed_type() to implement is_signed_var() so
that the relationship and differences are obvious.
Fixes: fc92099902fb ("tools headers: Synchronize linux/bits.h with the kernel sources")
Cc: Vincent Mailhol <mailhol.vincent(a)wanadoo.fr>
Cc: Arnaldo Carvalho de Melo <acme(a)redhat.com>
Signed-off-by: Sean Christopherson <seanjc(a)google.com>
---
This is probably compile-tested only, I don't think any of the KVM selftests
utilize the harness's EXPECT macros.
tools/testing/selftests/kselftest_harness.h | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/tools/testing/selftests/kselftest_harness.h b/tools/testing/selftests/kselftest_harness.h
index 2925e47db995..f3e7a46345db 100644
--- a/tools/testing/selftests/kselftest_harness.h
+++ b/tools/testing/selftests/kselftest_harness.h
@@ -56,6 +56,7 @@
#include <asm/types.h>
#include <ctype.h>
#include <errno.h>
+#include <linux/overflow.h>
#include <linux/unistd.h>
#include <poll.h>
#include <stdbool.h>
@@ -751,7 +752,7 @@
for (; _metadata->trigger; _metadata->trigger = \
__bail(_assert, _metadata))
-#define is_signed_type(var) (!!(((__typeof__(var))(-1)) < (__typeof__(var))1))
+#define is_signed_var(var) is_signed_type(__typeof__(var))
#define __EXPECT(_expected, _expected_str, _seen, _seen_str, _t, _assert) do { \
/* Avoid multiple evaluation of the cases */ \
@@ -759,7 +760,7 @@
__typeof__(_seen) __seen = (_seen); \
if (!(__exp _t __seen)) { \
/* Report with actual signedness to avoid weird output. */ \
- switch (is_signed_type(__exp) * 2 + is_signed_type(__seen)) { \
+ switch (is_signed_var(__exp) * 2 + is_signed_var(__seen)) { \
case 0: { \
uintmax_t __exp_print = (uintmax_t)__exp; \
uintmax_t __seen_print = (uintmax_t)__seen; \
base-commit: 78f4e737a53e1163ded2687a922fce138aee73f5
--
2.50.0.714.g196bf9f422-goog
Various KUnit tests require PCI infrastructure to work.
All normal platforms enable PCI by default, but UML does not.
Enabling PCI from .kunitconfig files is problematic as it would not be
portable. So in commit 6fc3a8636a7b ("kunit: tool: Enable virtio/PCI by default on UML")
PCI was enabled by way of CONFIG_UML_PCI_OVER_VIRTIO=y.
However CONFIG_UML_PCI_OVER_VIRTIO requires additional configuration of
CONFIG_UML_PCI_OVER_VIRTIO_DEVICE_ID or will otherwise trigger a WARN() in
virtio_pcidev_init(). However there is no one correct value for
UML_PCI_OVER_VIRTIO_DEVICE_ID which could be used by default.
This warning is confusing when debugging test failures.
On the other hand, the functionality of CONFIG_UML_PCI_OVER_VIRTIO is not
used at all, given that it is completely non-functional as indicated by
the WARN() in question. Instead it is only used as a way to enable
CONFIG_UML_PCI which itself is not directly configurable.
Instead of going through CONFIG_UML_PCI_OVER_VIRTIO, introduce a custom
configuration option which enables CONFIG_UML_PCI without triggering
warnings or building dead code.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh(a)linutronix.de>
---
lib/kunit/Kconfig | 7 +++++++
tools/testing/kunit/configs/arch_uml.config | 5 ++---
2 files changed, 9 insertions(+), 3 deletions(-)
diff --git a/lib/kunit/Kconfig b/lib/kunit/Kconfig
index a97897edd9642f3e5df7fdd9dee26ee5cf00d6a4..c8ca155521b2455a221ddbec3f6fc55662c83475 100644
--- a/lib/kunit/Kconfig
+++ b/lib/kunit/Kconfig
@@ -93,4 +93,11 @@ config KUNIT_AUTORUN_ENABLED
In most cases this should be left as Y. Only if additional opt-in
behavior is needed should this be set to N.
+config KUNIT_UML_PCI
+ bool "KUnit UML PCI Support"
+ depends on UML
+ select UML_PCI
+ help
+ Enables the PCI subsystem on UML for use by KUnit tests.
+
endif # KUNIT
diff --git a/tools/testing/kunit/configs/arch_uml.config b/tools/testing/kunit/configs/arch_uml.config
index 54ad8972681a2cc724e6122b19407188910b9025..28edf816aa70e6f408d9486efff8898df79ee090 100644
--- a/tools/testing/kunit/configs/arch_uml.config
+++ b/tools/testing/kunit/configs/arch_uml.config
@@ -1,8 +1,7 @@
# Config options which are added to UML builds by default
-# Enable virtio/pci, as a lot of tests require it.
-CONFIG_VIRTIO_UML=y
-CONFIG_UML_PCI_OVER_VIRTIO=y
+# Enable pci, as a lot of tests require it.
+CONFIG_KUNIT_UML_PCI=y
# Enable FORTIFY_SOURCE for wider checking.
CONFIG_FORTIFY_SOURCE=y
---
base-commit: 19272b37aa4f83ca52bdf9c16d5d81bdd1354494
change-id: 20250626-kunit-uml-pci-a2b687553746
Best regards,
--
Thomas Weißschuh <thomas.weissschuh(a)linutronix.de>
I am submitting a new selftest for the netpoll subsystem specifically
targeting the case where the RX is polling in the TX path, which is
a case that we don't have any test in the tree today. This is done when
netpoll_poll_dev() called, and this test creates a scenario when that is
probably.
The test does the following:
1) Configuring a single RX/TX queue to increase contention on the
interface.
2) Generating background traffic to saturate the network, mimicking
real-world congestion.
3) Sending netconsole messages to trigger netpoll polling and monitor
its behavior.
4) Using dynamic netconsole targets via configfs, with the ability to
delete and recreate targets during the test.
5) Running bpftrace in parallel to verify that netpoll_poll_dev() is
called when expected. If it is called, then the test passes,
otherwise the test is marked as skipped.
In order to achieve it, I stole Jakub's bpftrace helper from [1], and
did some small changes that I found useful to use the helper.
So, this patchset basically contains:
1) The code stolen from Jakub
2) Improvements on bpftrace() helper
3) The selftest itself
Link: https://lore.kernel.org/all/20250421222827.283737-22-kuba@kernel.org/ [1]
---
Changes in v1 (from RFC):
- Toggle the netconsole interfaces up and down after 5 iterations.
- Moved the traffic check under DEBUG (Willem de Bruijn).
- Bumped the iterations to 20 given it runs faster now.
- Link to the RFC: https://lore.kernel.org/r/20250612-netpoll_test-v1-1-4774fd95933f@debian.org
---
Changes in v2:
- Stole Jakub's helper to run bpftrace
- Removed the DEBUG option and moved logs to logging
- Change the code to have a higher chance of calling netpoll_poll_dev().
In my current configuration, it is hitting multiple times during the
test.
- Save and restore TX/RX queue size (Jakub)
- Link to v1: https://lore.kernel.org/r/20250620-netpoll_test-v1-1-5068832f72fc@debian.org
---
Breno Leitao (3):
selftests: drv-net: Improve bpftrace utility error handling
selftests: drv-net: Strip '@' prefix from bpftrace map keys
selftests: net: add netpoll basic functionality test
Jakub Kicinski (1):
selftests: drv-net: add helper/wrapper for bpftrace
tools/testing/selftests/drivers/net/Makefile | 1 +
.../testing/selftests/drivers/net/netpoll_basic.py | 344 +++++++++++++++++++++
tools/testing/selftests/net/lib/py/utils.py | 38 +++
3 files changed, 383 insertions(+)
---
base-commit: eb4c27edb4d8dbfbdcc7bc03e0394a0fab8af7d5
change-id: 20250612-netpoll_test-a1324d2057c8
Best regards,
--
Breno Leitao <leitao(a)debian.org>