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 v3:
- Make pylint happy (Simon)
- Remove the unnecessary patch in bpftrace to raise an exception when it
fails. (Jakub)
- Improved the bpftrace code (Willem)
- Stop sending messages if bpftrace is not alive anymore.
- Link to v2: https://lore.kernel.org/r/20250625-netpoll_test-v2-0-47d27775222c@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 (2):
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 +
.../selftests/drivers/net/lib/py/__init__.py | 3 +-
.../testing/selftests/drivers/net/netpoll_basic.py | 345 +++++++++++++++++++++
tools/testing/selftests/net/lib/py/utils.py | 35 +++
4 files changed, 383 insertions(+), 1 deletion(-)
---
base-commit: 8efa26fcbf8a7f783fd1ce7dd2a409e9b7758df0
change-id: 20250612-netpoll_test-a1324d2057c8
Best regards,
--
Breno Leitao <leitao(a)debian.org>
Fix a typo:
instaces -> instances
The typo has been identified using codespell, and the tool does not
report any additional issues in the selftests considered.
Signed-off-by: Andrea Mayer <andrea.mayer(a)uniroma2.it>
---
tools/testing/selftests/net/srv6_end_next_csid_l3vpn_test.sh | 2 +-
tools/testing/selftests/net/srv6_end_x_next_csid_l3vpn_test.sh | 2 +-
tools/testing/selftests/net/srv6_hencap_red_l3vpn_test.sh | 2 +-
tools/testing/selftests/net/srv6_hl2encap_red_l2vpn_test.sh | 2 +-
4 files changed, 4 insertions(+), 4 deletions(-)
diff --git a/tools/testing/selftests/net/srv6_end_next_csid_l3vpn_test.sh b/tools/testing/selftests/net/srv6_end_next_csid_l3vpn_test.sh
index ba730655a7bf..4bc135e5c22c 100755
--- a/tools/testing/selftests/net/srv6_end_next_csid_l3vpn_test.sh
+++ b/tools/testing/selftests/net/srv6_end_next_csid_l3vpn_test.sh
@@ -594,7 +594,7 @@ setup_rt_local_sids()
dev "${DUMMY_DEVNAME}"
# all SIDs for VPNs start with a common locator. Routes and SRv6
- # Endpoint behavior instaces are grouped together in the 'localsid'
+ # Endpoint behavior instances are grouped together in the 'localsid'
# table.
ip -netns "${nsname}" -6 rule \
add to "${VPN_LOCATOR_SERVICE}::/16" \
diff --git a/tools/testing/selftests/net/srv6_end_x_next_csid_l3vpn_test.sh b/tools/testing/selftests/net/srv6_end_x_next_csid_l3vpn_test.sh
index bedf0ce885c2..34b781a2ae74 100755
--- a/tools/testing/selftests/net/srv6_end_x_next_csid_l3vpn_test.sh
+++ b/tools/testing/selftests/net/srv6_end_x_next_csid_l3vpn_test.sh
@@ -681,7 +681,7 @@ setup_rt_local_sids()
set_underlay_sids_reachability "${rt}" "${rt_neighs}"
# all SIDs for VPNs start with a common locator. Routes and SRv6
- # Endpoint behavior instaces are grouped together in the 'localsid'
+ # Endpoint behavior instances are grouped together in the 'localsid'
# table.
ip -netns "${nsname}" -6 rule \
add to "${VPN_LOCATOR_SERVICE}::/16" \
diff --git a/tools/testing/selftests/net/srv6_hencap_red_l3vpn_test.sh b/tools/testing/selftests/net/srv6_hencap_red_l3vpn_test.sh
index 3efce1718c5f..6a68c7eff1dc 100755
--- a/tools/testing/selftests/net/srv6_hencap_red_l3vpn_test.sh
+++ b/tools/testing/selftests/net/srv6_hencap_red_l3vpn_test.sh
@@ -395,7 +395,7 @@ setup_rt_local_sids()
dev "${VRF_DEVNAME}"
# all SIDs for VPNs start with a common locator. Routes and SRv6
- # Endpoint behavior instaces are grouped together in the 'localsid'
+ # Endpoint behavior instances are grouped together in the 'localsid'
# table.
ip -netns "${nsname}" -6 rule \
add to "${VPN_LOCATOR_SERVICE}::/16" \
diff --git a/tools/testing/selftests/net/srv6_hl2encap_red_l2vpn_test.sh b/tools/testing/selftests/net/srv6_hl2encap_red_l2vpn_test.sh
index cabc70538ffe..0979b5316fdf 100755
--- a/tools/testing/selftests/net/srv6_hl2encap_red_l2vpn_test.sh
+++ b/tools/testing/selftests/net/srv6_hl2encap_red_l2vpn_test.sh
@@ -343,7 +343,7 @@ setup_rt_local_sids()
encap seg6local action End dev "${DUMMY_DEVNAME}"
# all SIDs for VPNs start with a common locator. Routes and SRv6
- # Endpoint behaviors instaces are grouped together in the 'localsid'
+ # Endpoint behaviors instances are grouped together in the 'localsid'
# table.
ip -netns "${nsname}" -6 rule add \
to "${VPN_LOCATOR_SERVICE}::/16" \
--
2.20.1
FEAT_LSFE is optional from v9.5, it adds new instructions for atomic
memory operations with floating point values. We have no immediate use
for it in kernel, provide a hwcap so userspace can discover it and allow
the ID register field to be exposed to KVM guests.
Signed-off-by: Mark Brown <broonie(a)kernel.org>
---
Mark Brown (3):
arm64/hwcap: Add hwcap for FEAT_LSFE
KVM: arm64: Expose FEAT_LSFE to guests
kselftest/arm64: Add lsfe to the hwcaps test
Documentation/arch/arm64/elf_hwcaps.rst | 4 ++++
arch/arm64/include/asm/hwcap.h | 1 +
arch/arm64/include/uapi/asm/hwcap.h | 1 +
arch/arm64/kernel/cpufeature.c | 2 ++
arch/arm64/kernel/cpuinfo.c | 1 +
arch/arm64/kvm/sys_regs.c | 4 +++-
tools/testing/selftests/arm64/abi/hwcap.c | 21 +++++++++++++++++++++
7 files changed, 33 insertions(+), 1 deletion(-)
---
base-commit: 86731a2a651e58953fc949573895f2fa6d456841
change-id: 20250625-arm64-lsfe-0810cf98adc2
Best regards,
--
Mark Brown <broonie(a)kernel.org>
This series introduces NUMA-aware memory placement support for KVM guests
with guest_memfd memory backends. It builds upon Fuad Tabba's work that
enabled host-mapping for guest_memfd memory [1] and can be applied directly
on KVM tree (branch:queue, base commit:7915077245) [2].
== Background ==
KVM's guest-memfd memory backend currently lacks support for NUMA policy
enforcement, causing guest memory allocations to be distributed across host
nodes according to kernel's default behavior, irrespective of any policy
specified by the VMM. This limitation arises because conventional userspace
NUMA control mechanisms like mbind(2) don't work since the memory isn't
directly mapped to userspace when allocations occur.
Fuad's work [1] provides the necessary mmap capability, and this series
leverages it to enable mbind(2).
== Implementation ==
This series implements proper NUMA policy support for guest-memfd by:
1. Adding mempolicy-aware allocation APIs to the filemap layer.
2. Introducing custom inodes (via a dedicated slab-allocated inode cache,
kvm_gmem_inode_info) to store NUMA policy and metadata for guest memory.
3. Implementing get/set_policy vm_ops in guest_memfd to support NUMA
policy.
With these changes, VMMs can now control guest memory placement by mapping
guest_memfd file descriptor and using mbind(2) to specify:
- Policy modes: default, bind, interleave, or preferred
- Host NUMA nodes: List of target nodes for memory allocation
These Policies affect only future allocations and do not migrate existing
memory. This matches mbind(2)'s default behavior which affects only new
allocations unless overridden with MPOL_MF_MOVE/MPOL_MF_MOVE_ALL flags (Not
supported for guest_memfd as it is unmovable by design).
== Upstream Plan ==
Phased approach as per David's guest_memfd extension overview [3] and
community calls [4]:
Phase 1 (this series):
1. Focuses on shared guest_memfd support (non-CoCo VMs).
2. Builds on Fuad's host-mapping work.
Phase2 (future work):
1. NUMA support for private guest_memfd (CoCo VMs).
2. Depends on SNP in-place conversion support [5].
This series provides a clean integration path for NUMA-aware memory
management for guest_memfd and lays the groundwork for future confidential
computing NUMA capabilities.
Please review and provide feedback!
Thanks,
Shivank
== Changelog ==
- v1,v2: Extended the KVM_CREATE_GUEST_MEMFD IOCTL to pass mempolicy.
- v3: Introduced fbind() syscall for VMM memory-placement configuration.
- v4-v6: Current approach using shared_policy support and vm_ops (based on
suggestions from David [6] and guest_memfd bi-weekly upstream
call discussion [7]).
- v7: Use inodes to store NUMA policy instead of file [8].
- v8: Rebase on top of Fuad's V12: Host mmaping for guest_memfd memory.
[1] https://lore.kernel.org/all/20250611133330.1514028-1-tabba@google.com
[2] https://git.kernel.org/pub/scm/virt/kvm/kvm.git/log/?h=queue
[3] https://lore.kernel.org/all/c1c9591d-218a-495c-957b-ba356c8f8e09@redhat.com
[4] https://docs.google.com/document/d/1M6766BzdY1Lhk7LiR5IqVR8B8mG3cr-cxTxOrAo…
[5] https://lore.kernel.org/all/20250613005400.3694904-1-michael.roth@amd.com
[6] https://lore.kernel.org/all/6fbef654-36e2-4be5-906e-2a648a845278@redhat.com
[7] https://lore.kernel.org/all/2b77e055-98ac-43a1-a7ad-9f9065d7f38f@amd.com
[8] https://lore.kernel.org/all/diqzbjumm167.fsf@ackerleytng-ctop.c.googlers.com
Ackerley Tng (1):
KVM: guest_memfd: Use guest mem inodes instead of anonymous inodes
Shivank Garg (5):
security: Export anon_inode_make_secure_inode for KVM guest_memfd
mm/mempolicy: Export memory policy symbols
KVM: guest_memfd: Add slab-allocated inode cache
KVM: guest_memfd: Enforce NUMA mempolicy using shared policy
KVM: guest_memfd: selftests: Add tests for mmap and NUMA policy
support
Shivansh Dhiman (1):
mm/filemap: Add mempolicy support to the filemap layer
fs/anon_inodes.c | 20 +-
include/linux/fs.h | 2 +
include/linux/pagemap.h | 41 +++
include/uapi/linux/magic.h | 1 +
mm/filemap.c | 27 +-
mm/mempolicy.c | 6 +
tools/testing/selftests/kvm/Makefile.kvm | 1 +
.../testing/selftests/kvm/guest_memfd_test.c | 123 ++++++++-
virt/kvm/guest_memfd.c | 254 ++++++++++++++++--
virt/kvm/kvm_main.c | 7 +-
virt/kvm/kvm_mm.h | 10 +-
11 files changed, 456 insertions(+), 36 deletions(-)
--
2.43.0
---
== Earlier Postings ==
v7: https://lore.kernel.org/all/20250408112402.181574-1-shivankg@amd.com
v6: https://lore.kernel.org/all/20250226082549.6034-1-shivankg@amd.com
v5: https://lore.kernel.org/all/20250219101559.414878-1-shivankg@amd.com
v4: https://lore.kernel.org/all/20250210063227.41125-1-shivankg@amd.com
v3: https://lore.kernel.org/all/20241105164549.154700-1-shivankg@amd.com
v2: https://lore.kernel.org/all/20240919094438.10987-1-shivankg@amd.com
v1: https://lore.kernel.org/all/20240916165743.201087-1-shivankg@amd.com
DAMON sysfs interface is the bridge between the user space and the
kernel space for DAMON parameters. There is no good and simple test to
see if the parameters are set as expected. Existing DAMON selftests
therefore test end-to-end features. For example, damos_quota_goal.py
runs a DAMOS scheme with quota goal set against a test program running
an artificial access pattern, and see if the result is as expected.
Such tests cover only a few part of DAMON. Adding more tests is also
complicated. Finally, the reliability of the test itself on different
systems is bad.
'drgn' is a tool that can extract kernel internal data structures like
DAMON parameters. Add a test that passes specific DAMON parameters via
DAMON sysfs reusing _damon_sysfs.py, extract resulting DAMON parameters
via 'drgn', and compare those. Note that this test is not adding
exhaustive tests of all DAMON parameters and input combinations but very
basic things. Advancing the test infrastructure and adding more tests
are future works.
Changes from RFC
(https://lore.kernel.org/20250622210330.40490-1-sj@kernel.org)
- Rebase on latest mm-new
SeongJae Park (6):
selftests/damon: add drgn script for extracting damon status
selftests/damon/_damon_sysfs: set Kdamond.pid in start()
selftests/damon: add python and drgn-based DAMON sysfs test
selftests/damon/sysfs.py: test monitoring attribute parameters
selftests/damon/sysfs.py: test adaptive targets parameter
selftests/damon/sysfs.py: test DAMOS schemes parameters setup
tools/testing/selftests/damon/Makefile | 1 +
tools/testing/selftests/damon/_damon_sysfs.py | 3 +
.../selftests/damon/drgn_dump_damon_status.py | 161 ++++++++++++++++++
tools/testing/selftests/damon/sysfs.py | 115 +++++++++++++
4 files changed, 280 insertions(+)
create mode 100755 tools/testing/selftests/damon/drgn_dump_damon_status.py
create mode 100755 tools/testing/selftests/damon/sysfs.py
base-commit: 5ab6feac2d83ebbf0d0d2eedf0505878ba677dcb
--
2.39.5
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