Recently, I noticed a selftest failure in my local environment. The
test_parse_test_list_file writes some data to
/tmp/bpf_arg_parsing_test.XXXXXX and parse_test_list_file() will read
the data back. However, after writing data to that file, we forget to
call fsync() and it's causing testing failure in my laptop. This patch
helps fix it by adding the missing fsync() call.
Signed-off-by: Xing Guo <higuoxing(a)gmail.com>
---
tools/testing/selftests/bpf/prog_tests/arg_parsing.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/tools/testing/selftests/bpf/prog_tests/arg_parsing.c b/tools/testing/selftests/bpf/prog_tests/arg_parsing.c
index bb143de68875..4f071943ffb0 100644
--- a/tools/testing/selftests/bpf/prog_tests/arg_parsing.c
+++ b/tools/testing/selftests/bpf/prog_tests/arg_parsing.c
@@ -140,6 +140,7 @@ static void test_parse_test_list_file(void)
fprintf(fp, "testA/subtest2\n");
fprintf(fp, "testC_no_eof_newline");
fflush(fp);
+ fsync(fd);
if (!ASSERT_OK(ferror(fp), "prepare tmp"))
goto out_fclose;
--
2.51.0
This patch series suggests fixes for several corner cases in the RISC-V
vector ptrace implementation:
- follow gdbserver expectations and return ENODATA instead of EINVAL if vector
extension is supported but not yet activated for a traced process
- force vector context save on the next context switch after ptrace call that
modified vector CSRs, to avoid reading stale values by the next ptrace calls
- force vector context save on the first context switch after vector context
initialization, to avoid reading zero vlenb by an early attached debugger
For detailed description see the appropriate commit messages. A new test is
added into the tools/testing/selftests/riscv/vector to verify the fixes.
Each fix is accompanied by its own test case.
Initial version [1] of this series included only the last fix for zero vlenb.
[1] https://lore.kernel.org/linux-riscv/20250821173957.563472-1-geomatsi@gmail.…
Ilya Mamay (1):
riscv: ptrace: return ENODATA for inactive vector extension
Sergey Matyukevich (5):
selftests: riscv: test ptrace vector interface
selftests: riscv: set invalid vtype using ptrace
riscv: vector: allow to force vector context save
selftests: riscv: verify initial vector state with ptrace
riscv: vector: initialize vlenb on the first context switch
arch/riscv/include/asm/thread_info.h | 2 +
arch/riscv/include/asm/vector.h | 3 +
arch/riscv/kernel/process.c | 2 +
arch/riscv/kernel/ptrace.c | 15 +-
arch/riscv/kernel/vector.c | 4 +
.../testing/selftests/riscv/vector/.gitignore | 1 +
tools/testing/selftests/riscv/vector/Makefile | 5 +-
.../testing/selftests/riscv/vector/v_ptrace.c | 302 ++++++++++++++++++
8 files changed, 331 insertions(+), 3 deletions(-)
create mode 100644 tools/testing/selftests/riscv/vector/v_ptrace.c
base-commit: c746c3b5169831d7fb032a1051d8b45592ae8d78
--
2.51.0
Introduce SW acceleration for IPIP tunnels in the netfilter flowtable
infrastructure.
---
Changes in v6:
- Rebase on top of nf-next main branch
- Link to v5: https://lore.kernel.org/r/20250721-nf-flowtable-ipip-v5-0-0865af9e58c6@kern…
Changes in v5:
- Rely on __ipv4_addr_hash() to compute the hash used as encap ID
- Remove unnecessary pskb_may_pull() in nf_flow_tuple_encap()
- Add nf_flow_ip4_ecanp_pop utility routine
- Link to v4: https://lore.kernel.org/r/20250718-nf-flowtable-ipip-v4-0-f8bb1c18b986@kern…
Changes in v4:
- Use the hash value of the saddr, daddr and protocol of outer IP header as
encapsulation id.
- Link to v3: https://lore.kernel.org/r/20250703-nf-flowtable-ipip-v3-0-880afd319b9f@kern…
Changes in v3:
- Add outer IP header sanity checks
- target nf-next tree instead of net-next
- Link to v2: https://lore.kernel.org/r/20250627-nf-flowtable-ipip-v2-0-c713003ce75b@kern…
Changes in v2:
- Introduce IPIP flowtable selftest
- Link to v1: https://lore.kernel.org/r/20250623-nf-flowtable-ipip-v1-1-2853596e3941@kern…
---
Lorenzo Bianconi (2):
net: netfilter: Add IPIP flowtable SW acceleration
selftests: netfilter: nft_flowtable.sh: Add IPIP flowtable selftest
include/linux/netdevice.h | 1 +
net/ipv4/ipip.c | 28 +++++++++++
net/netfilter/nf_flow_table_ip.c | 56 +++++++++++++++++++++-
net/netfilter/nft_flow_offload.c | 1 +
.../selftests/net/netfilter/nft_flowtable.sh | 40 ++++++++++++++++
5 files changed, 124 insertions(+), 2 deletions(-)
---
base-commit: bab3ce404553de56242d7b09ad7ea5b70441ea41
change-id: 20250623-nf-flowtable-ipip-1b3d7b08d067
Best regards,
--
Lorenzo Bianconi <lorenzo(a)kernel.org>
[All the precursor patches are merged now and AMD/RISCV/VTD conversions
are written]
Currently each of the iommu page table formats duplicates all of the logic
to maintain the page table and perform map/unmap/etc operations. There are
several different versions of the algorithms between all the different
formats. The io-pgtable system provides an interface to help isolate the
page table code from the iommu driver, but doesn't provide tools to
implement the common algorithms.
This makes it very hard to improve the state of the pagetable code under
the iommu domains as any proposed improvement needs to alter a large
number of different driver code paths. Combined with a lack of software
based testing this makes improvement in this area very hard.
iommufd wants several new page table operations:
- More efficient map/unmap operations, using iommufd's batching logic
- unmap that returns the physical addresses into a batch as it progresses
- cut that allows splitting areas so large pages can have holes
poked in them dynamically (ie guestmemfd hitless shared/private
transitions)
- More agressive freeing of table memory to avoid waste
- Fragmenting large pages so that dirty tracking can be more granular
- Reassembling large pages so that VMs can run at full IO performance
in migration/dirty tracking error flows
- KHO integration for kernel live upgrade
Together these are algorithmically complex enough to be a very significant
task to go and implement in all the page table formats we support. Just
the "server" focused drivers use almost all the formats (ARMv8 S1&S2 / x86
PAE / AMDv1 / VT-D SS / RISCV)
Instead of doing the duplicated work, this series takes the first step to
consolidate the algorithms into one places. In spirit it is similar to the
work Christoph did a few years back to pull the redundant get_user_pages()
implementations out of the arch code into core MM. This unlocked a great
deal of improvement in that space in the following years. I would like to
see the same benefit in iommu as well.
My first RFC showed a bigger picture with all most all formats and more
algorithms. This series reorganizes that to be narrowly focused on just
enough to convert the AMD driver to use the new mechanism.
kunit tests are provided that allow good testing of the algorithms and all
formats on x86, nothing is arch specific.
AMD is one of the simpler options as the HW is quite uniform with few
different options/bugs while still requiring the complicated contiguous
pages support. The HW also has a very simple range based invalidation
approach that is easy to implement.
The AMD v1 and AMD v2 page table formats are implemented bit for bit
identical to the current code, tested using a compare kunit test that
checks against the io-pgtable version (on github, see below).
Updating the AMD driver to replace the io-pgtable layer with the new stuff
is fairly straightforward now. The layering is fixed up in the new version
so that all the invalidation goes through function pointers.
Several small fixing patches have come out of this as I've been fixing the
problems that the test suite uncovers in the current code, and
implementing the fixed version in iommupt.
On performance, there is a quite wide variety of implementation designs
across all the drivers. Looking at some key performance across
the main formats:
iommu_map():
pgsz ,avg new,old ns, min new,old ns , min % (+ve is better)
2^12, 53,66 , 51,63 , 19.19 (AMDV1)
256*2^12, 386,1909 , 367,1795 , 79.79
256*2^21, 362,1633 , 355,1556 , 77.77
2^12, 56,62 , 52,59 , 11.11 (AMDv2)
256*2^12, 405,1355 , 357,1292 , 72.72
256*2^21, 393,1160 , 358,1114 , 67.67
2^12, 55,65 , 53,62 , 14.14 (VTD second stage)
256*2^12, 391,518 , 332,512 , 35.35
256*2^21, 383,635 , 336,624 , 46.46
2^12, 57,65 , 55,63 , 12.12 (ARM 64 bit)
256*2^12, 380,389 , 361,369 , 2.02
256*2^21, 358,419 , 345,400 , 13.13
iommu_unmap():
pgsz ,avg new,old ns, min new,old ns , min % (+ve is better)
2^12, 69,88 , 65,85 , 23.23 (AMDv1)
256*2^12, 353,6498 , 331,6029 , 94.94
256*2^21, 373,6014 , 360,5706 , 93.93
2^12, 71,72 , 66,69 , 4.04 (AMDv2)
256*2^12, 228,891 , 206,871 , 76.76
256*2^21, 254,721 , 245,711 , 65.65
2^12, 69,87 , 65,82 , 20.20 (VTD second stage)
256*2^12, 210,321 , 200,315 , 36.36
256*2^21, 255,349 , 238,342 , 30.30
2^12, 72,77 , 68,74 , 8.08 (ARM 64 bit)
256*2^12, 521,357 , 447,346 , -29.29
256*2^21, 489,358 , 433,345 , -25.25
* Above numbers include additional patches to remove the iommu_pgsize()
overheads. gcc 13.3.0, i7-12700
This version provides fairly consistent performance across formats. ARM
unmap performance is quite different because this version supports
contiguous pages and uses a very different algorithm for unmapping. Though
why it is so worse compared to AMDv1 I haven't figured out yet.
The per-format commits include a more detailed chart.
There is a second branch:
https://github.com/jgunthorpe/linux/commits/iommu_pt_all
Containing supporting work and future steps:
- ARM short descriptor (32 bit), ARM long descriptor (64 bit) formats
- RISCV format and RISCV conversion
https://github.com/jgunthorpe/linux/commits/iommu_pt_riscv
- Support for a DMA incoherent HW page table walker
- VT-D second stage format and VT-D conversion
https://github.com/jgunthorpe/linux/commits/iommu_pt_vtd
- DART v1 & v2 format
- Draft of a iommufd 'cut' operation to break down huge pages
- A compare test that checks the iommupt formats against the iopgtable
interface, including updating AMD to have a working iopgtable and patches
to make VT-D have an iopgtable for testing.
- A performance test to micro-benchmark map and unmap against iogptable
My strategy is to go one by one for the drivers:
- AMD driver conversion
- RISCV page table and driver
- Intel VT-D driver and VTDSS page table
- Flushing improvements for RISCV
- ARM SMMUv3
And concurrently work on the algorithm side:
- debugfs content dump, like VT-D has
- Cut support
- Increase/Decrease page size support
- map/unmap batching
- KHO
As we make more algorithm improvements the value to convert the drivers
increases.
This is on github: https://github.com/jgunthorpe/linux/commits/iommu_pt
v6:
- Improve comments and documentation
- Rename pt_entry_oa_full -> pt_entry_oa_exact
pt_has_system_page -> pt_has_system_page_size
pt_max_output_address_lg2 -> pt_max_oa_lg2
log2_f*() -> vaf* / oaf* / f*_t
pt_item_fully_covered -> pt_entry_fully_covered
- Fix missed constant propogation causing division
- Consolidate debugging checks to pt_check_install_leaf_args()
- Change collect->ignore_mapped to check_mapped
- Shuffle some hunks around to more appropriate patches
- Two new mini kunit tests
v5: https://patch.msgid.link/r/0-v5-116c4948af3d+68091-iommu_pt_jgg@nvidia.com
- Text grammar updates and kdoc fixes
v4: https://patch.msgid.link/r/0-v4-0d6a6726a372+18959-iommu_pt_jgg@nvidia.com
- Rebase on v6.16-rc3
- Integrate the HATS/HATDis changes
- Remove 'default n' from kconfig
- Remove unused 'PT_FIXED_TOP_LEVEL'
- Improve comments and documentation
- Fix some compile warnings from kbuild robots
v3: https://patch.msgid.link/r/0-v3-a93aab628dbc+521-iommu_pt_jgg@nvidia.com
- Rebase on v6.16-rc2
- s/PT_ENTRY_WORD_SIZE/PT_ITEM_WORD_SIZE/s to follow the language better
- Comment and documentation updates
- Add PT_TOP_PHYS_MASK to help manage alignment restrictions on the top
pointer
- Add missed force_aperture = true
- Make pt_iommu_deinit() take care of the not-yet-inited error case
internally as AMD/RISCV/VTD all shared this logic
- Change gather_range() into gather_range_pages() so it also deals with
the page list. This makes the following cache flushing series simpler
- Fix missed update of unmap->unmapped in some error cases
- Change clear_contig() to order the gather more logically
- Remove goto from the error handling in __map_range_leaf()
- s/log2_/oalog2_/ in places where the argument is an oaddr_t
- Pass the pts to pt_table_install64/32()
- Do not use SIGN_EXTEND for the AMDv2 page table because of Vasant's
information on how PASID 0 works.
v2: https://patch.msgid.link/r/0-v2-5c26bde5c22d+58b-iommu_pt_jgg@nvidia.com
- AMD driver only, many code changes
RFC: https://lore.kernel.org/all/0-v1-01fa10580981+1d-iommu_pt_jgg@nvidia.com/
Cc: Michael Roth <michael.roth(a)amd.com>
Cc: Alexey Kardashevskiy <aik(a)amd.com>
Cc: Pasha Tatashin <pasha.tatashin(a)soleen.com>
Cc: James Gowans <jgowans(a)amazon.com>
Signed-off-by: Jason Gunthorpe <jgg(a)nvidia.com>
Alejandro Jimenez (1):
iommu/amd: Use the generic iommu page table
Jason Gunthorpe (14):
genpt: Generic Page Table base API
genpt: Add Documentation/ files
iommupt: Add the basic structure of the iommu implementation
iommupt: Add the AMD IOMMU v1 page table format
iommupt: Add iova_to_phys op
iommupt: Add unmap_pages op
iommupt: Add map_pages op
iommupt: Add read_and_clear_dirty op
iommupt: Add a kunit test for Generic Page Table
iommupt: Add a mock pagetable format for iommufd selftest to use
iommufd: Change the selftest to use iommupt instead of xarray
iommupt: Add the x86 64 bit page table format
iommu/amd: Remove AMD io_pgtable support
iommupt: Add a kunit test for the IOMMU implementation
.clang-format | 1 +
Documentation/driver-api/generic_pt.rst | 142 ++
Documentation/driver-api/index.rst | 1 +
drivers/iommu/Kconfig | 2 +
drivers/iommu/Makefile | 1 +
drivers/iommu/amd/Kconfig | 5 +-
drivers/iommu/amd/Makefile | 2 +-
drivers/iommu/amd/amd_iommu.h | 1 -
drivers/iommu/amd/amd_iommu_types.h | 110 +-
drivers/iommu/amd/io_pgtable.c | 577 --------
drivers/iommu/amd/io_pgtable_v2.c | 370 ------
drivers/iommu/amd/iommu.c | 538 ++++----
drivers/iommu/generic_pt/.kunitconfig | 13 +
drivers/iommu/generic_pt/Kconfig | 67 +
drivers/iommu/generic_pt/fmt/Makefile | 26 +
drivers/iommu/generic_pt/fmt/amdv1.h | 408 ++++++
drivers/iommu/generic_pt/fmt/defs_amdv1.h | 21 +
drivers/iommu/generic_pt/fmt/defs_x86_64.h | 21 +
drivers/iommu/generic_pt/fmt/iommu_amdv1.c | 15 +
drivers/iommu/generic_pt/fmt/iommu_mock.c | 10 +
drivers/iommu/generic_pt/fmt/iommu_template.h | 48 +
drivers/iommu/generic_pt/fmt/iommu_x86_64.c | 11 +
drivers/iommu/generic_pt/fmt/x86_64.h | 251 ++++
drivers/iommu/generic_pt/iommu_pt.h | 1157 +++++++++++++++++
drivers/iommu/generic_pt/kunit_generic_pt.h | 713 ++++++++++
drivers/iommu/generic_pt/kunit_iommu.h | 182 +++
drivers/iommu/generic_pt/kunit_iommu_pt.h | 486 +++++++
drivers/iommu/generic_pt/pt_common.h | 358 +++++
drivers/iommu/generic_pt/pt_defs.h | 329 +++++
drivers/iommu/generic_pt/pt_fmt_defaults.h | 233 ++++
drivers/iommu/generic_pt/pt_iter.h | 636 +++++++++
drivers/iommu/generic_pt/pt_log2.h | 122 ++
drivers/iommu/io-pgtable.c | 4 -
drivers/iommu/iommufd/Kconfig | 1 +
drivers/iommu/iommufd/iommufd_test.h | 11 +-
drivers/iommu/iommufd/selftest.c | 438 +++----
include/linux/generic_pt/common.h | 167 +++
include/linux/generic_pt/iommu.h | 270 ++++
include/linux/io-pgtable.h | 2 -
tools/testing/selftests/iommu/iommufd.c | 60 +-
tools/testing/selftests/iommu/iommufd_utils.h | 12 +
41 files changed, 6212 insertions(+), 1610 deletions(-)
create mode 100644 Documentation/driver-api/generic_pt.rst
delete mode 100644 drivers/iommu/amd/io_pgtable.c
delete mode 100644 drivers/iommu/amd/io_pgtable_v2.c
create mode 100644 drivers/iommu/generic_pt/.kunitconfig
create mode 100644 drivers/iommu/generic_pt/Kconfig
create mode 100644 drivers/iommu/generic_pt/fmt/Makefile
create mode 100644 drivers/iommu/generic_pt/fmt/amdv1.h
create mode 100644 drivers/iommu/generic_pt/fmt/defs_amdv1.h
create mode 100644 drivers/iommu/generic_pt/fmt/defs_x86_64.h
create mode 100644 drivers/iommu/generic_pt/fmt/iommu_amdv1.c
create mode 100644 drivers/iommu/generic_pt/fmt/iommu_mock.c
create mode 100644 drivers/iommu/generic_pt/fmt/iommu_template.h
create mode 100644 drivers/iommu/generic_pt/fmt/iommu_x86_64.c
create mode 100644 drivers/iommu/generic_pt/fmt/x86_64.h
create mode 100644 drivers/iommu/generic_pt/iommu_pt.h
create mode 100644 drivers/iommu/generic_pt/kunit_generic_pt.h
create mode 100644 drivers/iommu/generic_pt/kunit_iommu.h
create mode 100644 drivers/iommu/generic_pt/kunit_iommu_pt.h
create mode 100644 drivers/iommu/generic_pt/pt_common.h
create mode 100644 drivers/iommu/generic_pt/pt_defs.h
create mode 100644 drivers/iommu/generic_pt/pt_fmt_defaults.h
create mode 100644 drivers/iommu/generic_pt/pt_iter.h
create mode 100644 drivers/iommu/generic_pt/pt_log2.h
create mode 100644 include/linux/generic_pt/common.h
create mode 100644 include/linux/generic_pt/iommu.h
base-commit: cc1d7df505790fe734117b41455f1fe82ebf5ae5
--
2.43.0
Problem
=======
When host APEI is unable to claim a synchronous external abort (SEA)
during guest abort, today KVM directly injects an asynchronous SError
into the VCPU then resumes it. The injected SError usually results in
unpleasant guest kernel panic.
One of the major situation of guest SEA is when VCPU consumes recoverable
uncorrected memory error (UER), which is not uncommon at all in modern
datacenter servers with large amounts of physical memory. Although SError
and guest panic is sufficient to stop the propagation of corrupted memory,
there is room to recover from an UER in a more graceful manner.
Proposed Solution
=================
The idea is, we can replay the SEA to the faulting VCPU. If the memory
error consumption or the fault that cause SEA is not from guest kernel,
the blast radius can be limited to the poison-consuming guest process,
while the VM can keep running.
In addition, instead of doing under the hood without involving userspace,
there are benefits to redirect the SEA to VMM:
- VM customers care about the disruptions caused by memory errors, and
VMM usually has the responsibility to start the process of notifying
the customers of memory error events in their VMs. For example some
cloud provider emits a critical log in their observability UI [1], and
provides a playbook for customers on how to mitigate disruptions to
their workloads.
- VMM can protect future memory error consumption by unmapping the poisoned
pages from stage-2 page table with KVM userfault [2], or by splitting the
memslot that contains the poisoned pages.
- VMM can keep track of SEA events in the VM. When VMM thinks the status
on the host or the VM is bad enough, e.g. number of distinct SEAs
exceeds a threshold, it can restart the VM on another healthy host.
- Behavior parity with x86 architecture. When machine check exception
(MCE) is caused by VCPU, kernel or KVM signals userspace SIGBUS to
let VMM either recover from the MCE, or terminate itself with VM.
The prior RFC proposes to implement SIGBUS on arm64 as well, but
Marc preferred KVM exit over signal [3]. However, implementation
aside, returning SEA to VMM is on par with returning MCE to VMM.
Once SEA is redirected to VMM, among other actions, VMM is encouraged
to inject external aborts into the faulting VCPU.
New UAPIs
=========
This patchset introduces following userspace-visible changes to empower
VMM to control what happens for SEA on guest memory:
- KVM_CAP_ARM_SEA_TO_USER. While taking SEA, if userspace has enabled
this new capability at VM creation, and the SEA is not owned by kernel
allocated memory, instead of injecting SError, return KVM_EXIT_ARM_SEA
to userspace.
- KVM_EXIT_ARM_SEA. This is the VM exit reason VMM gets. The details
about the SEA is provided in arm_sea as much as possible, including
sanitized ESR value at EL2, faulting guest virtual and physical
addresses if available.
* From v3 [4]
- Rebased on commit 3a8660878839 ("Linux 6.18-rc1").
- In selftest, print a message if GVA or GPA expects to be valid.
* From v2 [5]:
- Rebased on "[PATCH] KVM: arm64: nv: Handle SEAs due to VNCR redirection" [6]
and kvmarm/next commit 7b8346bd9fce6 ("KVM: arm64: Don't attempt vLPI
mappings when vPE allocation is disabled")
- Took the host_owns_sea implementation from Oliver [7, 8].
- Excluded the guest SEA injection patches.
- Updated selftest.
* From v1 [9]:
- Rebased on commit 4d62121ce9b5 ("KVM: arm64: vgic-debug: Avoid
dereferencing NULL ITE pointer").
- Sanitize ESR_EL2 before reporting it to userspace.
- Do not do KVM_EXIT_ARM_SEA when SEA is caused by memory allocated to
stage-2 translation table.
[1] https://cloud.google.com/solutions/sap/docs/manage-host-errors
[2] https://lore.kernel.org/kvm/20250109204929.1106563-1-jthoughton@google.com
[3] https://lore.kernel.org/kvm/86pljbqqh0.wl-maz@kernel.org
[4] https://lore.kernel.org/kvmarm/20250731205844.1346839-1-jiaqiyan@google.com
[5] https://lore.kernel.org/kvm/20250604050902.3944054-1-jiaqiyan@google.com
[6] https://lore.kernel.org/kvmarm/20250729182342.3281742-1-oliver.upton@linux.…
[7] https://lore.kernel.org/kvm/aHFohmTb9qR_JG1E@linux.dev
[8] https://lore.kernel.org/kvm/aHK-DPufhLy5Dtuk@linux.dev
[9] https://lore.kernel.org/kvm/20250505161412.1926643-1-jiaqiyan@google.com
Jiaqi Yan (3):
KVM: arm64: VM exit to userspace to handle SEA
KVM: selftests: Test for KVM_EXIT_ARM_SEA
Documentation: kvm: new UAPI for handling SEA
Documentation/virt/kvm/api.rst | 61 ++++
arch/arm64/include/asm/kvm_host.h | 2 +
arch/arm64/kvm/arm.c | 5 +
arch/arm64/kvm/mmu.c | 68 +++-
include/uapi/linux/kvm.h | 10 +
tools/arch/arm64/include/asm/esr.h | 2 +
tools/testing/selftests/kvm/Makefile.kvm | 1 +
.../testing/selftests/kvm/arm64/sea_to_user.c | 331 ++++++++++++++++++
tools/testing/selftests/kvm/lib/kvm_util.c | 1 +
9 files changed, 480 insertions(+), 1 deletion(-)
create mode 100644 tools/testing/selftests/kvm/arm64/sea_to_user.c
--
2.51.0.760.g7b8bcc2412-goog
This series addresses comments and combines into one the two
series [1] and [2], and adds review-bys.
This series refactors the KHO framework to better support in-kernel
users like the upcoming LUO. The current design, which relies on a
notifier chain and debugfs for control, is too restrictive for direct
programmatic use.
The core of this rework is the removal of the notifier chain in favor of
a direct registration API. This decouples clients from the shutdown-time
finalization sequence, allowing them to manage their preserved state
more flexibly and at any time.
Also, this series fixes a memory corruption bug in KHO that occurs when
KFENCE is enabled.
The root cause is that KHO metadata, allocated via kzalloc(), can be
randomly serviced by kfence_alloc(). When a kernel boots via KHO, the
early memblock allocator is restricted to a "scratch area". This forces
the KFENCE pool to be allocated within this scratch area, creating a
conflict. If KHO metadata is subsequently placed in this pool, it gets
corrupted during the next kexec operation.
[1] https://lore.kernel.org/all/20251007033100.836886-1-pasha.tatashin@soleen.c…
[2] https://lore.kernel.org/all/20251015053121.3978358-1-pasha.tatashin@soleen.…
Mike Rapoport (Microsoft) (1):
kho: drop notifiers
Pasha Tatashin (9):
kho: allow to drive kho from within kernel
kho: make debugfs interface optional
kho: add interfaces to unpreserve folios and page ranes
kho: don't unpreserve memory during abort
liveupdate: kho: move to kernel/liveupdate
kho: move kho debugfs directory to liveupdate
liveupdate: kho: warn and fail on metadata or preserved memory in
scratch area
liveupdate: kho: Increase metadata bitmap size to PAGE_SIZE
liveupdate: kho: allocate metadata directly from the buddy allocator
Documentation/core-api/kho/concepts.rst | 2 +-
MAINTAINERS | 3 +-
include/linux/kexec_handover.h | 53 +-
init/Kconfig | 2 +
kernel/Kconfig.kexec | 15 -
kernel/Makefile | 2 +-
kernel/liveupdate/Kconfig | 38 ++
kernel/liveupdate/Makefile | 5 +
kernel/{ => liveupdate}/kexec_handover.c | 588 +++++++++-----------
kernel/liveupdate/kexec_handover_debug.c | 25 +
kernel/liveupdate/kexec_handover_debugfs.c | 216 +++++++
kernel/liveupdate/kexec_handover_internal.h | 56 ++
lib/test_kho.c | 30 +-
mm/memblock.c | 62 +--
tools/testing/selftests/kho/init.c | 2 +-
tools/testing/selftests/kho/vmtest.sh | 1 +
16 files changed, 645 insertions(+), 455 deletions(-)
create mode 100644 kernel/liveupdate/Kconfig
create mode 100644 kernel/liveupdate/Makefile
rename kernel/{ => liveupdate}/kexec_handover.c (78%)
create mode 100644 kernel/liveupdate/kexec_handover_debug.c
create mode 100644 kernel/liveupdate/kexec_handover_debugfs.c
create mode 100644 kernel/liveupdate/kexec_handover_internal.h
base-commit: f406055cb18c6e299c4a783fc1effeb16be41803
--
2.51.0.915.g61a8936c21-goog
Hi all,
Now that the merge window is over, here's a respin of the previous
iteration rebased on the latest bpf-next_base. The bug triggering the
XDP_ADJUST_TAIL_SHRINK_MULTI_BUFF failure when CONFIG_DEBUG_VM is
enabled hasn't been fixed yet so I've moved the test to the flaky
table.
The test_xsk.sh script covers many AF_XDP use cases. The tests it runs
are defined in xksxceiver.c. Since this script is used to test real
hardware, the goal here is to leave it as it is, and only integrate the
tests that run on veth peers into the test_progs framework.
Some tests are flaky so they can't be integrated in the CI as they are.
I think that fixing their flakyness would require a significant amount of
work. So, as first step, I've excluded them from the list of tests
migrated to the CI (cf PATCH 14). If these tests get fixed at some
point, integrating them into the CI will be straightforward.
PATCH 1 extracts test_xsk[.c/.h] from xskxceiver[.c/.h] to make the
tests available to test_progs.
PATCH 2 to 7 fix small issues in the current test
PATCH 8 to 13 handle all errors to release resources instead of calling
exit() when any error occurs.
PATCH 14 isolates some flaky tests
PATCH 15 integrate the non-flaky tests to the test_progs framework
Signed-off-by: Bastien Curutchet (eBPF Foundation) <bastien.curutchet(a)bootlin.com>
---
Changes in v5:
- Rebase on latest bpf-next_base
- Move XDP_ADJUST_TAIL_SHRINK_MULTI_BUFF to the flaky table
- Add Maciej's reviewed-by
- Link to v4: https://lore.kernel.org/r/20250924-xsk-v4-0-20e57537b876@bootlin.com
Changes in v4:
- Fix test_xsk.sh's summary report.
- Merge PATCH 11 & 12 together, otherwise PATCH 11 fails to build.
- Split old PATCH 3 in two patches. The first one fixes
testapp_stats_rx_dropped(), the second one fixes
testapp_xdp_shared_umem(). The unecessary frees (in
testapp_stats_rx_full() and testapp_stats_fill_empty() are removed)
- Link to v3: https://lore.kernel.org/r/20250904-xsk-v3-0-ce382e331485@bootlin.com
Changes in v3:
- Rebase on latest bpf-next_base to integrate commit c9110e6f7237 ("selftests/bpf:
Fix count write in testapp_xdp_metadata_copy()").
- Move XDP_METADATA_COPY_* tests from flaky-tests to nominal tests
- Link to v2: https://lore.kernel.org/r/20250902-xsk-v2-0-17c6345d5215@bootlin.com
Changes in v2:
- Rebase on the latest bpf-next_base and integrate the newly added tests
to the work (adjust_tail* and tx_queue_consumer tests)
- Re-order patches to split xkxceiver sooner.
- Fix the bug reported by Maciej.
- Fix verbose mode in test_xsk.sh by keeping kselftest (remove PATCH 1,
7 and 8)
- Link to v1: https://lore.kernel.org/r/20250313-xsk-v1-0-7374729a93b9@bootlin.com
---
Bastien Curutchet (eBPF Foundation) (15):
selftests/bpf: test_xsk: Split xskxceiver
selftests/bpf: test_xsk: Initialize bitmap before use
selftests/bpf: test_xsk: Fix __testapp_validate_traffic()'s return value
selftests/bpf: test_xsk: fix memory leak in testapp_stats_rx_dropped()
selftests/bpf: test_xsk: fix memory leak in testapp_xdp_shared_umem()
selftests/bpf: test_xsk: Wrap test clean-up in functions
selftests/bpf: test_xsk: Release resources when swap fails
selftests/bpf: test_xsk: Add return value to init_iface()
selftests/bpf: test_xsk: Don't exit immediately when xsk_attach fails
selftests/bpf: test_xsk: Don't exit immediately when gettimeofday fails
selftests/bpf: test_xsk: Don't exit immediately when workers fail
selftests/bpf: test_xsk: Don't exit immediately if validate_traffic fails
selftests/bpf: test_xsk: Don't exit immediately on allocation failures
selftests/bpf: test_xsk: Isolate flaky tests
selftests/bpf: test_xsk: Integrate test_xsk.c to test_progs framework
tools/testing/selftests/bpf/Makefile | 11 +-
tools/testing/selftests/bpf/prog_tests/test_xsk.c | 2595 ++++++++++++++++++++
tools/testing/selftests/bpf/prog_tests/test_xsk.h | 294 +++
tools/testing/selftests/bpf/prog_tests/xsk.c | 146 ++
tools/testing/selftests/bpf/xskxceiver.c | 2696 +--------------------
tools/testing/selftests/bpf/xskxceiver.h | 156 --
6 files changed, 3174 insertions(+), 2724 deletions(-)
---
base-commit: bd61720310e0b11bfbb7c8e1f373bb87d98451d4
change-id: 20250218-xsk-0cf90e975d14
Best regards,
--
Bastien Curutchet (eBPF Foundation) <tux(a)bootlin.com>
The current KUnit documentation does not mention the kunit.enable
kernel parameter, making it unclear how to troubleshoot cases where
KUnit tests do not run as expected.
Add a note explaining kunit.enable parmaeter. Disabling this parameter
prevents all KUnit tests from running even if CONFIG_KUNIT is enabled.
Signed-off-by: Yuya Ishikawa <ishikawa.yuy-00(a)jp.fujitsu.com>
---
Documentation/dev-tools/kunit/run_manual.rst | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/Documentation/dev-tools/kunit/run_manual.rst b/Documentation/dev-tools/kunit/run_manual.rst
index 699d92885075..98e8d5b28808 100644
--- a/Documentation/dev-tools/kunit/run_manual.rst
+++ b/Documentation/dev-tools/kunit/run_manual.rst
@@ -35,6 +35,12 @@ or be built into the kernel.
a good way of quickly testing everything applicable to the current
config.
+ KUnit can be enabled or disabled at boot time, and this behavior is
+ controlled by the kunit.enable kernel parameter.
+ By default, kunit.enable is set to 1 because KUNIT_DEFAULT_ENABLED is
+ enabled by default. To ensure that tests are executed as expected,
+ verify that kunit.enable=1 at boot time.
+
Once we have built our kernel (and/or modules), it is simple to run
the tests. If the tests are built-in, they will run automatically on the
kernel boot. The results will be written to the kernel log (``dmesg``)
--
2.47.3