Since commit 31158ad02ddb ("rqspinlock: Add deadlock detection
and recovery") the updated path on re-entrancy now reports deadlock
via -EDEADLK instead of the previous -EBUSY.
Also, the way reentrancy was exercised (via fentry/lookup_elem_raw)
has been fragile because lookup_elem_raw may be inlined
(find_kernel_btf_id() will return -ESRCH).
To fix this fentry is attached to bpf_obj_free_fields() instead of
lookup_elem_raw() and:
- The htab map is made to use a BTF-described struct val with a
struct bpf_timer so that check_and_free_fields() reliably calls
bpf_obj_free_fields() on element replacement.
- The selftest is updated to do two updates to the same key (insert +
replace) in prog_test.
- The selftest is updated to align with expected errno with the
kernel’s current behavior.
Signed-off-by: Saket Kumar Bhaskar <skb99(a)linux.ibm.com>
---
Changes since v2:
Addressed CI failures:
* Initialize key to 0 before the first update.
* Used pointer value to pass for update and memset rather than
&value.
v2: https://lore.kernel.org/all/20251114152653.356782-1-skb99@linux.ibm.com/
Changes since v1:
Addressed comments from Alexei:
* Fixed the scenario where test may fail when lookup_elem_raw()
is inlined.
v1: https://lore.kernel.org/all/20251106052628.349117-1-skb99@linux.ibm.com/
.../selftests/bpf/prog_tests/htab_update.c | 37 ++++++++++++++-----
.../testing/selftests/bpf/progs/htab_update.c | 19 +++++++---
2 files changed, 41 insertions(+), 15 deletions(-)
diff --git a/tools/testing/selftests/bpf/prog_tests/htab_update.c b/tools/testing/selftests/bpf/prog_tests/htab_update.c
index 2bc85f4814f4..d0b405eb2966 100644
--- a/tools/testing/selftests/bpf/prog_tests/htab_update.c
+++ b/tools/testing/selftests/bpf/prog_tests/htab_update.c
@@ -15,17 +15,17 @@ struct htab_update_ctx {
static void test_reenter_update(void)
{
struct htab_update *skel;
- unsigned int key, value;
+ void *value = NULL;
+ unsigned int key, value_size;
int err;
skel = htab_update__open();
if (!ASSERT_OK_PTR(skel, "htab_update__open"))
return;
- /* lookup_elem_raw() may be inlined and find_kernel_btf_id() will return -ESRCH */
- bpf_program__set_autoload(skel->progs.lookup_elem_raw, true);
+ bpf_program__set_autoload(skel->progs.bpf_obj_free_fields, true);
err = htab_update__load(skel);
- if (!ASSERT_TRUE(!err || err == -ESRCH, "htab_update__load") || err)
+ if (!ASSERT_TRUE(!err, "htab_update__load") || err)
goto out;
skel->bss->pid = getpid();
@@ -33,14 +33,33 @@ static void test_reenter_update(void)
if (!ASSERT_OK(err, "htab_update__attach"))
goto out;
- /* Will trigger the reentrancy of bpf_map_update_elem() */
+ value_size = bpf_map__value_size(skel->maps.htab);
+
+ value = calloc(1, value_size);
+ if (!ASSERT_OK_PTR(value, "calloc value"))
+ goto out;
+ /*
+ * First update: plain insert. This should NOT trigger the re-entrancy
+ * path, because there is no old element to free yet.
+ */
key = 0;
- value = 0;
- err = bpf_map_update_elem(bpf_map__fd(skel->maps.htab), &key, &value, 0);
- if (!ASSERT_OK(err, "add element"))
+ err = bpf_map_update_elem(bpf_map__fd(skel->maps.htab), &key, value, BPF_ANY);
+ if (!ASSERT_OK(err, "first update (insert)"))
+ goto out;
+
+ /*
+ * Second update: replace existing element with same key and trigger
+ * the reentrancy of bpf_map_update_elem().
+ * check_and_free_fields() calls bpf_obj_free_fields() on the old
+ * value, which is where fentry program runs and performs a nested
+ * bpf_map_update_elem(), triggering -EDEADLK.
+ */
+ memset(value, 0, value_size);
+ err = bpf_map_update_elem(bpf_map__fd(skel->maps.htab), &key, value, BPF_ANY);
+ if (!ASSERT_OK(err, "second update (replace)"))
goto out;
- ASSERT_EQ(skel->bss->update_err, -EBUSY, "no reentrancy");
+ ASSERT_EQ(skel->bss->update_err, -EDEADLK, "no reentrancy");
out:
htab_update__destroy(skel);
}
diff --git a/tools/testing/selftests/bpf/progs/htab_update.c b/tools/testing/selftests/bpf/progs/htab_update.c
index 7481bb30b29b..195d3b2fba00 100644
--- a/tools/testing/selftests/bpf/progs/htab_update.c
+++ b/tools/testing/selftests/bpf/progs/htab_update.c
@@ -6,24 +6,31 @@
char _license[] SEC("license") = "GPL";
+/* Map value type: has BTF-managed field (bpf_timer) */
+struct val {
+ struct bpf_timer t;
+ __u64 payload;
+};
+
struct {
__uint(type, BPF_MAP_TYPE_HASH);
__uint(max_entries, 1);
- __uint(key_size, sizeof(__u32));
- __uint(value_size, sizeof(__u32));
+ __type(key, __u32);
+ __type(value, struct val);
} htab SEC(".maps");
int pid = 0;
int update_err = 0;
-SEC("?fentry/lookup_elem_raw")
-int lookup_elem_raw(void *ctx)
+SEC("?fentry/bpf_obj_free_fields")
+int bpf_obj_free_fields(void *ctx)
{
- __u32 key = 0, value = 1;
+ __u32 key = 0;
+ struct val value = { .payload = 1 };
if ((bpf_get_current_pid_tgid() >> 32) != pid)
return 0;
- update_err = bpf_map_update_elem(&htab, &key, &value, 0);
+ update_err = bpf_map_update_elem(&htab, &key, &value, BPF_ANY);
return 0;
}
--
2.51.0
In cgroup v2, a mutual overlap check is required when at least one of two
cpusets is exclusive. However, this check should be relaxed and limited to
cases where both cpusets are exclusive.
This patch ensures that for sibling cpusets A1 (exclusive) and B1
(non-exclusive), change B1 cannot affect A1's exclusivity.
for example. Assume a machine has 4 CPUs (0-3).
root cgroup
/ \
A1 B1
Case 1:
Table 1.1: Before applying the patch
Step | A1's prstate | B1'sprstate |
#1> echo "0-1" > A1/cpuset.cpus | member | member |
#2> echo "root" > A1/cpuset.cpus.partition | root | member |
#3> echo "0" > B1/cpuset.cpus | root invalid | member |
After step #3, A1 changes from "root" to "root invalid" because its CPUs
(0-1) overlap with those requested by B1 (0-3). However, B1 can actually
use CPUs 2-3(from B1's parent), so it would be more reasonable for A1 to
remain as "root."
Table 1.2: After applying the patch
Step | A1's prstate | B1'sprstate |
#1> echo "0-1" > A1/cpuset.cpus | member | member |
#2> echo "root" > A1/cpuset.cpus.partition | root | member |
#3> echo "0" > B1/cpuset.cpus | root | member |
Case 2: (This situation remains unchanged from before)
Table 2.1: Before applying the patch
Step | A1's prstate | B1'sprstate |
#1> echo "0-1" > A1/cpuset.cpus | member | member |
#3> echo "1-2" > B1/cpuset.cpus | member | member |
#2> echo "root" > A1/cpuset.cpus.partition | root invalid | member |
Table 2.2: After applying the patch
Step | A1's prstate | B1'sprstate |
#1> echo "0-1" > A1/cpuset.cpus | member | member |
#3> echo "1-2" > B1/cpuset.cpus | member | member |
#2> echo "root" > A1/cpuset.cpus.partition | root invalid | member |
All other cases remain unaffected. For example, cgroup-v1, both A1 and
B1 are exclusive or non-exlusive.
---
v3 -> v4:
- Adjust the test_cpuset_prt.sh test file to align with the current
behavior.
v2 -> v3:
- Ensure compliance with constraints such as cpuset.cpus.exclusive.
- Link: https://lore.kernel.org/cgroups/20251113131434.606961-1-sunshaojie@kylinos.…
v1 -> v2:
- Keeps the current cgroup v1 behavior unchanged
- Link: https://lore.kernel.org/cgroups/c8e234f4-2c27-4753-8f39-8ae83197efd3@redhat…
---
kernel/cgroup/cpuset-internal.h | 3 ++
kernel/cgroup/cpuset-v1.c | 20 +++++++++
kernel/cgroup/cpuset.c | 43 ++++++++++++++-----
.../selftests/cgroup/test_cpuset_prs.sh | 5 ++-
4 files changed, 58 insertions(+), 13 deletions(-)
--
2.25.1
I've removed the RFC tag from this version of the series, but the items
that I'm looking for feedback on remains the same:
- The userspace ABI, in particular:
- The vector length used for the SVE registers, access to the SVE
registers and access to ZA and (if available) ZT0 depending on
the current state of PSTATE.{SM,ZA}.
- The use of a single finalisation for both SVE and SME.
- The addition of control for enabling fine grained traps in a similar
manner to FGU but without the UNDEF, I'm not clear if this is desired
at all and at present this requires symmetric read and write traps like
FGU. That seemed like it might be desired from an implementation
point of view but we already have one case where we enable an
asymmetric trap (for ARM64_WORKAROUND_AMPERE_AC03_CPU_38) and it
seems generally useful to enable asymmetrically.
This series implements support for SME use in non-protected KVM guests.
Much of this is very similar to SVE, the main additional challenge that
SME presents is that it introduces a new vector length similar to the
SVE vector length and two new controls which change the registers seen
by guests:
- PSTATE.ZA enables the ZA matrix register and, if SME2 is supported,
the ZT0 LUT register.
- PSTATE.SM enables streaming mode, a new floating point mode which
uses the SVE register set with the separately configured SME vector
length. In streaming mode implementation of the FFR register is
optional.
It is also permitted to build systems which support SME without SVE, in
this case when not in streaming mode no SVE registers or instructions
are available. Further, there is no requirement that there be any
overlap in the set of vector lengths supported by SVE and SME in a
system, this is expected to be a common situation in practical systems.
Since there is a new vector length to configure we introduce a new
feature parallel to the existing SVE one with a new pseudo register for
the streaming mode vector length. Due to the overlap with SVE caused by
streaming mode rather than finalising SME as a separate feature we use
the existing SVE finalisation to also finalise SME, a new define
KVM_ARM_VCPU_VEC is provided to help make user code clearer. Finalising
SVE and SME separately would introduce complication with register access
since finalising SVE makes the SVE registers writeable by userspace and
doing multiple finalisations results in an error being reported.
Dealing with a state where the SVE registers are writeable due to one of
SVE or SME being finalised but may have their VL changed by the other
being finalised seems like needless complexity with minimal practical
utility, it seems clearer to just express directly that only one
finalisation can be done in the ABI.
Access to the floating point registers follows the architecture:
- When both SVE and SME are present:
- If PSTATE.SM == 0 the vector length used for the Z and P registers
is the SVE vector length.
- If PSTATE.SM == 1 the vector length used for the Z and P registers
is the SME vector length.
- If only SME is present:
- If PSTATE.SM == 0 the Z and P registers are inaccessible and the
floating point state accessed via the encodings for the V registers.
- If PSTATE.SM == 1 the vector length used for the Z and P registers
- The SME specific ZA and ZT0 registers are only accessible if SVCR.ZA is 1.
The VMM must understand this, in particular when loading state SVCR
should be configured before other state. It should be noted that while
the architecture refers to PSTATE.SM and PSTATE.ZA these PSTATE bits are
not preserved in SPSR_ELx, they are only accessible via SVCR.
There are a large number of subfeatures for SME, most of which only
offer additional instructions but some of which (SME2 and FA64) add
architectural state. These are configured via the ID registers as per
usual.
Protected KVM supported, with the implementation maintaining the
existing restriction that the hypervisor will refuse to run if streaming
mode or ZA is enabled. This both simplfies the code and avoids the need
to allocate storage for host ZA and ZT0 state, there seems to be little
practical use case for supporting this and the memory usage would be
non-trivial.
The new KVM_ARM_VCPU_VEC feature and ZA and ZT0 registers have not been
added to the get-reg-list selftest, the idea of supporting additional
features there without restructuring the program to generate all
possible feature combinations has been rejected. I will post a separate
series which does that restructuring.
Signed-off-by: Mark Brown <broonie(a)kernel.org>
---
Changes in v8:
- Small fixes in ABI documentation.
- Link to v7: https://lore.kernel.org/r/20250822-kvm-arm64-sme-v7-0-7a65d82b8b10@kernel.o…
Changes in v7:
- Rebase onto v6.17-rc1.
- Handle SMIDR_EL1 as a VM wide ID register and use this in feat_sme_smps().
- Expose affinity fields in SMIDR_EL1.
- Remove SMPRI_EL1 from vcpu_sysreg, the value is always 0 currently.
- Prevent userspace writes to SMPRIMAP_EL2.
- Link to v6: https://lore.kernel.org/r/20250625-kvm-arm64-sme-v6-0-114cff4ffe04@kernel.o…
Changes in v6:
- Rebase onto v6.16-rc3.
- Link to v5: https://lore.kernel.org/r/20250417-kvm-arm64-sme-v5-0-f469a2d5f574@kernel.o…
Changes in v5:
- Rebase onto v6.15-rc2.
- Add pKVM guest support.
- Always restore SVCR.
- Link to v4: https://lore.kernel.org/r/20250214-kvm-arm64-sme-v4-0-d64a681adcc2@kernel.o…
Changes in v4:
- Rebase onto v6.14-rc2 and Mark Rutland's fixes.
- Expose SME to nested guests.
- Additional cleanups and test fixes following on from the rebase.
- Flush register state on VMM PSTATE.{SM,ZA}.
- Link to v3: https://lore.kernel.org/r/20241220-kvm-arm64-sme-v3-0-05b018c1ffeb@kernel.o…
Changes in v3:
- Rebase onto v6.12-rc2.
- Link to v2: https://lore.kernel.org/r/20231222-kvm-arm64-sme-v2-0-da226cb180bb@kernel.o…
Changes in v2:
- Rebase onto v6.7-rc3.
- Configure subfeatures based on host system only.
- Complete nVHE support.
- There was some snafu with sending v1 out, it didn't make it to the
lists but in case it hit people's inboxes I'm sending as v2.
---
Mark Brown (29):
arm64/sysreg: Update SMIDR_EL1 to DDI0601 2025-06
arm64/fpsimd: Update FA64 and ZT0 enables when loading SME state
arm64/fpsimd: Decide to save ZT0 and streaming mode FFR at bind time
arm64/fpsimd: Check enable bit for FA64 when saving EFI state
arm64/fpsimd: Determine maximum virtualisable SME vector length
KVM: arm64: Introduce non-UNDEF FGT control
KVM: arm64: Pay attention to FFR parameter in SVE save and load
KVM: arm64: Pull ctxt_has_ helpers to start of sysreg-sr.h
KVM: arm64: Move SVE state access macros after feature test macros
KVM: arm64: Rename SVE finalization constants to be more general
KVM: arm64: Document the KVM ABI for SME
KVM: arm64: Define internal features for SME
KVM: arm64: Rename sve_state_reg_region
KVM: arm64: Store vector lengths in an array
KVM: arm64: Implement SME vector length configuration
KVM: arm64: Support SME control registers
KVM: arm64: Support TPIDR2_EL0
KVM: arm64: Support SME identification registers for guests
KVM: arm64: Support SME priority registers
KVM: arm64: Provide assembly for SME register access
KVM: arm64: Support userspace access to streaming mode Z and P registers
KVM: arm64: Flush register state on writes to SVCR.SM and SVCR.ZA
KVM: arm64: Expose SME specific state to userspace
KVM: arm64: Context switch SME state for guests
KVM: arm64: Handle SME exceptions
KVM: arm64: Expose SME to nested guests
KVM: arm64: Provide interface for configuring and enabling SME for guests
KVM: arm64: selftests: Add SME system registers to get-reg-list
KVM: arm64: selftests: Add SME to set_id_regs test
Documentation/virt/kvm/api.rst | 115 ++++++++---
arch/arm64/include/asm/fpsimd.h | 26 +++
arch/arm64/include/asm/kvm_emulate.h | 6 +
arch/arm64/include/asm/kvm_host.h | 169 ++++++++++++---
arch/arm64/include/asm/kvm_hyp.h | 5 +-
arch/arm64/include/asm/kvm_pkvm.h | 2 +-
arch/arm64/include/asm/vncr_mapping.h | 2 +
arch/arm64/include/uapi/asm/kvm.h | 33 +++
arch/arm64/kernel/cpufeature.c | 2 -
arch/arm64/kernel/fpsimd.c | 89 ++++----
arch/arm64/kvm/arm.c | 10 +
arch/arm64/kvm/config.c | 8 +-
arch/arm64/kvm/fpsimd.c | 28 ++-
arch/arm64/kvm/guest.c | 252 ++++++++++++++++++++---
arch/arm64/kvm/handle_exit.c | 14 ++
arch/arm64/kvm/hyp/fpsimd.S | 28 ++-
arch/arm64/kvm/hyp/include/hyp/switch.h | 175 ++++++++++++++--
arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h | 110 ++++++----
arch/arm64/kvm/hyp/nvhe/hyp-main.c | 86 ++++++--
arch/arm64/kvm/hyp/nvhe/pkvm.c | 85 ++++++--
arch/arm64/kvm/hyp/nvhe/switch.c | 4 +-
arch/arm64/kvm/hyp/nvhe/sys_regs.c | 6 +
arch/arm64/kvm/hyp/vhe/switch.c | 17 +-
arch/arm64/kvm/hyp/vhe/sysreg-sr.c | 7 +
arch/arm64/kvm/nested.c | 3 +-
arch/arm64/kvm/reset.c | 156 ++++++++++----
arch/arm64/kvm/sys_regs.c | 141 ++++++++++++-
arch/arm64/tools/sysreg | 8 +-
include/uapi/linux/kvm.h | 1 +
tools/testing/selftests/kvm/arm64/get-reg-list.c | 15 +-
tools/testing/selftests/kvm/arm64/set_id_regs.c | 27 ++-
31 files changed, 1327 insertions(+), 303 deletions(-)
---
base-commit: 062b3e4a1f880f104a8d4b90b767788786aa7b78
change-id: 20230301-kvm-arm64-sme-06a1246d3636
Best regards,
--
Mark Brown <broonie(a)kernel.org>
This patch set introduces the BPF_F_CPU and BPF_F_ALL_CPUS flags for
percpu maps, as the requirement of BPF_F_ALL_CPUS flag for percpu_array
maps was discussed in the thread of
"[PATCH bpf-next v3 0/4] bpf: Introduce global percpu data"[1].
The goal of BPF_F_ALL_CPUS flag is to reduce data caching overhead in light
skeletons by allowing a single value to be reused to update values across all
CPUs. This avoids the M:N problem where M cached values are used to update a
map on N CPUs kernel.
The BPF_F_CPU flag is accompanied by *flags*-embedded cpu info, which
specifies the target CPU for the operation:
* For lookup operations: the flag field alongside cpu info enable querying
a value on the specified CPU.
* For update operations: the flag field alongside cpu info enable
updating value for specified CPU.
Links:
[1] https://lore.kernel.org/bpf/20250526162146.24429-1-leon.hwang@linux.dev/
Changes:
v9 -> v10:
* Add tests to verify array and hash maps do not support BPF_F_CPU and
BPF_F_ALL_CPUS flags.
* Address comment from Andrii:
* Copy map value using copy_map_value_long for percpu_cgroup_storage
maps in a separate patch.
v8 -> v9:
* Change value type from u64 to u32 in selftests.
* Address comments from Andrii:
* Keep value_size unaligned and update everywhere for consistency when
cpu flags are specified.
* Update value by getting pointer for percpu hash and percpu
cgroup_storage maps.
v7 -> v8:
* Address comments from Andrii:
* Check BPF_F_LOCK when update percpu_array, percpu_hash and
lru_percpu_hash maps.
* Refactor flags check in __htab_map_lookup_and_delete_batch().
* Keep value_size unaligned and copy value using copy_map_value() in
__htab_map_lookup_and_delete_batch() when BPF_F_CPU is specified.
* Update warn message in libbpf's validate_map_op().
* Update comment of libbpf's bpf_map__lookup_elem().
v6 -> v7:
* Get correct value size for percpu_hash and lru_percpu_hash in
update_batch API.
* Set 'count' as 'max_entries' in test cases for lookup_batch API.
* Address comment from Alexei:
* Move cpu flags check into bpf_map_check_op_flags().
v5 -> v6:
* Move bpf_map_check_op_flags() from 'bpf.h' to 'syscall.c'.
* Address comments from Alexei:
* Drop the refactoring code of data copying logic for percpu maps.
* Drop bpf_map_check_op_flags() wrappers.
v4 -> v5:
* Address comments from Andrii:
* Refactor data copying logic for all percpu maps.
* Drop this_cpu_ptr() micro-optimization.
* Drop cpu check in libbpf's validate_map_op().
* Enhance bpf_map_check_op_flags() using *allowed flags* instead of
'extra_flags_mask'.
v3 -> v4:
* Address comments from Andrii:
* Remove unnecessary map_type check in bpf_map_value_size().
* Reduce code churn.
* Remove unnecessary do_delete check in
__htab_map_lookup_and_delete_batch().
* Introduce bpf_percpu_copy_to_user() and bpf_percpu_copy_from_user().
* Rename check_map_flags() to bpf_map_check_op_flags() with
extra_flags_mask.
* Add human-readable pr_warn() explanations in validate_map_op().
* Use flags in bpf_map__delete_elem() and
bpf_map__lookup_and_delete_elem().
* Drop "for alignment reasons".
v3 link: https://lore.kernel.org/bpf/20250821160817.70285-1-leon.hwang@linux.dev/
v2 -> v3:
* Address comments from Alexei:
* Use BPF_F_ALL_CPUS instead of BPF_ALL_CPUS magic.
* Introduce these two cpu flags for all percpu maps.
* Address comments from Jiri:
* Reduce some unnecessary u32 cast.
* Refactor more generic map flags check function.
* A code style issue.
v2 link: https://lore.kernel.org/bpf/20250805163017.17015-1-leon.hwang@linux.dev/
v1 -> v2:
* Address comments from Andrii:
* Embed cpu info as high 32 bits of *flags* totally.
* Use ERANGE instead of E2BIG.
* Few format issues.
Leon Hwang (8):
bpf: Introduce internal bpf_map_check_op_flags helper function
bpf: Introduce BPF_F_CPU and BPF_F_ALL_CPUS flags
bpf: Add BPF_F_CPU and BPF_F_ALL_CPUS flags support for percpu_array
maps
bpf: Add BPF_F_CPU and BPF_F_ALL_CPUS flags support for percpu_hash
and lru_percpu_hash maps
bpf: Copy map value using copy_map_value_long for
percpu_cgroup_storage maps
bpf: Add BPF_F_CPU and BPF_F_ALL_CPUS flags support for
percpu_cgroup_storage maps
libbpf: Add BPF_F_CPU and BPF_F_ALL_CPUS flags support for percpu maps
selftests/bpf: Add cases to test BPF_F_CPU and BPF_F_ALL_CPUS flags
include/linux/bpf-cgroup.h | 4 +-
include/linux/bpf.h | 44 ++-
include/uapi/linux/bpf.h | 2 +
kernel/bpf/arraymap.c | 29 +-
kernel/bpf/hashtab.c | 94 ++++--
kernel/bpf/local_storage.c | 27 +-
kernel/bpf/syscall.c | 65 ++--
tools/include/uapi/linux/bpf.h | 2 +
tools/lib/bpf/bpf.h | 8 +
tools/lib/bpf/libbpf.c | 26 +-
tools/lib/bpf/libbpf.h | 21 +-
.../selftests/bpf/prog_tests/percpu_alloc.c | 312 ++++++++++++++++++
.../selftests/bpf/progs/percpu_alloc_array.c | 32 ++
13 files changed, 562 insertions(+), 104 deletions(-)
--
2.51.2
From: Jack Thomson <jackabt(a)amazon.com>
This patch series adds ARM64 support for the KVM_PRE_FAULT_MEMORY
feature, which was previously only available on x86 [1]. This allows us
to reduce the number of stage-2 faults during execution. This is of
benefit in post-copy migration scenarios, particularly in memory
intensive applications, where we are experiencing high latencies due to
the stage-2 faults.
Patch Overview:
- The first patch adds support for the KVM_PRE_FAULT_MEMORY ioctl
on arm64.
- The second patch updates the pre_fault_memory_test to support
arm64.
- The last patch extends the pre_fault_memory_test to cover
different vm memory backings.
=== Changes Since v2 [2] ===
- Update fault info synthesize value. Thanks Suzuki
- Remove change to selftests for unaligned mmap allocations. Thanks
Sean
[1]: https://lore.kernel.org/kvm/20240710174031.312055-1-pbonzini@redhat.com
[2]: https://lore.kernel.org/linux-arm-kernel/20251013151502.6679-1-jackabt.amaz…
Jack Thomson (3):
KVM: arm64: Add pre_fault_memory implementation
KVM: selftests: Enable pre_fault_memory_test for arm64
KVM: selftests: Add option for different backing in pre-fault tests
Documentation/virt/kvm/api.rst | 3 +-
arch/arm64/kvm/Kconfig | 1 +
arch/arm64/kvm/arm.c | 1 +
arch/arm64/kvm/mmu.c | 73 +++++++++++-
tools/testing/selftests/kvm/Makefile.kvm | 1 +
.../selftests/kvm/pre_fault_memory_test.c | 110 ++++++++++++++----
6 files changed, 159 insertions(+), 30 deletions(-)
base-commit: 8a4821412cf2c1429fffa07c012dd150f2edf78c
--
2.43.0
Hi all,
This patch series introduces improvements to the cgroup selftests by adding helper functions to better handle
asynchronous updates in cgroup statistics. These changes are especially useful for managing cgroup stats like
memory.stat and cgroup.stat, which can be affected by delays (e.g., RCPU callbacks and asynchronous rstat flushing).
v4:
- Patch 1/3: Adds the `cg_read_key_long_poll()` helper to poll cgroup keys with retries and configurable intervals.
- Patch 2/3: Updates `test_memcg_sock()` to use `cg_read_key_long_poll()` for handling delayed "sock" counter updates in memory.stat.
- Patch 3/3: Replaces `sleep` and retry logic in `test_kmem_dead_cgroups()` with `cg_read_key_long_poll()` for waiting on `nr_dying_descendants`.
v3:
- Move `MEMCG_SOCKSTAT_WAIT_*` defines after the `#include` block as suggested.
v2:
- Clarify the rationale for the 3s timeout and mention the periodic rstat flush interval (FLUSH_TIME = 2*HZ) in the comment.
- Replace hardcoded retry count and wait interval with macros to avoid magic numbers and make the timeout calculation explicit.
Thanks to Michal Koutný for the suggestion to introduce the polling helper, and to Lance Yang for the review.
Guopeng Zhang (3):
selftests: cgroup: Add cg_read_key_long_poll() to poll a cgroup key
with retries
selftests: cgroup: make test_memcg_sock robust against delayed sock
stats
selftests: cgroup: Replace sleep with cg_read_key_long_poll() for
waiting on nr_dying_descendants
.../selftests/cgroup/lib/cgroup_util.c | 21 +++++++++++++
.../cgroup/lib/include/cgroup_util.h | 5 +++
tools/testing/selftests/cgroup/test_kmem.c | 31 ++++++++-----------
.../selftests/cgroup/test_memcontrol.c | 20 +++++++++++-
4 files changed, 58 insertions(+), 19 deletions(-)
--
2.25.1
This series adds support for tests that use multiple devices, and adds
one new test, vfio_pci_device_init_perf_test, which measures parallel
device initialization time to demonstrate the improvement from commit
e908f58b6beb ("vfio/pci: Separate SR-IOV VF dev_set").
This series also breaks apart the monolithic vfio_util.h and
vfio_pci_device.c into separate files, to account for all the new code.
This required quite a bit of code motion so the diffstat looks large.
The final layout is more granular and provides a better separation of
the IOMMU code from the device code.
Final layout:
C files:
- tools/testing/selftests/vfio/lib/libvfio.c
- tools/testing/selftests/vfio/lib/iommu.c
- tools/testing/selftests/vfio/lib/iova_allocator.c
- tools/testing/selftests/vfio/lib/vfio_pci_device.c
- tools/testing/selftests/vfio/lib/vfio_pci_driver.c
H files:
- tools/testing/selftests/vfio/lib/include/libvfio.h
- tools/testing/selftests/vfio/lib/include/libvfio/assert.h
- tools/testing/selftests/vfio/lib/include/libvfio/iommu.h
- tools/testing/selftests/vfio/lib/include/libvfio/iova_allocator.h
- tools/testing/selftests/vfio/lib/include/libvfio/vfio_pci_device.h
- tools/testing/selftests/vfio/lib/include/libvfio/vfio_pci_driver.h
Notably, vfio_util.h is now gone and replaced with libvfio.h.
This series is based on vfio/next plus Alex Mastro's series to add the
IOVA allocator [1]. It should apply cleanly to vfio/next once Alex's
series is merged by Linus into the next 6.18 rc and then merged into
vfio/next.
This series can be found on GitHub:
https://github.com/dmatlack/linux/tree/vfio/selftests/init_perf_test/v3
[1] https://lore.kernel.org/kvm/20251111-iova-ranges-v3-0-7960244642c5@fb.com/
Cc: Alex Mastro <amastro(a)fb.com>
Cc: Jason Gunthorpe <jgg(a)nvidia.com>
Cc: Josh Hilke <jrhilke(a)google.com>
Cc: Raghavendra Rao Ananta <rananta(a)google.com>
Cc: Vipin Sharma <vipinsh(a)google.com>
v3:
- Replace literal with NSEC_PER_SEC (Alex Mastro)
- Fix Makefile accumulate vs. assignment (Alex Mastro)
v2: https://lore.kernel.org/kvm/20251112192232.442761-1-dmatlack@google.com/
v1: https://lore.kernel.org/kvm/20251008232531.1152035-1-dmatlack@google.com/
David Matlack (18):
vfio: selftests: Move run.sh into scripts directory
vfio: selftests: Split run.sh into separate scripts
vfio: selftests: Allow passing multiple BDFs on the command line
vfio: selftests: Rename struct vfio_iommu_mode to iommu_mode
vfio: selftests: Introduce struct iommu
vfio: selftests: Support multiple devices in the same
container/iommufd
vfio: selftests: Eliminate overly chatty logging
vfio: selftests: Prefix logs with device BDF where relevant
vfio: selftests: Upgrade driver logging to dev_err()
vfio: selftests: Rename struct vfio_dma_region to dma_region
vfio: selftests: Move IOMMU library code into iommu.c
vfio: selftests: Move IOVA allocator into iova_allocator.c
vfio: selftests: Stop passing device for IOMMU operations
vfio: selftests: Rename vfio_util.h to libvfio.h
vfio: selftests: Move vfio_selftests_*() helpers into libvfio.c
vfio: selftests: Split libvfio.h into separate header files
vfio: selftests: Eliminate INVALID_IOVA
vfio: selftests: Add vfio_pci_device_init_perf_test
tools/testing/selftests/vfio/Makefile | 10 +-
.../selftests/vfio/lib/drivers/dsa/dsa.c | 36 +-
.../selftests/vfio/lib/drivers/ioat/ioat.c | 18 +-
.../selftests/vfio/lib/include/libvfio.h | 26 +
.../vfio/lib/include/libvfio/assert.h | 54 ++
.../vfio/lib/include/libvfio/iommu.h | 76 +++
.../vfio/lib/include/libvfio/iova_allocator.h | 23 +
.../lib/include/libvfio/vfio_pci_device.h | 125 ++++
.../lib/include/libvfio/vfio_pci_driver.h | 97 +++
.../selftests/vfio/lib/include/vfio_util.h | 331 -----------
tools/testing/selftests/vfio/lib/iommu.c | 465 +++++++++++++++
.../selftests/vfio/lib/iova_allocator.c | 94 +++
tools/testing/selftests/vfio/lib/libvfio.c | 78 +++
tools/testing/selftests/vfio/lib/libvfio.mk | 5 +-
.../selftests/vfio/lib/vfio_pci_device.c | 555 +-----------------
.../selftests/vfio/lib/vfio_pci_driver.c | 16 +-
tools/testing/selftests/vfio/run.sh | 109 ----
.../testing/selftests/vfio/scripts/cleanup.sh | 41 ++
tools/testing/selftests/vfio/scripts/lib.sh | 42 ++
tools/testing/selftests/vfio/scripts/run.sh | 16 +
tools/testing/selftests/vfio/scripts/setup.sh | 48 ++
.../selftests/vfio/vfio_dma_mapping_test.c | 46 +-
.../selftests/vfio/vfio_iommufd_setup_test.c | 2 +-
.../vfio/vfio_pci_device_init_perf_test.c | 168 ++++++
.../selftests/vfio/vfio_pci_device_test.c | 12 +-
.../selftests/vfio/vfio_pci_driver_test.c | 51 +-
26 files changed, 1481 insertions(+), 1063 deletions(-)
create mode 100644 tools/testing/selftests/vfio/lib/include/libvfio.h
create mode 100644 tools/testing/selftests/vfio/lib/include/libvfio/assert.h
create mode 100644 tools/testing/selftests/vfio/lib/include/libvfio/iommu.h
create mode 100644 tools/testing/selftests/vfio/lib/include/libvfio/iova_allocator.h
create mode 100644 tools/testing/selftests/vfio/lib/include/libvfio/vfio_pci_device.h
create mode 100644 tools/testing/selftests/vfio/lib/include/libvfio/vfio_pci_driver.h
delete mode 100644 tools/testing/selftests/vfio/lib/include/vfio_util.h
create mode 100644 tools/testing/selftests/vfio/lib/iommu.c
create mode 100644 tools/testing/selftests/vfio/lib/iova_allocator.c
create mode 100644 tools/testing/selftests/vfio/lib/libvfio.c
delete mode 100755 tools/testing/selftests/vfio/run.sh
create mode 100755 tools/testing/selftests/vfio/scripts/cleanup.sh
create mode 100755 tools/testing/selftests/vfio/scripts/lib.sh
create mode 100755 tools/testing/selftests/vfio/scripts/run.sh
create mode 100755 tools/testing/selftests/vfio/scripts/setup.sh
create mode 100644 tools/testing/selftests/vfio/vfio_pci_device_init_perf_test.c
base-commit: fa804aa4ac1b091ef2ec2981f08a1c28aaeba8e7
prerequisite-patch-id: dcf23dcc1198960bda3102eefaa21df60b2e4c54
prerequisite-patch-id: e32e56d5bf7b6c7dd40d737aa3521560407e00f5
prerequisite-patch-id: 4f79a41bf10a4c025ba5f433551b46035aa15878
prerequisite-patch-id: f903a45f0c32319138cd93a007646ab89132b18c
--
2.52.0.rc2.455.g230fcf2819-goog
This patchset introduces target resume capability to netconsole allowing
it to recover targets when underlying low-level interface comes back
online.
The patchset starts by refactoring netconsole state representation in
order to allow representing deactivated targets (targets that are
disabled due to interfaces going down).
It then modifies netconsole to handle NETDEV_UP events for such targets
and setups netpoll. Targets are matched with incoming interfaces
depending on how they were initially bound in netconsole (by mac or
interface name).
The patchset includes a selftest that validates netconsole target state
transitions and that target is functional after resumed.
Signed-off-by: Andre Carvalho <asantostc(a)gmail.com>
---
Changes in v6:
- Rebase on top of net-next to resolve conflicts, no functional changes.
- Link to v5: https://lore.kernel.org/r/20251119-netcons-retrigger-v5-0-2c7dda6055d6@gmai…
Changes in v5:
- patch 3: Set (de)enslaved target as DISABLED instead of DEACTIVATED to prevent
resuming it.
- selftest: Fix test cleanup by moving trap line to outside of loop and remove
unneeded 'local' keyword
- Rename maybe_resume_target to resume_target, add netconsole_ prefix to
process_resumable_targets.
- Hold device reference before calling __netpoll_setup.
- Link to v4: https://lore.kernel.org/r/20251116-netcons-retrigger-v4-0-5290b5f140c2@gmai…
Changes in v4:
- Simplify selftest cleanup, removing trap setup in loop.
- Drop netpoll helper (__setup_netpoll_hold) and manage reference inside
netconsole.
- Move resume_list processing logic to separate function.
- Link to v3: https://lore.kernel.org/r/20251109-netcons-retrigger-v3-0-1654c280bbe6@gmai…
Changes in v3:
- Resume by mac or interface name depending on how target was created.
- Attempt to resume target without holding target list lock, by moving
the target to a temporary list. This is required as netpoll may
attempt to allocate memory.
- Link to v2: https://lore.kernel.org/r/20250921-netcons-retrigger-v2-0-a0e84006237f@gmai…
Changes in v2:
- Attempt to resume target in the same thread, instead of using
workqueue .
- Add wrapper around __netpoll_setup (patch 4).
- Renamed resume_target to maybe_resume_target and moved conditionals to
inside its implementation, keeping code more clear.
- Verify that device addr matches target mac address when target was
setup using mac.
- Update selftest to cover targets bound by mac and interface name.
- Fix typo in selftest comment and sort tests alphabetically in
Makefile.
- Link to v1:
https://lore.kernel.org/r/20250909-netcons-retrigger-v1-0-3aea904926cf@gmai…
---
Andre Carvalho (3):
netconsole: convert 'enabled' flag to enum for clearer state management
netconsole: resume previously deactivated target
selftests: netconsole: validate target resume
Breno Leitao (2):
netconsole: add target_state enum
netconsole: add STATE_DEACTIVATED to track targets disabled by low level
drivers/net/netconsole.c | 155 +++++++++++++++++----
tools/testing/selftests/drivers/net/Makefile | 1 +
.../selftests/drivers/net/lib/sh/lib_netcons.sh | 35 ++++-
.../selftests/drivers/net/netcons_resume.sh | 97 +++++++++++++
4 files changed, 254 insertions(+), 34 deletions(-)
---
base-commit: e2c20036a8879476c88002730d8a27f4e3c32d4b
change-id: 20250816-netcons-retrigger-a4f547bfc867
Best regards,
--
Andre Carvalho <asantostc(a)gmail.com>
In commit 0297cdc12a87 ("KVM: selftests: Add option to rseq test to
override /dev/cpu_dma_latency"), a 'break' is missed before the option
'l' in the argument parsing loop, which leads to an unexpected core
dump in atoi_paranoid(). It tries to get the latency from non-existent
argument.
host$ ./rseq_test -u
Random seed: 0x6b8b4567
Segmentation fault (core dumped)
Add a 'break' before the option 'l' in the argument parsing loop to avoid
the unexpected core dump.
Fixes: 0297cdc12a87 ("KVM: selftests: Add option to rseq test to override /dev/cpu_dma_latency")
Cc: stable(a)vger.kernel.org # v6.15+
Signed-off-by: Gavin Shan <gshan(a)redhat.com>
---
tools/testing/selftests/kvm/rseq_test.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/tools/testing/selftests/kvm/rseq_test.c b/tools/testing/selftests/kvm/rseq_test.c
index 1375fca80bcdb..f80ad6b47d16b 100644
--- a/tools/testing/selftests/kvm/rseq_test.c
+++ b/tools/testing/selftests/kvm/rseq_test.c
@@ -215,6 +215,7 @@ int main(int argc, char *argv[])
switch (opt) {
case 'u':
skip_sanity_check = true;
+ break;
case 'l':
latency = atoi_paranoid(optarg);
break;
--
2.51.1