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>
---
Changes in v4:
- Rebase onto arm64/for-next/cpufeature, note that both patches have
build dependencies on this.
- Drop unneeded cc clobber in hwcap.
- Use STRFADD as the instruction probed in hwcap.
- Link to v3: https://lore.kernel.org/r/20250818-arm64-lsfe-v3-0-af6f4d66eb39@kernel.org
Changes in v3:
- Rebase onto v6.17-rc1.
- Link to v2: https://lore.kernel.org/r/20250703-arm64-lsfe-v2-0-eced80999cb4@kernel.org
Changes in v2:
- Fix result of vi dropping in hwcap test.
- Link to v1: https://lore.kernel.org/r/20250627-arm64-lsfe-v1-0-68351c4bf741@kernel.org
---
Mark Brown (2):
KVM: arm64: Expose FEAT_LSFE to guests
kselftest/arm64: Add lsfe to the hwcaps test
arch/arm64/kvm/sys_regs.c | 4 +++-
tools/testing/selftests/arm64/abi/hwcap.c | 21 +++++++++++++++++++++
2 files changed, 24 insertions(+), 1 deletion(-)
---
base-commit: 220928e52cb03d223b3acad3888baf0687486d21
change-id: 20250625-arm64-lsfe-0810cf98adc2
Best regards,
--
Mark Brown <broonie(a)kernel.org>
This patch simplifies kublk's implementation of the feature list
command, fixes a bug where a feature was missing, and adds a test to
ensure that similar bugs do not happen in the future.
Signed-off-by: Uday Shankar <ushankar(a)purestorage.com>
---
Changes in v2:
- Add log lines to new test in failure case, to tell the user how to fix
the test, and to indicate that the failure is expected when running
an old test suite against a new kernel (Ming Lei)
- Link to v1: https://lore.kernel.org/r/20250916-ublk_features-v1-0-52014be9cde5@purestor…
---
Uday Shankar (3):
selftests: ublk: kublk: simplify feat_map definition
selftests: ublk: kublk: add UBLK_F_BUF_REG_OFF_DAEMON to feat_map
selftests: ublk: add test to verify that feat_map is complete
tools/testing/selftests/ublk/Makefile | 1 +
tools/testing/selftests/ublk/kublk.c | 32 +++++++++++++------------
tools/testing/selftests/ublk/test_generic_13.sh | 20 ++++++++++++++++
3 files changed, 38 insertions(+), 15 deletions(-)
---
base-commit: da7b97ba0d219a14a83e9cc93f98b53939f12944
change-id: 20250916-ublk_features-07af4e321e5a
Best regards,
--
Uday Shankar <ushankar(a)purestorage.com>
There is a spelling mistake in a test message. Fix it.
Signed-off-by: Colin Ian King <colin.i.king(a)gmail.com>
---
tools/testing/selftests/futex/functional/futex_numa_mpol.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/tools/testing/selftests/futex/functional/futex_numa_mpol.c b/tools/testing/selftests/futex/functional/futex_numa_mpol.c
index 722427fe90bf..3a71ab93db72 100644
--- a/tools/testing/selftests/futex/functional/futex_numa_mpol.c
+++ b/tools/testing/selftests/futex/functional/futex_numa_mpol.c
@@ -206,7 +206,7 @@ int main(int argc, char *argv[])
ksft_print_msg("Memory back to RW\n");
test_futex(futex_ptr, 0);
- ksft_test_result_pass("futex2 memory boundarie tests passed\n");
+ ksft_test_result_pass("futex2 memory boundary tests passed\n");
/* MPOL test. Does not work as expected */
#ifdef LIBNUMA_VER_SUFFICIENT
--
2.51.0
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>
Syzkaller found this, fput runs the release from a work queue so the
refcount remains elevated during abort. This is tricky so move more
handling of files into the core code.
Add a WARN_ON to catch things like this more reliably without relying on
kasn.
Update the fail_nth test to succeed on 6.17 kernels.
Jason Gunthorpe (3):
iommufd: Fix race during abort for file descriptors
iommufd: WARN if an object is aborted with an elevated refcount
iommufd/selftest: Update the fail_nth limit
drivers/iommu/iommufd/device.c | 3 +-
drivers/iommu/iommufd/eventq.c | 9 +----
drivers/iommu/iommufd/iommufd_private.h | 3 +-
drivers/iommu/iommufd/main.c | 39 +++++++++++++++++--
.../selftests/iommu/iommufd_fail_nth.c | 2 +-
5 files changed, 42 insertions(+), 14 deletions(-)
base-commit: 1046d40b0e78d2cd63f6183629699b629b21f877
--
2.43.0
Mshare is a developing feature proposed by Anthony Yznaga and Khalid Aziz
that enables sharing of PTEs across processes. The V3 patch set has been
posted for review:
https://lore.kernel.org/linux-mm/20250820010415.699353-1-anthony.yznaga@ora…
This patch set adds selftests to exercise and demonstrate basic
functionality of mshare.
The initial tests use open, ioctl, and mmap syscalls to establish a shared
memory mapping between two processes and verify the expected behavior.
Additional tests are included to check interoperability with swap and
Transparent Huge Pages.
Future work will extend coverage to other use cases such as integration
with KVM and more advanced scenarios.
This series is intended to be applied on top of mshare V3, which is
based on mm-new (2025-08-15).
-----------------
V1->V2:
- Based on mshare V3, which based on mm-new as of 2025-08-15
- (Fix) For test cases in basic.c, Change to use a small chunk of
memory(4k/8K for normal pages, 2M/4M for hugetlb pages), as to
ensure these tests can run on any server or device.
- (Fix) For test cases of hugetlb, swap and THP, add a tips to
configure corresponding settings.
- (Fix) Add memory to .gitignore file once it exists
- (fix) Correct the Changelog of THP test case that mshare support
THP only when user configure shmem_enabled as always
V1:
https://lore.kernel.org/all/20250825145719.29455-1-linyongting@bytedance.co…
Yongting Lin (8):
mshare: Add selftests
mshare: selftests: Adding config fragments
mshare: selftests: Add some helper functions for mshare filesystem
mshare: selftests: Add test case shared memory
mshare: selftests: Add test case ioctl unmap
mshare: selftests: Add some helper functions for configuring and
retrieving cgroup
mshare: selftests: Add test case to demostrate the swapping of mshare
memory
mshare: selftests: Add test case to demostrate that mshare partly
supports THP
tools/testing/selftests/mshare/.gitignore | 4 +
tools/testing/selftests/mshare/Makefile | 7 +
tools/testing/selftests/mshare/basic.c | 109 ++++++++++
tools/testing/selftests/mshare/config | 1 +
tools/testing/selftests/mshare/memory.c | 89 ++++++++
tools/testing/selftests/mshare/util.c | 254 ++++++++++++++++++++++
6 files changed, 464 insertions(+)
create mode 100644 tools/testing/selftests/mshare/.gitignore
create mode 100644 tools/testing/selftests/mshare/Makefile
create mode 100644 tools/testing/selftests/mshare/basic.c
create mode 100644 tools/testing/selftests/mshare/config
create mode 100644 tools/testing/selftests/mshare/memory.c
create mode 100644 tools/testing/selftests/mshare/util.c
--
2.20.1
For a while now we have supported file handles for pidfds. This has
proven to be very useful.
Extend the concept to cover namespaces as well. After this patchset it
is possible to encode and decode namespace file handles using the
commong name_to_handle_at() and open_by_handle_at() apis.
Namespaces file descriptors can already be derived from pidfds which
means they aren't subject to overmount protection bugs. IOW, it's
irrelevant if the caller would not have access to an appropriate
/proc/<pid>/ns/ directory as they could always just derive the namespace
based on a pidfd already.
It has the same advantage as pidfds. It's possible to reliably and for
the lifetime of the system refer to a namespace without pinning any
resources and to compare them.
Permission checking is kept simple. If the caller is located in the
namespace the file handle refers to they are able to open it otherwise
they must hold privilege over the owning namespace of the relevant
namespace.
Both the network namespace and the mount namespace already have an
associated cookie that isn't recycled and is fully exposed to userspace.
Move this into ns_common and use the same id space for all namespaces so
they can trivially and reliably be compared.
There's more coming based on the iterator infrastructure but the series
is large enough and focuses on file handles.
Extensive selftests included.
Signed-off-by: Christian Brauner <brauner(a)kernel.org>
---
Changes in v2:
- Address various review comments.
- Use a common NS_GET_ID ioctl() instead of individual ioctls.
- Link to v1: https://lore.kernel.org/20250910-work-namespace-v1-0-4dd56e7359d8@kernel.org
---
Christian Brauner (33):
pidfs: validate extensible ioctls
nsfs: drop tautological ioctl() check
nsfs: validate extensible ioctls
block: use extensible_ioctl_valid()
ns: move to_ns_common() to ns_common.h
nsfs: add nsfs.h header
ns: uniformly initialize ns_common
cgroup: use ns_common_init()
ipc: use ns_common_init()
mnt: use ns_common_init()
net: use ns_common_init()
pid: use ns_common_init()
time: use ns_common_init()
user: use ns_common_init()
uts: use ns_common_init()
ns: remove ns_alloc_inum()
nstree: make iterator generic
mnt: support ns lookup
cgroup: support ns lookup
ipc: support ns lookup
net: support ns lookup
pid: support ns lookup
time: support ns lookup
user: support ns lookup
uts: support ns lookup
ns: add to_<type>_ns() to respective headers
nsfs: add current_in_namespace()
nsfs: support file handles
nsfs: support exhaustive file handles
nsfs: add missing id retrieval support
tools: update nsfs.h uapi header
selftests/namespaces: add identifier selftests
selftests/namespaces: add file handle selftests
block/blk-integrity.c | 8 +-
fs/fhandle.c | 6 +
fs/internal.h | 1 +
fs/mount.h | 10 +-
fs/namespace.c | 156 +--
fs/nsfs.c | 201 ++-
fs/pidfs.c | 2 +-
include/linux/cgroup.h | 5 +
include/linux/exportfs.h | 6 +
include/linux/fs.h | 14 +
include/linux/ipc_namespace.h | 5 +
include/linux/ns_common.h | 29 +
include/linux/nsfs.h | 40 +
include/linux/nsproxy.h | 11 -
include/linux/nstree.h | 89 ++
include/linux/pid_namespace.h | 5 +
include/linux/proc_ns.h | 32 +-
include/linux/time_namespace.h | 9 +
include/linux/user_namespace.h | 5 +
include/linux/utsname.h | 5 +
include/net/net_namespace.h | 6 +
include/uapi/linux/fcntl.h | 1 +
include/uapi/linux/nsfs.h | 15 +-
init/main.c | 2 +
ipc/msgutil.c | 1 +
ipc/namespace.c | 12 +-
ipc/shm.c | 2 +
kernel/Makefile | 2 +-
kernel/cgroup/cgroup.c | 2 +
kernel/cgroup/namespace.c | 24 +-
kernel/nstree.c | 233 ++++
kernel/pid_namespace.c | 13 +-
kernel/time/namespace.c | 23 +-
kernel/user_namespace.c | 17 +-
kernel/utsname.c | 28 +-
net/core/net_namespace.c | 59 +-
tools/include/uapi/linux/nsfs.h | 17 +-
tools/testing/selftests/namespaces/.gitignore | 2 +
tools/testing/selftests/namespaces/Makefile | 7 +
tools/testing/selftests/namespaces/config | 7 +
.../selftests/namespaces/file_handle_test.c | 1429 ++++++++++++++++++++
tools/testing/selftests/namespaces/nsid_test.c | 986 ++++++++++++++
42 files changed, 3257 insertions(+), 270 deletions(-)
---
base-commit: 8f5ae30d69d7543eee0d70083daf4de8fe15d585
change-id: 20250905-work-namespace-c68826dda0d4
[ I think at this point everyone is OK with the ABI, and the x86
implementation has been tested so hopefully we are near to being
able to get this merged? If there are any outstanding issues let
me know and I can look at addressing them. The one possible issue
I am aware of is that the RISC-V shadow stack support was briefly
in -next but got dropped along with the general RISC-V issues during
the last merge window, rebasing for that is still in progress. I
guess ideally this could be applied on a branch and then pulled into
the RISC-V tree? ]
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). The idea has, however, had
strong pushback from the architecture maintainers and it is possible to
detect support for this in clone3() by attempting a call with a
misaligned shadow stack pointer specified so no hwcap has been added.
[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 v21:
- Rebase onto https://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs.git kernel-6.18.clone3
- Rename shadow_stack_token to shstk_token, since it's a simple rename I've
kept the acks and reviews but I dropped the tested-bys just to be safe.
- Link to v20: https://lore.kernel.org/r/20250902-clone3-shadow-stack-v20-0-4d9fff1c53e7@k…
Changes in v20:
- Comment fixes and clarifications in x86 arch_shstk_validate_clone()
from Rick Edgecombe.
- Spelling fix in documentation.
- Link to v19: https://lore.kernel.org/r/20250819-clone3-shadow-stack-v19-0-bc957075479b@k…
Changes in v19:
- Rebase onto v6.17-rc1.
- Link to v18: https://lore.kernel.org/r/20250702-clone3-shadow-stack-v18-0-7965d2b694db@k…
Changes in v18:
- Rebase onto v6.16-rc3.
- Thanks to pointers from Yuri Khrustalev this version has been tested
on x86 so I have removed the RFT tag.
- Clarify clone3_shadow_stack_valid() comment about the Kconfig check.
- Remove redundant GCSB DSYNCs in arm64 code.
- Fix token validation on x86.
- Link to v17: https://lore.kernel.org/r/20250609-clone3-shadow-stack-v17-0-8840ed97ff6f@k…
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 | 55 +++++-
arch/x86/include/asm/shstk.h | 11 +-
arch/x86/kernel/process.c | 2 +-
arch/x86/kernel/shstk.c | 53 ++++-
include/asm-generic/cacheflush.h | 11 ++
include/linux/sched/task.h | 17 ++
include/uapi/linux/sched.h | 9 +-
kernel/fork.c | 93 +++++++--
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, 620 insertions(+), 81 deletions(-)
---
base-commit: 76cea30ad520238160bf8f5e2f2803fcd7a08d22
change-id: 20231019-clone3-shadow-stack-15d40d2bf536
Best regards,
--
Mark Brown <broonie(a)kernel.org>
sockmap_redir was introduced to comprehensively test the BPF redirection.
This series strives to increase the tested sockmap/sockhash code coverage;
adds support for skipping the actual redirect part, allowing to simply
SK_DROP or SK_PASS the packet.
BPF_MAP_TYPE_SOCKMAP
BPF_MAP_TYPE_SOCKHASH
x
sk_msg-to-egress
sk_msg-to-ingress
sk_skb-to-egress
sk_skb-to-ingress
x
AF_INET, SOCK_STREAM
AF_INET6, SOCK_STREAM
AF_INET, SOCK_DGRAM
AF_INET6, SOCK_DGRAM
AF_UNIX, SOCK_STREAM
AF_UNIX, SOCK_DGRAM
AF_VSOCK, SOCK_STREAM
AF_VSOCK, SOCK_SEQPACKET
x
SK_REDIRECT
SK_DROP
SK_PASS
Patch 5 ("Support no-redirect SK_DROP/SK_PASS") implements the feature.
Patches 3 ("Rename functions") and 4 ("Let test specify skel's
redirect_type") make preparatory changes.
I also took the opportunity to clean up (Patch 1, "Simplify try_recv()")
and improve a bit (Patch 2, "Fix OOB handling").
$ cd tools/testing/selftests/bpf
$ make
$ sudo ./test_progs -t sockmap_redir
...
Summary: 1/720 PASSED, 0 SKIPPED, 0 FAILED
Signed-off-by: Michal Luczaj <mhal(a)rbox.co>
---
Michal Luczaj (5):
selftests/bpf: sockmap_redir: Simplify try_recv()
selftests/bpf: sockmap_redir: Fix OOB handling
selftests/bpf: sockmap_redir: Rename functions
selftests/bpf: sockmap_redir: Let test specify skel's redirect_type
selftests/bpf: sockmap_redir: Support no-redirect SK_DROP/SK_PASS
.../selftests/bpf/prog_tests/sockmap_redir.c | 143 +++++++++++++++------
1 file changed, 105 insertions(+), 38 deletions(-)
---
base-commit: e8a6a9d3e8cc539d281e77b9df2439f223ec8153
change-id: 20250523-redir-test-pass-drop-2f2a5edca6e1
Best regards,
--
Michal Luczaj <mhal(a)rbox.co>