From: Yicong Yang <yangyicong(a)hisilicon.com>
Armv8.7 introduces single-copy atomic 64-byte loads and stores
instructions and its variants named under FEAT_{LS64, LS64_V,
LS64_ACCDATA}. Add support for Armv8.7 FEAT_{LS64, LS64_V, LS64_ACCDATA}:
- Add identifying and enabling in the cpufeature list
- Expose the support of these features to userspace through HWCAP3
and cpuinfo
- Add related hwcap test
- Handle the trap of unsupported memory (normal/uncacheable) access in a VM
A real scenario for this feature is that the userspace driver can make use of
this to implement direct WQE (workqueue entry) - a mechanism to fill WQE
directly into the hardware.
This patchset also depends on Marc's patchset[1] for enabling related
features in a VM, HCRX trap handling, etc.
[1] https://lore.kernel.org/linux-arm-kernel/20240815125959.2097734-1-maz@kerne…
Tested with updated hwcap test:
On host:
root@localhost:/# dmesg | grep "All CPU(s) started"
[ 1.600263] CPU: All CPU(s) started at EL2
root@localhost:/# ./hwcap
[snip...]
# LS64 present
ok 169 cpuinfo_match_LS64
ok 170 sigill_LS64
ok 171 # SKIP sigbus_LS64
# LS64_V present
ok 172 cpuinfo_match_LS64_V
ok 173 sigill_LS64_V
ok 174 # SKIP sigbus_LS64_V
# LS64_ACCDATA present
ok 175 cpuinfo_match_LS64_ACCDATA
ok 176 sigill_LS64_ACCDATA
ok 177 # SKIP sigbus_LS64_ACCDATA
# Totals: pass:92 fail:0 xfail:0 xpass:0 skip:85 error:0
On guest:
root@localhost:/# dmesg | grep "All CPU(s) started"
[ 1.375272] CPU: All CPU(s) started at EL1
root@localhost:/# ./hwcap
[snip...]
# LS64 present
ok 169 cpuinfo_match_LS64
ok 170 sigill_LS64
ok 171 # SKIP sigbus_LS64
# LS64_V present
ok 172 cpuinfo_match_LS64_V
ok 173 sigill_LS64_V
ok 174 # SKIP sigbus_LS64_V
# LS64_ACCDATA present
ok 175 cpuinfo_match_LS64_ACCDATA
ok 176 sigill_LS64_ACCDATA
ok 177 # SKIP sigbus_LS64_ACCDATA
# Totals: pass:92 fail:0 xfail:0 xpass:0 skip:85 error:0
Yicong Yang (5):
arm64: Provide basic EL2 setup for FEAT_{LS64, LS64_V, LS64_ACCDATA}
usage at EL0/1
arm64: Add support for FEAT_{LS64, LS64_V, LS64_ACCDATA}
kselftest/arm64: Add HWCAP test for FEAT_{LS64, LS64_V, LS64_ACCDATA}
arm64: Add ESR.DFSC definition of unsupported exclusive or atomic
access
KVM: arm64: Handle DABT caused by LS64* instructions on unsupported
memory
Documentation/arch/arm64/booting.rst | 28 +++++
Documentation/arch/arm64/elf_hwcaps.rst | 9 ++
arch/arm64/include/asm/el2_setup.h | 26 ++++-
arch/arm64/include/asm/esr.h | 8 ++
arch/arm64/include/asm/hwcap.h | 3 +
arch/arm64/include/uapi/asm/hwcap.h | 3 +
arch/arm64/kernel/cpufeature.c | 70 +++++++++++-
arch/arm64/kernel/cpuinfo.c | 3 +
arch/arm64/kvm/mmu.c | 14 +++
arch/arm64/tools/cpucaps | 3 +
tools/testing/selftests/arm64/abi/hwcap.c | 127 ++++++++++++++++++++++
11 files changed, 291 insertions(+), 3 deletions(-)
--
2.24.0
This version 5 patch series replace direct error handling methods with ksft
macros, which provide better reporting.Currently, when the tmpfs test runs,
it does not display any output if it passes,and if it fails
(particularly when not run as root),it simply exits without any warning or
message.
This series of patch adds:
1. Add 'ksft_print_header()' and 'ksft_set_plan()'
to structure test outputs more effectively.
2. Error if not run as root.
3. Replace direct error handling with 'ksft_test_result_*',
'ksft_exit_fail_msg' macros for better reporting.
v4->v5:
- Remove unnecessary pass messages.
- Remove unnecessary use of KSFT_SKIP.
- Add appropriate use of ksft_exit_fail_msg.
v4 1/2: https://lore.kernel.org/all/20241105202639.1977356-2-cvam0000@gmail.com/
v4 2/2: https://lore.kernel.org/all/20241105202639.1977356-3-cvam0000@gmail.com/
v3->v4:
- Start a patchset
- Split patch into smaller patches to make it easy to review.
Patch1 Replace 'ksft_test_result_skip' with 'KSFT_SKIP' during root run check.
Patch2 Replace 'ksft_test_result_fail' with 'KSFT_SKIP' where fail does not make sense,
or failure could be due to not unsupported APIs with appropriate warnings.
v3: https://lore.kernel.org/all/20241028185756.111832-1-cvam0000@gmail.com/
v2->v3:
- Remove extra ksft_set_plan()
- Remove function for unshare()
- Fix the comment style
v2: https://lore.kernel.org/all/20241026191621.2860376-1-cvam0000@gmail.com/
v1->v2:
- Make the commit message more clear.
v1: https://lore.kernel.org/all/20241024200228.1075840-1-cvam0000@gmail.com/T/#u
thanks
Shivam
Shivam Chaudhary (2):
selftests: tmpfs: Add Test-fail if not run as root
selftests: tmpfs: Add kselftest support to tmpfs
.../selftests/tmpfs/bug-link-o-tmpfile.c | 60 ++++++++++++-------
1 file changed, 37 insertions(+), 23 deletions(-)
--
2.45.2
If the selftest is not running as root, it should fail and
give an appropriate warning to the user. This patch adds
ksft_exit_fail_msg() if the test is not running as root.
Logs:
Before change:
TAP version 13
1..1
ok 1 # SKIP This test needs root to run!
After change:
TAP version 13
1..1
Bail out! Error : Need to run as root# Planned tests != run tests (1 != 0)
Totals: pass:0 fail:0 xfail:0 xpass:0 skip:0 error:0
Signed-off-by: Shivam Chaudhary <cvam0000(a)gmail.com>
---
tools/testing/selftests/acct/acct_syscall.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/tools/testing/selftests/acct/acct_syscall.c b/tools/testing/selftests/acct/acct_syscall.c
index e44e8fe1f4a3..7c65deef54e3 100644
--- a/tools/testing/selftests/acct/acct_syscall.c
+++ b/tools/testing/selftests/acct/acct_syscall.c
@@ -24,8 +24,7 @@ int main(void)
// Check if test is run a root
if (geteuid()) {
- ksft_test_result_skip("This test needs root to run!\n");
- return 1;
+ ksft_exit_fail_msg("Error : Need to run as root");
}
// Create file to log closed processes
--
2.45.2
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.
Please note that the x86 portions of this code are build tested only, I
don't appear to have a system that can run CET available to me.
[1] https://lore.kernel.org/linux-arm-kernel/20241001-arm64-gcs-v13-0-222b78d87…
Signed-off-by: Mark Brown <broonie(a)kernel.org>
---
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 | 42 ++++
arch/arm64/include/asm/gcs.h | 8 +-
arch/arm64/kernel/process.c | 8 +-
arch/arm64/mm/gcs.c | 62 +++++-
arch/x86/include/asm/shstk.h | 11 +-
arch/x86/kernel/process.c | 2 +-
arch/x86/kernel/shstk.c | 57 +++++-
include/asm-generic/cacheflush.h | 11 ++
include/linux/sched/task.h | 17 ++
include/uapi/linux/sched.h | 10 +-
kernel/fork.c | 96 +++++++--
tools/testing/selftests/clone3/clone3.c | 226 ++++++++++++++++++----
tools/testing/selftests/clone3/clone3_selftests.h | 65 ++++++-
tools/testing/selftests/ksft_shstk.h | 98 ++++++++++
15 files changed, 633 insertions(+), 81 deletions(-)
---
base-commit: 40384c840ea1944d7c5a392e8975ed088ecf0b37
change-id: 20231019-clone3-shadow-stack-15d40d2bf536
Best regards,
--
Mark Brown <broonie(a)kernel.org>
There are a few patches in vIRQ series that rework the fault.c file. So,
we should fix this before that bigger series touches the same code.
And add missing coverage for IOMMU_FAULT_QUEUE_ALLOC in iommufd_fail_nth.
Thanks!
Nicolin
Nicolin Chen (2):
iommufd/fault: Fix out_fput in iommufd_fault_alloc()
iommufd/selftest: Cover IOMMU_FAULT_QUEUE_ALLOC in iommufd_fail_nth
drivers/iommu/iommufd/fault.c | 2 --
tools/testing/selftests/iommu/iommufd_fail_nth.c | 14 ++++++++++++++
2 files changed, 14 insertions(+), 2 deletions(-)
--
2.43.0
Currently, sendmmsg is implemented in udpgso_bench_tx.c,
but it is not called by any test script.
This patch adds a test for sendmmsg in udpgso_bench.sh.
This allows for basic API testing and benchmarking
comparisons with GSO.
---
tools/testing/selftests/net/udpgso_bench.sh | 3 +++
1 file changed, 3 insertions(+)
diff --git a/tools/testing/selftests/net/udpgso_bench.sh b/tools/testing/selftests/net/udpgso_bench.sh
index 640bc43452fa..88fa1d53ba2b 100755
--- a/tools/testing/selftests/net/udpgso_bench.sh
+++ b/tools/testing/selftests/net/udpgso_bench.sh
@@ -92,6 +92,9 @@ run_udp() {
echo "udp"
run_in_netns ${args}
+ echo "udp sendmmsg"
+ run_in_netns ${args} -m
+
echo "udp gso"
run_in_netns ${args} -S 0
--
2.39.3 (Apple Git-146)
As discussed in the v1 [1], with guest_memfd moving from KVM to mm, it
is more practical to have a non-KVM-specific API to populate guest
memory in a generic way. The series proposes using the write syscall
for this purpose instead of a KVM ioctl as in the v1. The approach also
has an advantage that the guest_memfd handle can be sent to another
process that would be responsible for population. I also included a
suggestion from Mike Day for excluding the code from compilation if AMD
SEV is configured.
There is a potential for refactoring of the kvm_gmem_populate to extract
common parts with the write. I did not do that in this series yet to
keep it clear what the write would do and get feedback on whether
write's behaviour is sensible.
Nikita
[1]: https://lore.kernel.org/kvm/20241024095429.54052-1-kalyazin@amazon.com/T/
Nikita Kalyazin (2):
KVM: guest_memfd: add generic population via write
KVM: selftests: update guest_memfd write tests
.../testing/selftests/kvm/guest_memfd_test.c | 85 +++++++++++++++++--
virt/kvm/guest_memfd.c | 79 +++++++++++++++++
2 files changed, 158 insertions(+), 6 deletions(-)
base-commit: 1508bae37044ebffd7c7e09915f041936f338123
--
2.40.1