The 32-bit sparc configuration (--arch sparc) crashes on
the kunit_fault_test. It's known that some architectures don't handle
deliberate segfaults in kernel mode well, so there's a config switch to
disable tests which rely upon it by default.
Use this for the sparc config, making sure the default config for it
passes.
Fixes: 87c9c1631788 ("kunit: tool: add support for QEMU")
Signed-off-by: David Gow <davidgow(a)google.com>
---
Another quick fix to the sparc qemu_config I noticed while testing [1].
---
tools/testing/kunit/qemu_configs/sparc.py | 1 +
1 file changed, 1 insertion(+)
diff --git a/tools/testing/kunit/qemu_configs/sparc.py b/tools/testing/kunit/qemu_configs/sparc.py
index 3131dd299a6e..2019550a1b69 100644
--- a/tools/testing/kunit/qemu_configs/sparc.py
+++ b/tools/testing/kunit/qemu_configs/sparc.py
@@ -2,6 +2,7 @@ from ..qemu_config import QemuArchParams
QEMU_ARCH = QemuArchParams(linux_arch='sparc',
kconfig='''
+CONFIG_KUNIT_FAULT_TEST=n
CONFIG_SPARC32=y
CONFIG_SERIAL_SUNZILOG=y
CONFIG_SERIAL_SUNZILOG_CONSOLE=y
--
2.49.0.604.gff1f9ca942-goog
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 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 | 61 +++++-
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 | 9 +-
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: 8ffd015db85fea3e15a77027fda6c02ced4d2444
change-id: 20231019-clone3-shadow-stack-15d40d2bf536
Best regards,
--
Mark Brown <broonie(a)kernel.org>
This started with a patch that enabled `clippy::ptr_as_ptr`. Benno
Lossin suggested I also look into `clippy::ptr_cast_constness` and I
discovered `clippy::as_ptr_cast_mut`. This series now enables all 3
lints. It also enables `clippy::as_underscore` which ensures other
pointer casts weren't missed. The first commit reduces the need for
pointer casts and is shared with another series[1].
As a later addition, `clippy::cast_lossless` and `clippy::ref_as_ptr`
are also enabled.
Link: https://lore.kernel.org/all/20250307-no-offset-v1-0-0c728f63b69c@gmail.com/ [1]
Signed-off-by: Tamir Duberstein <tamird(a)gmail.com>
---
Changes in v8:
- Use coercion to go ref -> ptr.
- rustfmt.
- Rebase on v6.15-rc1.
- Extract first commit to its own series as it is shared with other
series.
- Link to v7: https://lore.kernel.org/r/20250325-ptr-as-ptr-v7-0-87ab452147b9@gmail.com
Changes in v7:
- Add patch to enable `clippy::ref_as_ptr`.
- Link to v6: https://lore.kernel.org/r/20250324-ptr-as-ptr-v6-0-49d1b7fd4290@gmail.com
Changes in v6:
- Drop strict provenance patch.
- Fix URLs in doc comments.
- Add patch to enable `clippy::cast_lossless`.
- Rebase on rust-next.
- Link to v5: https://lore.kernel.org/r/20250317-ptr-as-ptr-v5-0-5b5f21fa230a@gmail.com
Changes in v5:
- Use `pointer::addr` in OF. (Boqun Feng)
- Add documentation on stubs. (Benno Lossin)
- Mark stubs `#[inline]`.
- Pick up Alice's RB on a shared commit from
https://lore.kernel.org/all/Z9f-3Aj3_FWBZRrm@google.com/.
- Link to v4: https://lore.kernel.org/r/20250315-ptr-as-ptr-v4-0-b2d72c14dc26@gmail.com
Changes in v4:
- Add missing SoB. (Benno Lossin)
- Use `without_provenance_mut` in alloc. (Boqun Feng)
- Limit strict provenance lints to the `kernel` crate to avoid complex
logic in the build system. This can be revisited on MSRV >= 1.84.0.
- Rebase on rust-next.
- Link to v3: https://lore.kernel.org/r/20250314-ptr-as-ptr-v3-0-e7ba61048f4a@gmail.com
Changes in v3:
- Fixed clippy warning in rust/kernel/firmware.rs. (kernel test robot)
Link: https://lore.kernel.org/all/202503120332.YTCpFEvv-lkp@intel.com/
- s/as u64/as bindings::phys_addr_t/g. (Benno Lossin)
- Use strict provenance APIs and enable lints. (Benno Lossin)
- Link to v2: https://lore.kernel.org/r/20250309-ptr-as-ptr-v2-0-25d60ad922b7@gmail.com
Changes in v2:
- Fixed typo in first commit message.
- Added additional patches, converted to series.
- Link to v1: https://lore.kernel.org/r/20250307-ptr-as-ptr-v1-1-582d06514c98@gmail.com
---
Tamir Duberstein (6):
rust: enable `clippy::ptr_as_ptr` lint
rust: enable `clippy::ptr_cast_constness` lint
rust: enable `clippy::as_ptr_cast_mut` lint
rust: enable `clippy::as_underscore` lint
rust: enable `clippy::cast_lossless` lint
rust: enable `clippy::ref_as_ptr` lint
Makefile | 6 ++++++
drivers/gpu/drm/drm_panic_qr.rs | 2 +-
rust/bindings/lib.rs | 3 +++
rust/kernel/alloc/allocator_test.rs | 2 +-
rust/kernel/alloc/kvec.rs | 4 ++--
rust/kernel/block/mq/operations.rs | 2 +-
rust/kernel/block/mq/request.rs | 7 ++++---
rust/kernel/device.rs | 5 +++--
rust/kernel/device_id.rs | 5 +++--
rust/kernel/devres.rs | 19 ++++++++++---------
rust/kernel/dma.rs | 6 +++---
rust/kernel/error.rs | 2 +-
rust/kernel/firmware.rs | 3 ++-
rust/kernel/fs/file.rs | 3 ++-
rust/kernel/io.rs | 18 +++++++++---------
rust/kernel/kunit.rs | 15 +++++++--------
rust/kernel/list/impl_list_item_mod.rs | 2 +-
rust/kernel/miscdevice.rs | 2 +-
rust/kernel/net/phy.rs | 4 ++--
rust/kernel/of.rs | 6 +++---
rust/kernel/pci.rs | 11 +++++++----
rust/kernel/platform.rs | 4 +++-
rust/kernel/print.rs | 11 +++++------
rust/kernel/seq_file.rs | 3 ++-
rust/kernel/str.rs | 16 +++++++++-------
rust/kernel/sync/poll.rs | 2 +-
rust/kernel/time/hrtimer/pin.rs | 2 +-
rust/kernel/time/hrtimer/pin_mut.rs | 2 +-
rust/kernel/uaccess.rs | 10 ++++------
rust/kernel/workqueue.rs | 12 ++++++------
rust/uapi/lib.rs | 3 +++
31 files changed, 107 insertions(+), 85 deletions(-)
---
base-commit: 0af2f6be1b4281385b618cb86ad946eded089ac8
change-id: 20250307-ptr-as-ptr-21b1867fc4d4
prerequisite-change-id: 20250409-container-of-mutness-b153dab4388d:v1
prerequisite-patch-id: 53d5889db599267f87642bb0ae3063c29bc24863
Best regards,
--
Tamir Duberstein <tamird(a)gmail.com>
Hey,
I'm seeing consistent failures for the arch_timer_edge_cases
selftest one ampere-one(x):
==== Test Assertion Failure ====
arm64/arch_timer_edge_cases.c:170: timer_condition == istatus
pid=6277 tid=6277 errno=4 - Interrupted system call
1 0x0000000000403bcf: test_run at arch_timer_edge_cases.c:962
2 0x0000000000401f1f: main at arch_timer_edge_cases.c:1083
3 0x0000ffffa8b2625b: ?? ??:0
4 0x0000ffffa8b2633b: ?? ??:0
5 0x000000000040202f: _start at ??:?
0x1 != 0x0 (timer_condition != istatus)
The (first) test that's failing is from test_timers_in_the_past():
/* Set a timer to counter=0 (in the past) */
test_timer_cval(timer, 0, wm, true, DEF_CNT);
If I understand this correctly then the timer condition is met, an
irq should be raised with the istatus bit from SYS_CNTV_CTL_EL0 set.
What the guest gets for SYS_CNTV_CTL_EL0 is 1 (only the enable bit
set). KVM also reads 1 in timer_save_state() via
read_sysreg_el0(SYS_CNTV_CTL). Is this a HW/FW issue?
These machines have FEAT_ECV (as a test I disabled that in the kernel
but with the same result).
As a hack I set ARCH_TIMER_CTRL_IT_STAT in timer_save_state() when
the timer condition is met and set up traps for the register - this
lets the testcase succeed.
All with the current upstream kernel - but this is not new, I saw
this a couple of months ago but lost access to the machine before
I could debug..
Any hints what to do here?
Sebastian