116 Commits
Author SHA1 Message Date
Thomas WeißschuhandBorislav Petkov (AMD) bed0053a63 selftests: vDSO: vdso_test_correctness: Add a test for time()
Extend the test to also cover the time() function.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://patch.msgid.link/20260227-vdso-selftest-cleanups-v2-6-d84830fa8beb@linutronix.de
2026-03-11 15:23:24 +01:00
Thomas WeißschuhandBorislav Petkov (AMD) a8b22a158a selftests: vDSO: vdso_test_correctness: Use facilities from parse_vdso.c
The soname from the vDSO is not a public API. Furthermore it requires
libc to implement dlsym() and friends.

Use the facilities from parse_vdso.c instead which uses the official
vDSO ABI to find it, aligned with the other vDSO selftests.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://patch.msgid.link/20260227-vdso-selftest-cleanups-v2-5-d84830fa8beb@linutronix.de
2026-03-11 15:23:18 +01:00
Thomas WeißschuhandBorislav Petkov (AMD) 38bc16aa47 selftests: vDSO: vdso_test_correctness: Handle different tv_usec types
On SPARC the field tv_usec of 'struct timespec' is not a 'long int', but
only a regular int. In this case the format string is incorrect and will
trigger compiler warnings.

Avoid the warnings by casting to 'long long', similar to how it is done for
the tv_sec and what the other similar selftests are doing.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Tested-by: Andreas Larsson <andreas@gaisler.com>
Reviewed-by: Andreas Larsson <andreas@gaisler.com>
Link: https://patch.msgid.link/20260227-vdso-selftest-cleanups-v2-4-d84830fa8beb@linutronix.de
2026-03-11 15:23:11 +01:00
Thomas WeißschuhandBorislav Petkov (AMD) ad2af7768f selftests: vDSO: vdso_test_correctness: Drop SYS_getcpu fallbacks
These fallbacks are only valid on x86 and unused in the first place.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://patch.msgid.link/20260227-vdso-selftest-cleanups-v2-3-d84830fa8beb@linutronix.de
2026-03-11 15:23:06 +01:00
Thomas WeißschuhandBorislav Petkov (AMD) 50692c25ee selftests: vDSO: vdso_test_gettimeofday: Remove nolibc checks
nolibc now provides these headers, making the check unnecessary.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://patch.msgid.link/20260227-vdso-selftest-cleanups-v2-2-d84830fa8beb@linutronix.de
2026-03-11 15:23:01 +01:00
Thomas WeißschuhandBorislav Petkov (AMD) 5abfa0c4da Revert "selftests: vDSO: parse_vdso: Use UAPI headers instead of libc headers"
This reverts commit c9fbaa8795 ("selftests: vDSO: parse_vdso: Use UAPI
headers instead of libc headers")

The kernel headers were used to make parse_vdso.c compatible with
nolibc.  Unfortunately linux/elf.h is incompatible with glibc's
sys/auxv.h. When using glibc it is therefore not possible build
parse_vdso.c as part of the same compilation unit as its caller
as sys/auxv.h is needed for getauxval().

In the meantime nolibc gained its own elf.h, providing compatibility
with the documented libc interfaces.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://patch.msgid.link/20260227-vdso-selftest-cleanups-v2-1-d84830fa8beb@linutronix.de
2026-03-11 15:22:55 +01:00
Linus Torvalds 6f7e6393d1 Merge tag 'x86_entry_for_7.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 entry code updates from Dave Hansen:
 "This is entirely composed of a set of long overdue VDSO cleanups. They
  makes the VDSO build much more logical and zap quite a bit of old
  cruft.

  It also results in a coveted net-code-removal diffstat"

* tag 'x86_entry_for_7.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/entry/vdso: Add vdso2c to .gitignore
  x86/entry/vdso32: Omit '.cfi_offset eflags' for LLVM < 16
  MAINTAINERS: Adjust vdso file entry in INTEL SGX
  x86/entry/vdso/selftest: Update location of vgetrandom-chacha.S
  x86/entry/vdso: Fix filtering of vdso compiler flags
  x86/entry/vdso: Update the object paths for "make vdso_install"
  x86/entry/vdso32: When using int $0x80, use it directly
  x86/cpufeature: Replace X86_FEATURE_SYSENTER32 with X86_FEATURE_SYSFAST32
  x86/vdso: Abstract out vdso system call internals
  x86/entry/vdso: Include GNU_PROPERTY and GNU_STACK PHDRs
  x86/entry/vdso32: Remove open-coded DWARF in sigreturn.S
  x86/entry/vdso32: Remove SYSCALL_ENTER_KERNEL macro in sigreturn.S
  x86/entry/vdso32: Don't rely on int80_landing_pad for adjusting ip
  x86/entry/vdso: Refactor the vdso build
  x86/entry/vdso: Move vdso2c to arch/x86/tools
  x86/entry/vdso: Rename vdso_image_* to vdso*_image
2026-02-10 19:34:26 -08:00
Linus Torvalds f1c538ca81 Merge tag 'timers-vdso-2026-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull VDSO updates from Thomas Gleixner:

 - Provide the missing 64-bit variant of clock_getres()

   This allows the extension of CONFIG_COMPAT_32BIT_TIME to the vDSO and
   finally the removal of 32-bit time types from the kernel and UAPI.

 - Remove the useless and broken getcpu_cache from the VDSO

   The intention was to provide a trivial way to retrieve the CPU number
   from the VDSO, but as the VDSO data is per process there is no way to
   make it work.

 - Switch get/put_unaligned() from packed struct to memcpy()

   The packed struct violates strict aliasing rules which requires to
   pass -fno-strict-aliasing to the compiler. As this are scalar values
   __builtin_memcpy() turns them into simple loads and stores

 - Use __typeof_unqual__() for __unqual_scalar_typeof()

   The get/put_unaligned() changes triggered a new sparse warning when
   __beNN types are used with get/put_unaligned() as sparse builds add a
   special 'bitwise' attribute to them which prevents sparse to evaluate
   the Generic in __unqual_scalar_typeof().

   Newer sparse versions support __typeof_unqual__() which avoids the
   problem, but requires a recent sparse install. So this adds a sanity
   check to sparse builds, which validates that sparse is available and
   capable of handling it.

 - Force inline __cvdso_clock_getres_common()

   Compilers sometimes un-inline agressively, which results in function
   call overhead and problems with automatic stack variable
   initialization.

   Interestingly enough the force inlining results in smaller code than
   the un-inlined variant produced by GCC when optimizing for size.

* tag 'timers-vdso-2026-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  vdso/gettimeofday: Force inlining of __cvdso_clock_getres_common()
  x86/percpu: Make CONFIG_USE_X86_SEG_SUPPORT work with sparse
  compiler: Use __typeof_unqual__() for __unqual_scalar_typeof()
  powerpc/vdso: Provide clock_getres_time64()
  tools headers: Remove unneeded ignoring of warnings in unaligned.h
  tools headers: Update the linux/unaligned.h copy with the kernel sources
  vdso: Switch get/put_unaligned() from packed struct to memcpy()
  parisc: Inline a type punning version of get_unaligned_le32()
  vdso: Remove struct getcpu_cache
  MIPS: vdso: Provide getres_time64() for 32-bit ABIs
  arm64: vdso32: Provide clock_getres_time64()
  ARM: VDSO: Provide clock_getres_time64()
  ARM: VDSO: Patch out __vdso_clock_getres() if unavailable
  x86/vdso: Provide clock_getres_time64() for x86-32
  selftests: vDSO: vdso_test_abi: Add test for clock_getres_time64()
  selftests: vDSO: vdso_test_abi: Use UAPI system call numbers
  selftests: vDSO: vdso_config: Add configurations for clock_getres_time64()
  vdso: Add prototype for __vdso_clock_getres_time64()
2026-02-10 17:02:23 -08:00
Thomas WeißschuhandHeiko Carstens d045e166d3 selftests: vDSO: getrandom: Fix path to s390 chacha implementation
The s390 vDSO source directory was recently moved,
but this reference was not updated.

Fixes: c0087d807a ("s390/vdso: Rename vdso64 to vdso")
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2026-01-17 15:51:28 +01:00
H. Peter AnvinandDave Hansen db7855c96d x86/entry/vdso/selftest: Update location of vgetrandom-chacha.S
As part of the vdso build restructuring, vgetrandom-chacha.S moved
into the vdso/vdso64 subdirectory. Update the selftest #include to
match.

Closes: https://lore.kernel.org/oe-lkp/202601161608.5cd5af9a-lkp@intel.com
Fixes: 693c819fed ("x86/entry/vdso: Refactor the vdso build")
Reported-by: kernel test robot <oliver.sang@intel.com>
Signed-off-by: H. Peter Anvin (Intel) <hpa@zytor.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://patch.msgid.link/20260116204057.386268-4-hpa@zytor.com
2026-01-16 13:25:44 -08:00
Thomas WeißschuhandThomas Gleixner 7158fc54b2 vdso: Remove struct getcpu_cache
The cache parameter of getcpu() is useless nowadays for various reasons.

  * It is never passed by userspace for either the vDSO or syscalls.
  * It is never used by the kernel.
  * It could not be made to work on the current vDSO architecture.
  * The structure definition is not part of the UAPI headers.
  * vdso_getcpu() is superseded by restartable sequences in any case.

Remove the struct and its header.

As a side-effect this gets rid of an unwanted inclusion of the linux/
header namespace from vDSO code.

[ tglx: Adapt to s390 upstream changes */

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Heiko Carstens <hca@linux.ibm.com> # s390
Link: https://patch.msgid.link/20251230-getcpu_cache-v3-1-fb9c5f880ebe@linutronix.de
2026-01-14 08:56:40 +01:00
Thomas WeißschuhandThomas Gleixner 4e6a231298 selftests: vDSO: vdso_test_abi: Add test for clock_getres_time64()
Some architectures will start to implement this function.
Make sure it works correctly.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/20251223-vdso-compat-time32-v1-4-97ea7a06a543@linutronix.de
2026-01-13 14:42:23 +01:00
Thomas WeißschuhandThomas Gleixner 1dcd1273ad selftests: vDSO: vdso_test_abi: Use UAPI system call numbers
SYS_clock_getres might have been redirected by libc to some other system
call than the actual clock_getres. For testing it is required to use
exactly this system call.

Use the system call number exported by the UAPI headers which is always
correct.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/20251223-vdso-compat-time32-v1-3-97ea7a06a543@linutronix.de
2026-01-13 14:42:23 +01:00
Thomas WeißschuhandThomas Gleixner 609e359ab9 selftests: vDSO: vdso_config: Add configurations for clock_getres_time64()
Some architectures will start to implement this function.
Make sure that tests can be written for it.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/20251223-vdso-compat-time32-v1-2-97ea7a06a543@linutronix.de
2026-01-13 14:42:23 +01:00
Linus Torvalds 509d3f4584 Merge tag 'mm-nonmm-stable-2025-12-06-11-14' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull non-MM updates from Andrew Morton:

 - "panic: sys_info: Refactor and fix a potential issue" (Andy Shevchenko)
   fixes a build issue and does some cleanup in ib/sys_info.c

 - "Implement mul_u64_u64_div_u64_roundup()" (David Laight)
   enhances the 64-bit math code on behalf of a PWM driver and beefs up
   the test module for these library functions

 - "scripts/gdb/symbols: make BPF debug info available to GDB" (Ilya Leoshkevich)
   makes BPF symbol names, sizes, and line numbers available to the GDB
   debugger

 - "Enable hung_task and lockup cases to dump system info on demand" (Feng Tang)
   adds a sysctl which can be used to cause additional info dumping when
   the hung-task and lockup detectors fire

 - "lib/base64: add generic encoder/decoder, migrate users" (Kuan-Wei Chiu)
   adds a general base64 encoder/decoder to lib/ and migrates several
   users away from their private implementations

 - "rbree: inline rb_first() and rb_last()" (Eric Dumazet)
   makes TCP a little faster

 - "liveupdate: Rework KHO for in-kernel users" (Pasha Tatashin)
   reworks the KEXEC Handover interfaces in preparation for Live Update
   Orchestrator (LUO), and possibly for other future clients

 - "kho: simplify state machine and enable dynamic updates" (Pasha Tatashin)
   increases the flexibility of KEXEC Handover. Also preparation for LUO

 - "Live Update Orchestrator" (Pasha Tatashin)
   is a major new feature targeted at cloud environments. Quoting the
   cover letter:

      This series introduces the Live Update Orchestrator, a kernel
      subsystem designed to facilitate live kernel updates using a
      kexec-based reboot. This capability is critical for cloud
      environments, allowing hypervisors to be updated with minimal
      downtime for running virtual machines. LUO achieves this by
      preserving the state of selected resources, such as memory,
      devices and their dependencies, across the kernel transition.

      As a key feature, this series includes support for preserving
      memfd file descriptors, which allows critical in-memory data, such
      as guest RAM or any other large memory region, to be maintained in
      RAM across the kexec reboot.

   Mike Rappaport merits a mention here, for his extensive review and
   testing work.

 - "kexec: reorganize kexec and kdump sysfs" (Sourabh Jain)
   moves the kexec and kdump sysfs entries from /sys/kernel/ to
   /sys/kernel/kexec/ and adds back-compatibility symlinks which can
   hopefully be removed one day

 - "kho: fixes for vmalloc restoration" (Mike Rapoport)
   fixes a BUG which was being hit during KHO restoration of vmalloc()
   regions

* tag 'mm-nonmm-stable-2025-12-06-11-14' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (139 commits)
  calibrate: update header inclusion
  Reinstate "resource: avoid unnecessary lookups in find_next_iomem_res()"
  vmcoreinfo: track and log recoverable hardware errors
  kho: fix restoring of contiguous ranges of order-0 pages
  kho: kho_restore_vmalloc: fix initialization of pages array
  MAINTAINERS: TPM DEVICE DRIVER: update the W-tag
  init: replace simple_strtoul with kstrtoul to improve lpj_setup
  KHO: fix boot failure due to kmemleak access to non-PRESENT pages
  Documentation/ABI: new kexec and kdump sysfs interface
  Documentation/ABI: mark old kexec sysfs deprecated
  kexec: move sysfs entries to /sys/kernel/kexec
  test_kho: always print restore status
  kho: free chunks using free_page() instead of kfree()
  selftests/liveupdate: add kexec test for multiple and empty sessions
  selftests/liveupdate: add simple kexec-based selftest for LUO
  selftests/liveupdate: add userspace API selftests
  docs: add documentation for memfd preservation via LUO
  mm: memfd_luo: allow preserving memfd
  liveupdate: luo_file: add private argument to store runtime state
  mm: shmem: export some functions to internal.h
  ...
2025-12-06 14:01:20 -08:00
Bala-Vignesh-ReddyandAndrew Morton e6fbd1759c selftests: complete kselftest include centralization
This follow-up patch completes centralization of kselftest.h and
ksefltest_harness.h includes in remaining seltests files, replacing all
relative paths with a non-relative paths using shared -I include path in
lib.mk

Tested with gcc-13.3 and clang-18.1, and cross-compiled successfully on
riscv, arm64, x86_64 and powerpc arch.

[reddybalavignesh9979@gmail.com: add selftests include path for kselftest.h]
  Link: https://lkml.kernel.org/r/20251017090201.317521-1-reddybalavignesh9979@gmail.com
Link: https://lkml.kernel.org/r/20251016104409.68985-1-reddybalavignesh9979@gmail.com
Signed-off-by: Bala-Vignesh-Reddy <reddybalavignesh9979@gmail.com>
Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/lkml/20250820143954.33d95635e504e94df01930d0@linux-foundation.org/
Reviewed-by: Wei Yang <richard.weiyang@gmail.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Günther Noack <gnoack@google.com>
Cc: Jakub Kacinski <kuba@kernel.org>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mickael Salaun <mic@digikod.net>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Simon Horman <horms@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-27 14:24:31 -08:00
Heiko Carstens 169ebcbb90 tools: Remove s390 compat support
Remove s390 compat support from everything within tools, since s390 compat
support will be removed from the kernel.

Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Thomas Weißschuh <linux@weissschuh.net> # tools/nolibc selftests/nolibc
Reviewed-by: Thomas Weißschuh <linux@weissschuh.net> # selftests/vDSO
Acked-by: Alexei Starovoitov <ast@kernel.org> # bpf bits
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2025-11-17 11:10:38 +01:00
Thomas WeißschuhandThomas Gleixner e82bf7570d selftests: vDSO: Drop vdso_test_clock_getres
vdso_test_abi provides the exact same functionality, properly uses
kselftest.h and explicitly calls into the vDSO without relying on the libc.

Drop the pointless testcase.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20250812-vdso-tests-fixes-v2-8-90f499dd35f8@linutronix.de
2025-09-09 10:57:39 +02:00
Thomas WeißschuhandThomas Gleixner 7262aa781f selftests: vDSO: vdso_test_abi: Add tests for clock_gettime64()
To be y2038-safe, 32-bit userspace needs to explicitly call the 64-bit safe
time APIs. For this the 32-bit vDSOs contains a clock_gettime() variant
which always uses 64-bit time types.

Also test this vDSO function.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20250812-vdso-tests-fixes-v2-7-90f499dd35f8@linutronix.de
2025-09-09 10:57:39 +02:00
Thomas WeißschuhandThomas Gleixner 7b87dbf9d8 selftests: vDSO: vdso_test_abi: Test CPUTIME clocks
The structure is already there anyways, so test the CPUTIME clocks, too.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20250812-vdso-tests-fixes-v2-6-90f499dd35f8@linutronix.de
2025-09-09 10:57:39 +02:00
Thomas WeißschuhandThomas Gleixner 74b408ff06 selftests: vDSO: vdso_test_abi: Use explicit indices for name array
The array relies on the numeric values of the clock IDs.
When reading the code it is not obvious that the order is correct.

Make the code easier to read by using explicit indices.

While at it make the array static.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20250812-vdso-tests-fixes-v2-5-90f499dd35f8@linutronix.de
2025-09-09 10:57:39 +02:00
Thomas WeißschuhandThomas Gleixner d7516f25a9 selftests: vDSO: vdso_test_abi: Drop clock availability tests
The test uses the kselftest.h framework and declares in its testplan to
always execute 16 testcases. If any of the clockids were not available,
the testplan would not be satisfied anymore and the test would fail.
Apparently that never happened, so the clockids are always available.

Remove the pointless checks.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20250812-vdso-tests-fixes-v2-4-90f499dd35f8@linutronix.de
2025-09-09 10:57:39 +02:00
Thomas WeißschuhandThomas Gleixner 3afe371d32 selftests: vDSO: vdso_test_abi: Use ksft_finished()
The existing logic is just an open-coded ksft_finished().
Replace it with the real thing.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20250812-vdso-tests-fixes-v2-3-90f499dd35f8@linutronix.de
2025-09-09 10:57:39 +02:00
Thomas WeißschuhandThomas Gleixner 4b59a9f762 selftests: vDSO: vdso_test_abi: Correctly skip whole test with missing vDSO
If AT_SYSINFO_EHDR is missing the whole test needs to be skipped.
Currently this results in the following output:

	TAP version 13
	1..16
	# AT_SYSINFO_EHDR is not present!

This output is incorrect, as "1..16" still requires the subtest lines to
be printed, which isn't done however.

Switch to the correct skipping functions, so the output now correctly
indicates that no subtests are being run:

	TAP version 13
	1..0 # SKIP AT_SYSINFO_EHDR is not present!

Fixes: 693f5ca08c ("kselftest: Extend vDSO selftest")
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20250812-vdso-tests-fixes-v2-2-90f499dd35f8@linutronix.de
2025-09-09 10:57:38 +02:00
Thomas WeißschuhandThomas Gleixner 9f15e0f9ef selftests: vDSO: Fix -Wunitialized in powerpc VDSO_CALL() wrapper
The _rval register variable is meant to be an output operand of the asm
statement but is instead used as input operand.
clang 20.1 notices this and triggers -Wuninitialized warnings:

tools/testing/selftests/timers/auxclock.c:154:10: error: variable '_rval' is uninitialized when used here [-Werror,-Wuninitialized]
  154 |                 return VDSO_CALL(self->vdso_clock_gettime64, 2, clockid, ts);
      |                        ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
tools/testing/selftests/timers/../vDSO/vdso_call.h:59:10: note: expanded from macro 'VDSO_CALL'
   59 |                 : "r" (_rval)                                           \
      |                        ^~~~~
tools/testing/selftests/timers/auxclock.c:154:10: note: variable '_rval' is declared here
tools/testing/selftests/timers/../vDSO/vdso_call.h:47:2: note: expanded from macro 'VDSO_CALL'
   47 |         register long _rval asm ("r3");                                 \
      |         ^

It seems the list of input and output operands have been switched around.
However as the argument registers are not always initialized they can not
be marked as pure inputs as that would trigger -Wuninitialized warnings.
Adding _rval as another input and output operand does also not work as it
would collide with the existing _r3 variable.

Instead reuse _r3 for both the argument and the return value.

Fixes: 6eda706a53 ("selftests: vDSO: fix the way vDSO functions are called for powerpc")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Link: https://lore.kernel.org/all/20250812-vdso-tests-fixes-v2-1-90f499dd35f8@linutronix.de
Closes: https://lore.kernel.org/oe-kbuild-all/202506180223.BOOk5jDK-lkp@intel.com/
2025-09-09 10:57:38 +02:00