The syscall definitions can be built just fine for 32-bit systems.
Also the guard does not cover __arch_get_hw_counter() which is always
used together with those system call fallbacks. Also this header is
unused when no vDSO is built anyways.
Drop the ifdeffery. The logic will be simpler to understand. Furthermore
this prepares the complete removal of CONFIG_GENERIC_TIME_VSYSCALL.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/20260519-vdso-generic_time_vsyscal-v1-1-5c2a5905d5f5@linutronix.de
After switching to the real data pages, the sequence counter needs to be
reloaded from there. The code using vdso_read_begin_timens() assumed
this worked by 'continue' jumping to the *beginning* of the do-while
retry loop. However the 'continue' jumps to the *end* of said loop,
evaluating the exit condition. If the data page has a sequence counter
of '1' it will match the one from the time namespace page and prematurely
exit the retry loop. This would result in garbage returned to the caller.
Reload the sequence counter after switching the pages by using an inner
while loop again, which will loop at most once.
The loop generates slightly better code than an explicit reload through
'seq = vdso_read_begin()'.
Fixes: ed78b7b2c5 ("vdso/gettimeofday: Add a helper to read the sequence lock of a time namespace aware clock")
Reported-by: Ricardo Ribalda <ribalda@chromium.org>
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Tested-by: Ricardo Ribalda <ribalda@chromium.org>
Reviewed-by: Christophe Leroy (CS GROUP) <chleroy@kernel.org>
Link: https://patch.msgid.link/20260422-vdso-aux-timens-loop-v1-1-e2dd8c7164cc@linutronix.de
Closes: https://lore.kernel.org/lkml/CANiDSCsOy0P1if-gJZqOM5pTJ0RDcwVfru1B7KFbTOEMqjPKJw@mail.gmail.com/
The recent addition of explicit constructor orders for fixture tests
broke the ordering of those relative to non-fixture tests and the
reverse-constructor-order detection.
Restore the ordering of the test functions relative to each other by
using the same explicit test order for all test registrations and
__constructor_order_first().
Rename the constant, as it is not specific to TEST_F() anymore.
Link: https://lore.kernel.org/r/20260422-kselftests-harness-order-v2-1-93ea980ea3ac@linutronix.de
Fixes: 6be2681514 ("selftests/harness: order TEST_F and XFAIL_ADD constructors")
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Reviewed-by: Kees Cook <kees@kernel.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
AT_SYSINFO_EHDR defines the auxvector index representing the vDSO
entrypoint. Its value or presence does not depend on whether a vDSO
is actually provided by the kernel.
The definition of AT_SYSINFO_EHDR was gated between CONFIG_VSYSCALL to
avoid a default gate VMA to be created. However that default gate VMA
was removed entirely in commit a6c19dfe39
("arm64,ia64,ppc,s390,sh,tile,um,x86,mm: remove default gate area").
Remove the now unnecessary conditional.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Previously, missing time namespace support in the vDSO meant that time
namespaces needed to be disabled globally. This was expressed in a hard
dependency on the generic vDSO library. This also meant that architectures
without any vDSO or only a stub vDSO could not enable time namespaces.
Now that all architectures using a real vDSO are using the generic library,
that dependency is not necessary anymore.
Remove the dependency and let all architectures enable time namespaces.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/20260326-vdso-timens-decoupling-v2-2-c82693a7775f@linutronix.de
Now that the UAPI headers provide the required definitions, use those.
Some symbols have been renamed, adapt to those.
Also adapt the include path for the custom sign-file rule in the
bpf selftests.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Reviewed-by: Petr Pavlu <petr.pavlu@suse.com>
Reviewed-by: Nicolas Schier <nsc@kernel.org>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
This structure definition is used outside the kernel proper.
For example in kmod and the kernel build environment.
To allow reuse, move it to a new UAPI header.
While it is not a true UAPI, it is a common practice to have
non-UAPI interface definitions in the kernel's UAPI headers.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Reviewed-by: Petr Pavlu <petr.pavlu@suse.com>
Reviewed-by: Nicolas Schier <nsc@kernel.org>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
The purpose of the constant it is not entirely clear from its name.
As this constant is going to be exposed in a UAPI header, give it a more
specific name for clarity. As all its users call it 'marker', use that
wording in the constant itself.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Reviewed-by: Petr Pavlu <petr.pavlu@suse.com>
Reviewed-by: Nicolas Schier <nsc@kernel.org>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
This enum originates in generic cryptographic code and has a very
generic name. Nowadays it is only used for module signatures.
As this enum is going to be exposed in a UAPI header, give it a more
specific name for clarity and consistency.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Reviewed-by: Petr Pavlu <petr.pavlu@suse.com>
Reviewed-by: Nicolas Schier <nsc@kernel.org>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
This definition duplicates a definition from an internal kernel header
which is going to be renamed.
To get rid of an instance of the old name, drop the definition.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Reviewed-by: Petr Pavlu <petr.pavlu@suse.com>
Reviewed-by: Nicolas Schier <nsc@kernel.org>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
The 128-bit atomic cmpxchg implementation uses the SC.Q instruction.
Older versions of GNU AS do not support that instruction, erroring out:
ERROR:root:{standard input}: Assembler messages:
{standard input}:4831: Error: no match insn: sc.q $t0,$t1,$r14
{standard input}:6407: Error: no match insn: sc.q $t0,$t1,$r23
{standard input}:10856: Error: no match insn: sc.q $t0,$t1,$r14
make[4]: *** [../scripts/Makefile.build:289: mm/slub.o] Error 1
(Binutils 2.41)
So test support for SC.Q in Kconfig and disable the atomics if the
instruction is not available.
Fixes: f0e4b1b6e2 ("LoongArch: Add 128-bit atomic cmpxchg support")
Closes: https://lore.kernel.org/lkml/20260216082834-edc51c46-7b7a-4295-8ea5-4d9a3ca2224f@linutronix.de/
Reviewed-by: Xi Ruoyao <xry111@xry111.site>
Acked-by: Hengqi Chen <hengqi.chen@gmail.com>
Tested-by: Hengqi Chen <hengqi.chen@gmail.com>
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
The sentinel value added by the wrapper macros __print_symbolic() et al
prevents the callers from adding their own trailing comma. This makes
constructing symbol list dynamically based on kconfig values tedious.
Drop the sentinel elements, so callers can either specify the trailing
comma or not, just like in regular array initializers.
Signed-off-by: Thomas Weißschuh (Schneider Electric) <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/20260311-hrtimer-cleanups-v1-2-095357392669@linutronix.de
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
vdso/datapage.h includes a lot of headers which are not strictly necessary.
Some of those headers include architecture-specific vDSO headers which
prevent the usage of vdso/datapage.h in kernel code on architectures
without an vDSO. This would be useful however to write generic code using
IS_ENABLED(), for example in drivers/char/random.c.
Remove the unnecessary includes.
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-header-cleanups-v2-13-35d60acf7410@linutronix.de
Currently there are three different open-coded variants of a time
namespace aware variant of vdso_read_begin(). They make the code hard to
read and introduce an inconsistency, as only the first copy uses
unlikely().
Split the code into a shared helper function.
Move that next to the definition of the regular vdso_read_begin(), so
that any future changes can be kept in sync easily.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/20260227-vdso-cleanups-v1-2-c848b4bc4850@linutronix.de
Allocating the data pages as part of the kernel image does not work on
SPARC. The MMU will raise a fault when userspace tries to access them.
Allocate the data pages through the page allocator instead.
Unused pages in the vDSO VMA are still allocated to keep the virtual
addresses aligned. Switch the mapping from PFNs to 'struct page' as that is
required for dynamically allocated pages. This also aligns the allocation
of the datapages with the code pages and is a prerequisite for mlockall()
support.
VM_MIXEDMAP is necessary for the call to vmf_insert_page() in the timens
prefault path to work.
The data pages need to be order-0, non-compound pages so that the mapping
to userspace and the different orderings work.
These pages are also used by the timekeeping, random pool and architecture
initialization code. Some of these are running before the page allocator is
available. To keep these subsytems working without changes, introduce
early, statically data storage which will then replaced by the real one as
soon as that is available.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Reviewed-by: Christophe Leroy (CS GROUP) <chleroy@kernel.org>
Link: https://patch.msgid.link/20260304-vdso-sparc64-generic-2-v6-3-d8eb3b0e1410@linutronix.de
The value of __BITS_PER_LONG from architecture-specific logic should
always match the generic one if that is available. It should also match
the actual C type 'long'.
Mismatches can happen for example when building the compat vDSO. Either
during the compilation, see commit 9a6d3ff10f ("arm64: uapi: Provide
correct __BITS_PER_LONG for the compat vDSO"), or when running sparse
when mismatched CHECKFLAGS are inherited from the kernel build.
Add some consistency checks which detect such issues early and clearly.
The kernel-internal BITS_PER_LONG is not checked as it is derived from
CONFIG_64BIT and therefore breaks for the compat vDSO. See the similar,
deactivated check above.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://patch.msgid.link/20260302-vdso-compat-checkflags-v2-5-78e55baa58ba@linutronix.de
This source file undefines '__powerpc64__' to get the 32-bit system call
numbers from asm/unistd.h. However this symbol is also evaluated by
other headers, among them is asm/bitsperlong.h. The undefinition leads
to an inconsistency between __BITS_PER_LONG and the C type 'long'.
An upcoming consistency check will be tripped by this.
Directly include asm/unistd_32.h to get access to the 32-bit system call
numbers instead.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Link: https://patch.msgid.link/20260302-vdso-compat-checkflags-v2-4-78e55baa58ba@linutronix.de
Some non-code files, like linkescripts, are preprocessed with the C
preprocessor and make use of regular kernel headers.
As -m64 is not passed to those preprocessor invocations this leads
to an inconsistency between __BITS_PER_LONG and the C type 'long'.
An upcoming consistency check will be tripped by this.
Make sure -m64 is also defined for those preprocessing steps.
As KBUILD_CPPFLAGS is inherited by both KBUILD_AFLAGS and KBUILD_CFLAGS,
drop -m64 from these variables.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Link: https://patch.msgid.link/20260302-vdso-compat-checkflags-v2-3-78e55baa58ba@linutronix.de
A recent refactoring of the kernel-docs for stop machine changed the
description of the cpus parameter from "NULL = any online cpu"
to "NULL = run on each online CPU".
However the callback is only executed on a single CPU, not all of them.
The old wording was a bit ambiguous and could have been read both ways.
Reword the documentation to be correct again and hopefully also clearer.
Fixes: fc6f89dc70 ("stop_machine: Improve kernel-doc function-header comments")
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
In the past %pK was preferable to %p as it would not leak raw pointer
values into the kernel log.
Since commit ad67b74d24 ("printk: hash addresses printed with %p")
the regular %p has been improved to avoid this issue.
Furthermore, restricted pointers ("%pK") were never meant to be used
through printk(). They can still unintentionally leak raw pointers or
acquire sleeping locks in atomic contexts.
Switch to the regular pointer formatting which is safer and
easier to reason about.
This was previously fixed in this driver in commit 1ba9fbe403
("drm/msm: Don't use %pK through printk") but an additional usage
was reintroduced in commit 39a750ff5f ("drm/msm/dpu: Add DSPP GC
driver to provide GAMMA_LUT DRM property")
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Fixes: 39a750ff5f ("drm/msm/dpu: Add DSPP GC driver to provide GAMMA_LUT DRM property")
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Patchwork: https://patchwork.freedesktop.org/patch/706229/
Link: https://lore.kernel.org/r/20260223-restricted-pointers-msm-v1-1-14c0b451e372@linutronix.de
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
The current logic to split the 64-bit argument into its 32-bit halves is
byte-order specific and a bit clunky. Use a union instead which is
easier to read and works in all cases.
GCC still generates the same machine code.
While at it, rename the arguments of the __memset64() prototype to
actually reflect their semantics.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
After the merge of the alpha and mm trees, this code does not compile,
as a parameter is missing in a call to page_table_check_pte_clear().
The parameter was re-added in commit d7b4b67eb6 ("mm/page_table_check:
reinstate address parameter in [__]page_table_check_pte_clear()").
The alpha-specific code was newly added in commit dd5712f337 ("alpha:
fix user-space corruption during memory compaction").
Fixes: 4cff5c05e0 ("Merge tag 'mm-stable-2026-02-11-19-22' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm")
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Acked-by: Magnus Lindholm <linmag7@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
ARM big-endian has two different binary formats. BE8 and the older BE32.
They are incompatible with each other.
Handle those when evaluating ARCH_CC_CAN_LINK by using the respective
configuration of the kernel itself.
Fixes: 3df8585afd ("ARM: 9469/1: Implement ARCH_HAS_CC_CAN_LINK")
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
The generic CC_CAN_LINK detection does not handle different byte orders
or ABIs. This may lead to userprogs which are not actually runnable on
the target kernel.
Use architecture-specific logic supporting byte orders instead.
Modern 64-bit toolchains default to a n32 libc, which are not
supported by all kernel configurations, as MIPS32_N32 is optional.
On 64-bit, test for a n32 ABI libc first and fall back to o64 and
o32 if necessary.
Link: https://lore.kernel.org/lkml/20260105100507-14db55e3-aa71-48bf-a6ac-33b186bd082f@linutronix.de/
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
The generic CC_CAN_LINK detection does not handle different byte orders.
This may lead to userprogs which are not actually runnable on the target
kernel.
Use architecture-specific logic supporting byte orders instead.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Thomas Weißschuh