Merge tag 'timers-vdso-2025-09-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

torvalds · torvalds · commit 4b81e2eb9e4d · 2025-09-30T16:58:21.000-07:00
Pull VDSO updates from Thomas Gleixner:

 - Further consolidation of the VDSO infrastructure and the common data
   store

 - Simplification of the related Kconfig logic

 - Improve the VDSO selftest suite

* tag 'timers-vdso-2025-09-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  selftests: vDSO: Drop vdso_test_clock_getres
  selftests: vDSO: vdso_test_abi: Add tests for clock_gettime64()
  selftests: vDSO: vdso_test_abi: Test CPUTIME clocks
  selftests: vDSO: vdso_test_abi: Use explicit indices for name array
  selftests: vDSO: vdso_test_abi: Drop clock availability tests
  selftests: vDSO: vdso_test_abi: Use ksft_finished()
  selftests: vDSO: vdso_test_abi: Correctly skip whole test with missing vDSO
  selftests: vDSO: Fix -Wunitialized in powerpc VDSO_CALL() wrapper
  vdso: Add struct __kernel_old_timeval forward declaration to gettime.h
  vdso: Gate VDSO_GETRANDOM behind HAVE_GENERIC_VDSO
  vdso: Drop Kconfig GENERIC_VDSO_TIME_NS
  vdso: Drop Kconfig GENERIC_VDSO_DATA_STORE
  vdso: Drop kconfig GENERIC_COMPAT_VDSO
  vdso: Drop kconfig GENERIC_VDSO_32
  riscv: vdso: Untangle Kconfig logic
  time: Build generic update_vsyscall() only with generic time vDSO
  vdso/gettimeofday: Remove !CONFIG_TIME_NS stubs
  vdso: Move ENABLE_COMPAT_VDSO from core to arm64
  ARM: VDSO: Remove cntvct_ok global variable
  vdso/datastore: Gate time data behind CONFIG_GENERIC_GETTIMEOFDAY
diff --git a/arch/Kconfig b/arch/Kconfig
@@ -1657,7 +1657,7 @@ config HAVE_SPARSE_SYSCALL_NR
 	  related optimizations for a given architecture.
 
 config ARCH_HAS_VDSO_ARCH_DATA
-	depends on GENERIC_VDSO_DATA_STORE
+	depends on HAVE_GENERIC_VDSO
 	bool
 
 config ARCH_HAS_VDSO_TIME_DATA
diff --git a/arch/arm/include/asm/vdso/vsyscall.h b/arch/arm/include/asm/vdso/vsyscall.h
@@ -7,8 +7,6 @@
 #include <vdso/datapage.h>
 #include <asm/cacheflush.h>
 
-extern bool cntvct_ok;
-
 static __always_inline
 void __arch_sync_vdso_time_data(struct vdso_time_data *vdata)
 {
diff --git a/arch/arm/kernel/vdso.c b/arch/arm/kernel/vdso.c
@@ -54,11 +54,9 @@ struct elfinfo {
 	char		*dynstr;	/* ptr to .dynstr section */
 };
 
-/* Cached result of boot-time check for whether the arch timer exists,
- * and if so, whether the virtual counter is useable.
+/* Boot-time check for whether the arch timer exists, and if so,
+ * whether the virtual counter is usable.
  */
-bool cntvct_ok __ro_after_init;
-
 static bool __init cntvct_functional(void)
 {
 	struct device_node *np;
@@ -159,7 +157,7 @@ static void __init patch_vdso(void *ehdr)
 	 * want programs to incur the slight additional overhead of
 	 * dispatching through the VDSO only to fall back to syscalls.
 	 */
-	if (!cntvct_ok) {
+	if (!cntvct_functional()) {
 		vdso_nullpatch_one(&einfo, "__vdso_gettimeofday");
 		vdso_nullpatch_one(&einfo, "__vdso_clock_gettime");
 		vdso_nullpatch_one(&einfo, "__vdso_clock_gettime64");
@@ -197,8 +195,6 @@ static int __init vdso_init(void)
 	vdso_total_pages = VDSO_NR_PAGES; /* for the data/vvar pages */
 	vdso_total_pages += text_pages;
 
-	cntvct_ok = cntvct_functional();
-
 	patch_vdso(vdso_start);
 
 	return 0;
diff --git a/arch/arm/mm/Kconfig b/arch/arm/mm/Kconfig
@@ -926,9 +926,7 @@ config VDSO
 	default y if ARM_ARCH_TIMER
 	select HAVE_GENERIC_VDSO
 	select GENERIC_TIME_VSYSCALL
-	select GENERIC_VDSO_32
 	select GENERIC_GETTIMEOFDAY
-	select GENERIC_VDSO_DATA_STORE
 	help
 	  Place in the process address space an ELF shared object
 	  providing fast implementations of gettimeofday and
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
@@ -166,8 +166,6 @@ config ARM64
 	select GENERIC_SMP_IDLE_THREAD
 	select GENERIC_TIME_VSYSCALL
 	select GENERIC_GETTIMEOFDAY
-	select GENERIC_VDSO_DATA_STORE
-	select GENERIC_VDSO_TIME_NS
 	select HARDIRQS_SW_RESEND
 	select HAS_IOPORT
 	select HAVE_MOVE_PMD
@@ -1750,7 +1748,6 @@ config COMPAT_VDSO
 	bool "Enable vDSO for 32-bit applications"
 	depends on !CPU_BIG_ENDIAN
 	depends on (CC_IS_CLANG && LD_IS_LLD) || "$(CROSS_COMPILE_COMPAT)" != ""
-	select GENERIC_COMPAT_VDSO
 	default y
 	help
 	  Place in the process address space of 32-bit applications an
diff --git a/arch/arm64/include/asm/vdso/compat_barrier.h b/arch/arm64/include/asm/vdso/compat_barrier.h
@@ -7,11 +7,10 @@
 
 #ifndef __ASSEMBLY__
 /*
- * Warning: This code is meant to be used with
- * ENABLE_COMPAT_VDSO only.
+ * Warning: This code is meant to be used from the compat vDSO only.
  */
-#ifndef ENABLE_COMPAT_VDSO
-#error This header is meant to be used with ENABLE_COMPAT_VDSO only
+#ifdef __arch64__
+#error This header is meant to be used with from the compat vDSO only
 #endif
 
 #ifdef dmb
diff --git a/arch/arm64/include/asm/vdso/compat_gettimeofday.h b/arch/arm64/include/asm/vdso/compat_gettimeofday.h
@@ -2,8 +2,8 @@
 /*
  * Copyright (C) 2018 ARM Limited
  */
-#ifndef __ASM_VDSO_GETTIMEOFDAY_H
-#define __ASM_VDSO_GETTIMEOFDAY_H
+#ifndef __ASM_VDSO_COMPAT_GETTIMEOFDAY_H
+#define __ASM_VDSO_COMPAT_GETTIMEOFDAY_H
 
 #ifndef __ASSEMBLY__
 
@@ -163,4 +163,4 @@ static inline bool vdso_clocksource_ok(const struct vdso_clock *vc)
 
 #endif /* !__ASSEMBLY__ */
 
-#endif /* __ASM_VDSO_GETTIMEOFDAY_H */
+#endif /* __ASM_VDSO_COMPAT_GETTIMEOFDAY_H */
diff --git a/arch/arm64/include/asm/vdso/gettimeofday.h b/arch/arm64/include/asm/vdso/gettimeofday.h
@@ -5,6 +5,8 @@
 #ifndef __ASM_VDSO_GETTIMEOFDAY_H
 #define __ASM_VDSO_GETTIMEOFDAY_H
 
+#ifdef __aarch64__
+
 #ifndef __ASSEMBLY__
 
 #include <asm/alternative.h>
@@ -96,4 +98,10 @@ static __always_inline const struct vdso_time_data *__arch_get_vdso_u_time_data(
 
 #endif /* !__ASSEMBLY__ */
 
+#else /* !__aarch64__ */
+
+#include "compat_gettimeofday.h"
+
+#endif /* __aarch64__ */
+
 #endif /* __ASM_VDSO_GETTIMEOFDAY_H */
diff --git a/arch/arm64/kernel/vdso32/Makefile b/arch/arm64/kernel/vdso32/Makefile
@@ -57,7 +57,6 @@ VDSO_CAFLAGS += -DDISABLE_BRANCH_PROFILING
 VDSO_CAFLAGS += -march=armv8-a
 
 VDSO_CFLAGS := $(VDSO_CAFLAGS)
-VDSO_CFLAGS += -DENABLE_COMPAT_VDSO=1
 # KBUILD_CFLAGS from top-level Makefile
 VDSO_CFLAGS += -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs \
                -fno-strict-aliasing -fno-common \
diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig
@@ -110,8 +110,6 @@ config LOONGARCH
 	select GENERIC_SCHED_CLOCK
 	select GENERIC_SMP_IDLE_THREAD
 	select GENERIC_TIME_VSYSCALL
-	select GENERIC_VDSO_DATA_STORE
-	select GENERIC_VDSO_TIME_NS
 	select GPIOLIB
 	select HAS_IOPORT
 	select HAVE_ARCH_AUDITSYSCALL
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
@@ -51,7 +51,6 @@ config MIPS
 	select GENERIC_SMP_IDLE_THREAD
 	select GENERIC_IDLE_POLL_SETUP
 	select GENERIC_TIME_VSYSCALL
-	select GENERIC_VDSO_DATA_STORE
 	select GUP_GET_PXX_LOW_HIGH if CPU_MIPS32 && PHYS_ADDR_T_64BIT
 	select HAS_IOPORT if !NO_IOPORT_MAP || ISA
 	select HAVE_ARCH_COMPILER_H
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
@@ -210,8 +210,6 @@ config PPC
 	select GENERIC_PCI_IOMAP		if PCI
 	select GENERIC_SMP_IDLE_THREAD
 	select GENERIC_TIME_VSYSCALL
-	select GENERIC_VDSO_DATA_STORE
-	select GENERIC_VDSO_TIME_NS
 	select HAS_IOPORT			if PCI
 	select HAVE_ARCH_AUDITSYSCALL
 	select HAVE_ARCH_HUGE_VMALLOC		if HAVE_ARCH_HUGE_VMAP
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
@@ -53,7 +53,7 @@ config RISCV
 	select ARCH_HAS_SYSCALL_WRAPPER
 	select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
 	select ARCH_HAS_UBSAN
-	select ARCH_HAS_VDSO_ARCH_DATA if GENERIC_VDSO_DATA_STORE
+	select ARCH_HAS_VDSO_ARCH_DATA if HAVE_GENERIC_VDSO
 	select ARCH_HAVE_NMI_SAFE_CMPXCHG
 	select ARCH_KEEP_MEMBLOCK if ACPI
 	select ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE	if 64BIT && MMU
@@ -110,7 +110,7 @@ config RISCV
 	select GENERIC_CPU_VULNERABILITIES
 	select GENERIC_EARLY_IOREMAP
 	select GENERIC_ENTRY
-	select GENERIC_GETTIMEOFDAY if HAVE_GENERIC_VDSO
+	select GENERIC_GETTIMEOFDAY if HAVE_GENERIC_VDSO && 64BIT
 	select GENERIC_IDLE_POLL_SETUP
 	select GENERIC_IOREMAP if MMU
 	select GENERIC_IRQ_IPI if SMP
@@ -123,9 +123,7 @@ config RISCV
 	select GENERIC_PCI_IOMAP
 	select GENERIC_SCHED_CLOCK
 	select GENERIC_SMP_IDLE_THREAD
-	select GENERIC_TIME_VSYSCALL if MMU && 64BIT
-	select GENERIC_VDSO_DATA_STORE if MMU
-	select GENERIC_VDSO_TIME_NS if HAVE_GENERIC_VDSO
+	select GENERIC_TIME_VSYSCALL if GENERIC_GETTIMEOFDAY
 	select HARDIRQS_SW_RESEND
 	select HAS_IOPORT if MMU
 	select HAVE_ALIGNED_STRUCT_PAGE
@@ -169,7 +167,7 @@ config RISCV
 	select HAVE_FUNCTION_ARG_ACCESS_API
 	select HAVE_FUNCTION_ERROR_INJECTION
 	select HAVE_GCC_PLUGINS
-	select HAVE_GENERIC_VDSO if MMU && 64BIT
+	select HAVE_GENERIC_VDSO if MMU
 	select HAVE_IRQ_TIME_ACCOUNTING
 	select HAVE_KERNEL_BZIP2 if !XIP_KERNEL && !EFI_ZBOOT
 	select HAVE_KERNEL_GZIP if !XIP_KERNEL && !EFI_ZBOOT
@@ -225,7 +223,7 @@ config RISCV
 	select THREAD_INFO_IN_TASK
 	select TRACE_IRQFLAGS_SUPPORT
 	select UACCESS_MEMCPY if !MMU
-	select VDSO_GETRANDOM if HAVE_GENERIC_VDSO
+	select VDSO_GETRANDOM if HAVE_GENERIC_VDSO && 64BIT
 	select USER_STACKTRACE_SUPPORT
 	select ZONE_DMA32 if 64BIT
 
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
@@ -174,8 +174,6 @@ config S390
 	select GENERIC_GETTIMEOFDAY
 	select GENERIC_SMP_IDLE_THREAD
 	select GENERIC_TIME_VSYSCALL
-	select GENERIC_VDSO_DATA_STORE
-	select GENERIC_VDSO_TIME_NS
 	select GENERIC_IOREMAP if PCI
 	select HAVE_ALIGNED_STRUCT_PAGE
 	select HAVE_ARCH_AUDITSYSCALL
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
@@ -14,7 +14,6 @@ config X86_32
 	select ARCH_WANT_IPC_PARSE_VERSION
 	select CLKSRC_I8253
 	select CLONE_BACKWARDS
-	select GENERIC_VDSO_32
 	select HAVE_DEBUG_STACKOVERFLOW
 	select KMAP_LOCAL
 	select MODULES_USE_ELF_REL
@@ -182,8 +181,6 @@ config X86
 	select GENERIC_SMP_IDLE_THREAD
 	select GENERIC_TIME_VSYSCALL
 	select GENERIC_GETTIMEOFDAY
-	select GENERIC_VDSO_DATA_STORE
-	select GENERIC_VDSO_TIME_NS
 	select GENERIC_VDSO_OVERFLOW_PROTECT
 	select GUP_GET_PXX_LOW_HIGH		if X86_PAE
 	select HARDIRQS_SW_RESEND
diff --git a/include/asm-generic/vdso/vsyscall.h b/include/asm-generic/vdso/vsyscall.h
@@ -4,8 +4,6 @@
 
 #ifndef __ASSEMBLY__
 
-#ifdef CONFIG_GENERIC_VDSO_DATA_STORE
-
 #ifndef __arch_get_vdso_u_time_data
 static __always_inline const struct vdso_time_data *__arch_get_vdso_u_time_data(void)
 {
@@ -20,8 +18,6 @@ static __always_inline const struct vdso_rng_data *__arch_get_vdso_u_rng_data(vo
 }
 #endif
 
-#endif /* CONFIG_GENERIC_VDSO_DATA_STORE */
-
 #ifndef __arch_update_vdso_clock
 static __always_inline void __arch_update_vdso_clock(struct vdso_clock *vc)
 {
diff --git a/include/vdso/datapage.h b/include/vdso/datapage.h
@@ -31,7 +31,7 @@ struct arch_vdso_time_data {};
 
 #if defined(CONFIG_ARCH_HAS_VDSO_ARCH_DATA)
 #include <asm/vdso/arch_data.h>
-#elif defined(CONFIG_GENERIC_VDSO_DATA_STORE)
+#else
 struct vdso_arch_data {
 	/* Needed for the generic code, never actually used at runtime */
 	char __unused;
@@ -164,7 +164,6 @@ struct vdso_rng_data {
  * With the hidden visibility, the compiler simply generates a PC-relative
  * relocation, and this is what we need.
  */
-#ifdef CONFIG_GENERIC_VDSO_DATA_STORE
 extern struct vdso_time_data vdso_u_time_data __attribute__((visibility("hidden")));
 extern struct vdso_rng_data vdso_u_rng_data __attribute__((visibility("hidden")));
 extern struct vdso_arch_data vdso_u_arch_data __attribute__((visibility("hidden")));
@@ -185,8 +184,6 @@ enum vdso_pages {
 	VDSO_NR_PAGES
 };
 
-#endif /* CONFIG_GENERIC_VDSO_DATA_STORE */
-
 /*
  * The generic vDSO implementation requires that gettimeofday.h
  * provides:
@@ -196,11 +193,7 @@ enum vdso_pages {
  * - clock_gettime_fallback(): fallback for clock_gettime.
  * - clock_getres_fallback(): fallback for clock_getres.
  */
-#ifdef ENABLE_COMPAT_VDSO
-#include <asm/vdso/compat_gettimeofday.h>
-#else
 #include <asm/vdso/gettimeofday.h>
-#endif /* ENABLE_COMPAT_VDSO */
 
 #else /* !__ASSEMBLY__ */
 
diff --git a/include/vdso/gettime.h b/include/vdso/gettime.h
@@ -5,6 +5,7 @@
 #include <linux/types.h>
 
 struct __kernel_timespec;
+struct __kernel_old_timeval;
 struct timezone;
 
 #if !defined(CONFIG_64BIT) || defined(BUILD_VDSO32_64)
diff --git a/init/Kconfig b/init/Kconfig
@@ -1363,7 +1363,7 @@ config UTS_NS
 
 config TIME_NS
 	bool "TIME namespace"
-	depends on GENERIC_VDSO_TIME_NS
+	depends on GENERIC_GETTIMEOFDAY
 	default y
 	help
 	  In this namespace boottime and monotonic clocks can be set.
diff --git a/kernel/time/Makefile b/kernel/time/Makefile
@@ -26,7 +26,7 @@ obj-$(CONFIG_LEGACY_TIMER_TICK)			+= tick-legacy.o
 ifeq ($(CONFIG_SMP),y)
  obj-$(CONFIG_NO_HZ_COMMON)			+= timer_migration.o
 endif
-obj-$(CONFIG_HAVE_GENERIC_VDSO)			+= vsyscall.o
+obj-$(CONFIG_GENERIC_GETTIMEOFDAY)		+= vsyscall.o
 obj-$(CONFIG_DEBUG_FS)				+= timekeeping_debug.o
 obj-$(CONFIG_TEST_UDELAY)			+= test_udelay.o
 obj-$(CONFIG_TIME_NS)				+= namespace.o
diff --git a/lib/vdso/Kconfig b/lib/vdso/Kconfig
@@ -12,39 +12,16 @@ config GENERIC_GETTIMEOFDAY
 	  Each architecture that enables this feature has to
 	  provide the fallback implementation.
 
-config GENERIC_VDSO_32
-	bool
-	depends on GENERIC_GETTIMEOFDAY && !64BIT
-	help
-	  This config option helps to avoid possible performance issues
-	  in 32 bit only architectures.
-
-config GENERIC_COMPAT_VDSO
-	bool
-	help
-	  This config option enables the compat VDSO layer.
-
-config GENERIC_VDSO_TIME_NS
-	bool
-	help
-	  Selected by architectures which support time namespaces in the
-	  VDSO
-
 config GENERIC_VDSO_OVERFLOW_PROTECT
 	bool
 	help
 	  Select to add multiplication overflow protection to the VDSO
 	  time getter functions for the price of an extra conditional
 	  in the hotpath.
 
-endif
-
 config VDSO_GETRANDOM
 	bool
 	help
 	  Selected by architectures that support vDSO getrandom().
 
-config GENERIC_VDSO_DATA_STORE
-	bool
-	help
-	  Selected by architectures that use the generic vDSO data store.
+endif
diff --git a/lib/vdso/Makefile b/lib/vdso/Makefile
@@ -1,3 +1,3 @@
 # SPDX-License-Identifier: GPL-2.0-only
 
-obj-$(CONFIG_GENERIC_VDSO_DATA_STORE) += datastore.o
+obj-$(CONFIG_HAVE_GENERIC_VDSO) += datastore.o
diff --git a/lib/vdso/datastore.c b/lib/vdso/datastore.c
@@ -11,14 +11,14 @@
 /*
  * The vDSO data page.
  */
-#ifdef CONFIG_HAVE_GENERIC_VDSO
+#ifdef CONFIG_GENERIC_GETTIMEOFDAY
 static union {
 	struct vdso_time_data	data;
 	u8			page[PAGE_SIZE];
 } vdso_time_data_store __page_aligned_data;
 struct vdso_time_data *vdso_k_time_data = &vdso_time_data_store.data;
 static_assert(sizeof(vdso_time_data_store) == PAGE_SIZE);
-#endif /* CONFIG_HAVE_GENERIC_VDSO */
+#endif /* CONFIG_GENERIC_GETTIMEOFDAY */
 
 #ifdef CONFIG_VDSO_GETRANDOM
 static union {
@@ -46,7 +46,7 @@ static vm_fault_t vvar_fault(const struct vm_special_mapping *sm,
 
 	switch (vmf->pgoff) {
 	case VDSO_TIME_PAGE_OFFSET:
-		if (!IS_ENABLED(CONFIG_HAVE_GENERIC_VDSO))
+		if (!IS_ENABLED(CONFIG_GENERIC_GETTIMEOFDAY))
 			return VM_FAULT_SIGBUS;
 		pfn = __phys_to_pfn(__pa_symbol(vdso_k_time_data));
 		if (timens_page) {
diff --git a/lib/vdso/gettimeofday.c b/lib/vdso/gettimeofday.c
diff --git a/tools/testing/selftests/pidfd/config b/tools/testing/selftests/pidfd/config
diff --git a/tools/testing/selftests/vDSO/.gitignore b/tools/testing/selftests/vDSO/.gitignore
diff --git a/tools/testing/selftests/vDSO/Makefile b/tools/testing/selftests/vDSO/Makefile
diff --git a/tools/testing/selftests/vDSO/vdso_call.h b/tools/testing/selftests/vDSO/vdso_call.h
diff --git a/tools/testing/selftests/vDSO/vdso_test_abi.c b/tools/testing/selftests/vDSO/vdso_test_abi.c
diff --git a/tools/testing/selftests/vDSO/vdso_test_clock_getres.c b/tools/testing/selftests/vDSO/vdso_test_clock_getres.c

Original file line number	Diff line number	Diff line change
`@@ -7,8 +7,6 @@`
`7`	`7`	`#include <vdso/datapage.h>`
`8`	`8`	`#include <asm/cacheflush.h>`
`9`	`9`
`10`		`-extern bool cntvct_ok;`
`11`		`-`
`12`	`10`	`static __always_inline`
`13`	`11`	`void __arch_sync_vdso_time_data(struct vdso_time_data *vdata)`
`14`	`12`	`{`