From 05988dba11791ccbb458254484826b32f17f4ad2 Mon Sep 17 00:00:00 2001 From: Thomas Weißschuh Date: Wed, 4 Mar 2026 08:49:00 +0100 Subject: vdso/datastore: Allocate data pages dynamically MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 Signed-off-by: Thomas Gleixner Reviewed-by: Christophe Leroy (CS GROUP) Link: https://patch.msgid.link/20260304-vdso-sparc64-generic-2-v6-3-d8eb3b0e1410@linutronix.de --- include/linux/vdso_datastore.h | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'include/linux') diff --git a/include/linux/vdso_datastore.h b/include/linux/vdso_datastore.h index a91fa24b06e0..0b530428db71 100644 --- a/include/linux/vdso_datastore.h +++ b/include/linux/vdso_datastore.h @@ -2,9 +2,15 @@ #ifndef _LINUX_VDSO_DATASTORE_H #define _LINUX_VDSO_DATASTORE_H +#ifdef CONFIG_HAVE_GENERIC_VDSO #include extern const struct vm_special_mapping vdso_vvar_mapping; struct vm_area_struct *vdso_install_vvar_mapping(struct mm_struct *mm, unsigned long addr); +void __init vdso_setup_data_pages(void); +#else /* !CONFIG_HAVE_GENERIC_VDSO */ +static inline void vdso_setup_data_pages(void) { } +#endif /* CONFIG_HAVE_GENERIC_VDSO */ + #endif /* _LINUX_VDSO_DATASTORE_H */ -- cgit v1.2.3 From c453b9abb4f422461c1493ef74d63af0961a2d30 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Wed, 4 Mar 2026 08:49:11 +0100 Subject: clocksource: Remove ARCH_CLOCKSOURCE_DATA MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit After sparc64, there are no remaining users of ARCH_CLOCKSOURCE_DATA and it can just be removed. Signed-off-by: Arnd Bergmann Signed-off-by: Thomas Weißschuh Signed-off-by: Thomas Gleixner Tested-by: Andreas Larsson Reviewed-by: Andreas Larsson Acked-by: John Stultz Link: https://patch.msgid.link/20260304-vdso-sparc64-generic-2-v6-14-d8eb3b0e1410@linutronix.de [Thomas: drop sparc64 bits from the patch] --- include/linux/clocksource.h | 6 +----- kernel/time/Kconfig | 4 ---- 2 files changed, 1 insertion(+), 9 deletions(-) (limited to 'include/linux') diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h index 65b7c41471c3..12d853b18832 100644 --- a/include/linux/clocksource.h +++ b/include/linux/clocksource.h @@ -25,8 +25,7 @@ struct clocksource_base; struct clocksource; struct module; -#if defined(CONFIG_ARCH_CLOCKSOURCE_DATA) || \ - defined(CONFIG_GENERIC_GETTIMEOFDAY) +#if defined(CONFIG_GENERIC_GETTIMEOFDAY) #include #endif @@ -106,9 +105,6 @@ struct clocksource { u64 max_idle_ns; u32 maxadj; u32 uncertainty_margin; -#ifdef CONFIG_ARCH_CLOCKSOURCE_DATA - struct arch_clocksource_data archdata; -#endif u64 max_cycles; u64 max_raw_delta; const char *name; diff --git a/kernel/time/Kconfig b/kernel/time/Kconfig index 7c6a52f7836c..fe3311877097 100644 --- a/kernel/time/Kconfig +++ b/kernel/time/Kconfig @@ -9,10 +9,6 @@ config CLOCKSOURCE_WATCHDOG bool -# Architecture has extra clocksource data -config ARCH_CLOCKSOURCE_DATA - bool - # Architecture has extra clocksource init called from registration config ARCH_CLOCKSOURCE_INIT bool -- cgit v1.2.3 From 5dc9cf835aba73c882348aa4f99be83b6e45ad9b Mon Sep 17 00:00:00 2001 From: Thomas Weißschuh Date: Thu, 26 Mar 2026 12:42:30 +0100 Subject: vdso/timens: Move functions to new file MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit As a preparation of the untangling of time namespaces and the vDSO, move the glue functions between those subsystems into a new file. While at it, switch the mutex lock and mmap_read_lock() in the vDSO namespace code to guard(). Signed-off-by: Thomas Weißschuh Signed-off-by: Thomas Gleixner Link: https://patch.msgid.link/20260326-vdso-timens-decoupling-v2-1-c82693a7775f@linutronix.de --- MAINTAINERS | 2 + include/linux/time_namespace.h | 8 --- kernel/time/Makefile | 2 +- kernel/time/namespace.c | 124 ++------------------------------- kernel/time/namespace_internal.h | 13 ++++ kernel/time/namespace_vdso.c | 146 +++++++++++++++++++++++++++++++++++++++ lib/vdso/datastore.c | 25 ------- 7 files changed, 166 insertions(+), 154 deletions(-) create mode 100644 kernel/time/namespace_internal.h create mode 100644 kernel/time/namespace_vdso.c (limited to 'include/linux') diff --git a/MAINTAINERS b/MAINTAINERS index 77fdfcb55f06..6ad74a5196d1 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -10768,6 +10768,7 @@ S: Maintained T: git git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git timers/vdso F: include/asm-generic/vdso/vsyscall.h F: include/vdso/ +F: kernel/time/namespace_vdso.c F: kernel/time/vsyscall.c F: lib/vdso/ F: tools/testing/selftests/vDSO/ @@ -21000,6 +21001,7 @@ F: include/trace/events/timer* F: kernel/time/itimer.c F: kernel/time/posix-* F: kernel/time/namespace.c +F: kernel/time/namespace_vdso.c POWER MANAGEMENT CORE M: "Rafael J. Wysocki" diff --git a/include/linux/time_namespace.h b/include/linux/time_namespace.h index c514d0e5a45c..0421bf1b13d7 100644 --- a/include/linux/time_namespace.h +++ b/include/linux/time_namespace.h @@ -38,8 +38,6 @@ static inline struct time_namespace *to_time_ns(struct ns_common *ns) return container_of(ns, struct time_namespace, ns); } void __init time_ns_init(void); -extern int vdso_join_timens(struct task_struct *task, - struct time_namespace *ns); extern void timens_commit(struct task_struct *tsk, struct time_namespace *ns); static inline struct time_namespace *get_time_ns(struct time_namespace *ns) @@ -117,12 +115,6 @@ static inline void __init time_ns_init(void) { } -static inline int vdso_join_timens(struct task_struct *task, - struct time_namespace *ns) -{ - return 0; -} - static inline void timens_commit(struct task_struct *tsk, struct time_namespace *ns) { diff --git a/kernel/time/Makefile b/kernel/time/Makefile index f7d52d9543cc..662bccb3b7f9 100644 --- a/kernel/time/Makefile +++ b/kernel/time/Makefile @@ -29,6 +29,6 @@ endif 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 +obj-$(CONFIG_TIME_NS) += namespace.o namespace_vdso.o obj-$(CONFIG_TEST_CLOCKSOURCE_WATCHDOG) += clocksource-wdtest.o obj-$(CONFIG_TIME_KUNIT_TEST) += time_test.o diff --git a/kernel/time/namespace.c b/kernel/time/namespace.c index 652744e00eb4..903f55a2dfb2 100644 --- a/kernel/time/namespace.c +++ b/kernel/time/namespace.c @@ -19,7 +19,7 @@ #include #include -#include +#include "namespace_internal.h" ktime_t do_timens_ktime_to_host(clockid_t clockid, ktime_t tim, struct timens_offsets *ns_offsets) @@ -138,117 +138,7 @@ struct time_namespace *copy_time_ns(u64 flags, return clone_time_ns(user_ns, old_ns); } -static struct timens_offset offset_from_ts(struct timespec64 off) -{ - struct timens_offset ret; - - ret.sec = off.tv_sec; - ret.nsec = off.tv_nsec; - - return ret; -} - -/* - * A time namespace VVAR page has the same layout as the VVAR page which - * contains the system wide VDSO data. - * - * For a normal task the VVAR pages are installed in the normal ordering: - * VVAR - * PVCLOCK - * HVCLOCK - * TIMENS <- Not really required - * - * Now for a timens task the pages are installed in the following order: - * TIMENS - * PVCLOCK - * HVCLOCK - * VVAR - * - * The check for vdso_clock->clock_mode is in the unlikely path of - * the seq begin magic. So for the non-timens case most of the time - * 'seq' is even, so the branch is not taken. - * - * If 'seq' is odd, i.e. a concurrent update is in progress, the extra check - * for vdso_clock->clock_mode is a non-issue. The task is spin waiting for the - * update to finish and for 'seq' to become even anyway. - * - * Timens page has vdso_clock->clock_mode set to VDSO_CLOCKMODE_TIMENS which - * enforces the time namespace handling path. - */ -static void timens_setup_vdso_clock_data(struct vdso_clock *vc, - struct time_namespace *ns) -{ - struct timens_offset *offset = vc->offset; - struct timens_offset monotonic = offset_from_ts(ns->offsets.monotonic); - struct timens_offset boottime = offset_from_ts(ns->offsets.boottime); - - vc->seq = 1; - vc->clock_mode = VDSO_CLOCKMODE_TIMENS; - offset[CLOCK_MONOTONIC] = monotonic; - offset[CLOCK_MONOTONIC_RAW] = monotonic; - offset[CLOCK_MONOTONIC_COARSE] = monotonic; - offset[CLOCK_BOOTTIME] = boottime; - offset[CLOCK_BOOTTIME_ALARM] = boottime; -} - -struct page *find_timens_vvar_page(struct vm_area_struct *vma) -{ - if (likely(vma->vm_mm == current->mm)) - return current->nsproxy->time_ns->vvar_page; - - /* - * VM_PFNMAP | VM_IO protect .fault() handler from being called - * through interfaces like /proc/$pid/mem or - * process_vm_{readv,writev}() as long as there's no .access() - * in special_mapping_vmops(). - * For more details check_vma_flags() and __access_remote_vm() - */ - - WARN(1, "vvar_page accessed remotely"); - - return NULL; -} - -/* - * Protects possibly multiple offsets writers racing each other - * and tasks entering the namespace. - */ -static DEFINE_MUTEX(offset_lock); - -static void timens_set_vvar_page(struct task_struct *task, - struct time_namespace *ns) -{ - struct vdso_time_data *vdata; - struct vdso_clock *vc; - unsigned int i; - - if (ns == &init_time_ns) - return; - - /* Fast-path, taken by every task in namespace except the first. */ - if (likely(ns->frozen_offsets)) - return; - - mutex_lock(&offset_lock); - /* Nothing to-do: vvar_page has been already initialized. */ - if (ns->frozen_offsets) - goto out; - - ns->frozen_offsets = true; - vdata = page_address(ns->vvar_page); - vc = vdata->clock_data; - - for (i = 0; i < CS_BASES; i++) - timens_setup_vdso_clock_data(&vc[i], ns); - - if (IS_ENABLED(CONFIG_POSIX_AUX_CLOCKS)) { - for (i = 0; i < ARRAY_SIZE(vdata->aux_clock_data); i++) - timens_setup_vdso_clock_data(&vdata->aux_clock_data[i], ns); - } - -out: - mutex_unlock(&offset_lock); -} +DEFINE_MUTEX(timens_offset_lock); void free_time_ns(struct time_namespace *ns) { @@ -298,12 +188,6 @@ static void timens_put(struct ns_common *ns) put_time_ns(to_time_ns(ns)); } -void timens_commit(struct task_struct *tsk, struct time_namespace *ns) -{ - timens_set_vvar_page(tsk, ns); - vdso_join_timens(tsk, ns); -} - static int timens_install(struct nsset *nsset, struct ns_common *new) { struct nsproxy *nsproxy = nsset->nsproxy; @@ -428,7 +312,7 @@ int proc_timens_set_offset(struct file *file, struct task_struct *p, goto out; } - mutex_lock(&offset_lock); + mutex_lock(&timens_offset_lock); if (time_ns->frozen_offsets) { err = -EACCES; goto out_unlock; @@ -453,7 +337,7 @@ int proc_timens_set_offset(struct file *file, struct task_struct *p, } out_unlock: - mutex_unlock(&offset_lock); + mutex_unlock(&timens_offset_lock); out: put_time_ns(time_ns); diff --git a/kernel/time/namespace_internal.h b/kernel/time/namespace_internal.h new file mode 100644 index 000000000000..e85da11abb4d --- /dev/null +++ b/kernel/time/namespace_internal.h @@ -0,0 +1,13 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _TIME_NAMESPACE_INTERNAL_H +#define _TIME_NAMESPACE_INTERNAL_H + +#include + +/* + * Protects possibly multiple offsets writers racing each other + * and tasks entering the namespace. + */ +extern struct mutex timens_offset_lock; + +#endif /* _TIME_NAMESPACE_INTERNAL_H */ diff --git a/kernel/time/namespace_vdso.c b/kernel/time/namespace_vdso.c new file mode 100644 index 000000000000..0e154f901501 --- /dev/null +++ b/kernel/time/namespace_vdso.c @@ -0,0 +1,146 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Author: Andrei Vagin + * Author: Dmitry Safonov + */ + +#include +#include +#include +#include +#include + +#include +#include + +#include "namespace_internal.h" + +static struct timens_offset offset_from_ts(struct timespec64 off) +{ + struct timens_offset ret; + + ret.sec = off.tv_sec; + ret.nsec = off.tv_nsec; + + return ret; +} + +/* + * A time namespace VVAR page has the same layout as the VVAR page which + * contains the system wide VDSO data. + * + * For a normal task the VVAR pages are installed in the normal ordering: + * VVAR + * PVCLOCK + * HVCLOCK + * TIMENS <- Not really required + * + * Now for a timens task the pages are installed in the following order: + * TIMENS + * PVCLOCK + * HVCLOCK + * VVAR + * + * The check for vdso_clock->clock_mode is in the unlikely path of + * the seq begin magic. So for the non-timens case most of the time + * 'seq' is even, so the branch is not taken. + * + * If 'seq' is odd, i.e. a concurrent update is in progress, the extra check + * for vdso_clock->clock_mode is a non-issue. The task is spin waiting for the + * update to finish and for 'seq' to become even anyway. + * + * Timens page has vdso_clock->clock_mode set to VDSO_CLOCKMODE_TIMENS which + * enforces the time namespace handling path. + */ +static void timens_setup_vdso_clock_data(struct vdso_clock *vc, + struct time_namespace *ns) +{ + struct timens_offset *offset = vc->offset; + struct timens_offset monotonic = offset_from_ts(ns->offsets.monotonic); + struct timens_offset boottime = offset_from_ts(ns->offsets.boottime); + + vc->seq = 1; + vc->clock_mode = VDSO_CLOCKMODE_TIMENS; + offset[CLOCK_MONOTONIC] = monotonic; + offset[CLOCK_MONOTONIC_RAW] = monotonic; + offset[CLOCK_MONOTONIC_COARSE] = monotonic; + offset[CLOCK_BOOTTIME] = boottime; + offset[CLOCK_BOOTTIME_ALARM] = boottime; +} + +struct page *find_timens_vvar_page(struct vm_area_struct *vma) +{ + if (likely(vma->vm_mm == current->mm)) + return current->nsproxy->time_ns->vvar_page; + + /* + * VM_PFNMAP | VM_IO protect .fault() handler from being called + * through interfaces like /proc/$pid/mem or + * process_vm_{readv,writev}() as long as there's no .access() + * in special_mapping_vmops(). + * For more details check_vma_flags() and __access_remote_vm() + */ + + WARN(1, "vvar_page accessed remotely"); + + return NULL; +} + +static void timens_set_vvar_page(struct task_struct *task, + struct time_namespace *ns) +{ + struct vdso_time_data *vdata; + struct vdso_clock *vc; + unsigned int i; + + if (ns == &init_time_ns) + return; + + /* Fast-path, taken by every task in namespace except the first. */ + if (likely(ns->frozen_offsets)) + return; + + guard(mutex)(&timens_offset_lock); + /* Nothing to-do: vvar_page has been already initialized. */ + if (ns->frozen_offsets) + return; + + ns->frozen_offsets = true; + vdata = page_address(ns->vvar_page); + vc = vdata->clock_data; + + for (i = 0; i < CS_BASES; i++) + timens_setup_vdso_clock_data(&vc[i], ns); + + if (IS_ENABLED(CONFIG_POSIX_AUX_CLOCKS)) { + for (i = 0; i < ARRAY_SIZE(vdata->aux_clock_data); i++) + timens_setup_vdso_clock_data(&vdata->aux_clock_data[i], ns); + } +} + +/* + * The vvar page layout depends on whether a task belongs to the root or + * non-root time namespace. Whenever a task changes its namespace, the VVAR + * page tables are cleared and then they will be re-faulted with a + * corresponding layout. + * See also the comment near timens_setup_vdso_clock_data() for details. + */ +static int vdso_join_timens(struct task_struct *task, struct time_namespace *ns) +{ + struct mm_struct *mm = task->mm; + struct vm_area_struct *vma; + VMA_ITERATOR(vmi, mm, 0); + + guard(mmap_read_lock)(mm); + for_each_vma(vmi, vma) { + if (vma_is_special_mapping(vma, &vdso_vvar_mapping)) + zap_vma_pages(vma); + } + return 0; +} + +void timens_commit(struct task_struct *tsk, struct time_namespace *ns) +{ + timens_set_vvar_page(tsk, ns); + vdso_join_timens(tsk, ns); +} diff --git a/lib/vdso/datastore.c b/lib/vdso/datastore.c index faebf5b7cd6e..cf5d784a4a5a 100644 --- a/lib/vdso/datastore.c +++ b/lib/vdso/datastore.c @@ -132,28 +132,3 @@ struct vm_area_struct *vdso_install_vvar_mapping(struct mm_struct *mm, unsigned VM_MIXEDMAP | VM_SEALED_SYSMAP, &vdso_vvar_mapping); } - -#ifdef CONFIG_TIME_NS -/* - * The vvar page layout depends on whether a task belongs to the root or - * non-root time namespace. Whenever a task changes its namespace, the VVAR - * page tables are cleared and then they will be re-faulted with a - * corresponding layout. - * See also the comment near timens_setup_vdso_clock_data() for details. - */ -int vdso_join_timens(struct task_struct *task, struct time_namespace *ns) -{ - struct mm_struct *mm = task->mm; - struct vm_area_struct *vma; - VMA_ITERATOR(vmi, mm, 0); - - mmap_read_lock(mm); - for_each_vma(vmi, vma) { - if (vma_is_special_mapping(vma, &vdso_vvar_mapping)) - zap_vma_pages(vma); - } - mmap_read_unlock(mm); - - return 0; -} -#endif -- cgit v1.2.3 From 1b6c89285d37114d7efe8ab04102a542581cd7da Mon Sep 17 00:00:00 2001 From: Thomas Weißschuh Date: Thu, 26 Mar 2026 12:42:31 +0100 Subject: timens: Remove dependency on the vDSO MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 Signed-off-by: Thomas Gleixner Link: https://patch.msgid.link/20260326-vdso-timens-decoupling-v2-2-c82693a7775f@linutronix.de --- include/linux/time_namespace.h | 28 ++++++++++++++++------------ init/Kconfig | 4 +++- kernel/time/Makefile | 3 ++- kernel/time/namespace.c | 8 ++++---- kernel/time/namespace_internal.h | 15 +++++++++++++++ kernel/time/namespace_vdso.c | 14 ++++++++++++++ 6 files changed, 54 insertions(+), 18 deletions(-) (limited to 'include/linux') diff --git a/include/linux/time_namespace.h b/include/linux/time_namespace.h index 0421bf1b13d7..c1de21a27c34 100644 --- a/include/linux/time_namespace.h +++ b/include/linux/time_namespace.h @@ -25,7 +25,9 @@ struct time_namespace { struct ucounts *ucounts; struct ns_common ns; struct timens_offsets offsets; +#ifdef CONFIG_TIME_NS_VDSO struct page *vvar_page; +#endif /* If set prevents changing offsets after any task joined namespace. */ bool frozen_offsets; } __randomize_layout; @@ -38,7 +40,6 @@ static inline struct time_namespace *to_time_ns(struct ns_common *ns) return container_of(ns, struct time_namespace, ns); } void __init time_ns_init(void); -extern void timens_commit(struct task_struct *tsk, struct time_namespace *ns); static inline struct time_namespace *get_time_ns(struct time_namespace *ns) { @@ -51,7 +52,6 @@ struct time_namespace *copy_time_ns(u64 flags, struct time_namespace *old_ns); void free_time_ns(struct time_namespace *ns); void timens_on_fork(struct nsproxy *nsproxy, struct task_struct *tsk); -struct page *find_timens_vvar_page(struct vm_area_struct *vma); static inline void put_time_ns(struct time_namespace *ns) { @@ -115,11 +115,6 @@ static inline void __init time_ns_init(void) { } -static inline void timens_commit(struct task_struct *tsk, - struct time_namespace *ns) -{ -} - static inline struct time_namespace *get_time_ns(struct time_namespace *ns) { return NULL; @@ -146,11 +141,6 @@ static inline void timens_on_fork(struct nsproxy *nsproxy, return; } -static inline struct page *find_timens_vvar_page(struct vm_area_struct *vma) -{ - return NULL; -} - static inline void timens_add_monotonic(struct timespec64 *ts) { } static inline void timens_add_boottime(struct timespec64 *ts) { } @@ -167,4 +157,18 @@ static inline ktime_t timens_ktime_to_host(clockid_t clockid, ktime_t tim) } #endif +#ifdef CONFIG_TIME_NS_VDSO +extern void timens_commit(struct task_struct *tsk, struct time_namespace *ns); +struct page *find_timens_vvar_page(struct vm_area_struct *vma); +#else /* !CONFIG_TIME_NS_VDSO */ +static inline void timens_commit(struct task_struct *tsk, struct time_namespace *ns) +{ +} + +static inline struct page *find_timens_vvar_page(struct vm_area_struct *vma) +{ + return NULL; +} +#endif /* CONFIG_TIME_NS_VDSO */ + #endif /* _LINUX_TIMENS_H */ diff --git a/init/Kconfig b/init/Kconfig index 444ce811ea67..5e710b03a27a 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -1386,12 +1386,14 @@ config UTS_NS config TIME_NS bool "TIME namespace" - depends on GENERIC_GETTIMEOFDAY default y help In this namespace boottime and monotonic clocks can be set. The time will keep going with the same pace. +config TIME_NS_VDSO + def_bool TIME_NS && GENERIC_GETTIMEOFDAY + config IPC_NS bool "IPC namespace" depends on (SYSVIPC || POSIX_MQUEUE) diff --git a/kernel/time/Makefile b/kernel/time/Makefile index 662bccb3b7f9..eaf290c972f9 100644 --- a/kernel/time/Makefile +++ b/kernel/time/Makefile @@ -29,6 +29,7 @@ endif obj-$(CONFIG_GENERIC_GETTIMEOFDAY) += vsyscall.o obj-$(CONFIG_DEBUG_FS) += timekeeping_debug.o obj-$(CONFIG_TEST_UDELAY) += test_udelay.o -obj-$(CONFIG_TIME_NS) += namespace.o namespace_vdso.o +obj-$(CONFIG_TIME_NS) += namespace.o +obj-$(CONFIG_TIME_NS_VDSO) += namespace_vdso.o obj-$(CONFIG_TEST_CLOCKSOURCE_WATCHDOG) += clocksource-wdtest.o obj-$(CONFIG_TIME_KUNIT_TEST) += time_test.o diff --git a/kernel/time/namespace.c b/kernel/time/namespace.c index 903f55a2dfb2..42302cc3f3fb 100644 --- a/kernel/time/namespace.c +++ b/kernel/time/namespace.c @@ -93,8 +93,8 @@ static struct time_namespace *clone_time_ns(struct user_namespace *user_ns, if (!ns) goto fail_dec; - ns->vvar_page = alloc_page(GFP_KERNEL_ACCOUNT | __GFP_ZERO); - if (!ns->vvar_page) + err = timens_vdso_alloc_vvar_page(ns); + if (err) goto fail_free; err = ns_common_init(ns); @@ -109,7 +109,7 @@ static struct time_namespace *clone_time_ns(struct user_namespace *user_ns, return ns; fail_free_page: - __free_page(ns->vvar_page); + timens_vdso_free_vvar_page(ns); fail_free: kfree(ns); fail_dec: @@ -146,7 +146,7 @@ void free_time_ns(struct time_namespace *ns) dec_time_namespaces(ns->ucounts); put_user_ns(ns->user_ns); ns_common_free(ns); - __free_page(ns->vvar_page); + timens_vdso_free_vvar_page(ns); /* Concurrent nstree traversal depends on a grace period. */ kfree_rcu(ns, ns.ns_rcu); } diff --git a/kernel/time/namespace_internal.h b/kernel/time/namespace_internal.h index e85da11abb4d..b37ba179f43b 100644 --- a/kernel/time/namespace_internal.h +++ b/kernel/time/namespace_internal.h @@ -4,10 +4,25 @@ #include +struct time_namespace; + /* * Protects possibly multiple offsets writers racing each other * and tasks entering the namespace. */ extern struct mutex timens_offset_lock; +#ifdef CONFIG_TIME_NS_VDSO +int timens_vdso_alloc_vvar_page(struct time_namespace *ns); +void timens_vdso_free_vvar_page(struct time_namespace *ns); +#else /* !CONFIG_TIME_NS_VDSO */ +static inline int timens_vdso_alloc_vvar_page(struct time_namespace *ns) +{ + return 0; +} +static inline void timens_vdso_free_vvar_page(struct time_namespace *ns) +{ +} +#endif /* CONFIG_TIME_NS_VDSO */ + #endif /* _TIME_NAMESPACE_INTERNAL_H */ diff --git a/kernel/time/namespace_vdso.c b/kernel/time/namespace_vdso.c index 0e154f901501..88c075cd16a3 100644 --- a/kernel/time/namespace_vdso.c +++ b/kernel/time/namespace_vdso.c @@ -144,3 +144,17 @@ void timens_commit(struct task_struct *tsk, struct time_namespace *ns) timens_set_vvar_page(tsk, ns); vdso_join_timens(tsk, ns); } + +int timens_vdso_alloc_vvar_page(struct time_namespace *ns) +{ + ns->vvar_page = alloc_page(GFP_KERNEL_ACCOUNT | __GFP_ZERO); + if (!ns->vvar_page) + return -ENOMEM; + + return 0; +} + +void timens_vdso_free_vvar_page(struct time_namespace *ns) +{ + __free_page(ns->vvar_page); +} -- cgit v1.2.3 From c2de5a5be4d60af5f928a2dd2b0f73e17358e346 Mon Sep 17 00:00:00 2001 From: Thomas Weißschuh Date: Mon, 30 Mar 2026 09:07:55 +0200 Subject: timens: Add a __free() wrapper for put_time_ns() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The wrapper will be used to simplify cleanups of 'struct time_namespace'. Signed-off-by: Thomas Weißschuh Signed-off-by: Thomas Gleixner Link: https://patch.msgid.link/20260330-timens-cleanup-v1-1-936e91c9dd30@linutronix.de --- include/linux/time_namespace.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'include/linux') diff --git a/include/linux/time_namespace.h b/include/linux/time_namespace.h index c1de21a27c34..58bd9728df58 100644 --- a/include/linux/time_namespace.h +++ b/include/linux/time_namespace.h @@ -8,6 +8,7 @@ #include #include #include +#include struct user_namespace; extern struct user_namespace init_user_ns; @@ -171,4 +172,6 @@ static inline struct page *find_timens_vvar_page(struct vm_area_struct *vma) } #endif /* CONFIG_TIME_NS_VDSO */ +DEFINE_FREE(time_ns, struct time_namespace *, if (_T) put_time_ns(_T)) + #endif /* _LINUX_TIMENS_H */ -- cgit v1.2.3