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2026-06-02vdso/datastore: Mark vdso_k_*_data pointers as __ro_after_initThomas Weißschuh
These pointers are only modified once in vdso_setup_data_pages(), during the init phase. Make them read-only after that. Drop __refdata as that would conflict with __ro_after_init. Modpost does accept the reference from a __ro_after_init symbol to an __init one. Fixes: 05988dba1179 ("vdso/datastore: Allocate data pages dynamically") Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@kernel.org> Link: https://patch.msgid.link/20260513-vdso-ro-after-init-v1-1-4b51f74015a4@linutronix.de
2026-03-26vdso/timens: Move functions to new fileThomas Weißschuh
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 <thomas.weissschuh@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@kernel.org> Link: https://patch.msgid.link/20260326-vdso-timens-decoupling-v2-1-c82693a7775f@linutronix.de
2026-03-11vdso/datastore: Allocate data pages dynamicallyThomas Weißschuh
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
2026-03-11vdso/datastore: Drop inclusion of linux/mmap_lock.hThomas Weißschuh
This header is unnecessary and together with some upcoming changes would introduce compiler warnings. Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@kernel.org> Tested-by: Andreas Larsson <andreas@gaisler.com> Reviewed-by: Andreas Larsson <andreas@gaisler.com> Reviewed-by: Christophe Leroy (CS GROUP) <chleroy@kernel.org> Link: https://lore.kernel.org/lkml/20250916-mm-rcuwait-v1-1-39a3beea6ec3@linutronix.de/ Link: https://patch.msgid.link/20260304-vdso-sparc64-generic-2-v6-2-d8eb3b0e1410@linutronix.de
2026-03-11vdso/datastore: Reduce scope of some variables in vvar_fault()Thomas Weißschuh
These variables are only used inside a single branch. Move their declarations there. Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@kernel.org> Tested-by: Andreas Larsson <andreas@gaisler.com> Reviewed-by: Andreas Larsson <andreas@gaisler.com> Reviewed-by: Christophe Leroy (CS GROUP) <chleroy@kernel.org> Link: https://patch.msgid.link/20260304-vdso-sparc64-generic-2-v6-1-d8eb3b0e1410@linutronix.de
2025-09-04vdso/datastore: Gate time data behind CONFIG_GENERIC_GETTIMEOFDAYThomas Weißschuh
When the generic vDSO does not provide time functions, as for example on riscv32, then the time data store is not necessary. Avoid allocating these time data pages when not used. Fixes: df7fcbefa710 ("vdso: Add generic time data storage") Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250826-vdso-cleanups-v1-1-d9b65750e49f@linutronix.de
2025-04-01mseal sysmap: generic vdso vvar mappingHeiko Carstens
With the introduction of the generic vdso data storage the VM_SEALED_SYSMAP vm flag must be moved from the architecture specific _install_special_mapping() call [1] [2] which maps the vvar mapping to generic code. [1] https://lkml.kernel.org/r/20250305021711.3867874-4-jeffxu@google.com [2] https://lkml.kernel.org/r/20250305021711.3867874-5-jeffxu@google.com Link: https://lkml.kernel.org/r/20250311123326.2686682-2-hca@linux.ibm.com Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Jeff Xu <jeffxu@chromium.org> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-03-08vdso: Rework struct vdso_time_data and introduce struct vdso_clockAnna-Maria Behnsen
To support multiple PTP clocks, the VDSO data structure needs to be reworked. All clock specific data will end up in struct vdso_clock and in struct vdso_time_data there will be an array of VDSO clocks. Now that all preparatory changes are in place: Split the clock related struct members into a separate struct vdso_clock. Make sure all users are aware, that vdso_time_data is no longer initialized as an array and vdso_clock is now the array inside vdso_data. Remove the vdso_clock define, which mapped it to vdso_time_data for the transition. Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de> Signed-off-by: Nam Cao <namcao@linutronix.de> Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250303-vdso-clock-v1-19-c1b5c69a166f@linutronix.de
2025-03-08vdso/namespace: Rename timens_setup_vdso_data() to reflect new vdso_clock structAnna-Maria Behnsen
To support multiple PTP clocks, the VDSO data structure needs to be reworked. All clock specific data will end up in struct vdso_clock and in struct vdso_time_data there will be array of VDSO clocks. At the moment, vdso_clock is simply a define which maps vdso_clock to vdso_time_data. For time namespaces, vdso_time_data needs to be set up. But only the clock related part of the vdso_data thats requires this setup. To reflect the future struct vdso_clock, rename timens_setup_vdso_data() to timns_setup_vdso_clock_data(). No functional change. Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de> Signed-off-by: Nam Cao <namcao@linutronix.de> Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250303-vdso-clock-v1-13-c1b5c69a166f@linutronix.de
2025-02-21vdso: Remove remnants of architecture-specific time storageThomas Weißschuh
All users of the time releated parts of the vDSO are now using the generic storage implementation. Remove the therefore unnecessary compatibility accessor functions and symbols. Co-developed-by: Nam Cao <namcao@linutronix.de> Signed-off-by: Nam Cao <namcao@linutronix.de> Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250204-vdso-store-rng-v3-18-13a4669dfc8c@linutronix.de
2025-02-21vdso: Add generic architecture-specific data storageThomas Weißschuh
Some architectures need to expose architecture-specific data to the vDSO. Enable the generic vDSO storage mechanism to both store and map this data. Some architectures require more than a single page, like LoongArch, so prepare for that usecase, too. Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250204-vdso-store-rng-v3-7-13a4669dfc8c@linutronix.de
2025-02-21vdso: Add generic random data storageThomas Weißschuh
Extend the generic vDSO data storage with a page for the random state data. The random state data is stored in a dedicated page, as the existing storage page is only meant for time-related, time-namespace-aware data. This simplifies to access logic to not need to handle time namespaces anymore and also frees up more space in the time-related page. In case further generic vDSO data store is required it can be added to the random state page. Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250204-vdso-store-rng-v3-6-13a4669dfc8c@linutronix.de
2025-02-21vdso: Add generic time data storageThomas Weißschuh
Historically each architecture defined their own way to store the vDSO data page. Add a generic mechanism to provide storage for that page. Furthermore this generic storage will be extended to also provide uniform storage for *non*-time-related data, like the random state or architecture-specific data. These will have their own pages and data structures, so rename 'vdso_data' into 'vdso_time_data' to make that split clear from the name. Also introduce a new consistent naming scheme for the symbols related to the vDSO, which makes it clear if the symbol is accessible from userspace or kernel space and the type of data behind the symbol. The generic fault handler contains an optimization to prefault the vvar page when the timens page is accessed. This was lifted from s390 and x86. Co-developed-by: Nam Cao <namcao@linutronix.de> Signed-off-by: Nam Cao <namcao@linutronix.de> Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250204-vdso-store-rng-v3-5-13a4669dfc8c@linutronix.de