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2023-02-20Merge tag 'sched-core-2023-02-20' of ↵Linus Torvalds1-0/+4
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler updates from Ingo Molnar: - Improve the scalability of the CFS bandwidth unthrottling logic with large number of CPUs. - Fix & rework various cpuidle routines, simplify interaction with the generic scheduler code. Add __cpuidle methods as noinstr to objtool's noinstr detection and fix boatloads of cpuidle bugs & quirks. - Add new ABI: introduce MEMBARRIER_CMD_GET_REGISTRATIONS, to query previously issued registrations. - Limit scheduler slice duration to the sysctl_sched_latency period, to improve scheduling granularity with a large number of SCHED_IDLE tasks. - Debuggability enhancement on sys_exit(): warn about disabled IRQs, but also enable them to prevent a cascade of followup problems and repeat warnings. - Fix the rescheduling logic in prio_changed_dl(). - Micro-optimize cpufreq and sched-util methods. - Micro-optimize ttwu_runnable() - Micro-optimize the idle-scanning in update_numa_stats(), select_idle_capacity() and steal_cookie_task(). - Update the RSEQ code & self-tests - Constify various scheduler methods - Remove unused methods - Refine __init tags - Documentation updates - Misc other cleanups, fixes * tag 'sched-core-2023-02-20' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (110 commits) sched/rt: pick_next_rt_entity(): check list_entry sched/deadline: Add more reschedule cases to prio_changed_dl() sched/fair: sanitize vruntime of entity being placed sched/fair: Remove capacity inversion detection sched/fair: unlink misfit task from cpu overutilized objtool: mem*() are not uaccess safe cpuidle: Fix poll_idle() noinstr annotation sched/clock: Make local_clock() noinstr sched/clock/x86: Mark sched_clock() noinstr x86/pvclock: Improve atomic update of last_value in pvclock_clocksource_read() x86/atomics: Always inline arch_atomic64*() cpuidle: tracing, preempt: Squash _rcuidle tracing cpuidle: tracing: Warn about !rcu_is_watching() cpuidle: lib/bug: Disable rcu_is_watching() during WARN/BUG cpuidle: drivers: firmware: psci: Dont instrument suspend code KVM: selftests: Fix build of rseq test exit: Detect and fix irq disabled state in oops cpuidle, arm64: Fix the ARM64 cpuidle logic cpuidle: mvebu: Fix duplicate flags assignment sched/fair: Limit sched slice duration ...
2023-02-09mm: replace vma->vm_flags direct modifications with modifier callsSuren Baghdasaryan1-2/+2
Replace direct modifications to vma->vm_flags with calls to modifier functions to be able to track flag changes and to keep vma locking correctness. [akpm@linux-foundation.org: fix drivers/misc/open-dice.c, per Hyeonggon Yoo] Link: https://lkml.kernel.org/r/20230126193752.297968-5-surenb@google.com Signed-off-by: Suren Baghdasaryan <surenb@google.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Mel Gorman <mgorman@techsingularity.net> Acked-by: Mike Rapoport (IBM) <rppt@kernel.org> Acked-by: Sebastian Reichel <sebastian.reichel@collabora.com> Reviewed-by: Liam R. Howlett <Liam.Howlett@Oracle.com> Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arjun Roy <arjunroy@google.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: David Hildenbrand <david@redhat.com> Cc: David Howells <dhowells@redhat.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: David Rientjes <rientjes@google.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Greg Thelen <gthelen@google.com> Cc: Hugh Dickins <hughd@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jann Horn <jannh@google.com> Cc: Joel Fernandes <joelaf@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kent Overstreet <kent.overstreet@linux.dev> Cc: Laurent Dufour <ldufour@linux.ibm.com> Cc: Lorenzo Stoakes <lstoakes@gmail.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Minchan Kim <minchan@google.com> Cc: Paul E. McKenney <paulmck@kernel.org> Cc: Peter Oskolkov <posk@google.com> Cc: Peter Xu <peterx@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Punit Agrawal <punit.agrawal@bytedance.com> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Shakeel Butt <shakeelb@google.com> Cc: Soheil Hassas Yeganeh <soheil@google.com> Cc: Song Liu <songliubraving@fb.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-09mm/mmap: don't use __vma_adjust() in shift_arg_pages()Liam R. Howlett1-2/+2
Introduce shrink_vma() which uses the vma_prepare() and vma_complete() functions to reduce the vma coverage. Convert shift_arg_pages() to use expand_vma() and the new shrink_vma() function. Remove support from __vma_adjust() to reduce a vma size since shift_arg_pages() is the only user that shrinks a VMA in this way. Link: https://lkml.kernel.org/r/20230120162650.984577-46-Liam.Howlett@oracle.com Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-09mm: don't use __vma_adjust() in __split_vma()Liam R. Howlett1-2/+2
Use the abstracted locking and maple tree operations. Since __split_vma() is the only user of the __vma_adjust() function to use the insert argument, drop that argument. Remove the NULL passed through from fs/exec's shift_arg_pages() and mremap() at the same time. Link: https://lkml.kernel.org/r/20230120162650.984577-44-Liam.Howlett@oracle.com Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-09mm: add vma iterator to vma_adjust() argumentsLiam R. Howlett1-7/+4
Change the vma_adjust() function definition to accept the vma iterator and pass it through to __vma_adjust(). Update fs/exec to use the new vma_adjust() function parameters. Update mm/mremap to use the new vma_adjust() function parameters. Revert the __split_vma() calls back from __vma_adjust() to vma_adjust() and pass through the vma iterator. Link: https://lkml.kernel.org/r/20230120162650.984577-37-Liam.Howlett@oracle.com Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-09mm: change mprotect_fixup to vma iteratorLiam R. Howlett1-1/+4
Use the vma iterator so that the iterator can be invalidated or updated to avoid each caller doing so. Link: https://lkml.kernel.org/r/20230120162650.984577-18-Liam.Howlett@oracle.com Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-19fs: port i_{g,u}id_into_vfs{g,u}id() to mnt_idmapChristian Brauner1-4/+4
Convert to struct mnt_idmap. Remove legacy file_mnt_user_ns() and mnt_user_ns(). Last cycle we merged the necessary infrastructure in 256c8aed2b42 ("fs: introduce dedicated idmap type for mounts"). This is just the conversion to struct mnt_idmap. Currently we still pass around the plain namespace that was attached to a mount. This is in general pretty convenient but it makes it easy to conflate namespaces that are relevant on the filesystem with namespaces that are relevent on the mount level. Especially for non-vfs developers without detailed knowledge in this area this can be a potential source for bugs. Once the conversion to struct mnt_idmap is done all helpers down to the really low-level helpers will take a struct mnt_idmap argument instead of two namespace arguments. This way it becomes impossible to conflate the two eliminating the possibility of any bugs. All of the vfs and all filesystems only operate on struct mnt_idmap. Acked-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2023-01-19fs: port privilege checking helpers to mnt_idmapChristian Brauner1-2/+1
Convert to struct mnt_idmap. Last cycle we merged the necessary infrastructure in 256c8aed2b42 ("fs: introduce dedicated idmap type for mounts"). This is just the conversion to struct mnt_idmap. Currently we still pass around the plain namespace that was attached to a mount. This is in general pretty convenient but it makes it easy to conflate namespaces that are relevant on the filesystem with namespaces that are relevent on the mount level. Especially for non-vfs developers without detailed knowledge in this area this can be a potential source for bugs. Once the conversion to struct mnt_idmap is done all helpers down to the really low-level helpers will take a struct mnt_idmap argument instead of two namespace arguments. This way it becomes impossible to conflate the two eliminating the possibility of any bugs. All of the vfs and all filesystems only operate on struct mnt_idmap. Acked-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2023-01-19fs: port ->permission() to pass mnt_idmapChristian Brauner1-2/+3
Convert to struct mnt_idmap. Last cycle we merged the necessary infrastructure in 256c8aed2b42 ("fs: introduce dedicated idmap type for mounts"). This is just the conversion to struct mnt_idmap. Currently we still pass around the plain namespace that was attached to a mount. This is in general pretty convenient but it makes it easy to conflate namespaces that are relevant on the filesystem with namespaces that are relevent on the mount level. Especially for non-vfs developers without detailed knowledge in this area this can be a potential source for bugs. Once the conversion to struct mnt_idmap is done all helpers down to the really low-level helpers will take a struct mnt_idmap argument instead of two namespace arguments. This way it becomes impossible to conflate the two eliminating the possibility of any bugs. All of the vfs and all filesystems only operate on struct mnt_idmap. Acked-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2022-12-27sched: Introduce per-memory-map concurrency IDMathieu Desnoyers1-0/+4
This feature allows the scheduler to expose a per-memory map concurrency ID to user-space. This concurrency ID is within the possible cpus range, and is temporarily (and uniquely) assigned while threads are actively running within a memory map. If a memory map has fewer threads than cores, or is limited to run on few cores concurrently through sched affinity or cgroup cpusets, the concurrency IDs will be values close to 0, thus allowing efficient use of user-space memory for per-cpu data structures. This feature is meant to be exposed by a new rseq thread area field. The primary purpose of this feature is to do the heavy-lifting needed by memory allocators to allow them to use per-cpu data structures efficiently in the following situations: - Single-threaded applications, - Multi-threaded applications on large systems (many cores) with limited cpu affinity mask, - Multi-threaded applications on large systems (many cores) with restricted cgroup cpuset per container. One of the key concern from scheduler maintainers is the overhead associated with additional spin locks or atomic operations in the scheduler fast-path. This is why the following optimization is implemented. On context switch between threads belonging to the same memory map, transfer the mm_cid from prev to next without any atomic ops. This takes care of use-cases involving frequent context switch between threads belonging to the same memory map. Additional optimizations can be done if the spin locks added when context switching between threads belonging to different memory maps end up being a performance bottleneck. Those are left out of this patch though. A performance impact would have to be clearly demonstrated to justify the added complexity. The credit goes to Paul Turner (Google) for the original virtual cpu id idea. This feature is implemented based on the discussions with Paul Turner and Peter Oskolkov (Google), but I took the liberty to implement scheduler fast-path optimizations and my own NUMA-awareness scheme. The rumor has it that Google have been running a rseq vcpu_id extension internally in production for a year. The tcmalloc source code indeed has comments hinting at a vcpu_id prototype extension to the rseq system call [1]. The following benchmarks do not show any significant overhead added to the scheduler context switch by this feature: * perf bench sched messaging (process) Baseline: 86.5±0.3 ms With mm_cid: 86.7±2.6 ms * perf bench sched messaging (threaded) Baseline: 84.3±3.0 ms With mm_cid: 84.7±2.6 ms * hackbench (process) Baseline: 82.9±2.7 ms With mm_cid: 82.9±2.9 ms * hackbench (threaded) Baseline: 85.2±2.6 ms With mm_cid: 84.4±2.9 ms [1] https://github.com/google/tcmalloc/blob/master/tcmalloc/internal/linux_syscall_support.h#L26 Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20221122203932.231377-8-mathieu.desnoyers@efficios.com
2022-12-12Merge tag 'fs.vfsuid.conversion.v6.2' of ↵Linus Torvalds1-8/+8
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/idmapping Pull vfsuid updates from Christian Brauner: "Last cycle we introduced the vfs{g,u}id_t types and associated helpers to gain type safety when dealing with idmapped mounts. That initial work already converted a lot of places over but there were still some left, This converts all remaining places that still make use of non-type safe idmapping helpers to rely on the new type safe vfs{g,u}id based helpers. Afterwards it removes all the old non-type safe helpers" * tag 'fs.vfsuid.conversion.v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/idmapping: fs: remove unused idmapping helpers ovl: port to vfs{g,u}id_t and associated helpers fuse: port to vfs{g,u}id_t and associated helpers ima: use type safe idmapping helpers apparmor: use type safe idmapping helpers caps: use type safe idmapping helpers fs: use type safe idmapping helpers mnt_idmapping: add missing helpers
2022-12-12Merge tag 'execve-v6.2-rc1' of ↵Linus Torvalds1-10/+24
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull execve updates from Kees Cook: "Most are small refactorings and bug fixes, but three things stand out: switching timens (which got reverted before) looks solid now, FOLL_FORCE has been removed (no failures seen yet across several weeks in -next), and some whitespace cleanups (which are long overdue). - Add timens support (when switching mm). This version has survived in -next for the entire cycle (Andrei Vagin) - Various small bug fixes, refactoring, and readability improvements (Bernd Edlinger, Rolf Eike Beer, Bo Liu, Li Zetao Liu Shixin) - Remove FOLL_FORCE for stack setup (Kees Cook) - Whitespace cleanups (Rolf Eike Beer, Kees Cook)" * tag 'execve-v6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: binfmt_misc: fix shift-out-of-bounds in check_special_flags binfmt: Fix error return code in load_elf_fdpic_binary() exec: Remove FOLL_FORCE for stack setup binfmt_elf: replace IS_ERR() with IS_ERR_VALUE() binfmt_elf: simplify error handling in load_elf_phdrs() binfmt_elf: fix documented return value for load_elf_phdrs() exec: simplify initial stack size expansion binfmt: Fix whitespace issues exec: Add comments on check_unsafe_exec() fs counting ELF uapi: add spaces before '{' selftests/timens: add a test for vfork+exit fs/exec: switch timens when a task gets a new mm
2022-11-17exec: Remove FOLL_FORCE for stack setupKees Cook1-1/+1
It does not appear that FOLL_FORCE should be needed for setting up the stack pages. They are allocated using the nascent brpm->vma, which was newly created with VM_STACK_FLAGS, which an arch can override, but they all appear to include VM_WRITE | VM_MAYWRITE. Remove FOLL_FORCE. Cc: Eric Biederman <ebiederm@xmission.com> Cc: David Hildenbrand <david@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: linux-fsdevel@vger.kernel.org Cc: linux-mm@kvack.org Link: https://lore.kernel.org/lkml/202211171439.CDE720EAD@keescook/ Signed-off-by: Kees Cook <keescook@chromium.org>
2022-10-29Merge tag 'mm-hotfixes-stable-2022-10-28' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull misc hotfixes from Andrew Morton: "Eight fix pre-6.0 bugs and the remainder address issues which were introduced in the 6.1-rc merge cycle, or address issues which aren't considered sufficiently serious to warrant a -stable backport" * tag 'mm-hotfixes-stable-2022-10-28' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (23 commits) mm: multi-gen LRU: move lru_gen_add_mm() out of IRQ-off region lib: maple_tree: remove unneeded initialization in mtree_range_walk() mmap: fix remap_file_pages() regression mm/shmem: ensure proper fallback if page faults mm/userfaultfd: replace kmap/kmap_atomic() with kmap_local_page() x86: fortify: kmsan: fix KMSAN fortify builds x86: asm: make sure __put_user_size() evaluates pointer once Kconfig.debug: disable CONFIG_FRAME_WARN for KMSAN by default x86/purgatory: disable KMSAN instrumentation mm: kmsan: export kmsan_copy_page_meta() mm: migrate: fix return value if all subpages of THPs are migrated successfully mm/uffd: fix vma check on userfault for wp mm: prep_compound_tail() clear page->private mm,madvise,hugetlb: fix unexpected data loss with MADV_DONTNEED on hugetlbfs mm/page_isolation: fix clang deadcode warning fs/ext4/super.c: remove unused `deprecated_msg' ipc/msg.c: fix percpu_counter use after free memory tier, sysfs: rename attribute "nodes" to "nodelist" MAINTAINERS: git://github.com -> https://github.com for nilfs2 mm/kmemleak: prevent soft lockup in kmemleak_scan()'s object iteration loops ...
2022-10-28mm: multi-gen LRU: move lru_gen_add_mm() out of IRQ-off regionSebastian Andrzej Siewior1-1/+1
lru_gen_add_mm() has been added within an IRQ-off region in the commit mentioned below. The other invocations of lru_gen_add_mm() are not within an IRQ-off region. The invocation within IRQ-off region is problematic on PREEMPT_RT because the function is using a spin_lock_t which must not be used within IRQ-disabled regions. The other invocations of lru_gen_add_mm() occur while task_struct::alloc_lock is acquired. Move lru_gen_add_mm() after interrupts are enabled and before task_unlock(). Link: https://lkml.kernel.org/r/20221026134830.711887-1-bigeasy@linutronix.de Fixes: bd74fdaea1460 ("mm: multi-gen LRU: support page table walks") Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Acked-by: Yu Zhao <yuzhao@google.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: "Eric W . Biederman" <ebiederm@xmission.com> Cc: Kees Cook <keescook@chromium.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-26fs: use type safe idmapping helpersChristian Brauner1-8/+8
We already ported most parts and filesystems over for v6.0 to the new vfs{g,u}id_t type and associated helpers for v6.0. Convert the remaining places so we can remove all the old helpers. This is a non-functional change. Reviewed-by: Seth Forshee (DigitalOcean) <sforshee@kernel.org> Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2022-10-25exec: simplify initial stack size expansionRolf Eike Beer1-8/+5
I had a hard time trying to understand completely why it is using vm_end in one side of the expression and vm_start in the other one, and using something in the "if" clause that is not an exact copy of what is used below. The whole point is that the stack_size variable that was used in the "if" clause is the difference between vm_start and vm_end, which is not far away but makes this thing harder to read than it must be. Signed-off-by: Rolf Eike Beer <eb@emlix.com> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/2017429.gqNitNVd0C@mobilepool36.emlix.com
2022-10-25binfmt: Fix whitespace issuesKees Cook1-1/+1
Fix the annoying whitespace issues that have been following these files around for years. Cc: linux-fsdevel@vger.kernel.org Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: Christian Brauner (Microsoft) <brauner@kernel.org> Link: https://lore.kernel.org/r/20221018071350.never.230-kees@kernel.org
2022-10-25exec: Add comments on check_unsafe_exec() fs countingKees Cook1-0/+12
Add some comments about what the fs counting is doing in check_unsafe_exec() and how it relates to the call graph. Specifically, we can't force an unshare of the fs because of at least Chrome: https://lore.kernel.org/lkml/86CE201B-5632-4BB7-BCF6-7CB2C2895409@chromium.org/ Cc: Eric Biederman <ebiederm@xmission.com> Cc: linux-fsdevel@vger.kernel.org Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: Christian Brauner (Microsoft) <brauner@kernel.org> Link: https://lore.kernel.org/r/20221018071537.never.662-kees@kernel.org
2022-10-25fs/exec: switch timens when a task gets a new mmAndrei Vagin1-0/+5
Changing a time namespace requires remapping a vvar page, so we don't want to allow doing that if any other tasks can use the same mm. Currently, we install a time namespace when a task is created with a new vm. exec() is another case when a task gets a new mm and so it can switch a time namespace safely, but it isn't handled now. One more issue of the current interface is that clone() with CLONE_VM isn't allowed if the current task has unshared a time namespace (timens_for_children doesn't match the current timens). Both these issues make some inconvenience for users. For example, Alexey and Florian reported that posix_spawn() uses vfork+exec and this pattern doesn't work with time namespaces due to the both described issues. LXC needed to workaround the exec() issue by calling setns. In the commit 133e2d3e81de5 ("fs/exec: allow to unshare a time namespace on vfork+exec"), we tried to fix these issues with minimal impact on UAPI. But it adds extra complexity and some undesirable side effects. Eric suggested fixing the issues properly because here are all the reasons to suppose that there are no users that depend on the old behavior. Cc: Alexey Izbyshev <izbyshev@ispras.ru> Cc: Christian Brauner <brauner@kernel.org> Cc: Dmitry Safonov <0x7f454c46@gmail.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Florian Weimer <fweimer@redhat.com> Cc: Kees Cook <keescook@chromium.org> Suggested-by: "Eric W. Biederman" <ebiederm@xmission.com> Origin-author: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrei Vagin <avagin@gmail.com> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20220921003120.209637-1-avagin@google.com
2022-10-25exec: Copy oldsighand->action under spin-lockBernd Edlinger1-2/+2
unshare_sighand should only access oldsighand->action while holding oldsighand->siglock, to make sure that newsighand->action is in a consistent state. Signed-off-by: Bernd Edlinger <bernd.edlinger@hotmail.de> Cc: stable@vger.kernel.org Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/AM8PR10MB470871DEBD1DED081F9CC391E4389@AM8PR10MB4708.EURPRD10.PROD.OUTLOOK.COM
2022-10-10Merge tag 'mm-stable-2022-10-08' of ↵Linus Torvalds1-6/+8
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - Yu Zhao's Multi-Gen LRU patches are here. They've been under test in linux-next for a couple of months without, to my knowledge, any negative reports (or any positive ones, come to that). - Also the Maple Tree from Liam Howlett. An overlapping range-based tree for vmas. It it apparently slightly more efficient in its own right, but is mainly targeted at enabling work to reduce mmap_lock contention. Liam has identified a number of other tree users in the kernel which could be beneficially onverted to mapletrees. Yu Zhao has identified a hard-to-hit but "easy to fix" lockdep splat at [1]. This has yet to be addressed due to Liam's unfortunately timed vacation. He is now back and we'll get this fixed up. - Dmitry Vyukov introduces KMSAN: the Kernel Memory Sanitizer. It uses clang-generated instrumentation to detect used-unintialized bugs down to the single bit level. KMSAN keeps finding bugs. New ones, as well as the legacy ones. - Yang Shi adds a userspace mechanism (madvise) to induce a collapse of memory into THPs. - Zach O'Keefe has expanded Yang Shi's madvise(MADV_COLLAPSE) to support file/shmem-backed pages. - userfaultfd updates from Axel Rasmussen - zsmalloc cleanups from Alexey Romanov - cleanups from Miaohe Lin: vmscan, hugetlb_cgroup, hugetlb and memory-failure - Huang Ying adds enhancements to NUMA balancing memory tiering mode's page promotion, with a new way of detecting hot pages. - memcg updates from Shakeel Butt: charging optimizations and reduced memory consumption. - memcg cleanups from Kairui Song. - memcg fixes and cleanups from Johannes Weiner. - Vishal Moola provides more folio conversions - Zhang Yi removed ll_rw_block() :( - migration enhancements from Peter Xu - migration error-path bugfixes from Huang Ying - Aneesh Kumar added ability for a device driver to alter the memory tiering promotion paths. For optimizations by PMEM drivers, DRM drivers, etc. - vma merging improvements from Jakub Matěn. - NUMA hinting cleanups from David Hildenbrand. - xu xin added aditional userspace visibility into KSM merging activity. - THP & KSM code consolidation from Qi Zheng. - more folio work from Matthew Wilcox. - KASAN updates from Andrey Konovalov. - DAMON cleanups from Kaixu Xia. - DAMON work from SeongJae Park: fixes, cleanups. - hugetlb sysfs cleanups from Muchun Song. - Mike Kravetz fixes locking issues in hugetlbfs and in hugetlb core. Link: https://lkml.kernel.org/r/CAOUHufZabH85CeUN-MEMgL8gJGzJEWUrkiM58JkTbBhh-jew0Q@mail.gmail.com [1] * tag 'mm-stable-2022-10-08' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (555 commits) hugetlb: allocate vma lock for all sharable vmas hugetlb: take hugetlb vma_lock when clearing vma_lock->vma pointer hugetlb: fix vma lock handling during split vma and range unmapping mglru: mm/vmscan.c: fix imprecise comments mm/mglru: don't sync disk for each aging cycle mm: memcontrol: drop dead CONFIG_MEMCG_SWAP config symbol mm: memcontrol: use do_memsw_account() in a few more places mm: memcontrol: deprecate swapaccounting=0 mode mm: memcontrol: don't allocate cgroup swap arrays when memcg is disabled mm/secretmem: remove reduntant return value mm/hugetlb: add available_huge_pages() func mm: remove unused inline functions from include/linux/mm_inline.h selftests/vm: add selftest for MADV_COLLAPSE of uffd-minor memory selftests/vm: add file/shmem MADV_COLLAPSE selftest for cleared pmd selftests/vm: add thp collapse shmem testing selftests/vm: add thp collapse file and tmpfs testing selftests/vm: modularize thp collapse memory operations selftests/vm: dedup THP helpers mm/khugepaged: add tracepoint to hpage_collapse_scan_file() mm/madvise: add file and shmem support to MADV_COLLAPSE ...
2022-10-09Merge tag 'ucount-rlimits-cleanups-for-v5.19' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull ucounts update from Eric Biederman: "Split rlimit and ucount values and max values After the ucount rlimit code was merged a bunch of small but siginificant bugs were found and fixed. At the time it was realized that part of the problem was that while the ucount rlimits were very similar to the oridinary ucounts (in being nested counts with limits) the semantics were slightly different and the code would be less error prone if there was less sharing. This is the long awaited cleanup that should hopefully keep things more comprehensible and less error prone for whoever needs to touch that code next" * tag 'ucount-rlimits-cleanups-for-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: ucounts: Split rlimit and ucount values and max values
2022-10-06Merge tag 'pull-file_inode' of ↵Linus Torvalds1-2/+1
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull file_inode() updates from Al Vrio: "whack-a-mole: cropped up open-coded file_inode() uses..." * tag 'pull-file_inode' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: orangefs: use ->f_mapping _nfs42_proc_copy(): use ->f_mapping instead of file_inode()->i_mapping dma_buf: no need to bother with file_inode()->i_mapping nfs_finish_open(): don't open-code file_inode() bprm_fill_uid(): don't open-code file_inode() sgx: use ->f_mapping... exfat_iterate(): don't open-code file_inode(file) ibmvmc: don't open-code file_inode()
2022-09-27a.out: Remove the a.out implementationEric W. Biederman1-2/+1
In commit 19e8b701e258 ("a.out: Stop building a.out/osf1 support on alpha and m68k") the last users of a.out were disabled. As nothing has turned up to cause this change to be reverted, let's remove the code implementing a.out support as well. There may be userspace users of the uapi bits left so the uapi headers have been left untouched. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Acked-by: Arnd Bergmann <arnd@arndb.de> # arm defconfigs Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/871qrx3hq3.fsf@email.froward.int.ebiederm.org
2022-09-26exec: use VMA iterator instead of linked listMatthew Wilcox (Oracle)1-3/+6
Remove a use of the vm_next list by doing the initial lookup with the VMA iterator and then using it to find the next entry. Link: https://lkml.kernel.org/r/20220906194824.2110408-42-Liam.Howlett@oracle.com Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com> Tested-by: Yu Zhao <yuzhao@google.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: David Hildenbrand <david@redhat.com> Cc: David Howells <dhowells@redhat.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: SeongJae Park <sj@kernel.org> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-26mm: remove vmacacheLiam R. Howlett1-3/+0
By using the maple tree and the maple tree state, the vmacache is no longer beneficial and is complicating the VMA code. Remove the vmacache to reduce the work in keeping it up to date and code complexity. Link: https://lkml.kernel.org/r/20220906194824.2110408-26-Liam.Howlett@oracle.com Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Tested-by: Yu Zhao <yuzhao@google.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: David Hildenbrand <david@redhat.com> Cc: David Howells <dhowells@redhat.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org> Cc: SeongJae Park <sj@kernel.org> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-26mm: multi-gen LRU: support page table walksYu Zhao1-0/+2
To further exploit spatial locality, the aging prefers to walk page tables to search for young PTEs and promote hot pages. A kill switch will be added in the next patch to disable this behavior. When disabled, the aging relies on the rmap only. NB: this behavior has nothing similar with the page table scanning in the 2.4 kernel [1], which searches page tables for old PTEs, adds cold pages to swapcache and unmaps them. To avoid confusion, the term "iteration" specifically means the traversal of an entire mm_struct list; the term "walk" will be applied to page tables and the rmap, as usual. An mm_struct list is maintained for each memcg, and an mm_struct follows its owner task to the new memcg when this task is migrated. Given an lruvec, the aging iterates lruvec_memcg()->mm_list and calls walk_page_range() with each mm_struct on this list to promote hot pages before it increments max_seq. When multiple page table walkers iterate the same list, each of them gets a unique mm_struct; therefore they can run concurrently. Page table walkers ignore any misplaced pages, e.g., if an mm_struct was migrated, pages it left in the previous memcg will not be promoted when its current memcg is under reclaim. Similarly, page table walkers will not promote pages from nodes other than the one under reclaim. This patch uses the following optimizations when walking page tables: 1. It tracks the usage of mm_struct's between context switches so that page table walkers can skip processes that have been sleeping since the last iteration. 2. It uses generational Bloom filters to record populated branches so that page table walkers can reduce their search space based on the query results, e.g., to skip page tables containing mostly holes or misplaced pages. 3. It takes advantage of the accessed bit in non-leaf PMD entries when CONFIG_ARCH_HAS_NONLEAF_PMD_YOUNG=y. 4. It does not zigzag between a PGD table and the same PMD table spanning multiple VMAs. IOW, it finishes all the VMAs within the range of the same PMD table before it returns to a PGD table. This improves the cache performance for workloads that have large numbers of tiny VMAs [2], especially when CONFIG_PGTABLE_LEVELS=5. Server benchmark results: Single workload: fio (buffered I/O): no change Single workload: memcached (anon): +[8, 10]% Ops/sec KB/sec patch1-7: 1147696.57 44640.29 patch1-8: 1245274.91 48435.66 Configurations: no change Client benchmark results: kswapd profiles: patch1-7 48.16% lzo1x_1_do_compress (real work) 8.20% page_vma_mapped_walk (overhead) 7.06% _raw_spin_unlock_irq 2.92% ptep_clear_flush 2.53% __zram_bvec_write 2.11% do_raw_spin_lock 2.02% memmove 1.93% lru_gen_look_around 1.56% free_unref_page_list 1.40% memset patch1-8 49.44% lzo1x_1_do_compress (real work) 6.19% page_vma_mapped_walk (overhead) 5.97% _raw_spin_unlock_irq 3.13% get_pfn_folio 2.85% ptep_clear_flush 2.42% __zram_bvec_write 2.08% do_raw_spin_lock 1.92% memmove 1.44% alloc_zspage 1.36% memset Configurations: no change Thanks to the following developers for their efforts [3]. kernel test robot <lkp@intel.com> [1] https://lwn.net/Articles/23732/ [2] https://llvm.org/docs/ScudoHardenedAllocator.html [3] https://lore.kernel.org/r/202204160827.ekEARWQo-lkp@intel.com/ Link: https://lkml.kernel.org/r/20220918080010.2920238-9-yuzhao@google.com Signed-off-by: Yu Zhao <yuzhao@google.com> Acked-by: Brian Geffon <bgeffon@google.com> Acked-by: Jan Alexander Steffens (heftig) <heftig@archlinux.org> Acked-by: Oleksandr Natalenko <oleksandr@natalenko.name> Acked-by: Steven Barrett <steven@liquorix.net> Acked-by: Suleiman Souhlal <suleiman@google.com> Tested-by: Daniel Byrne <djbyrne@mtu.edu> Tested-by: Donald Carr <d@chaos-reins.com> Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com> Tested-by: Konstantin Kharlamov <Hi-Angel@yandex.ru> Tested-by: Shuang Zhai <szhai2@cs.rochester.edu> Tested-by: Sofia Trinh <sofia.trinh@edi.works> Tested-by: Vaibhav Jain <vaibhav@linux.ibm.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Cc: Barry Song <baohua@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Hillf Danton <hdanton@sina.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mel Gorman <mgorman@suse.de> Cc: Miaohe Lin <linmiaohe@huawei.com> Cc: Michael Larabel <Michael@MichaelLarabel.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Mike Rapoport <rppt@kernel.org> Cc: Mike Rapoport <rppt@linux.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Qi Zheng <zhengqi.arch@bytedance.com> Cc: Tejun Heo <tj@kernel.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-13Revert "fs/exec: allow to unshare a time namespace on vfork+exec"Andrei Vagin1-7/+0
This reverts commit 133e2d3e81de5d9706cab2dd1d52d231c27382e5. Alexey pointed out a few undesirable side effects of the reverted change. First, it doesn't take into account that CLONE_VFORK can be used with CLONE_THREAD. Second, a child process doesn't enter a target time name-space, if its parent dies before the child calls exec. It happens because the parent clears vfork_done. Eric W. Biederman suggests installing a time namespace as a task gets a new mm. It includes all new processes cloned without CLONE_VM and all tasks that call exec(). This is an user API change, but we think there aren't users that depend on the old behavior. It is too late to make such changes in this release, so let's roll back this patch and introduce the right one in the next release. Cc: Alexey Izbyshev <izbyshev@ispras.ru> Cc: Christian Brauner <brauner@kernel.org> Cc: Dmitry Safonov <0x7f454c46@gmail.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Florian Weimer <fweimer@redhat.com> Cc: Kees Cook <keescook@chromium.org> Signed-off-by: Andrei Vagin <avagin@gmail.com> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20220913102551.1121611-3-avagin@google.com
2022-09-01bprm_fill_uid(): don't open-code file_inode()Al Viro1-2/+1
Reviewed-by: Christian Brauner (Microsoft) <brauner@kernel.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2022-08-19Merge tag 'execve-v6.0-rc2' of ↵Linus Torvalds1-7/+7
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull execve fix from Kees Cook: - Replace remaining kmap() uses with kmap_local_page() (Fabio M. De Francesco) * tag 'execve-v6.0-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: exec: Replace kmap{,_atomic}() with kmap_local_page()
2022-08-16exec: Replace kmap{,_atomic}() with kmap_local_page()Fabio M. De Francesco1-7/+7
The use of kmap() and kmap_atomic() are being deprecated in favor of kmap_local_page(). There are two main problems with kmap(): (1) It comes with an overhead as mapping space is restricted and protected by a global lock for synchronization and (2) it also requires global TLB invalidation when the kmap’s pool wraps and it might block when the mapping space is fully utilized until a slot becomes available. With kmap_local_page() the mappings are per thread, CPU local, can take page faults, and can be called from any context (including interrupts). It is faster than kmap() in kernels with HIGHMEM enabled. Furthermore, the tasks can be preempted and, when they are scheduled to run again, the kernel virtual addresses are restored and are still valid. Since the use of kmap_local_page() in exec.c is safe, it should be preferred everywhere in exec.c. As said, since kmap_local_page() can be also called from atomic context, and since remove_arg_zero() doesn't (and shouldn't ever) rely on an implicit preempt_disable(), this function can also safely replace kmap_atomic(). Therefore, replace kmap() and kmap_atomic() with kmap_local_page() in fs/exec.c. Tested with xfstests on a QEMU/KVM x86_32 VM, 6GB RAM, booting a kernel with HIGHMEM64GB enabled. Cc: Eric W. Biederman <ebiederm@xmission.com> Suggested-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20220803182856.28246-1-fmdefrancesco@gmail.com
2022-08-09posix-cpu-timers: Cleanup CPU timers before freeing them during execThadeu Lima de Souza Cascardo1-0/+3
Commit 55e8c8eb2c7b ("posix-cpu-timers: Store a reference to a pid not a task") started looking up tasks by PID when deleting a CPU timer. When a non-leader thread calls execve, it will switch PIDs with the leader process. Then, as it calls exit_itimers, posix_cpu_timer_del cannot find the task because the timer still points out to the old PID. That means that armed timers won't be disarmed, that is, they won't be removed from the timerqueue_list. exit_itimers will still release their memory, and when that list is later processed, it leads to a use-after-free. Clean up the timers from the de-threaded task before freeing them. This prevents a reported use-after-free. Fixes: 55e8c8eb2c7b ("posix-cpu-timers: Store a reference to a pid not a task") Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20220809170751.164716-1-cascardo@canonical.com
2022-08-02Merge tag 'execve-v5.20-rc1' of ↵Linus Torvalds1-6/+9
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull execve updates from Kees Cook: - Allow unsharing time namespace on vfork+exec (Andrei Vagin) - Replace usage of deprecated kmap APIs (Fabio M. De Francesco) - Fix spelling mistake (Zhang Jiaming) * tag 'execve-v5.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: exec: Call kmap_local_page() in copy_string_kernel() exec: Fix a spelling mistake selftests/timens: add a test for vfork+exit fs/exec: allow to unshare a time namespace on vfork+exec
2022-07-27exec: Call kmap_local_page() in copy_string_kernel()Fabio M. De Francesco1-5/+1
The use of kmap_atomic() is being deprecated in favor of kmap_local_page(). With kmap_local_page(), the mappings are per thread, CPU local and not globally visible. Furthermore, the mappings can be acquired from any context (including interrupts). Therefore, replace kmap_atomic() with kmap_local_page() in copy_string_kernel(). Instead of open-coding local mapping + memcpy(), use memcpy_to_page(). Delete a redundant call to flush_dcache_page(). Tested with xfstests on a QEMU/ KVM x86_32 VM, 6GB RAM, booting a kernel with HIGHMEM64GB enabled. Suggested-by: Ira Weiny <ira.weiny@intel.com> Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20220724212523.13317-1-fmdefrancesco@gmail.com
2022-07-11fix race between exit_itimers() and /proc/pid/timersOleg Nesterov1-1/+1
As Chris explains, the comment above exit_itimers() is not correct, we can race with proc_timers_seq_ops. Change exit_itimers() to clear signal->posix_timers with ->siglock held. Cc: <stable@vger.kernel.org> Reported-by: chris@accessvector.net Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-07-01exec: Fix a spelling mistakeZhang Jiaming1-1/+1
Change 'wont't' to 'won't'. Signed-off-by: Zhang Jiaming <jiaming@nfschina.com> Reviewed-by: Souptick Joarder (HPE) <jrdr.linux@gmail.com> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20220629072932.27506-1-jiaming@nfschina.com
2022-06-15fs/exec: allow to unshare a time namespace on vfork+execAndrei Vagin1-0/+7
Right now, a new process can't be forked in another time namespace if it shares mm with its parent. It is prohibited, because each time namespace has its own vvar page that is mapped into a process address space. When a process calls exec, it gets a new mm and so it could be "legal" to switch time namespace in that case. This was not implemented and now if we want to do this, we need to add another clone flag to not break backward compatibility. We don't have any user requests to switch times on exec except the vfork+exec combination, so there is no reason to add a new clone flag. As for vfork+exec, this should be safe to allow switching timens with the current clone flag. Right now, vfork (CLONE_VFORK | CLONE_VM) fails if a child is forked into another time namespace. With this change, vfork creates a new process in parent's timens, and the following exec does the actual switch to the target time namespace. Suggested-by: Florian Weimer <fweimer@redhat.com> Signed-off-by: Andrei Vagin <avagin@gmail.com> Acked-by: Christian Brauner (Microsoft) <brauner@kernel.org> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20220613060723.197407-1-avagin@gmail.com
2022-06-03Merge tag 'kthread-cleanups-for-v5.19' of ↵Linus Torvalds1-3/+5
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull kthread updates from Eric Biederman: "This updates init and user mode helper tasks to be ordinary user mode tasks. Commit 40966e316f86 ("kthread: Ensure struct kthread is present for all kthreads") caused init and the user m