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2023-08-28Merge tag 'v6.6-vfs.misc' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull misc vfs updates from Christian Brauner: "This contains the usual miscellaneous features, cleanups, and fixes for vfs and individual filesystems. Features: - Block mode changes on symlinks and rectify our broken semantics - Report file modifications via fsnotify() for splice - Allow specifying an explicit timeout for the "rootwait" kernel command line option. This allows to timeout and reboot instead of always waiting indefinitely for the root device to show up - Use synchronous fput for the close system call Cleanups: - Get rid of open-coded lockdep workarounds for async io submitters and replace it all with a single consolidated helper - Simplify epoll allocation helper - Convert simple_write_begin and simple_write_end to use a folio - Convert page_cache_pipe_buf_confirm() to use a folio - Simplify __range_close to avoid pointless locking - Disable per-cpu buffer head cache for isolated cpus - Port ecryptfs to kmap_local_page() api - Remove redundant initialization of pointer buf in pipe code - Unexport the d_genocide() function which is only used within core vfs - Replace printk(KERN_ERR) and WARN_ON() with WARN() Fixes: - Fix various kernel-doc issues - Fix refcount underflow for eventfds when used as EFD_SEMAPHORE - Fix a mainly theoretical issue in devpts - Check the return value of __getblk() in reiserfs - Fix a racy assert in i_readcount_dec - Fix integer conversion issues in various functions - Fix LSM security context handling during automounts that prevented NFS superblock sharing" * tag 'v6.6-vfs.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (39 commits) cachefiles: use kiocb_{start,end}_write() helpers ovl: use kiocb_{start,end}_write() helpers aio: use kiocb_{start,end}_write() helpers io_uring: use kiocb_{start,end}_write() helpers fs: create kiocb_{start,end}_write() helpers fs: add kerneldoc to file_{start,end}_write() helpers io_uring: rename kiocb_end_write() local helper splice: Convert page_cache_pipe_buf_confirm() to use a folio libfs: Convert simple_write_begin and simple_write_end to use a folio fs/dcache: Replace printk and WARN_ON by WARN fs/pipe: remove redundant initialization of pointer buf fs: Fix kernel-doc warnings devpts: Fix kernel-doc warnings doc: idmappings: fix an error and rephrase a paragraph init: Add support for rootwait timeout parameter vfs: fix up the assert in i_readcount_dec fs: Fix one kernel-doc comment docs: filesystems: idmappings: clarify from where idmappings are taken fs/buffer.c: disable per-CPU buffer_head cache for isolated CPUs vfs, security: Fix automount superblock LSM init problem, preventing NFS sb sharing ...
2023-08-25Merge branch 'acpi-thermal'Rafael J. Wysocki
Merge ACPI thermal driver changes for 6.6-rc1: - Drop non-functional nocrt parameter from ACPI thermal (Mario Limonciello). - Clean up the ACPI thermal driver, rework the handling of firmware notifications in it and make it provide a table of generic trip point structures to the core during initialization (Rafael Wysocki). * acpi-thermal: ACPI: thermal: Eliminate code duplication from acpi_thermal_notify() ACPI: thermal: Drop unnecessary thermal zone callbacks ACPI: thermal: Rework thermal_get_trend() ACPI: thermal: Use trip point table to register thermal zones thermal: core: Rework and rename __for_each_thermal_trip() ACPI: thermal: Introduce struct acpi_thermal_trip ACPI: thermal: Carry out trip point updates under zone lock ACPI: thermal: Clean up acpi_thermal_register_thermal_zone() thermal: core: Add priv pointer to struct thermal_trip thermal: core: Introduce thermal_zone_device_exec() thermal: core: Do not handle trip points with invalid temperature ACPI: thermal: Drop redundant local variable from acpi_thermal_resume() ACPI: thermal: Do not attach private data to ACPI handles ACPI: thermal: Drop enabled flag from struct acpi_thermal_active ACPI: thermal: Drop nocrt parameter
2023-08-24crash: memory and CPU hotplug sysfs attributesEric DeVolder
Introduce the crash_hotplug attribute for memory and CPUs for use by userspace. These attributes directly facilitate the udev rule for managing userspace re-loading of the crash kernel upon hot un/plug changes. For memory, expose the crash_hotplug attribute to the /sys/devices/system/memory directory. For example: # udevadm info --attribute-walk /sys/devices/system/memory/memory81 looking at device '/devices/system/memory/memory81': KERNEL=="memory81" SUBSYSTEM=="memory" DRIVER=="" ATTR{online}=="1" ATTR{phys_device}=="0" ATTR{phys_index}=="00000051" ATTR{removable}=="1" ATTR{state}=="online" ATTR{valid_zones}=="Movable" looking at parent device '/devices/system/memory': KERNELS=="memory" SUBSYSTEMS=="" DRIVERS=="" ATTRS{auto_online_blocks}=="offline" ATTRS{block_size_bytes}=="8000000" ATTRS{crash_hotplug}=="1" For CPUs, expose the crash_hotplug attribute to the /sys/devices/system/cpu directory. For example: # udevadm info --attribute-walk /sys/devices/system/cpu/cpu0 looking at device '/devices/system/cpu/cpu0': KERNEL=="cpu0" SUBSYSTEM=="cpu" DRIVER=="processor" ATTR{crash_notes}=="277c38600" ATTR{crash_notes_size}=="368" ATTR{online}=="1" looking at parent device '/devices/system/cpu': KERNELS=="cpu" SUBSYSTEMS=="" DRIVERS=="" ATTRS{crash_hotplug}=="1" ATTRS{isolated}=="" ATTRS{kernel_max}=="8191" ATTRS{nohz_full}==" (null)" ATTRS{offline}=="4-7" ATTRS{online}=="0-3" ATTRS{possible}=="0-7" ATTRS{present}=="0-3" With these sysfs attributes in place, it is possible to efficiently instruct the udev rule to skip crash kernel reloading for kernels configured with crash hotplug support. For example, the following is the proposed udev rule change for RHEL system 98-kexec.rules (as the first lines of the rule file): # The kernel updates the crash elfcorehdr for CPU and memory changes SUBSYSTEM=="cpu", ATTRS{crash_hotplug}=="1", GOTO="kdump_reload_end" SUBSYSTEM=="memory", ATTRS{crash_hotplug}=="1", GOTO="kdump_reload_end" When examined in the context of 98-kexec.rules, the above rules test if crash_hotplug is set, and if so, the userspace initiated unload-then-reload of the crash kernel is skipped. CPU and memory checks are separated in accordance with CONFIG_HOTPLUG_CPU and CONFIG_MEMORY_HOTPLUG kernel config options. If an architecture supports, for example, memory hotplug but not CPU hotplug, then the /sys/devices/system/memory/crash_hotplug attribute file is present, but the /sys/devices/system/cpu/crash_hotplug attribute file will NOT be present. Thus the udev rule skips userspace processing of memory hot un/plug events, but the udev rule will evaluate false for CPU events, thus allowing userspace to process CPU hot un/plug events (ie the unload-then-reload of the kdump capture kernel). Link: https://lkml.kernel.org/r/20230814214446.6659-5-eric.devolder@oracle.com Signed-off-by: Eric DeVolder <eric.devolder@oracle.com> Reviewed-by: Sourabh Jain <sourabhjain@linux.ibm.com> Acked-by: Hari Bathini <hbathini@linux.ibm.com> Acked-by: Baoquan He <bhe@redhat.com> Cc: Akhil Raj <lf32.dev@gmail.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Borislav Petkov (AMD) <bp@alien8.de> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Dave Young <dyoung@redhat.com> Cc: David Hildenbrand <david@redhat.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Mimi Zohar <zohar@linux.ibm.com> Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Cc: Sean Christopherson <seanjc@google.com> Cc: Takashi Iwai <tiwai@suse.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Thomas Weißschuh <linux@weissschuh.net> Cc: Valentin Schneider <vschneid@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-23Merge patch series "riscv: Allow userspace to directly access perf counters"Palmer Dabbelt
Alexandre Ghiti <alexghiti@rivosinc.com> says: riscv used to allow direct access to cycle/time/instret counters, bypassing the perf framework, this patchset intends to allow the user to mmap any counter when accessed through perf. **Important**: The default mode is now user access through perf only, not the legacy so some applications will break. However, we introduce a sysctl perf_user_access like arm64 does, which will allow to switch to the legacy mode described above. This version needs openSBI v1.3 *and* a kernel fix that went upstream lately (https://lore.kernel.org/lkml/20230616114831.3186980-1-maz@kernel.org/T/). * b4-shazam-merge: perf: tests: Adapt mmap-basic.c for riscv tools: lib: perf: Implement riscv mmap support Documentation: admin-guide: Add riscv sysctl_perf_user_access drivers: perf: Implement perf event mmap support in the SBI backend drivers: perf: Implement perf event mmap support in the legacy backend riscv: Prepare for user-space perf event mmap support drivers: perf: Rename riscv pmu sbi driver riscv: Make legacy counter enum match the HW numbering include: riscv: Fix wrong include guard in riscv_pmu.h perf: Fix wrong comment about default event_idx Link: https://lore.kernel.org/r/20230802080328.1213905-1-alexghiti@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-08-22Documentation: devices.txt: Fix minors for ttyCPM*Christophe Leroy
ttyCPM* devices belong to CPM_UART driver at the first place and that driver provides 6 ports. Fixes: e29c3f81eb89 ("Documentation: devices.txt: reconcile serial/ucc_uart minor numers") Cc: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Link: https://lore.kernel.org/r/27d7124cf86157e2a27c2b039e769041994d3f22.1691992627.git.christophe.leroy@csgroup.eu Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-22Documentation: devices.txt: Remove ttySIOC*Christophe Leroy
IOC3 serial driver was removed, remove associated devices from documentation. Fixes: 9c860e4cf708 ("tty/serial: remove the ioc3_serial driver") Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Link: https://lore.kernel.org/r/f13b5c64f8cb6d8f2357d7be14397676b27ac2a2.1691992627.git.christophe.leroy@csgroup.eu Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-22Documentation: devices.txt: Remove ttyIOC*Christophe Leroy
IOC4 serial driver was removed, remove associated devices from documentation. Fixes: a017ef17cfd8 ("tty/serial: remove the ioc4_serial driver") Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Link: https://lore.kernel.org/r/b5deb1222eb92017f0efe5b5cae127ac11983b3d.1691992627.git.christophe.leroy@csgroup.eu Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-21mm: add large_rmappable page flagMatthew Wilcox (Oracle)
Stored in the first tail page's flags, this flag replaces the destructor. That removes the last of the destructors, so remove all references to folio_dtor and compound_dtor. Link: https://lkml.kernel.org/r/20230816151201.3655946-9-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: David Hildenbrand <david@redhat.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com> Cc: Yanteng Si <siyanteng@loongson.cn> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-21mm: remove HUGETLB_PAGE_DTORMatthew Wilcox (Oracle)
We can use a bit in page[1].flags to indicate that this folio belongs to hugetlb instead of using a value in page[1].dtors. That lets folio_test_hugetlb() become an inline function like it should be. We can also get rid of NULL_COMPOUND_DTOR. Link: https://lkml.kernel.org/r/20230816151201.3655946-8-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: David Hildenbrand <david@redhat.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com> Cc: Yanteng Si <siyanteng@loongson.cn> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-21mm/ksm: add pages scanned metricStefan Roesch
ksm currently maintains several statistics, which let you determine how successful KSM is at sharing pages. However it does not contain a metric to determine how much work it does. This commit adds the pages scanned metric. This allows the administrator to determine how many pages have been scanned over a period of time. Link: https://lkml.kernel.org/r/20230811193655.2518943-1-shr@devkernel.io Signed-off-by: Stefan Roesch <shr@devkernel.io> Acked-by: David Hildenbrand <david@redhat.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Rik van Riel <riel@surriel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-21mm/memory_hotplug: support memmap_on_memory when memmap is not aligned to ↵Aneesh Kumar K.V
pageblocks Currently, memmap_on_memory feature is only supported with memory block sizes that result in vmemmap pages covering full page blocks. This is because memory onlining/offlining code requires applicable ranges to be pageblock-aligned, for example, to set the migratetypes properly. This patch helps to lift that restriction by reserving more pages than required for vmemmap space. This helps the start address to be page block aligned with different memory block sizes. Using this facility implies the kernel will be reserving some pages for every memoryblock. This allows the memmap on memory feature to be widely useful with different memory block size values. For ex: with 64K page size and 256MiB memory block size, we require 4 pages to map vmemmap pages, To align things correctly we end up adding a reserve of 28 pages. ie, for every 4096 pages 28 pages get reserved. Link: https://lkml.kernel.org/r/20230808091501.287660-5-aneesh.kumar@linux.ibm.com Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: David Hildenbrand <david@redhat.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Vishal Verma <vishal.l.verma@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-21Docs/admin-guide/mm/damon/usage: update for DAMON monitoring target type ↵SeongJae Park
DAMOS filter Update DAMON usage document for newly added DAMON monitoring target type DAMOS filter. Link: https://lkml.kernel.org/r/20230802214312.110532-14-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Brendan Higgins <brendanhiggins@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Shuah Khan <shuah@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-21Docs/admin-guide/mm/damon/usage: update for address range type DAMOS filterSeongJae Park
Update DAMON usage document for the newly added address range type DAMOS filter. Link: https://lkml.kernel.org/r/20230802214312.110532-8-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Brendan Higgins <brendanhiggins@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Shuah Khan <shuah@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-21Docs/admin-guide/mm/damon/usage: update for tried_regions/total_bytesSeongJae Park
Update the DAMON usage document for newly added schemes/.../tried_regions/total_bytes file and the update_schemes_tried_bytes command. Link: https://lkml.kernel.org/r/20230802213222.109841-6-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Shuah Khan <shuah@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-21mm: kill frontswapJohannes Weiner
The only user of frontswap is zswap, and has been for a long time. Have swap call into zswap directly and remove the indirection. [hannes@cmpxchg.org: remove obsolete comment, per Yosry] Link: https://lkml.kernel.org/r/20230719142832.GA932528@cmpxchg.org [fengwei.yin@intel.com: don't warn if none swapcache folio is passed to zswap_load] Link: https://lkml.kernel.org/r/20230810095652.3905184-1-fengwei.yin@intel.com Link: https://lkml.kernel.org/r/20230717160227.GA867137@cmpxchg.org Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Yin Fengwei <fengwei.yin@intel.com> Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Acked-by: Nhat Pham <nphamcs@gmail.com> Acked-by: Yosry Ahmed <yosryahmed@google.com> Acked-by: Christoph Hellwig <hch@lst.de> Cc: Domenico Cerasuolo <cerasuolodomenico@gmail.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Vitaly Wool <vitaly.wool@konsulko.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-18Documentation: Fix typosBjorn Helgaas
Fix typos in Documentation. Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Link: https://lore.kernel.org/r/20230814212822.193684-4-helgaas@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2023-08-18mm/memory_hotplug: document the signal_pending() check in offline_pages()David Hildenbrand
Let's update the documentation that any signal is sufficient, and add a comment that not only checking for fatal signals is historical baggage: changing it now could break existing user space. although unlikely. For example, when an app provides a custom SIGALRM handler and triggers memory offlining, the timeout cmd would no longer stop memory offlining, because SIGALRM would no longer be considered a fatal signal. Note that using signal_pending() instead of fatal_signal_pending() is an anti-pattern, but slowly deprecating that behavior to eventually change it in the far future is probably not worth the effort. If this ever becomes relevant for user-space, we might want to rethink. Link: https://lkml.kernel.org/r/20230711174050.603820-1-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-18mm: userfaultfd: document and enable new UFFDIO_POISON featureAxel Rasmussen
Update the userfaultfd API to advertise this feature as part of feature flags and supported ioctls (returned upon registration). Add basic documentation describing the new feature. Link: https://lkml.kernel.org/r/20230707215540.2324998-7-axelrasmussen@google.com Signed-off-by: Axel Rasmussen <axelrasmussen@google.com> Acked-by: Peter Xu <peterx@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Brian Geffon <bgeffon@google.com> Cc: Christian Brauner <brauner@kernel.org> Cc: David Hildenbrand <david@redhat.com> Cc: Gaosheng Cui <cuigaosheng1@huawei.com> Cc: Huang, Ying <ying.huang@intel.com> Cc: Hugh Dickins <hughd@google.com> Cc: James Houghton <jthoughton@google.com> Cc: Jan Alexander Steffens (heftig) <heftig@archlinux.org> Cc: Jiaqi Yan <jiaqiyan@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Miaohe Lin <linmiaohe@huawei.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Mike Rapoport (IBM) <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nadav Amit <namit@vmware.com> Cc: Naoya Horiguchi <naoya.horiguchi@nec.com> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Suleiman Souhlal <suleiman@google.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: T.J. Alumbaugh <talumbau@google.com> Cc: Yu Zhao <yuzhao@google.com> Cc: ZhangPeng <zhangpeng362@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-18memcg: drop kmem.limit_in_bytesMichal Hocko
kmem.limit_in_bytes (v1 way to limit kernel memory usage) has been deprecated since 58056f77502f ("memcg, kmem: further deprecate kmem.limit_in_bytes") merged in 5.16. We haven't heard about any serious users since then but it seems that the mere presence of the file is causing more harm thatn good. We (SUSE) have had several bug reports from customers where Docker based containers started to fail because a write to kmem.limit_in_bytes has failed. This was unexpected because runc code only expects ENOENT (kmem disabled) or EBUSY (tasks already running within cgroup). So a new error code was unexpected and the whole container startup failed. This has been later addressed by https://github.com/opencontainers/runc/commit/52390d68040637dfc77f9fda6bbe70952423d380 so current Docker runtimes do not suffer from the problem anymore. There are still older version of Docker in use and likely hard to get rid of completely. Address this by wiping out the file completely and effectively get back to pre 4.5 era and CONFIG_MEMCG_KMEM=n configuration. I would recommend backporting to stable trees which have picked up 58056f77502f ("memcg, kmem: further deprecate kmem.limit_in_bytes"). [mhocko@suse.com: restore _KMEM switch case] Link: https://lkml.kernel.org/r/ZKe5wxdbvPi5Cwd7@dhcp22.suse.cz Link: https://lkml.kernel.org/r/20230704115240.14672-1-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Acked-by: Shakeel Butt <shakeelb@google.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Roman Gushchin <roman.gushchin@linux.dev> Cc: Muchun Song <muchun.song@linux.dev> Cc: Tejun Heo <tj@kernel.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-18ksm: consider KSM-placed zeropages when calculating KSM profitxu xin
When use_zero_pages is enabled, the calculation of ksm profit is not correct because ksm zero pages is not counted in. So update the calculation of KSM profit including the documentation. Link: https://lkml.kernel.org/r/20230613030942.186041-1-yang.yang29@zte.com.cn Signed-off-by: xu xin <xu.xin16@zte.com.cn> Acked-by: David Hildenbrand <david@redhat.com> Cc: Xiaokai Ran <ran.xiaokai@zte.com.cn> Cc: Yang Yang <yang.yang29@zte.com.cn> Cc: Jiang Xuexin <jiang.xuexin@zte.com.cn> Cc: Claudio Imbrenda <imbrenda@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-18ksm: count all zero pages placed by KSMxu xin
As pages_sharing and pages_shared don't include the number of zero pages merged by KSM, we cannot know how many pages are zero pages placed by KSM when enabling use_zero_pages, which leads to KSM not being transparent with all actual merged pages by KSM. In the early days of use_zero_pages, zero-pages was unable to get unshared by the ways like MADV_UNMERGEABLE so it's hard to count how many times one of those zeropages was then unmerged. But now, unsharing KSM-placed zero page accurately has been achieved, so we can easily count both how many times a page full of zeroes was merged with zero-page and how many times one of those pages was then unmerged. and so, it helps to estimate memory demands when each and every shared page could get unshared. So we add ksm_zero_pages under /sys/kernel/mm/ksm/ to show the number of all zero pages placed by KSM. Meanwhile, we update the Documentation. Link: https://lkml.kernel.org/r/20230613030934.185944-1-yang.yang29@zte.com.cn Signed-off-by: xu xin <xu.xin16@zte.com.cn> Acked-by: David Hildenbrand <david@redhat.com> Cc: Claudio Imbrenda <imbrenda@linux.ibm.com> Cc: Xuexin Jiang <jiang.xuexin@zte.com.cn> Reviewed-by: Xiaokai Ran <ran.xiaokai@zte.com.cn> Reviewed-by: Yang Yang <yang.yang29@zte.com.cn> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-18docs: kernel-parameters: Refer to the correct bitmap functionAndy Shevchenko
The parser of the CPU lists is bitmap_parselist() that supports special notations with the plain numbers. bitmap_parse() never supported those and will fail in case one will try it. Fixes: b18def121f07 ("bitmap_parse: Support 'all' semantics") Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20230817140432.507889-1-andriy.shevchenko@linux.intel.com
2023-08-18doc: update params of memhp_default_state=Ma Wupeng
Commit 5f47adf762b7 ("mm/memory_hotplug: allow to specify a default online_type") allows to specify a default online_type which make online memory to kernel or movable zone possible but fail to update to doc. Update doc to fit this change. Signed-off-by: Ma Wupeng <mawupeng1@huawei.com> Reviewed-by: David Hildenbrand <david@redhat.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20230802074312.2111074-1-mawupeng1@huawei.com
2023-08-18powerpc/idle: Add support for nohltVaibhav Jain
This patch enables config option GENERIC_IDLE_POLL_SETUP for arch powerpc. This adds support for kernel param 'nohlt'. Powerpc kernel also supports another kernel boot-time param called 'powersave' which can also be used to disable all cpu idle-states and forces CPU to an idle-loop similar to what cpu_idle_poll() does. This patch however makes powerpc kernel-parameters better aligned to the generic boot-time parameters. Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230818050739.827851-1-vaibhav@linux.ibm.com
2023-08-17tpm_tis: Revert "tpm_tis: Disable interrupts on ThinkPad T490s"Jarkko Sakkinen
Since for MMIO driver using FIFO registers, also known as tpm_tis, the default (and tbh recommended) behaviour is now the polling mode, the "tristate" workaround is no longer for benefit. If someone wants to explicitly enable IRQs for a TPM chip that should be without question allowed. It could very well be a piece hardware in the existing deny list because of e.g. firmware update or something similar. While at it, document the module parameter, as this was not done in 2006 when it first appeared in the mainline. Link: https://lore.kernel.org/linux-integrity/20201015214430.17937-1-jsnitsel@redhat.com/ Link: https://lore.kernel.org/all/1145393776.4829.19.camel@localhost.localdomain/ Reviewed-by: Jerry Snitselaar <jsnitsel@redhat.com> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2023-08-16Merge branches 'doc.2023.07.14b', 'fixes.2023.08.16a', ↵Paul E. McKenney
'rcu-tasks.2023.07.24a', 'rcuscale.2023.07.14b', 'refscale.2023.07.14b', 'torture.2023.08.14a' and 'torturescripts.2023.07.20a' into HEAD doc.2023.07.14b: Documentation updates. fixes.2023.08.16a: Miscellaneous fixes. rcu-tasks.2023.07.24a: RCU Tasks updates. rcuscale.2023.07.14b: RCU (updater) scalability test updates. refscale.2023.07.14b: Reference (reader) scalability test updates. torture.2023.08.14a: Other torture-test updates. torturescripts.2023.07.20a: Other torture-test scripting updates.
2023-08-16x86/cpu: Rename srso_(.*)_alias to srso_alias_\1Peter Zijlstra
For a more consistent namespace. [ bp: Fixup names in the doc too. ] Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20230814121148.976236447@infradead.org
2023-08-16docs: kdump: Update the crashkernel description for riscvChen Jiahao
Now "crashkernel=" parameter on riscv has been updated to support crashkernel=X,[high,low]. Through which we can reserve memory region above/within 32bit addressible DMA zone. Here update the parameter description accordingly. Signed-off-by: Chen Jiahao <chenjiahao16@huawei.com> Reviewed-by: Guo Ren <guoren@kernel.org> Reviewed-by: Simon Horman <horms@kernel.org> Reviewed-by: Zhen Lei <thunder.leizhen@huawei.com> Acked-by: Baoquan He <bhe@redhat.com> Link: https://lore.kernel.org/r/20230726175000.2536220-3-chenjiahao16@huawei.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-08-16Documentation: admin-guide: Add riscv sysctl_perf_user_accessAlexandre Ghiti
riscv now uses this sysctl so document its usage for this architecture. Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
2023-08-15init: Add support for rootwait timeout parameterLoic Poulain
Add an optional timeout arg to 'rootwait' as the maximum time in seconds to wait for the root device to show up before attempting forced mount of the root filesystem. Use case: In case of device mapper usage for the rootfs (e.g. root=/dev/dm-0), if the mapper is not able to create the virtual block for any reason (wrong arguments, bad dm-verity signature, etc), the `rootwait` param causes the kernel to wait forever. It may however be desirable to only wait for a given time and then panic (force mount) to cause device reset. This gives the bootloader a chance to detect the problem and to take some measures, such as marking the booted partition as bad (for A/B case) or entering a recovery mode. In success case, mounting happens as soon as the root device is ready, unlike the existing 'rootdelay' parameter which performs an unconditional pause. Signed-off-by: Loic Poulain <loic.poulain@linaro.org> Message-Id: <20230813082349.513386-1-loic.poulain@linaro.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-08-14torture: Add lock_torture writer_fifo module parameterDietmar Eggemann
This commit adds a module parameter that causes the locktorture writer to run at real-time priority. To use it: insmod /lib/modules/torture.ko random_shuffle=1 insmod /lib/modules/locktorture.ko torture_type=mutex_lock rt_boost=1 rt_boost_factor=50 nested_locks=3 writer_fifo=1 ^^^^^^^^^^^^^ A predecessor to this patch has been helpful to uncover issues with the proxy-execution series. [ paulmck: Remove locktorture-specific code from kernel/torture.c. ] Cc: "Paul E. McKenney" <paulmck@kernel.org> Cc: Josh Triplett <josh@joshtriplett.org> Cc: Joel Fernandes <joel@joelfernandes.org> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Valentin Schneider <vschneid@redhat.com> Cc: kernel-team@android.com Signed-off-by: Dietmar Eggemann <dietmar.eggemann@arm.com> [jstultz: Include header change to build, reword commit message] Signed-off-by: John Stultz <jstultz@google.com> Acked-by: Davidlohr Bueso <dave@stgolabs.net> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2023-08-14Merge 6.5-rc6 into usb-nextGreg Kroah-Hartman
We need the USB and Thunderbolt fixes in here to build on. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-13Merge 6.5-rc6 into char-misc-nextGreg Kroah-Hartman
We need the char/misc fixes in here as well to build on top of. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-10Merge remote-tracking branch 'torvalds/master' into perf-tools-nextArnaldo Carvalho de Melo
To pick up some more fixes that went upstream via the perf-tools fixes branch. Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-08-10Documentation/srso: Document IBPB aspect and fix formattingBorislav Petkov (AMD)
Add a note about the dependency of the User->User mitigation on the previous Spectre v2 IBPB selection. Make the layout moar pretty. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://lore.kernel.org/r/20230809102700.29449-4-bp@alien8.de
2023-08-10Documentation/hw-vuln: Unify filename specification in indexBorislav Petkov (AMD)
Most of the index.rst files in Documentation/ refer to other rst files without their file extension in the name. Do that here too. No functional changes. Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://lore.kernel.org/r/20230809102700.29449-2-bp@alien8.de
2023-08-09USB: Remove Wireless USB and UWB documentationAlan Stern
Support for Wireless USB and Ultra WideBand was removed in 2020 by commit caa6772db4c1 ("Staging: remove wusbcore and UWB from the kernel tree."). But the documentation files were left behind. Let's get rid of that out-of-date documentation. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Link: https://lore.kernel.org/r/015d4310-bcd3-4ba4-9a0e-3664f281a9be@rowland.harvard.edu Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-07workqueue: Make default affinity_scope dynamically updatableTejun Heo
While workqueue.default_affinity_scope is writable, it only affects workqueues which are created afterwards and isn't very useful. Instead, let's introduce explicit "default" scope and update the effective scope dynamically when workqueue.default_affinity_scope is changed. Signed-off-by: Tejun Heo <tj@kernel.org>
2023-08-07workqueue: Add multiple affinity scopes and interface to select themTejun Heo
Add three more affinity scopes - WQ_AFFN_CPU, SMT and CACHE - and make CACHE the default. The code changes to actually add the additional scopes are trivial. Also add module parameter "workqueue.default_affinity_scope" to override the default scope and "affinity_scope" sysfs file to configure it per workqueue. wq_dump.py and documentations are updated accordingly. This enables significant flexibility in configuring how unbound workqueues behave. If affinity scope is set to "cpu", it'll behave close to a per-cpu workqueue. On the other hand, "system" removes all locality boundaries. Many modern machines have multiple L3 caches often while being mostly uniform in terms of memory access. Thus, workqueue's previous behavior of spreading work items in each NUMA node had negative performance implications from unncessarily crossing L3 boundaries between issue and execution. However, picking a finer grained affinity scope also has a downside in that an issuer in one group can't utilize CPUs in other groups. While dependent on the specifics of workload, there's usually a noticeable penalty in crossing L3 boundaries, so let's default to CACHE. This issue will be further addressed and documented with examples in future patches. Signed-off-by: Tejun Heo <tj@kernel.org>
2023-08-07workqueue: Remove module param disable_numa and sysfs knobs pool_ids and numaTejun Heo
Unbound workqueue CPU affinity is going to receive an overhaul and the NUMA specific knobs won't make sense anymore. Remove them. Also, the pool_ids knob was used for debugging and not really meaningful given that there is no visibility into the pools associated with those IDs. Remove it too. A future patch will improve overall visibility. Signed-off-by: Tejun Heo <tj@kernel.org>
2023-08-07Merge tag 'gds-for-linus-2023-08-01' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86/gds fixes from Dave Hansen: "Mitigate Gather Data Sampling issue: - Add Base GDS mitigation - Support GDS_NO under KVM - Fix a documentation typo" * tag 'gds-for-linus-2023-08-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: Documentation/x86: Fix backwards on/off logic about YMM support KVM: Add GDS_NO support to KVM x86/speculation: Add Kconfig option for GDS x86/speculation: Add force option to GDS mitigation x86/speculation: Add Gather Data Sampling mitigation
2023-08-07Merge tag 'x86_bugs_srso' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86/srso fixes from Borislav Petkov: "Add a mitigation for the speculative RAS (Return Address Stack) overflow vulnerability on AMD processors. In short, this is yet another issue where userspace poisons a microarchitectural structure which can then be used to leak privileged information through a side channel" * tag 'x86_bugs_srso' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/srso: Tie SBPB bit setting to microcode patch detection x86/srso: Add a forgotten NOENDBR annotation x86/srso: Fix return thunks in generated code x86/srso: Add IBPB on VMEXIT x86/srso: Add IBPB x86/srso: Add SRSO_NO support x86/srso: Add IBPB_BRTYPE support x86/srso: Add a Speculative RAS Overflow mitigation x86/bugs: Increase the x86 bugs vector size to two u32s
2023-08-04Merge tag 'riscv-for-linus-6.5-rc5' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V fixes from Palmer Dabbelt: - A pair of fixes for build-related failures in the selftests - A fix for a sparse warning in acpi_os_ioremap() - A fix to restore the kernel PA offset in vmcoreinfo, to fix crash handling * tag 'riscv-for-linus-6.5-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: Documentation: kdump: Add va_kernel_pa_offset for RISCV64 riscv: Export va_kernel_pa_offset in vmcoreinfo RISC-V: ACPI: Fix acpi_os_ioremap to return iomem address selftests: riscv: Fix compilation error with vstate_exec_nolibc.c selftests/riscv: fix potential build failure during the "emit_tests" step
2023-08-04dyndbg: add source filename to prefixThomas Weißschuh
Printing the line number without the file is of limited usefulness. Knowing the filename also makes it also easier to relate the logged information to the controlfile. Example: # modprobe test_dynamic_debug # echo 'file test_dynamic_debug.c =pfsl' > /proc/dynamic_debug/control # echo 1 > /sys/module/test_dynamic_debug/parameters/do_prints # dmesg | tail -2 [ 71.802212] do_cats:lib/test_dynamic_debug.c:103: test_dd: doing categories [ 71.802227] do_levels:lib/test_dynamic_debug.c:123: test_dd: doing levels Signed-off-by: Thomas Weißschuh <linux@weissschuh.net> Acked-by: Jim Cromie <jim.cromie@gmail.com> Acked-by: Jason Baron <jbaron@akamai.com> Reviewed-by: Luis Chamberlain <mcgrof@kernel.org> Link: https://lore.kernel.org/r/20230709-dyndbg-filename-v2-3-fd83beef0925@weissschuh.net Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-04Merge remote-tracking branch 'torvalds/master' into perf-tools-nextArnaldo Carvalho de Melo
To pick up the fixes that were just merged from perf-tools/perf-tools for v6.5. Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-08-03Documentation: cgroup-v2.rst: Correct number of stats entriesHan Dapeng
Signed-off-by: Han Dapeng <han-dapeng@foxmail.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2023-08-02Documentation: kdump: Add va_kernel_pa_offset for RISCV64Song Shuai
RISC-V Linux exports "va_kernel_pa_offset" in vmcoreinfo to help Crash-utility translate the kernel virtual address correctly. Here adds the definition of "va_kernel_pa_offset". Fixes: 3335068f8721 ("riscv: Use PUD/P4D/PGD pages for the linear mapping") Link: https://lore.kernel.org/linux-riscv/20230724040649.220279-1-suagrfillet@gmail.com/ Signed-off-by: Song Shuai <suagrfillet@gmail.com> Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com> Link: https://lore.kernel.org/r/20230724100917.309061-2-suagrfillet@gmail.com Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-08-02powerpc: Add HOTPLUG_SMT supportMichael Ellerman
Add support for HOTPLUG_SMT, which enables the generic sysfs SMT support files in /sys/devices/system/cpu/smt, as well as the "nosmt" boot parameter. Implement the recently added hooks to allow partial SMT states, allow any number of threads per core. Tie the config symbol to HOTPLUG_CPU, which enables it on the major platforms that support SMT. If there are other platforms that want the SMT support that can be tweaked in future. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> [ldufour: remove topology_smt_supported] [ldufour: remove topology_smt_threads_supported] [ldufour: select CONFIG_SMT_NUM_THREADS_DYNAMIC] [ldufour: update kernel-parameters.txt] Signed-off-by: Laurent Dufour <ldufour@linux.ibm.com> Link: https://msgid.link/20230705145143.40545-10-ldufour@linux.ibm.com
2023-08-01Documentation/x86: Fix backwards on/off logic about YMM supportDave Hansen
These options clearly turn *off* XSAVE YMM support. Correct the typo. Reported-by: Ben Hutchings <ben@decadent.org.uk> Fixes: 553a5c03e90a ("x86/speculation: Add force option to GDS mitigation") Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
2023-07-31Docs: kernel-parameters: sort the LEGEND listRandy Dunlap
Sort the list of kernel build options and hardware support options. Add a comment that the list should be kept sorted instead of having new options inserted willy nilly. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20230725174247.32393-1-rdunlap@infradead.org