aboutsummaryrefslogtreecommitdiff
path: root/Documentation/admin-guide
AgeCommit message (Collapse)AuthorFilesLines
2021-12-25Merge branch 'for-linus' of ↵Linus Torvalds1-0/+2
git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input Pull input fixes from Dmitry Torokhov: "A few small updates to drivers. Of note we are now deferring probes of i8042 on some Asus devices as the controller is not ready to respond to queries first time around when the driver is compiled into the kernel" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: Input: elants_i2c - do not check Remark ID on eKTH3900/eKTH5312 Input: atmel_mxt_ts - fix double free in mxt_read_info_block Input: goodix - fix memory leak in goodix_firmware_upload Input: goodix - add id->model mapping for the "9111" model Input: goodix - try not to touch the reset-pin on x86/ACPI devices Input: i8042 - enable deferred probe quirk for ASUS UM325UA Input: elantech - fix stack out of bound access in elantech_change_report_id() Input: iqs626a - prohibit inlining of channel parsing functions Input: i8042 - add deferred probe support
2021-12-21Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds1-2/+6
Pull kvm fixes from Paolo Bonzini: - Fix for compilation of selftests on non-x86 architectures - Fix for kvm_run->if_flag on SEV-ES - Fix for page table use-after-free if yielding during exit_mm() - Improve behavior when userspace starts a nested guest with invalid state - Fix missed wakeup with assigned devices but no VT-d posted interrupts - Do not tell userspace to save/restore an unsupported PMU MSR * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: VMX: Wake vCPU when delivering posted IRQ even if vCPU == this vCPU KVM: selftests: Add test to verify TRIPLE_FAULT on invalid L2 guest state KVM: VMX: Fix stale docs for kvm-intel.emulate_invalid_guest_state KVM: nVMX: Synthesize TRIPLE_FAULT for L2 if emulation is required KVM: VMX: Always clear vmx->fail on emulation_required selftests: KVM: Fix non-x86 compiling KVM: x86: Always set kvm_run->if_flag KVM: x86/mmu: Don't advance iterator after restart due to yielding KVM: x86: remove PMU FIXED_CTR3 from msrs_to_save_all
2021-12-20KVM: VMX: Fix stale docs for kvm-intel.emulate_invalid_guest_stateSean Christopherson1-2/+6
Update the documentation for kvm-intel's emulate_invalid_guest_state to rectify the description of KVM's default behavior, and to document that the behavior and thus parameter only applies to L1. Fixes: a27685c33acc ("KVM: VMX: Emulate invalid guest state by default") Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20211207193006.120997-4-seanjc@google.com> Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-12-06Merge tag 'docs-5.16-3' of git://git.lwn.net/linuxLinus Torvalds2-7/+2
Pull documentation fixes from Jonathan Corbet: "A few important documentation fixes, including breakage that comes with v1.0 of the ReadTheDocs theme" * tag 'docs-5.16-3' of git://git.lwn.net/linux: Documentation: Add minimum pahole version Documentation/process: fix self reference docs: admin-guide/blockdev: Remove digraph of node-states docs: conf.py: fix support for Readthedocs v 1.0.0
2021-11-29docs: admin-guide/blockdev: Remove digraph of node-statesAkira Yokosawa2-7/+2
While node-states-8.dot has two digraphs, the dot(1) command can not properly handle multiple graphs in a DOT file and the kernel-doc page at https://www.kernel.org/doc/html/latest/admin-guide/blockdev/drbd/figures.html fails to render the graphs. It turned out that the digraph of node_states can be removed. Quote from Joel's reflection: On reflection, the digraph node_states can be removed entirely. It is too basic to contain any useful information. In addition it references "ioctl_set_state". The ioctl configuration interface for DRBD has long been removed. In fact, it was never in the upstream version of DRBD. Remove node_states and rename the DOT file peer_states-8.dot. Suggested-by: Joel Colledge <joel.colledge@linbit.com> Acked-by: Joel Colledge <joel.colledge@linbit.com> Signed-off-by: Akira Yokosawa <akiyks@gmail.com> Cc: Philipp Reisner <philipp.reisner@linbit.com> Cc: Lars Ellenberg <lars.ellenberg@linbit.com> Link: https://lore.kernel.org/r/7df04f45-8746-e666-1a9d-a998f1ab1f91@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-11-28Input: i8042 - add deferred probe supportTakashi Iwai1-0/+2
We've got a bug report about the non-working keyboard on ASUS ZenBook UX425UA. It seems that the PS/2 device isn't ready immediately at boot but takes some seconds to get ready. Until now, the only workaround is to defer the probe, but it's available only when the driver is a module. However, many distros, including openSUSE as in the original report, build the PS/2 input drivers into kernel, hence it won't work easily. This patch adds the support for the deferred probe for i8042 stuff as a workaround of the problem above. When the deferred probe mode is enabled and the device couldn't be probed, it'll be repeated with the standard deferred probe mechanism. The deferred probe mode is enabled either via the new option i8042.probe_defer or via the quirk table entry. As of this patch, the quirk table contains only ASUS ZenBook UX425UA. The deferred probe part is based on Fabio's initial work. BugLink: https://bugzilla.suse.com/show_bug.cgi?id=1190256 Signed-off-by: Takashi Iwai <tiwai@suse.de> Tested-by: Samuel Čavoj <samuel@cavoj.net> Link: https://lore.kernel.org/r/20211117063757.11380-1-tiwai@suse.de Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2021-11-18Merge tag 'platform-drivers-x86-v5.16-2' of ↵Linus Torvalds1-6/+6
git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86 Pull x86 platform driver fixes from Hans de Goede: "Various build- and bug-fixes as well as one hardware-id addition" * tag 'platform-drivers-x86-v5.16-2' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86: platform/x86: thinkpad_acpi: fix documentation for adaptive keyboard platform/x86: thinkpad_acpi: Fix WWAN device disabled issue after S3 deep platform/x86: thinkpad_acpi: Add support for dual fan control platform/x86: think-lmi: Abort probe on analyze failure platform/x86: dell-wmi-descriptor: disable by default platform/x86: samsung-laptop: Fix typo in a comment platform/x86: hp_accel: Fix an error handling path in 'lis3lv02d_probe()' platform/x86: amd-pmc: Make CONFIG_AMD_PMC depend on RTC_CLASS platform/mellanox: mlxreg-lc: fix error code in mlxreg_lc_create_static_devices()
2021-11-17docs: accounting: update delay-accounting.rst referenceMauro Carvalho Chehab1-1/+1
The file name: accounting/delay-accounting.rst should be, instead: Documentation/accounting/delay-accounting.rst. Also, there's no need to use doc:`foo`, as automarkup.py will automatically handle plain text mentions to Documentation/ files. So, update its cross-reference accordingly. Fixes: fcb501704554 ("delayacct: Document task_delayacct sysctl") Fixes: c3123552aad3 ("docs: accounting: convert to ReST") Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-11-16platform/x86: thinkpad_acpi: fix documentation for adaptive keyboardVincent Bernat1-6/+6
The different values were offset by 1. 0 is for "home mode", 1 for "web-browser mode", etc. Moreover, the URL to the laptop's user guide did not work anymore. Signed-off-by: Vincent Bernat <vincent@bernat.ch> Link: https://lore.kernel.org/r/20211109195209.176905-1-vincent@bernat.ch Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2021-11-10Merge tag 'nfsd-5.16' of git://linux-nfs.org/~bfields/linuxLinus Torvalds1-0/+14
Pull nfsd updates from Bruce Fields: "A slow cycle for nfsd: mainly cleanup, including Neil's patch dropping support for a filehandle format deprecated 20 years ago, and further xdr-related cleanup from Chuck" * tag 'nfsd-5.16' of git://linux-nfs.org/~bfields/linux: (26 commits) nfsd4: remove obselete comment nfsd: document server-to-server-copy parameters NFSD:fix boolreturn.cocci warning nfsd: update create verifier comment SUNRPC: Change return value type of .pc_encode SUNRPC: Replace the "__be32 *p" parameter to .pc_encode NFSD: Save location of NFSv4 COMPOUND status SUNRPC: Change return value type of .pc_decode SUNRPC: Replace the "__be32 *p" parameter to .pc_decode SUNRPC: De-duplicate .pc_release() call sites SUNRPC: Simplify the SVC dispatch code path SUNRPC: Capture value of xdr_buf::page_base SUNRPC: Add trace event when alloc_pages_bulk() makes no progress svcrdma: Split svcrmda_wc_{read,write} tracepoints svcrdma: Split the svcrdma_wc_send() tracepoint svcrdma: Split the svcrdma_wc_receive() tracepoint NFSD: Have legacy NFSD WRITE decoders use xdr_stream_subsegment() SUNRPC: xdr_stream_subsegment() must handle non-zero page_bases NFSD: Initialize pointer ni with NULL and not plain integer 0 NFSD: simplify struct nfsfh ...
2021-11-10Merge tag 'kernel.sys.v5.16' of ↵Linus Torvalds1-2/+3
git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux Pull prctl updates from Christian Brauner: "This contains the missing prctl uapi pieces for PR_SCHED_CORE. In order to activate core scheduling the caller is expected to specify the scope of the new core scheduling domain. For example, passing 2 in the 4th argument of prctl(PR_SCHED_CORE, PR_SCHED_CORE_CREATE, <pid>, 2, 0); would indicate that the new core scheduling domain encompasses all tasks in the process group of <pid>. Specifying 0 would only create a core scheduling domain for the thread identified by <pid> and 2 would encompass the whole thread-group of <pid>. Note, the values 0, 1, and 2 correspond to PIDTYPE_PID, PIDTYPE_TGID, and PIDTYPE_PGID. A first version tried to expose those values directly to which I objected because: - PIDTYPE_* is an enum that is kernel internal which we should not expose to userspace directly. - PIDTYPE_* indicates what a given struct pid is used for it doesn't express a scope. But what the 4th argument of PR_SCHED_CORE prctl() expresses is the scope of the operation, i.e. the scope of the core scheduling domain at creation time. So Eugene's patch now simply introduces three new defines PR_SCHED_CORE_SCOPE_THREAD, PR_SCHED_CORE_SCOPE_THREAD_GROUP, and PR_SCHED_CORE_SCOPE_PROCESS_GROUP. They simply express what happens. This has been on the mailing list for quite a while with all relevant scheduler folks Cced. I announced multiple times that I'd pick this up if I don't see or her anyone else doing it. None of this touches proper scheduler code but only concerns uapi so I think this is fine. With core scheduling being quite common now for vm managers (e.g. moving individual vcpu threads into their own core scheduling domain) and container managers (e.g. moving the init process into its own core scheduling domain and letting all created children inherit it) having to rely on raw numbers passed as the 4th argument in prctl() is a bit annoying and everyone is starting to come up with their own defines" * tag 'kernel.sys.v5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux: uapi/linux/prctl: provide macro definitions for the PR_SCHED_CORE type argument
2021-11-10Merge tag 'for-linus-5.16b-rc1-tag' of ↵Linus Torvalds1-0/+7
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen updates from Juergen Gross: - a series to speed up the boot of Xen PV guests - some cleanups in Xen related code - replacement of license texts with the appropriate SPDX headers and fixing of wrong SPDX headers in Xen header files - a small series making paravirtualized interrupt masking much simpler and at the same time removing complaints of objtool - a fix for Xen ballooning hogging workqueues for too long - enablement of the Xen pciback driver for Arm - some further small fixes/enhancements * tag 'for-linus-5.16b-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: (22 commits) xen/balloon: fix unused-variable warning xen/balloon: rename alloc/free_xenballooned_pages xen/balloon: add late_initcall_sync() for initial ballooning done x86/xen: remove 32-bit awareness from startup_xen xen: remove highmem remnants xen: allow pv-only hypercalls only with CONFIG_XEN_PV x86/xen: remove 32-bit pv leftovers xen-pciback: allow compiling on other archs than x86 x86/xen: switch initial pvops IRQ functions to dummy ones x86/xen: remove xen_have_vcpu_info_placement flag x86/pvh: add prototype for xen_pvh_init() xen: Fix implicit type conversion xen: fix wrong SPDX headers of Xen related headers xen/pvcalls-back: Remove redundant 'flush_workqueue()' calls x86/xen: Remove redundant irq_enter/exit() invocations xen-pciback: Fix return in pm_ctrl_init() xen/x86: restrict PV Dom0 identity mapping xen/x86: there's no highmem anymore in PV mode xen/x86: adjust handling of the L3 user vsyscall special page table xen/x86: adjust xen_set_fixmap() ...
2021-11-06Merge tag 'fsnotify_for_v5.16-rc1' of ↵Linus Torvalds2-0/+79
git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs Pull fsnotify updates from Jan Kara: "Support for reporting filesystem errors through fanotify so that system health monitoring daemons can watch for these and act instead of scraping system logs" * tag 'fsnotify_for_v5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs: (34 commits) samples: remove duplicate include in fs-monitor.c samples: Fix warning in fsnotify sample docs: Fix formatting of literal sections in fanotify docs samples: Make fs-monitor depend on libc and headers docs: Document the FAN_FS_ERROR event samples: Add fs error monitoring example ext4: Send notifications on error fanotify: Allow users to request FAN_FS_ERROR events fanotify: Emit generic error info for error event fanotify: Report fid info for file related file system errors fanotify: WARN_ON against too large file handles fanotify: Add helpers to decide whether to report FID/DFID fanotify: Wrap object_fh inline space in a creator macro fanotify: Support merging of error events fanotify: Support enqueueing of error events fanotify: Pre-allocate pool of error events fanotify: Reserve UAPI bits for FAN_FS_ERROR fsnotify: Support FS_ERROR event type fanotify: Require fid_mode for any non-fd event fanotify: Encode empty file handle when no inode is provided ...
2021-11-06Merge tag 's390-5.16-1' of ↵Linus Torvalds1-0/+12
git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull s390 updates from Vasily Gorbik: - Add support for ftrace with direct call and ftrace direct call samples. - Add support for kernel command lines longer than current 896 bytes and make its length configurable. - Add support for BEAR enhancement facility to improve last breaking event instruction tracking. - Add kprobes sanity checks and testcases to prevent kprobe in the mid of an instruction. - Allow concurrent access to /dev/hwc for the CPUMF users. - Various ftrace / jump label improvements. - Convert unwinder tests to KUnit. - Add s390_iommu_aperture kernel parameter to tweak the limits on concurrently usable DMA mappings. - Add ap.useirq AP module option which can be used to disable interrupt use. - Add add_disk() error handling support to block device drivers. - Drop arch specific and use generic implementation of strlcpy and strrchr. - Several __pa/__va usages fixes. - Various cio, crypto, pci, kernel doc and other small fixes and improvements all over the code. [ Merge fixup as per https://lore.kernel.org/all/YXAqZ%2FEszRisunQw@osiris/ ] * tag 's390-5.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (63 commits) s390: make command line configurable s390: support command lines longer than 896 bytes s390/kexec_file: move kernel image size check s390/pci: add s390_iommu_aperture kernel parameter s390/spinlock: remove incorrect kernel doc indicator s390/string: use generic strlcpy s390/string: use generic strrchr s390/ap: function rework based on compiler warning s390/cio: make ccw_device_dma_* more robust s390/vfio-ap: s390/crypto: fix all kernel-doc warnings s390/hmcdrv: fix kernel doc comments s390/ap: new module option ap.useirq s390/cpumf: Allow multiple processes to access /dev/hwc s390/bitops: return true/false (not 1/0) from bool functions s390: add support for BEAR enhancement facility s390: introduce nospec_uses_trampoline() s390: rename last_break to pgm_last_break s390/ptrace: add last_break member to pt_regs s390/sclp: sort out physical vs virtual pointers usage s390/setup: convert start and end initrd pointers to virtual ...
2021-11-06Merge branch 'akpm' (patches from Andrew)Linus Torvalds13-123/+855
Merge misc updates from Andrew Morton: "257 patches. Subsystems affected by this patch series: scripts, ocfs2, vfs, and mm (slab-generic, slab, slub, kconfig, dax, kasan, debug, pagecache, gup, swap, memcg, pagemap, mprotect, mremap, iomap, tracing, vmalloc, pagealloc, memory-failure, hugetlb, userfaultfd, vmscan, tools, memblock, oom-kill, hugetlbfs, migration, thp, readahead, nommu, ksm, vmstat, madvise, memory-hotplug, rmap, zsmalloc, highmem, zram, cleanups, kfence, and damon)" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (257 commits) mm/damon: remove return value from before_terminate callback mm/damon: fix a few spelling mistakes in comments and a pr_debug message mm/damon: simplify stop mechanism Docs/admin-guide/mm/pagemap: wordsmith page flags descriptions Docs/admin-guide/mm/damon/start: simplify the content Docs/admin-guide/mm/damon/start: fix a wrong link Docs/admin-guide/mm/damon/start: fix wrong example commands mm/damon/dbgfs: add adaptive_targets list check before enable monitor_on mm/damon: remove unnecessary variable initialization Documentation/admin-guide/mm/damon: add a document for DAMON_RECLAIM mm/damon: introduce DAMON-based Reclamation (DAMON_RECLAIM) selftests/damon: support watermarks mm/damon/dbgfs: support watermarks mm/damon/schemes: activate schemes based on a watermarks mechanism tools/selftests/damon: update for regions prioritization of schemes mm/damon/dbgfs: support prioritization weights mm/damon/vaddr,paddr: support pageout prioritization mm/damon/schemes: prioritize regions within the quotas mm/damon/selftests: support schemes quotas mm/damon/dbgfs: support quotas of schemes ...
2021-11-06Docs/admin-guide/mm/pagemap: wordsmith page flags descriptionsSeongJae Park1-26/+27
Some descriptions of page flags in 'pagemap.rst' are written in assumption of none-rst, which respects every new line, as below: 7 - SLAB page is managed by the SLAB/SLOB/SLUB/SLQB kernel memory allocator When compound page is used, SLUB/SLQB will only set this flag on the head Because rst ignores the new line between the first sentence and second sentence, resulting html looks a little bit weird, as below. 7 - SLAB page is managed by the SLAB/SLOB/SLUB/SLQB kernel memory allocator When ^ compound page is used, SLUB/SLQB will only set this flag on the head page; SLOB will not flag it at all. This change makes it more natural and consistent with other parts in the rendered version. Link: https://lkml.kernel.org/r/20211022090311.3856-5-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Peter Xu <peterx@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-06Docs/admin-guide/mm/damon/start: simplify the contentSeongJae Park1-53/+60
Information in 'TL; DR' section of 'Getting Started' is duplicated in other parts of the doc. It is also asking readers to visit the access pattern visualizations gallery web site to show the results of example visualization commands, while the users of the commands can use terminal output. To make the doc simple, this removes the duplicated 'TL; DR' section and replaces the visualization example commands with versions using terminal outputs. Link: https://lkml.kernel.org/r/20211022090311.3856-4-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Peter Xu <peterx@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-06Docs/admin-guide/mm/damon/start: fix a wrong linkSeongJae Park1-1/+3
The 'Getting Started' of DAMON is providing a link to DAMON's user interface document while saying about its user space tool's detailed usages. This fixes the link. Link: https://lkml.kernel.org/r/20211022090311.3856-3-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Peter Xu <peterx@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-06Docs/admin-guide/mm/damon/start: fix wrong example commandsSeongJae Park1-7/+7
Patch series "Fix trivial nits in Documentation/admin-guide/mm". This patchset fixes trivial nits in admin guide documents for DAMON and pagemap. This patch (of 4): Some of the example commands in DAMON getting started guide are outdated, missing sudo, or just wrong. This fixes those. Link: https://lkml.kernel.org/r/20211022090311.3856-2-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Peter Xu <peterx@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-06Documentation/admin-guide/mm/damon: add a document for DAMON_RECLAIMSeongJae Park2-0/+236
This adds an admin-guide document for DAMON-based Reclamation. Link: https://lkml.kernel.org/r/20211019150731.16699-16-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Amit Shah <amit@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: David Hildenbrand <david@redhat.com> Cc: David Rientjes <rientjes@google.com> Cc: David Woodhouse <dwmw@amazon.com> Cc: Greg Thelen <gthelen@google.com> Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Leonard Foerster <foersleo@amazon.de> Cc: Marco Elver <elver@google.com> Cc: Markus Boehme <markubo@amazon.de> Cc: Shakeel Butt <shakeelb@google.com> Cc: Shuah Khan <shuah@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-06Docs/DAMON: document physical memory monitoring supportSeongJae Park1-5/+20
This updates the DAMON documents for the physical memory address space monitoring support. Link: https://lkml.kernel.org/r/20211012205711.29216-8-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Amit Shah <amit@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Brendan Higgins <brendanhiggins@google.com> Cc: David Hildenbrand <david@redhat.com> Cc: David Rienjes <rientjes@google.com> Cc: David Woodhouse <dwmw@amazon.com> Cc: Greg Thelen <gthelen@google.com> Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Leonard Foerster <foersleo@amazon.de> Cc: Marco Elver <elver@google.com> Cc: Markus Boehme <markubo@amazon.de> Cc: Shakeel Butt <shakeelb@google.com> Cc: Shuah Khan <shuah@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-06Docs/admin-guide/mm/damon: document 'init_regions' featureSeongJae Park1-2/+39
This adds description of the 'init_regions' feature in the DAMON usage document. Link: https://lkml.kernel.org/r/20211012205711.29216-4-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Amit Shah <amit@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Brendan Higgins <brendanhiggins@google.com> Cc: David Hildenbrand <david@redhat.com> Cc: David Rienjes <rientjes@google.com> Cc: David Woodhouse <dwmw@amazon.com> Cc: Greg Thelen <gthelen@google.com> Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Leonard Foerster <foersleo@amazon.de> Cc: Marco Elver <elver@google.com> Cc: Markus Boehme <markubo@amazon.de> Cc: Shakeel Butt <shakeelb@google.com> Cc: Shuah Khan <shuah@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-06Docs/admin-guide/mm/damon: document DAMON-based Operation SchemesSeongJae Park2-2/+60
This adds the description of DAMON-based operation schemes in the DAMON documents. Link: https://lkml.kernel.org/r/20211001125604.29660-8-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Amit Shah <amit@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: David Hildenbrand <david@redhat.com> Cc: David Rienjes <rientjes@google.com> Cc: David Woodhouse <dwmw@amazon.com> Cc: Greg Thelen <gthelen@google.com> Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Leonard Foerster <foersleo@amazon.de> Cc: Marco Elver <elver@google.com> Cc: Markus Boehme <markubo@amazon.de> Cc: Shakeel Butt <shakeelb@google.com> Cc: Shuah Khan <shuah@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-06Documentation/vm: move user guides to admin-guide/mm/SeongJae Park3-0/+234
Most memory management user guide documents are in 'admin-guide/mm/', but two of those are in 'vm/'. This moves the two docs into 'admin-guide/mm' for easier documents finding. Link: https://lkml.kernel.org/r/20210917123958.3819-2-sj@kernel.org Signed-off-by: SeongJae Park <sjpark@amazon.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-06zram: introduce an aged idle interfaceBrian Geffon1-0/+8
This change introduces an aged idle interface to the existing idle sysfs file for zram. When CONFIG_ZRAM_MEMORY_TRACKING is enabled the idle file now also accepts an integer argument. This integer is the age (in seconds) of pages to mark as idle. The idle file still supports 'all' as it always has. This new approach allows for much more control over which pages get marked as idle. [bgeffon@google.com: use IS_ENABLED and cleanup comment] Link: https://lkml.kernel.org/r/20210924161128.1508015-1-bgeffon@google.com [bgeffon@google.com: Sergey's cleanup suggestions] Link: https://lkml.kernel.org/r/20210929143056.13067-1-bgeffon@google.com Link: https://lkml.kernel.org/r/20210923130115.1344361-1-bgeffon@google.com Signed-off-by: Brian Geffon <bgeffon@google.com> Acked-by: Minchan Kim <minchan@kernel.org> Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Suleiman Souhlal <suleiman@google.com> Cc: Jesse Barnes <jsbarnes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-06memory-hotplug.rst: document the "auto-movable" online policyDavid Hildenbrand1-20/+121
Commit e83a437faa62 ("mm/memory_hotplug: introduce "auto-movable" online policy") introduced a new memory online policy to automatically select a zone for memory blocks to be onlined. It added a way to set the active online policy and tunables for the auto-movable online policy. Follow-up commits tweaked the "auto-movable" policy to also consider memory device details when selecting zones for memory blocks to be onlined. Let's document the new toggles and how the two online policies we have work. [david@redhat.com: updates] Link: https://lkml.kernel.org/r/20211011082058.6076-4-david@redhat.com Link: https://lkml.kernel.org/r/20210930144117.23641-4-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Acked-by: Mike Rapoport <rppt@linux.ibm.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Michal Hocko <mhocko@suse.com> Cc: Oscar Salvador <osalvador@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-06memory-hotplug.rst: fix wrong /sys/module/memory_hotplug/parameters/ pathDavid Hildenbrand1-1/+1
We accidentially added a superfluous "s". Link: https://lkml.kernel.org/r/20210930144117.23641-3-david@redhat.com Fixes: ac3332c44767 ("memory-hotplug.rst: complete admin-guide overhaul") Signed-off-by: David Hildenbrand <david@redhat.com> Acked-by: Mike Rapoport <rppt@linux.ibm.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Michal Hocko <mhocko@suse.com> Cc: Oscar Salvador <osalvador@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-06memory-hotplug.rst: fix two instances of "movablecore" that should be ↵David Hildenbrand1-2/+2
"movable_node" Patch series "memory-hotplug.rst: document the "auto-movable" online policy". Now that the memory-hotplug.rst overhaul is upstream, proper documentation for the "auto-movable" online policy, documenting all new toggles and options. Along, two fixes for the original overhaul. This patch (of 3): We really want to refer to the "movable_node" kernel command line parameter here. Link: https://lkml.kernel.org/r/20210930144117.23641-2-david@redhat.com Fixes: ac3332c44767 ("memory-hotplug.rst: complete admin-guide overhaul") Signed-off-by: David Hildenbrand <david@redhat.com> Acked-by: Mike Rapoport <rppt@linux.ibm.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Michal Hocko <mhocko@suse.com> Cc: Oscar Salvador <osalvador@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-06hugetlbfs: extend the definition of hugepages parameter to support node ↵Zhenguo Yao2-4/+16
allocation We can specify the number of hugepages to allocate at boot. But the hugepages is balanced in all nodes at present. In some scenarios, we only need hugepages in one node. For example: DPDK needs hugepages which are in the same node as NIC. If DPDK needs four hugepages of 1G size in node1 and system has 16 numa nodes we must reserve 64 hugepages on the kernel cmdline. But only four hugepages are used. The others should be free after boot. If the system memory is low(for example: 64G), it will be an impossible task. So extend the hugepages parameter to support specifying hugepages on a specific node. For example add following parameter: hugepagesz=1G hugepages=0:1,1:3 It will allocate 1 hugepage in node0 and 3 hugepages in node1. Link: https://lkml.kernel.org/r/20211005054729.86457-1-yaozhenguo1@gmail.com Signed-off-by: Zhenguo Yao <yaozhenguo1@gmail.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: Zhenguo Yao <yaozhenguo1@gmail.com> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: Nathan Chancellor <nathan@kernel.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Mike Rapoport <rppt@kernel.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-06hugetlb: support node specified when using cma for gigantic hugepagesBaolin Wang1-2/+4
Now the size of CMA area for gigantic hugepages runtime allocation is balanced for all online nodes, but we also want to specify the size of CMA per-node, or only one node in some cases, which are similar with patch [1]. For example, on some multi-nodes systems, each node's memory can be different, allocating the same size of CMA for each node is not suitable for the low-memory nodes. Meanwhile some workloads like DPDK mentioned by Zhenguo in patch [1] only need hugepages in one node. On the other hand, we have some machines with multiple types of memory, like DRAM and PMEM (persistent memory). On this system, we may want to specify all the hugepages only on DRAM node, or specify the proportion of DRAM node and PMEM node, to tuning the performance of the workloads. Thus this patch adds node format for 'hugetlb_cma' parameter to support specifying the size of CMA per-node. An example is as follows: hugetlb_cma=0:5G,2:5G which means allocating 5G size of CMA area on node 0 and node 2 respectively. And the users should use the node specific sysfs file to allocate the gigantic hugepages if specified the CMA size on that node. Link: https://lkml.kernel.org/r/20211005054729.86457-1-yaozhenguo1@gmail.com [1] Link: https://lkml.kernel.org/r/bb790775ca60bb8f4b26956bb3f6988f74e075c7.1634261144.git.baolin.wang@linux.alibaba.com Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Roman Gushchin <guro@fb.com> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-06hugetlb: add demote hugetlb page sysfs interfacesMike Kravetz1-2/+28
Patch series "hugetlb: add demote/split page functionality", v4. The concurrent use of multiple hugetlb page sizes on a single system is becoming more common. One of the reasons is better TLB support for gigantic page sizes on x86 hardware. In addition, hugetlb pages are being used to back VMs in hosting environments. When using hugetlb pages to back VMs, it is often desirable to preallocate hugetlb pools. This avoids the delay and uncertainty of allocating hugetlb pages at VM startup. In addition, preallocating huge pages minimizes the issue of memory fragmentation that increases the longer the system is up and running. In such environments, a combination of larger and smaller hugetlb pages are preallocated in anticipation of backing VMs of various sizes. Over time, the preallocated pool of smaller hugetlb pages may become depleted while larger hugetlb pages still remain. In such situations, it is desirable to convert larger hugetlb pages to smaller hugetlb pages. Converting larger to smaller hugetlb pages can be accomplished today by first freeing the larger page to the buddy allocator and then allocating the smaller pages. For example, to convert 50 GB pages on x86: gb_pages=`cat .../hugepages-1048576kB/nr_hugepages` m2_pages=`cat .../hugepages-2048kB/nr_hugepages` echo $(($gb_pages - 50)) > .../hugepages-1048576kB/nr_hugepages echo $(($m2_pages + 25600)) > .../hugepages-2048kB/nr_hugepages On an idle system this operation is fairly reliable and results are as expected. The number of 2MB pages is increased as expected and the time of the operation is a second or two. However, when there is activity on the system the following issues arise: 1) This process can take quite some time, especially if allocation of the smaller pages is not immediate and requires migration/compaction. 2) There is no guarantee that the total size of smaller pages allocated will match the size of the larger page which was freed. This is because the area freed by the larger page could quickly be fragmented. In a test environment with a load that continually fills the page cache with clean pages, results such as the following can be observed: Unexpected number of 2MB pages allocated: Expected 25600, have 19944 real 0m42.092s user 0m0.008s sys 0m41.467s To address these issues, introduce the concept of hugetlb page demotion. Demotion provides a means of 'in place' splitting of a hugetlb page to pages of a smaller size. This avoids freeing pages to buddy and then trying to allocate from buddy. Page demotion is controlled via sysfs files that reside in the per-hugetlb page size and per node directories. - demote_size Target page size for demotion, a smaller huge page size. File can be written to chose a smaller huge page size if multiple are available. - demote Writable number of hugetlb pages to be demoted To demote 50 GB huge pages, one would: cat .../hugepages-1048576kB/free_hugepages /* optional, verify free pages */ cat .../hugepages-1048576kB/demote_size /* optional, verify target size */ echo 50 > .../hugepages-1048576kB/demote Only hugetlb pages which are free at the time of the request can be demoted. Demotion does not add to the complexity of surplus pages and honors reserved huge pages. Therefore, when a value is written to the sysfs demote file, that value is only the maximum number of pages which will be demoted. It is possible fewer will actually be demoted. The recently introduced per-hstate mutex is used to synchronize demote operations with other operations that modify hugetlb pools. Real world use cases -------------------- The above scenario describes a real world use case where hugetlb pages are used to back VMs on x86. Both issues of long allocation times and not necessarily getting the expected number of smaller huge pages after a free and allocate cycle have been experienced. The occurrence of these issues is dependent on other activity within the host and can not be predicted. This patch (of 5): Two new sysfs files are added to demote hugtlb pages. These files are both per-hugetlb page size and per node. Files are: demote_size - The size in Kb that pages are demoted to. (read-write) demote - The number of huge pages to demote. (write-only) By default, demote_size is the next smallest huge page size. Valid huge page sizes less than huge page size may be written to this file. When huge pages are demoted, they are demoted to this size. Writing a value to demote will result in an attempt to demote that number of hugetlb pages to an appropriate number of demote_size pages. NOTE: Demote interfaces are only provided for huge page sizes if there is a smaller target demote huge page size. For example, on x86 1GB huge pages will have demote interfaces. 2MB huge pages will not have demote interfaces. This patch does not provide full demote functionality. It only provides the sysfs interfaces. It also provides documentation for the new interfaces. [mike.kravetz@oracle.com: n_mask initialization does not need to be protected by the mutex] Link: https://lkml.kernel.org/r/0530e4ef-2492-5186-f919-5db68edea654@oracle.com Link: https://lkml.kernel.org/r/20211007181918.136982-2-mike.kravetz@oracle.com Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Cc: David Hildenbrand <david@redhat.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Zi Yan <ziy@nvidia.com> Cc: Muchun Song <songmuchun@bytedance.com> Cc: Naoya Horiguchi <naoya.horiguchi@linux.dev> Cc: David Rientjes <rientjes@google.com> Cc: "Aneesh Kumar K . V" <aneesh.kumar@linux.ibm.com> Cc: Nghia Le <nghialm78@gmail.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-06Documentation: update pagemap with shmem exceptionsTiberiu A Georgescu1-0/+22
This patch follows the discussions on previous documentation patch threads [1][2]. It presents the exception case of shared memory management from the pagemap's point of view. It briefly describes what is missing, why it is missing and alternatives to the pagemap for page info retrieval in user space. In short, the kernel does not keep track of PTEs for swapped out shared pages within the processes that references them. Thus, the proc/pid/pagemap tool cannot print the swap destination of the shared memory pages, instead setting the pagemap entry to zero for both non-allocated and swapped out pages. This can create confusion for users who need information on swapped out pages. The reasons why maintaining the PTEs of all swapped out shared pages among all processes while maintaining similar performance is not a trivial task, or a desirable change, have been discussed extensively [1][3][4][5]. There are also arguments for why this arguably missing information should eventually be exposed to the user in either a future pagemap patch, or by an alternative tool. [1]: https://marc.info/?m=162878395426774 [2]: https://lore.kernel.org/lkml/20210920164931.175411-1-tiberiu.georgescu@nutanix.com/ [3]: https://lore.kernel.org/lkml/20210730160826.63785-1-tiberiu.georgescu@nutanix.com/ [4]: https://lore.kernel.org/lkml/20210807032521.7591-1-peterx@redhat.com/ [5]: https://lore.kernel.org/lkml/20210715201651.212134-1-peterx@redhat.com/ Mention the current missing information in the pagemap and alternatives on how to retrieve it, in case someone stumbles upon unexpected behaviour. Link: https://lkml.kernel.org/r/20210923064618.157046-1-tiberiu.georgescu@nutanix.com Link: https://lkml.kernel.org/r/20210923064618.157046-2-tiberiu.georgescu@nutanix.com Signed-off-by: Tiberiu A Georgescu <tiberiu.georgescu@nutanix.com> Reviewed-by: Ivan Teterevkov <ivan.teterevkov@nutanix.com> Reviewed-by: Florian Schmidt <florian.schmidt@nutanix.com> Reviewed-by: Carl Waldspurger <carl.waldspurger@nutanix.com> Reviewed-by: Jonathan Davies <jonathan.davies@nutanix.com> Reviewed-by: Peter Xu <peterx@redhat.com> Reviewed-by: David Hildenbrand <david@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-06memcg, kmem: further deprecate kmem.limit_in_bytesShakeel Butt1-9/+2
The deprecation process of kmem.limit_in_bytes started with the commit 0158115f702 ("memcg, kmem: deprecate kmem.limit_in_bytes") which also explains in detail the motivation behind the deprecation. To summarize, it is the unexpected behavior on hitting the kmem limit. This patch moves the deprecation process to the next stage by disallowing to set the kmem limit. In future we might just remove the kmem.limit_in_bytes file completely. [akpm@linux-foundation.org: s/ENOTSUPP/EOPNOTSUPP/] [arnd@arndb.de: mark cancel_charge() inline] Link: https://lkml.kernel.org/r/20211022070542.679839-1-arnd@kernel.org Link: https://lkml.kernel.org/r/20211019153408.2916808-1-shakeelb@google.com Signed-off-by: Shakeel Butt <shakeelb@google.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Roman Gushchin <guro@fb.com> Acked-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Muchun Song <songmuchun@bytedance.com> Cc: Vasily Averin <vvs@virtuozzo.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-04xen/balloon: add late_initcall_sync() for initial ballooning doneJuergen Gross1-0/+7
When running as PVH or HVM guest with actual memory < max memory the hypervisor is using "populate on demand" in order to allow the guest to balloon down from its maximum memory size. For this to work correctly the guest must not touch more memory pages than its target memory size as otherwise the PoD cache will be exhausted and the guest is crashed as a result of that. In extreme cases ballooning down might not be finished today before the init process is started, which can consume lots of memory. In order to avoid random boot crashes in such cases, add a late init call to wait for ballooning down having finished for PVH/HVM guests. Warn on console if initial ballooning fails, panic() after stalling for more than 3 minutes per default. Add a module parameter for changing this timeout. [boris: replaced pr_info() with pr_notice()] Cc: <stable@vger.kernel.org> Reported-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com> Signed-off-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/20211102091944.17487-1-jgross@suse.com Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2021-11-04Merge tag 'driver-core-5.16-rc1' of ↵Linus Torvalds2-12/+8
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core updates from Greg KH: "Here is the big set of driver core changes for 5.16-rc1. All of these have been in linux-next for a while now with no reported problems. Included in here are: - big update and cleanup of the sysfs abi documentation files and scripts from Mauro. We are almost at the place where we can properly check that the running kernel's sysfs abi is documented fully. - firmware loader updates - dyndbg updates - kernfs cleanups and fixes from Christoph - device property updates - component fix - other minor driver core cleanups and fixes" * tag 'driver-core-5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (122 commits) device property: Drop redundant NULL checks x86/build: Tuck away built-in firmware under FW_LOADER vmlinux.lds.h: wrap built-in firmware support under FW_LOADER firmware_loader: move struct builtin_fw to the only place used x86/microcode: Use the firmware_loader built-in API firmware_loader: remove old DECLARE_BUILTIN_FIRMWARE() firmware_loader: formalize built-in firmware API component: do not leave master devres group open after bind dyndbg: refine verbosity 1-4 summary-detail gpiolib: acpi: Replace custom code with device_match_acpi_handle() i2c: acpi: Replace custom function with device_match_acpi_handle() driver core: Provide device_match_acpi_handle() helper dyndbg: fix spurious vNpr_info change dyndbg: no vpr-info on empty queries