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2021-11-01nfsd: document server-to-server-copy parametersJ. Bruce Fields
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2021-11-01speakup: Fix typo in documentation "boo" -> "boot"Colin Ian King
There is a typo in the speakup documentation. Fix it. Signed-off-by: Colin Ian King <colin.i.king@gmail.com> Reviewed-by: Samuel Thibault <samuel.thibault@ens-lyon.org> Link: https://lore.kernel.org/r/20211028182319.613315-1-colin.i.king@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-11-01docs: Fix formatting of literal sections in fanotify docsGabriel Krisman Bertazi
Stephen Rothwell reported the following warning was introduced by commit c0baf9ac0b05 ("docs: Document the FAN_FS_ERROR event"). Documentation/admin-guide/filesystem-monitoring.rst:60: WARNING: Definition list ends without a blank line; unexpected unindent. Link: https://lore.kernel.org/r/87y26camhe.fsf@collabora.com Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com> Signed-off-by: Jan Kara <jack@suse.cz>
2021-10-31Merge tag 'kvmarm-5.16' of ↵Paolo Bonzini
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 updates for Linux 5.16 - More progress on the protected VM front, now with the full fixed feature set as well as the limitation of some hypercalls after initialisation. - Cleanup of the RAZ/WI sysreg handling, which was pointlessly complicated - Fixes for the vgic placement in the IPA space, together with a bunch of selftests - More memcg accounting of the memory allocated on behalf of a guest - Timer and vgic selftests - Workarounds for the Apple M1 broken vgic implementation - KConfig cleanups - New kvmarm.mode=none option, for those who really dislike us
2021-10-27docs: Document the FAN_FS_ERROR eventGabriel Krisman Bertazi
Document the FAN_FS_ERROR event for user administrators and user space developers. Link: https://lore.kernel.org/r/20211025192746.66445-32-krisman@collabora.com Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Jan Kara <jack@suse.cz>
2021-10-26s390/pci: add s390_iommu_aperture kernel parameterNiklas Schnelle
Some applications map the same memory area for DMA multiple times while also mapping significant amounts of memory. With our current DMA code these applications will run out of DMA addresses after mapping half of the available memory because the number of DMA mappings is constrained by the number of concurrently active DMA addresses we support which in turn is limited by the minimum of hardware constraints and high_memory. Limiting the number of active DMA addresses to high_memory is only a heuristic to save memory used by the iommu_bitmap and DMA page tables however. This was added under the assumption that it rarely makes sense to DMA map more than system memory. To accommodate special applications which insist on double mapping, which works on other platforms, allow specifying a factor of how many times installed memory is available as DMA address space. Use 0 as a special value to apply no constraints beyond what hardware dictates at the expense of significantly more memory use. Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com> Reviewed-by: Pierre Morel <pmorel@linux.ibm.com> Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-10-26x86/signal: Implement sigaltstack size validationThomas Gleixner
For historical reasons MINSIGSTKSZ is a constant which became already too small with AVX512 support. Add a mechanism to enforce strict checking of the sigaltstack size against the real size of the FPU frame. The strict check can be enabled via a config option and can also be controlled via the kernel command line option 'strict_sas_size' independent of the config switch. Enabling it might break existing applications which allocate a too small sigaltstack but 'work' because they never get a signal delivered. Though it can be handy to filter out binaries which are not yet aware of AT_MINSIGSTKSZ. Also the upcoming support for dynamically enabled FPU features requires a strict sanity check to ensure that: - Enabling of a dynamic feature, which changes the sigframe size fits into an enabled sigaltstack - Installing a too small sigaltstack after a dynamic feature has been added is not possible. Implement the base check which is controlled by config and command line options. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20211021225527.10184-3-chang.seok.bae@intel.com
2021-10-22kvm: x86: mmu: Make NX huge page recovery period configurableJunaid Shahid
Currently, the NX huge page recovery thread wakes up every minute and zaps 1/nx_huge_pages_recovery_ratio of the total number of split NX huge pages at a time. This is intended to ensure that only a relatively small number of pages get zapped at a time. But for very large VMs (or more specifically, VMs with a large number of executable pages), a period of 1 minute could still result in this number being too high (unless the ratio is changed significantly, but that can result in split pages lingering on for too long). This change makes the period configurable instead of fixing it at 1 minute. Users of large VMs can then adjust the period and/or the ratio to reduce the number of pages zapped at one time while still maintaining the same overall duration for cycling through the entire list. By default, KVM derives a period from the ratio such that a page will remain on the list for 1 hour on average. Signed-off-by: Junaid Shahid <junaids@google.com> Message-Id: <20211020010627.305925-1-junaids@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-21dyndbg: refine verbosity 1-4 summary-detailJim Cromie
adjust current v*pr_info() calls to fit an overview..detail scheme: 1- module level activity: add/remove, etc 2- command ingest, splitting, summary of effects. per >control write 3- command parsing: op, flags, search terms 4- per-site change msg can yield ~3k x 2 logs per echo "+p;-p" > command. Summarize these 4 levels in MODULE_PARM_DESC, and update verbose=3 in Doc. 2- is new, to isolate a problem where a stress-test script (which feeds ~4kb multi-command strings) would produce short writes, truncating last command and causing parsing errors, which confused test results. The script fix was to use syswrite, to deliver full proper commands. 4- gets per-callsite "changed:" pr-infos, which are very noisy during stress tests, and formerly obscured v1-3 messages, and overwhelmed the static-key workload being tested. The verbose parameter has previously seen adjustment: commit 481c0e33f1e7 ("dyndbg: refine debug verbosity; 1 is basic, 2 more chatty") The script driving these adjustments is: !/usr/bin/perl -w =for Doc 1st purpose was to benchmark the effect of wildcard queries on query performance; if wildcards are risk free cheap enough, we can deploy them in the (floating) format search. 1st finding: wildcards take 2x as long to process. 2nd purpose was to benchmark real static-key changes VS simple flag changes. Found ~100x decrease for the hard work. The script maximizes workload per >control by packing it a ~4kb string of "+p; -p;" commands; this uncovered some broken stuff. The 85th query failed, and appears to be truncated, so is gramatically incorrect. Its either an error here, or in the kernel. Its not happening atm, retest. Plot thickens: fail only happens doing +-p, not +-mf, likely load dependent. Error remains consistent. Looks like a short write, longer on writer than kernel-reader. Try syswrite on handle to control this. That fixed short write. =cut use Getopt::Std; getopts('vN:k:', \my %opts) or die <<EOH; $0 options: -v verbose -k=n kernel dyndbg verbosity -N=n number of loops.. tbrc EOH $opts{N} //= 10; # !undef, 0 tests too long. my $ctrl = '/proc/dynamic_debug/control'; vx($opts{k}) if defined $opts{k}; # works on -k0 open(my $CTL, '>', $ctrl) or die "cant open $ctrl for writing: $!\n"; sub vx { my $arg = shift; my $cmd = "echo $arg > /sys/module/dynamic_debug/parameters/verbose"; system($cmd); warn("vx problem: rc:$? err:$! qry: $cmd\n") if ($?); } sub qryOK { my $qry = shift; print "syntax test: <\n$qry>\n" if $opts{v}; my $bytes = syswrite $CTL, $qry; printf "short read: $bytes / %d\n", length $qry if $bytes < length $qry; if ($?) { warn "rc:$? err:$! qry: $qry\n"; return 0; } return 1; } sub build_queries { my ($cmd, $flags, $ct) = @_; # build experiment and reference queries my $cycle = " $cmd +$flags # on ; $cmd -$flags # off \n"; my $ref = " +$flags ; -$flags \n"; my $len = length $cycle; my $max = int(4096 / $len); # break/fit to buffer size $ct |= $max; print "qry: ct:$max x << \n$cycle >>\n"; return unless qryOK($ref); return unless qryOK($cycle); my $wild = $cycle x $ct; my $empty = $ref x $ct; printf "len: %d, %d\n", length $wild, length $empty; return { trial => $wild, ref => $empty, probe => $cycle, zero => $ref, count => $ct, max => $max }; } my $query_set = build_queries(' file "*" module "*" func "*" ', "mf"); qryOK($query_set->{zero}); qryOK($query_set->{probe}); qryOK($query_set->{ref}); qryOK($query_set->{trial}); use Benchmark; sub dobatch { my ($cmd, $flags, $reps, $ct) = @_; $reps ||= $opts{N}; my $qs = build_queries($cmd, $flags, $ct); timethese($reps, { wildcards => sub { syswrite $CTL, $qs->{trial}; }, no_search => sub { syswrite $CTL, $qs->{ref}; } } ); } sub bench_static_key_toggle { vx 0; dobatch(' file "*" module "*" func "*" ', "mf"); dobatch(' file "*" module "*" func "*" ', "p"); } sub bench_verbose_levels { for my $i (0..4) { vx $i; dobatch(' file "*" module "*" func "*" ', "mf"); } } bench_static_key_toggle(); __END__ Heres how the test-script runs: :: verbose=3 parsing info [ 48.401646] dyndbg: query 95: "file "*" module "*" func "*" -mf # off " mod:* [ 48.402040] dyndbg: split into words: "file" "*" "module" "*" "func" "*" "-mf" [ 48.402456] dyndbg: op='-' [ 48.402615] dyndbg: flags=0x6 [ 48.402779] dyndbg: *flagsp=0x0 *maskp=0xfffffff9 [ 48.403033] dyndbg: parsed: func="*" file="*" module="*" format="" lineno=0-0 [ 48.403674] dyndbg: applied: func="*" file="*" module="*" format="" lineno=0-0 :: verbose=2 >control summary. ~300k site matches/changes per 4kb command [ 48.404063] dyndbg: processed 96 queries, with 296160 matches, 0 errs :: 2 queries against each other, no-search vs all-wildcard-search qry: ct:48 x << file "*" module "*" func "*" +mf # on ; file "*" module "*" func "*" -mf # off >> len: 4080, 576 Benchmark: timing 10 iterations of no_search, wildcards... no_search: 0 wallclock secs ( 0.00 usr + 0.03 sys = 0.03 CPU) @ 333.33/s (n=10) (warning: too few iterations for a reliable count) wildcards: 0 wallclock secs ( 0.00 usr + 0.09 sys = 0.09 CPU) @ 111.11/s (n=10) (warning: too few iterations for a reliable count) :: 2 queries, both doing real work / changing stati-key states. qry: ct:49 x << file "*" module "*" func "*" +p # on ; file "*" module "*" func "*" -p # off >> len: 4067, 490 Benchmark: timing 10 iterations of no_search, wildcards... no_search: 20 wallclock secs ( 0.00 usr + 20.36 sys = 20.36 CPU) @ 0.49/s (n=10) wildcards: 21 wallclock secs ( 0.00 usr + 21.08 sys = 21.08 CPU) @ 0.47/s (n=10) bash-5.1# Thats 150k static-key-toggles / sec ~600x slower than simple flags on qemu --smp 3 run Signed-off-by: Jim Cromie <jim.cromie@gmail.com> Link: https://lore.kernel.org/r/20211019210746.185307-1-jim.cromie@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-19dt-bindings: reserved-memory: ramoops: update ramoops.yaml referencesMauro Carvalho Chehab
Changeset 89a5bf0f22fd ("dt-bindings: reserved-memory: ramoops: Convert txt bindings to yaml") renamed: Documentation/devicetree/bindings/reserved-memory/ramoops.txt to: Documentation/devicetree/bindings/reserved-memory/ramoops.yaml. Update the cross-references accordingly. Fixes: 89a5bf0f22fd ("dt-bindings: reserved-memory: ramoops: Convert txt bindings to yaml") Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Reviewed-by: David Heidelberg <david@ixit.cz> Signed-off-by: Rob Herring <robh@kernel.org> Link: https://lore.kernel.org/r/bccd9c181b68a1ebbaefd5dcce63e1b8a4b1596c.1634630486.git.mchehab+huawei@kernel.org
2021-10-18Merge 5.15-rc6 into driver-core-nextGreg Kroah-Hartman
We need the driver-core fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-15topology: Represent clusters of CPUs within a dieJonathan Cameron
Both ACPI and DT provide the ability to describe additional layers of topology between that of individual cores and higher level constructs such as the level at which the last level cache is shared. In ACPI this can be represented in PPTT as a Processor Hierarchy Node Structure [1] that is the parent of the CPU cores and in turn has a parent Processor Hierarchy Nodes Structure representing a higher level of topology. For example Kunpeng 920 has 6 or 8 clusters in each NUMA node, and each cluster has 4 cpus. All clusters share L3 cache data, but each cluster has local L3 tag. On the other hand, each clusters will share some internal system bus. +-----------------------------------+ +---------+ | +------+ +------+ +--------------------------+ | | | CPU0 | | cpu1 | | +-----------+ | | | +------+ +------+ | | | | | | +----+ L3 | | | | +------+ +------+ cluster | | tag | | | | | CPU2 | | CPU3 | | | | | | | +------+ +------+ | +-----------+ | | | | | | +-----------------------------------+ | | +-----------------------------------+ | | | +------+ +------+ +--------------------------+ | | | | | | | +-----------+ | | | +------+ +------+ | | | | | | | | L3 | | | | +------+ +------+ +----+ tag | | | | | | | | | | | | | | +------+ +------+ | +-----------+ | | | | | | +-----------------------------------+ | L3 | | data | +-----------------------------------+ | | | +------+ +------+ | +-----------+ | | | | | | | | | | | | | +------+ +------+ +----+ L3 | | | | | | tag | | | | +------+ +------+ | | | | | | | | | | | +-----------+ | | | +------+ +------+ +--------------------------+ | +-----------------------------------| | | +-----------------------------------| | | | +------+ +------+ +--------------------------+ | | | | | | | +-----------+ | | | +------+ +------+ | | | | | | +----+ L3 | | | | +------+ +------+ | | tag | | | | | | | | | | | | | | +------+ +------+ | +-----------+ | | | | | | +-----------------------------------+ | | +-----------------------------------+ | | | +------+ +------+ +--------------------------+ | | | | | | | +-----------+ | | | +------+ +------+ | | | | | | | | L3 | | | | +------+ +------+ +---+ tag | | | | | | | | | | | | | | +------+ +------+ | +-----------+ | | | | | | +-----------------------------------+ | | +-----------------------------------+ | | | +------+ +------+ +--------------------------+ | | | | | | | +-----------+ | | | +------+ +------+ | | | | | | | | L3 | | | | +------+ +------+ +--+ tag | | | | | | | | | | | | | | +------+ +------+ | +-----------+ | | | | +---------+ +-----------------------------------+ That means spreading tasks among clusters will bring more bandwidth while packing tasks within one cluster will lead to smaller cache synchronization latency. So both kernel and userspace will have a chance to leverage this topology to deploy tasks accordingly to achieve either smaller cache latency within one cluster or an even distribution of load among clusters for higher throughput. This patch exposes cluster topology to both kernel and userspace. Libraried like hwloc will know cluster by cluster_cpus and related sysfs attributes. PoC of HWLOC support at [2]. Note this patch only handle the ACPI case. Special consideration is needed for SMT processors, where it is necessary to move 2 levels up the hierarchy from the leaf nodes (thus skipping the processor core level). Note that arm64 / ACPI does not provide any means of identifying a die level in the topology but that may be unrelate to the cluster level. [1] ACPI Specification 6.3 - section 5.2.29.1 processor hierarchy node structure (Type 0) [2] https://github.com/hisilicon/hwloc/tree/linux-cluster Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Tian Tao <tiantao6@hisilicon.com> Signed-off-by: Barry Song <song.bao.hua@hisilicon.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20210924085104.44806-2-21cnbao@gmail.com
2021-10-14Documentation: dyndbg: Improve cli param examplesAndrew Halaney
Jim pointed out that using $module.dyndbg= is always a more flexible choice for using dynamic debug on the command line. The $module.dyndbg style is checked at boot and handles if $module is a builtin. If it is actually a loadable module, it is handled again later when the module is loaded. If you just use dyndbg="module $module +p" dynamic debug is only enabled when $module is a builtin. It was recommended to illustrate wildcard usage as well. Suggested-by: Jim Cromie <jim.cromie@gmail.com> Signed-off-by: Andrew Halaney <ahalaney@redhat.com> Signed-off-by: Jason Baron <jbaron@akamai.com> Link: https://lore.kernel.org/r/1634139622-20667-4-git-send-email-jbaron@akamai.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-14dyndbg: Remove support for ddebug_query paramAndrew Halaney
This param has been deprecated for a very long time now, let's rip it out. Signed-off-by: Andrew Halaney <ahalaney@redhat.com> Signed-off-by: Jason Baron <jbaron@akamai.com> Link: https://lore.kernel.org/r/1634139622-20667-3-git-send-email-jbaron@akamai.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-11Merge branch 'for-5.15-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup Pull cgroup fixes from Tejun Heo: "All documentation / comment updates" * 'for-5.15-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: cgroupv2, docs: fix misinformation in "device controller" section cgroup/cpuset: Change references of cpuset_mutex to cpuset_rwsem docs/cgroup: remove some duplicate words
2021-10-11Merge branch kvm-arm64/pkvm/restrict-hypercalls into kvmarm-master/nextMarc Zyngier
* kvm-arm64/pkvm/restrict-hypercalls: : . : Restrict the use of some hypercalls as well as kexec once : the protected KVM mode has been initialised. : . Documentation: admin-guide: Document side effects when pKVM is enabled Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-10-11Documentation: admin-guide: Document side effects when pKVM is enabledAlexandru Elisei
Recent changes to KVM for arm64 has made it impossible for the host to hibernate or use kexec when protected mode is enabled via the kernel command line. There are people who rely on kexec (for example, developers who use kexec as a quick way to test a new kernel), let's document this change in behaviour, so it doesn't catch them by surprise and we have a place to point people to if it does. Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20211011153835.291147-1-alexandru.elisei@arm.com
2021-10-11KVM: arm64: Allow KVM to be disabled from the command lineMarc Zyngier
Although KVM can be compiled out of the kernel, it cannot be disabled at runtime. Allow this possibility by introducing a new mode that will prevent KVM from initialising. This is useful in the (limited) circumstances where you don't want KVM to be available (what is wrong with you?), or when you want to install another hypervisor instead (good luck with that). Reviewed-by: David Brazdil <dbrazdil@google.com> Acked-by: Will Deacon <will@kernel.org> Acked-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Andrew Scull <ascull@google.com> Link: https://lore.kernel.org/r/20211001170553.3062988-1-maz@kernel.org
2021-10-08Merge tag 'for-linus-5.15b-rc5-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen fixes from Juergen Gross: - fix two minor issues in the Xen privcmd driver plus a cleanup patch for that driver - fix multiple issues related to running as PVH guest and some related earlyprintk fixes for other Xen guest types - fix an issue introduced in 5.15 the Xen balloon driver * tag 'for-linus-5.15b-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen/balloon: fix cancelled balloon action xen/x86: adjust data placement x86/PVH: adjust function/data placement xen/x86: hook up xen_banner() also for PVH xen/x86: generalize preferred console model from PV to PVH Dom0 xen/x86: make "earlyprintk=xen" work for HVM/PVH DomU xen/x86: allow "earlyprintk=xen" to work for PV Dom0 xen/x86: make "earlyprintk=xen" work better for PVH Dom0 xen/x86: allow PVH Dom0 without XEN_PV=y xen/x86: prevent PVH type from getting clobbered xen/privcmd: drop "pages" parameter from xen_remap_pfn() xen/privcmd: fix error handling in mmap-resource processing xen/privcmd: replace kcalloc() by kvcalloc() when allocating empty pages
2021-10-08media: admin-guide: Update i2c-cardlistSakari Ailus
Add MIPI CCS compliant devices, a few Sony IMX, Hynix Hi-846 and Omnivision ov13b10 sensors and the DW9768 lens driver to the list of supported devices. Also drop SMIA since as a standard it is obsolete. Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2021-10-08media: Documentation: i2c-cardlist: add the Hynix hi846 sensorMartin Kepplinger
Add the SK Hynix Hi-846 8M Pixel CMOS image sensor to the i2c-cardlist. Signed-off-by: Martin Kepplinger <martin.kepplinger@puri.sm> Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2021-10-05sched/fair: Add document for burstable CFS bandwidthHuaixin Chang
Basic description of usage and effect for CFS Bandwidth Control Burst. Co-developed-by: Shanpei Chen <shanpeic@linux.alibaba.com> Signed-off-by: Shanpei Chen <shanpeic@linux.alibaba.com> Co-developed-by: Tianchen Ding <dtcccc@linux.alibaba.com> Signed-off-by: Tianchen Ding <dtcccc@linux.alibaba.com> Signed-off-by: Huaixin Chang <changhuaixin@linux.alibaba.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20210830032215.16302-3-changhuaixin@linux.alibaba.com
2021-10-05xen/x86: make "earlyprintk=xen" work for HVM/PVH DomUJan Beulich
xenboot_write_console() is dealing with these quite fine so I don't see why xenboot_console_setup() would return -ENOENT in this case. Adjust documentation accordingly. Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/3d212583-700e-8b2d-727a-845ef33ac265@suse.com Signed-off-by: Juergen Gross <jgross@suse.com>
2021-10-04Merge tag 'v5.15-rc4' into docs-nextJonathan Corbet
This is needed to get a docs fix that entered via the DRM tree; testers have requested it so that PDF builds in docs-next work again.
2021-10-04x86: deduplicate the spectre_v2_user documentationAndrea Arcangeli
This would need updating to make prctl be the new default, but it's simpler to delete it and refer to the dup. Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20201105001406.13005-2-aarcange@redhat.com
2021-10-04x86: change default to spec_store_bypass_disable=prctl spectre_v2_user=prctlAndrea Arcangeli
Switch the kernel default of SSBD and STIBP to the ones with CONFIG_SECCOMP=n (i.e. spec_store_bypass_disable=prctl spectre_v2_user=prctl) even if CONFIG_SECCOMP=y. Several motivations listed below: - If SMT is enabled the seccomp jail can still attack the rest of the system even with spectre_v2_user=seccomp by using MDS-HT (except on XEON PHI where MDS can be tamed with SMT left enabled, but that's a special case). Setting STIBP become a very expensive window dressing after MDS-HT was discovered. - The seccomp jail cannot attack the kernel with spectre-v2-HT regardless (even if STIBP is not set), but with MDS-HT the seccomp jail can attack the kernel too. - With spec_store_bypass_disable=prctl the seccomp jail can attack the other userland (guest or host mode) using spectre-v2-HT, but the userland attack is already mitigated by both ASLR and pid namespaces for host userland and through virt isolation with libkrun or kata. (if something if somebody is worried about spectre-v2-HT it's best to mount proc with hidepid=2,gid=proc on workstations where not all apps may run under container runtimes, rather than slowing down all seccomp jails, but the best is to add pid namespaces to the seccomp jail). As opposed MDS-HT is not mitigated and the seccomp jail can still attack all other host and guest userland if SMT is enabled even with spec_store_bypass_disable=seccomp. - If full security is required then MDS-HT must also be mitigated with nosmt and then spectre_v2_user=prctl and spectre_v2_user=seccomp would become identical. - Setting spectre_v2_user=seccomp is overall lower priority than to setting javascript.options.wasm false in about:config to protect against remote wasm MDS-HT, instead of worrying about Spectre-v2-HT and STIBP which again is already statistically well mitigated by other means in userland and it's fully mitigated in kernel with retpolines (unlike the wasm assist call with MDS-HT). - SSBD is needed to prevent reading the JIT memory and the primary user being the OpenJDK. However the primary user of SSBD wouldn't be covered by spec_store_bypass_disable=seccomp because it doesn't use seccomp and the primary user also explicitly declined to set PR_SET_SPECULATION_CTRL+PR_SPEC_STORE_BYPASS despite it easily could. In fact it would need to set it only when the sandboxing mechanism is enabled for javaws applets, but it still declined it by declaring security within the same user address space as an untenable objective for their JIT, even in the sandboxing case where performance would be a lesser concern (for the record: I kind of disagree in not setting PR_SPEC_STORE_BYPASS in the sandbox case and I prefer to run javaws through a wrapper that sets PR_SPEC_STORE_BYPASS if I need). In turn it can be inferred that even if the primary user of SSBD would use seccomp, they would invoke it with SECCOMP_FILTER_FLAG_SPEC_ALLOW by now. - runc/crun already set SECCOMP_FILTER_FLAG_SPEC_ALLOW by default, k8s and podman have a default json seccomp allowlist that cannot be slowed down, so for the #1 seccomp user this change is already a noop. - systemd/sshd or other apps that use seccomp, if they really need STIBP or SSBD, they need to explicitly set the PR_SET_SPECULATION_CTRL by now. The stibp/ssbd seccomp blind catch-all approach was done probably initially with a wishful thinking objective to pretend to have a peace of mind that it could magically fix it all. That was wishful thinking before MDS-HT was discovered, but after MDS-HT has been discovered it become just window dressing. - For qemu "-sandbox" seccomp jail it wouldn't make sense to set STIBP or SSBD. SSBD doesn't help with KVM because there's no JIT (if it's needed with TCG it should be an opt-in with PR_SET_SPECULATION_CTRL+PR_SPEC_STORE_BYPASS and it shouldn't slowdown KVM for nothing). For qemu+KVM STIBP would be even more window dressing than it is for all other apps, because in the qemu+KVM case there's not only the MDS attack to worry about with SMT enabled. Even after disabling SMT, there's still a theoretical spectre-v2 attack possible within the same thread context from guest mode to host ring3 that the host kernel retpoline mitigation has no theoretical chance to mitigate. On some kernels a ibrs-always/ibrs-retpoline opt-in model is provided that will enabled IBRS in the qemu host ring3 userland which fixes this theoretical concern. Only after enabling IBRS in the host userland it would then make sense to proceed and worry about STIBP and an attack on the other host userland, but then again SMT would need to be disabled for full security anyway, so that would render STIBP again a noop. - last but not the least: the lack of "spec_store_bypass_disable=prctl spectre_v2_user=prctl" means the moment a guest boots and sshd/systemd runs, the guest kernel will write to SPEC_CTRL MSR which will make the guest vmexit forever slower, forcing KVM to issue a very slow rdmsr instruction at every vmexit. So the end result is that SPEC_CTRL MSR is only available in GCE. Most other public cloud providers don't expose SPEC_CTRL, which means that not only STIBP/SSBD isn't available, but IBPB isn't available either (which would cause no overhead to the guest or the hypervisor because it's write only and requires no reading during vmexit). So the current default already net loss in security (missing IBPB) which means most public cloud providers cannot achieve a fully secure guest with nosmt (and nosmt is enough to fully mitigate MDS-HT). It also means GCE and is unfairly penalized in performance because it provides the option to enable full security in the guest as an opt-in (i.e. nosmt and IBPB). So this change will allow all cloud providers to expose SPEC_CTRL without incurring into any hypervisor slowdown and at the same time it will remove the unfair penalization of GCE performance for doing the right thing and it'll allow to get full security with nosmt with IBPB being available (and STIBP becoming meaningless). Example to put things in prospective: the STIBP enabled in seccomp has never been about protecting apps using seccomp like sshd from an attack from a malicious userland, but to the contrary it has always been about protecting the system from an attack from sshd, after a successful remote network exploit against sshd. In fact initially it wasn't obvious STIBP would work both ways (STIBP was about preventing the task that runs with STIBP to be attacked with spectre-v2-HT, but accidentally in the STIBP case it also prevents the attack in the other direction). In the hypothetical case that sshd has been remotely exploited the last concern should be STIBP being set, because it'll be still possible to obtain info even from the kernel by using MDS if nosmt wasn't set (and if it was set, STIBP is a noop in the first place). As opposed kernel cannot leak anything with spectre-v2 HT because of retpolines and the userland is mitigated by ASLR already and ideally PID namespaces too. If something it'd be worth checking if sshd run the seccomp thread under pid namespaces too if available in the running kernel. SSBD also would be a noop for sshd, since sshd uses no JIT. If sshd prefers to keep doing the STIBP window dressing exercise, it still can even after this change of defaults by opting-in with PR_SPEC_INDIRECT_BRANCH. Ultimately setting SSBD and STIBP by default for all seccomp jails is a bad sweet spot and bad default with more cons than pros that end up reducing security in the public cloud (by giving an huge incentive to not expose SPEC_CTRL which would be needed to get full security with IBPB after setting nosmt in the guest) and by excessively hurting performance to more secure apps using seccomp that end up having to opt out with SECCOMP_FILTER_FLAG_SPEC_ALLOW. The following is the verified result of the new default with SMT enabled: (gdb) print spectre_v2_user_stibp $1 = SPECTRE_V2_USER_PRCTL (gdb) print spectre_v2_user_ibpb $2 = SPECTRE_V2_USER_PRCTL (gdb) print ssb_mode $3 = SPEC_STORE_BYPASS_PRCTL Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20201104235054.5678-1-aarcange@redhat.com Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Link: https://lore.kernel.org/lkml/AAA2EF2C-293D-4D5B-BFA6-FF655105CD84@redhat.com Acked-by: Waiman Long <longman@redhat.com> Link: https://lore.kernel.org/lkml/c0722838-06f7-da6b-138f-e0f26362f16a@redhat.com
2021-09-30media: vimc: Enable set resolution at the scaler src padPedro Terra
Modify the scaler subdevice to accept setting the resolution of the source pad (previously the source resolution would always be 3 times the sink for both dimensions). Now any resolution can be set at src (even smaller ones) and the sink video will be scaled to match it. Test example: With the vimc module up (using the default vimc topology) media-ctl -d platform:vimc -V '"Sensor A":0[fmt:SBGGR8_1X8/640x480]' media-ctl -d platform:vimc -V '"Debayer A":0[fmt:SBGGR8_1X8/640x480]' media-ctl -d platform:vimc -V '"Scaler":0[fmt:RGB888_1X24/640x480]' media-ctl -d platform:vimc -V '"Scaler":0[crop:(100,50)/400x150]' media-ctl -d platform:vimc -V '"Scaler":1[fmt:RGB888_1X24/300x700]' v4l2-ctl -z platform:vimc -d "RGB/YUV Capture" -v width=300,height=700 v4l2-ctl -z platform:vimc -d "Raw Capture 0" -v pixelformat=BA81 v4l2-ctl --stream-mmap --stream-count=10 -z platform:vimc -d "RGB/YUV Capture" \ --stream-to=test.raw The result will be a cropped stream that can be checked with the command ffplay -loglevel warning -v info -f rawvideo -pixel_format rgb24 \ -video_size "300x700" test.raw Co-developed-by: Gabriela Bittencourt <gabrielabittencourt00@gmail.com> Signed-off-by: Gabriela Bittencourt <gabrielabittencourt00@gmail.com> Co-developed-by: Gabriel Francisco Mandaji <gfmandaji@gmail.com> Signed-off-by: Gabriel Francisco Mandaji <gfmandaji@gmail.com> Signed-off-by: Pedro Terra <pedro@terraco.de> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2021-09-30media: imx7.rst: Provide an example for imx6ull-evk captureFabio Estevam
imx6ull-evk has a parallel OV5640 sensor. Provide an example for imx6ull-evk capture to improve the document. Signed-off-by: Fabio Estevam <festevam@denx.de> Acked-by: Rui Miguel Silva <rmfrfs@gmail.com> Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2021-09-30media: ipu3.rst: Improve header formatting on tablesNícolas F. R. A. Prado
Use the header-rows option of the flat-table directive in order to have the first row displayed as a header. Also capitalize these headers. These changes make the tables easier to read. Signed-off-by: Nícolas F. R. A. Prado <nfraprado@collabora.com> Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2021-09-30media: Rename V4L2_PIX_FMT_HM12 to V4L2_PIX_FMT_NV12_16L16Ezequiel Garcia
The V4L2_PIX_FMT_HM12 format is actually a simple NV12 tiled format, with 16x16 linear tiles. Rename the format and move its documentation together with the other tiled NV12 formats. Keep V4L2_PIX_FMT_HM12 for application compatibility. Signed-off-by: Ezequiel Garcia <ezequiel@collabora.com> Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2021-09-29uapi/linux/prctl: provide macro definitions for the PR_SCHED_CORE type argumentEugene Syromiatnikov
Commit 7ac592aa35a684ff ("sched: prctl() core-scheduling interface") made use of enum pid_type in prctl's arg4; this type and the associated enumeration definitions are not exposed to userspace. Christian has suggested to provide additional macro definitions that convey the meaning of the type argument more in alignment with its actual usage, and this patch does exactly that. Link: https://lore.kernel.org/r/20210825170613.GA3884@asgard.redhat.com Suggested-by: Christian Brauner <christian.brauner@ubuntu.com> Acked-by: Christian Brauner <christian.brauner@ubuntu.com> Signed-off-by: Eugene Syromiatnikov <esyr@redhat.com> Complements: 7ac592aa35a684ff ("sched: prctl() core-scheduling interface") Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-09-27Documentation: update pagemap with shmem exceptionsTiberiu A Georgescu
Mentioning the current missing information in the pagemap and alternatives on how to retrieve it, in case someone stumbles upon unexpected behaviour. 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: David Hildenbrand <david@redhat.com> Reviewed-by: Peter Xu <peterx@redhat.com> Link: https://lore.kernel.org/r/20210923064618.157046-2-tiberiu.georgescu@nutanix.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-09-20docs/cgroup: add entry for misc.eventsChunguang Xu
Added descriptions of misc.events. Signed-off-by: Chunguang Xu <brookxu@tencent.com> Reviewed-by: Michal Koutný <mkoutny@suse.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2021-09-13cgroupv2, docs: fix misinformation in "device controller" sectionArthurChiao
Hotmail was rejected by the mailing list, switched to gmail to resend. 1. Clarify cgroup BPF program type and attach type; 2. Fix file path broken. Signed-off-by: ArthurChiao <arthurchiao@hotmail.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2021-09-13docs/cgroup: remove some duplicate wordsChunguang Xu
When I tried to add some new entries to cgroup-v2.rst, I found that the description of memory.events had some repetitive words, so I tried to delete them. Signed-off-by: Chunguang Xu <brookxu@tencent.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2021-09-13Merge branch 'gcc-min-version-5.1' (make gcc-5.1 the minimum version)Linus Torvalds
Merge patch series from Nick Desaulniers to update the minimum gcc version to 5.1. This is some of the left-overs from the merge window that I didn't want to deal with yesterday, so it comes in after -rc1 but was sent before. Gcc-4.9 support has been an annoyance for some time, and with -Werror I had the choice of applying a fairly big patch from Kees Cook to remove a fair number of initializer warnings (still leaving some), or this patch series from Nick that just removes the source of the problem. The initializer cleanups might still be worth it regardless, but honestly, I preferred just tackling the problem with gcc-4.9 head-on. We've been more aggressiuve about no longer having to care about compilers that were released a long time ago, and I think it's been a good thing. I added a couple of patches on top to sort out a few left-overs now that we no longer support gcc-4.x. As noted by Arnd, as a result of this minimum compiler version upgrade we can probably change our use of '--std=gnu89' to '--std=gnu11', and finally start using local loop declarations etc. But this series does _not_ yet do that. Link: https://lore.kernel.org/all/20210909182525.372ee687@canb.auug.org.au/ Link: https://lore.kernel.org/lkml/CAK7LNASs6dvU6D3jL2GG3jW58fXfaj6VNOe55NJnTB8UPuk2pA@mail.gmail.com/ Link: https://github.com/ClangBuiltLinux/linux/issues/1438 * emailed patches from Nick Desaulniers <ndesaulniers@google.com>: Drop some straggling mentions of gcc-4.9 as being stale compiler_attributes.h: drop __has_attribute() support for gcc4 vmlinux.lds.h: remove old check for GCC 4.9 compiler-gcc.h: drop checks for older GCC versions Makefile: drop GCC < 5 -fno-var-tracking-assignments workaround arm64: remove GCC version check for ARCH_SUPPORTS_INT128 powerpc: remove GCC version check for UPD_CONSTR riscv: remove Kconfig check for GCC version for ARCH_RV64I Kconfig.debug: drop GCC 5+ version check for DWARF5 mm/ksm: remove old GCC 4.9+ check compiler.h: drop fallback overflow checkers Documentation: raise minimum supported version of GCC to 5.1
2021-09-13Drop some straggling mentions of gcc-4.9 as being staleLinus Torvalds
Fix up the admin-guide README file to the new gcc-5.1 requirement, and remove a stale comment about gcc support for the __assume_aligned__ attribute. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-09Merge tag 'trace-v5.15-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull more tracing updates from Steven Rostedt: - Add migrate-disable counter to tracing header - Fix error handling in event probes - Fix missed unlock in osnoise in error path - Fix merge issue with tools/bootconfig - Clean up bootconfig data when init memory is removed - Fix bootconfig to loop only on subkeys - Have kernel command lines override bootconfig options - Increase field counts for synthetic events - Have histograms dynamic allocate event elements to save space - Fixes in testing and documentation * tag 'trace-v5.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing/boot: Fix to loop on only subkeys selftests/ftrace: Exclude "(fault)" in testing add/remove eprobe events tracing: Dynamically allocate the per-elt hist_elt_data array tracing: synth events: increase max fields count tools/bootconfig: Show whole test command for each test case bootconfig: Fix missing return check of xbc_node_compose_key function tools/bootconfig: Fix tracing_on option checking in ftrace2bconf.sh docs: bootconfig: Add how to use bootconfig for kernel parameters init/bootconfig: Reorder init parameter from bootconfig and cmdline init: bootconfig: Remove all bootconfig data when the init memory is removed tracing/osnoise: Fix missed cpus_read_unlock() in start_per_cpu_kthreads() tracing: Fix some alloc_event_probe() error handling bugs tracing: Add migrate-disabled counter to tracing output.
2021-09-09Merge tag 'dmaengine-5.15-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/dmaengine Pull dmaengine updates from Vinod Koul: "New drivers/devices - Support for Renesas RZ/G2L dma controller - New driver for AMD PTDMA controller Updates: - Big pile of idxd updates - Updates for Altera driver, stm32-dma, dw etc" * tag 'dmaengine-5.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/dmaengine: (83 commits) dmaengine: sh: fix some NULL dereferences dmaengine: sh: Fix unused initialization of pointer lmdesc MAINTAINERS: Fix AMD PTDMA DRIVER entry dmaengine: ptdma: remove PT_OFFSET to avoid redefnition dmaengine: ptdma: Add debugfs entries for PTDMA dmaengine: ptdma: register PTDMA controller as a DMA resource dmaengine: ptdma: Initial driver for the AMD PTDMA dmaengine: fsl-dpaa2-qdma: Fix spelling mistake "faile" -> "failed" dmaengine: idxd: remove interrupt disable for dev_lock dmaengine: idxd: remove interrupt disable for cmd_lock dmaengine: idxd: fix setting up priv mode for dwq dmaengine: xilinx_dma: Set DMA mask for coherent APIs dmaengine: ti: k3-psil-j721e: Add entry for CSI2RX dmaengine: sh: Add DMAC driver for RZ/G2L SoC dmaengine: Extend the dma_slave_width for 128 bytes dt-bindings: dma: Document RZ/G2L bindings dmaengine: ioat: depends on !UML dmaengine: idxd: set descriptor allocation size to threshold for swq dmaengine: idxd: make submit failure path consistent on desc freeing dmaengine: idxd: remove interrupt flag for completion list spinlock ...
2021-09-08Merge tag 'acpi-5.15-rc1-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull more ACPI updates from Rafael Wysocki: "These add ACPI support to the PCI VMD driver, improve suspend-to-idle support for AMD platforms and update documentation. Specifics: - Add ACPI support to the PCI VMD driver (Rafael Wysocki) - Rearrange suspend-to-idle support code to reflect the platform firmware expectations on some AMD platforms (Mario Limonciello) - Make SSDT overlays documentation follow the code documented by it more closely (Andy Shevchenko)" * tag 'acpi-5.15-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: ACPI: PM: s2idle: Run both AMD and Microsoft methods if both are supported Documentation: ACPI: Align the SSDT overlays file with the code PCI: VMD: ACPI: Make ACPI companion lookup work for VMD bus
2021-09-08Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge more updates from Andrew Morton: "147 patches, based on 7d2a07b769330c34b4deabeed939325c77a7ec2f. Subsystems affected by this patch series: mm (memory-hotplug, rmap, ioremap, highmem, cleanups, secretmem, kfence, damon, and vmscan), alpha, percpu, procfs, misc, core-kernel, MAINTAINERS, lib, checkpatch, epoll, init, nilfs2, coredump, fork, pids, criu, kconfig, selftests, ipc, and scripts" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (94 commits) scripts: check_extable: fix typo in user error message mm/workingset: correct kernel-doc notations ipc: replace costly bailout check in sysvipc_find_ipc() selftests/memfd: remove unused variable Kconfig.debug: drop selecting non-existing HARDLOCKUP_DETECTOR_ARCH configs: remove the obsolete CONFIG_INPUT_POLLDEV prctl: allow to setup brk for et_dyn executables pid: cleanup the stale comment mentioning pidmap_init(). kernel/fork.c: unexport get_{mm,task}_exe_file coredump: fix memleak in dump_vma_snapshot() fs/coredump.c: log if a core dump is aborted due to changed file permissions nilfs2: use refcount_dec_and_lock() to fix potential UAF nilfs2: fix memory leak in nilfs_sysfs_delete_snapshot_group nilfs2: fix memory leak in nilfs_sysfs_create_snapshot_group nilfs2: fix memory leak in nilfs_sysfs_delete_##name##_group nilfs2: fix memory leak in nilfs_sysfs_create_##name##_group nilfs2: fix NULL pointer in nilfs_##name##_attr_release nilfs2: fix memory leak in nilfs_sysfs_create_device_group trap: cleanup trap_init() init: move usermodehelper_enable() to populate_rootfs() ...
2021-09-08docs: bootconfig: Add how to use bootconfig for kernel parametersMasami Hiramatsu
Add a section to describe how to use the bootconfig for specifying kernel and init parameters. This is an important section because it is the reason why this document is under the admin-guide. Link: https://lkml.kernel.org/r/163077086399.222577.5881779375643977991.stgit@devnote2 Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: linux-doc@vger.kernel.org Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-09-08Documentation: add documents for DAMONSeongJae Park
This commit adds documents for DAMON under `Documentation/admin-guide/mm/damon/` and `Documentation/vm/damon/`. Link: https://lkml.kernel.org/r/20210716081449.22187-11-sj38.park@gmail.com Signed-off-by: SeongJae Park <sjpark@amazon.de> Reviewed-by: Fernand Sieber <sieberf@amazon.com> Reviewed-by: Markus Boehme <markubo@amazon.de> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> 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 Rientjes <rientjes@google.com> Cc: David Woodhouse <dwmw@amazon.com> Cc: Fan Du <fan.du@intel.com> Cc: Greg Kroah-Hartman <greg@kroah.com> Cc: Greg Thelen <gthelen@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Joe Perches <joe@perches.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: Maximilian Heyne <mheyne@amazon.de> Cc: Mel Gorman <mgorman@suse.de> Cc: Minchan Kim <minchan@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@surriel.com> Cc: Shakeel Butt <shakeelb@google.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Steven Rostedt (VMware) <rostedt@goodmis.org> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-08memory-hotplug.rst: complete admin-guide overhaulDavid Hildenbrand
The memory hot(un)plug documentation is outdated and incomplete. Most of the content dates back to 2007, so it's time for a major overhaul. Let's rewrite, reorganize and update most parts of the documentation. In addition to memory hot(un)plug, also add some details regarding ZONE_MOVABLE, with memory hotunplug being one of its main consumers. Drop the file history, that information can more reliably be had from the git log. The style of the document is also properly fixed that e.g., "restview" renders it cleanly now. In the future, we might add some more details about virt users like virtio-mem, the XEN balloon, the Hyper-V balloon and ppc64 dlpar. Link: https://lkml.kernel.org/r/20210707073205.3835-3-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Mike Rapoport <rppt@linux.ibm.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Muchun Song <songmuchun@bytedance.com> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-08memory-hotplug.rst: remove locking details from admin-guideDavid Hildenbrand
Patch series "memory-hotplug.rst: complete admin-guide overhaul", v3. This patch (of 2): We have the same content at Documentation/core-api/memory-hotplug.rst and it doesn't fit into the admin-guide. The documentation was accidentially duplicated when merging. Link: https://lkml.kernel.org/r/20210707073205.3835-1-david@redhat.com Link: https://lkml.kernel.org/r/20210707073205.3835-2-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Acked-by: Mike Rapoport <rppt@linux.ibm.com> Acked-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Muchun Song <songmuchun@bytedance.com> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03Merge tag 'iommu-updates-v5.15' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu Pull iommu updates from Joerg Roedel: - New DART IOMMU driver for Apple Silicon M1 chips - Optimizations for iommu_[map/unmap] performance - Selective TLB flush support for the AMD IOMMU driver to make it more efficient on emulated IOMMUs - Rework IOVA setup and default domain type setting to move more code out of IOMMU drivers and to support runtime switching between certain types of default domains - VT-d Updates from Lu Baolu: - Update the virtual command related registers - Enable Intel IOMMU scalable mode by default - Preset A/D bits for user space DMA usage - Allow devices to have more than 32 outstanding PRs - Various cleanups - ARM SMMU Updates from Will Deacon: SMMUv3: - Minor optimisation to avoid zeroing struct members on CMD submission - Increased use of batched commands to reduce submission latency - Refactoring in preparation for ECMDQ support SMMUv2: - Fix races when probing devices with identical StreamIDs - Optimise walk cache flushing for Qualcomm implementations - Allow deep sleep states for some Qualcomm SoCs with shared clocks - Various smaller optimizations, cleanups, and fixes * tag 'iommu-updates-v5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (85 commits) iommu/io-pgtable: Abstract iommu_iotlb_gather access iommu/arm-smmu: Fix missing unlock on error in arm_smmu_device_group() iommu/vt-d: Add present bit check in pasid entry setup helpers iommu/vt-d: Use pasid_pte_is_present() helper function iommu/vt-d: Drop the kernel doc annotation iommu/vt-d: Allow devices to have more than 32 outstanding PRs iommu/vt-d: Preset A/D bits for user space DMA usage iommu/vt-d: Enable Intel IOMMU scalable mode by default iommu/vt-d: Refactor Kconfig a bit iommu/vt-d: Remove unnecessary oom message iommu/vt-d: Update the virtual command related registers iommu: Allow enabling non-strict mode dynamically iommu: Merge strictness and domain type configs iommu: Only log strictness for DMA domains iommu: Expose DMA domain strictness via sysfs iommu: Express DMA strictness via the domain type iommu/vt-d: Prepare for multiple DMA domain types iommu/arm-smmu: Prepare for multiple DMA domain types iommu/amd: Prepare for multiple DMA domain types iommu: Introduce explicit type for non-strict DMA domains ...
2021-09-03Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge misc updates from Andrew Morton: "173 patches. Subsystems affected by this series: ia64, ocfs2, block, and mm (debug, pagecache, gup, swap, shmem, memcg, selftests, pagemap, mremap, bootmem, sparsemem, vmalloc, kasan, pagealloc, memory-failure, hugetlb, userfaultfd, vmscan, compaction, mempolicy, memblock, oom-kill, migration, ksm, percpu, vmstat, and madvise)" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (173 commits) mm/madvise: add MADV_WILLNEED to process_madvise() mm/vmstat: remove unneeded return value mm/vmstat: simplify the array size calculation mm/vmstat: correct some wrong comments mm/percpu,c: remove obsolete comments of pcpu_chunk_populated() selftests: vm: add COW time test for KSM pages selftests: vm: add KSM merging time test mm: KSM: fix data type selftests: vm: add KSM merging across nodes test selftests: vm: add KSM zero page merging test selftests: vm: add KSM unmerge test selftests: vm: add KSM merge test mm/migrate: correct kernel-doc notation mm: wire up syscall process_mrelease mm: introduce process_mrelease system call memblock: make memblock_find_in_range method private mm/mempolicy.c: use in_task() in mempolicy_slab_node() mm/mempolicy: unify the create() func for bind/interleave/prefer-many policies mm/mempolicy: advertise new MPOL_PREFERRED_MANY mm/hugetlb: add support for mempolicy MPOL_PREFERRED_MANY ...
2021-09-03mm/mempolicy: advertise new MPOL_PREFERRED_MANYBen Widawsky
Adds a new mode to the existing mempolicy modes, MPOL_PREFERRED_MANY. MPOL_PREFERRED_MANY will be adequately documented in the internal admin-guide with this patch. Eventually, the man pages for mbind(2), get_mempolicy(2), set_mempolicy(2) and numactl(8) will also have text about this mode. Those shall contain the canonical reference. NUMA systems continue to become more prevalent. New technologies like PMEM make finer grain control over memory access patterns increasingly desirable. MPOL_PREFERRED_MANY allows userspace to specify a set of nodes that will be tried first when performing allocations. If those allocations fail, all remaining nodes will be tried. It's a straight forward API which solves many of the presumptive needs of system administrators wanting to optimize workloads on such machines. The mode will work either per VMA, or per thread. [Michal Hocko: refine kernel doc for MPOL_PREFERRED_MANY] Link: https://lore.kernel.org/r/20200630212517.308045-13-ben.widawsky@intel.com Link: https://lkml.kernel.org/r/1627970362-61305-5-git-send-email-feng.tang@intel.com Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> Signed-off-by: Feng Tang <feng.tang@intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Rientjes <rientjes@google.com> Cc: Huang Ying <ying.huang@intel.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@kernel.org> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03mm: compaction: support triggering of proactive compaction by userCharan Teja Reddy
The proactive compaction[1] gets triggered for every 500msec and run compaction on the node for COMPACTION_HPAGE_ORDER (usually order-9) pages based on the value set to sysctl.compaction_proactiveness. Triggering the compaction for every 500msec in search of COMPACTION_HPAGE_ORDER pages is not needed for all applications, especially on the embedded system usecases which may have few MB's of RAM. Enabling the proactive compaction in its state will endup in running almost always on such systems. Other side, proactive compaction can still be very much useful for getting a set of higher order pages in some controllable manner(controlled by using the sysctl.compaction_proactiveness). So, on systems where enabling the proactive compaction always may proove not required, can trigger the same from user space on write to its sysctl interface. As an example, say app launcher decide to launch the memory heavy application which can be launched fast if it gets more higher order pages thus launcher can prepare the system in advance by triggering the proactive compaction from userspace. This triggering of proactive compaction is done on a write to sysctl.compaction_proactiveness by user. [1]https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit?id=facdaa917c4d5a376d09d25865f5a863f906234a [akpm@linux-foundation.org: tweak vm.rst, per Mike] Link: https://lkml.kernel.org/r/1627653207-12317-1-git-send-email-charante@codeaurora.org Signed-off-by: Charan Teja Reddy <charante@codeaurora.org> Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Rafael Aquini <aquini@redhat.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Luis Chamberlain <mcgrof@kernel.org> Cc: Kees Cook <keescook@chromium.org> Cc: Iurii Zaikin <yzaikin@google.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Nitin Gupta <nigupta@nvidia.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Khalid Aziz <khalid.aziz@oracle.com> Cc: David Rientjes <rientjes@google.com> Cc: Vinayak Menon <vinmenon@codeaurora.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-02Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdmaLinus Torvalds
Pull rdma updates from Jason Gunthorpe: "This is quite a small cycle, no major series stands out. The HNS and rxe drivers saw the most activity this cycle, with rxe being broken for a good chunk of time. The significant deleted line count is due to a SPDX cleanup series. Summary: - Various cleanup and small features for rtrs - kmap_local_page() conversions - Driver updates and fixes for: efa, rxe, mlx5, hfi1, qed, hns - Cache the IB subnet prefix - Rework how CRC is calcuated in rxe - Clean reference counting in iwpm's netlink - Pull object allocation and lifecycle for user QPs to the uverbs core code - Several small hns features and continued general code cleanups - Fix the scatterlist confusion of orig_nents/nents introduced in an earlier patch creating the append operation" * tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma: (90 commits) RDMA/mlx5: Relax DCS QP creation checks RDMA/hns: Delete unnecessary blank lines. RDMA/hns: Encapsulate the qp db as a function RDMA/hns: Adjust the order in which irq are requested and enabled RDMA/hns: Remove RST2RST error prints for hw v1 RDMA/hns: Remove dqpn filling when modify qp from Init to Init RDMA/hns: Fix QP's resp incomplete assignment RDMA/hns: Fix query destination qpn RDMA/hfi1: Convert to SPDX identifier IB/rdmavt: Convert to SPDX identifier RDMA/hns: Bugfix for incorrect association between dip_idx and dgid RDMA/hns: Bugfix for the missing assignment for dip_idx RDMA/hns: Bugfix for data type of dip_idx RDMA/hns: Fix incorrect lsn field RDMA/irdma: Remove the repeated declaration RDMA/core/sa_query: Retry SA queries RDMA: Use the sg_table directly and remove the opencoded version from umem lib/scatterlist: Fix wrong update of orig_nents lib/scatterlist: Provide a dedicated function to support table append RDMA/hns: Delete unused hns bitmap interface ...
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