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2021-12-17Documentation, arch: Remove leftovers from raw deviceAlexandre Ghiti1-7/+1
Raw device interface was removed so remove all references to configs related to it. Fixes: 603e4922f1c8 ("remove the raw driver") Signed-off-by: Alexandre Ghiti <alexandre.ghiti@canonical.com> Acked-by: Arnd Bergmann <arnd@arndb.de> [arch/arm/configs] Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2021-12-17gpio: sim: new testing moduleBartosz Golaszewski1-0/+134
Implement a new, modern GPIO testing module controlled by configfs attributes instead of module parameters. The goal of this driver is to provide a replacement for gpio-mockup that will be easily extensible with new features and doesn't require reloading the module to change the setup. Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl> Acked-by: Linus Walleij <linus.walleij@linaro.org>
2021-12-14Merge branch 'for-next/perf-user-counter-access' into for-next/perfWill Deacon1-0/+11
* for-next/perf-user-counter-access: Documentation: arm64: Document PMU counters access from userspace arm64: perf: Enable PMU counter userspace access for perf event arm64: perf: Add userspace counter access disable switch perf: Add a counter for number of user access events in context x86: perf: Move RDPMC event flag to a common definition
2021-12-14docs: perf: Add description for HiSilicon PCIe PMU driverQi Liu1-0/+106
PCIe PMU Root Complex Integrated End Point(RCiEP) device is supported on HiSilicon HIP09 platform. Document it to provide guidance on how to use it. Reviewed-by: John Garry <john.garry@huawei.com> Signed-off-by: Qi Liu <liuqi115@huawei.com> Reviewed-by: Shaokun Zhang <zhangshaokun@hisilicon.com> Link: https://lore.kernel.org/r/20211202080633.2919-2-liuqi115@huawei.com Signed-off-by: Will Deacon <will@kernel.org>
2021-12-14arm64: perf: Add userspace counter access disable switchRob Herring1-0/+11
Like x86, some users may want to disable userspace PMU counter altogether. Add a sysctl 'perf_user_access' file to control userspace counter access. The default is '0' which is disabled. Writing '1' enables access. Note that x86 supports globally enabling user access by writing '2' to /sys/bus/event_source/devices/cpu/rdpmc. As there's not existing userspace support to worry about, this shouldn't be necessary for Arm. It could be added later if the need arises. Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: linux-perf-users@vger.kernel.org Acked-by: Will Deacon <will@kernel.org> Reviewed-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Rob Herring <robh@kernel.org> Link: https://lore.kernel.org/r/20211208201124.310740-4-robh@kernel.org Signed-off-by: Will Deacon <will@kernel.org>
2021-12-14Merge v5.16-rc5 into drm-nextDaniel Vetter2-7/+2
Thomas Zimmermann requested a fixes backmerge, specifically also for 96c5f82ef0a1 ("drm/vc4: fix error code in vc4_create_object()") Just a bunch of adjacent changes conflicts, even the big pile of them in vc4. Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2021-12-10Merge tag 'v5.16-rc4' into docs-nextJonathan Corbet1-6/+6
I have a couple of fixes for warnings introduced after -rc1; catch up to -rc4 so that the fixes have something to fix.
2021-12-09Merge branches 'doc.2021.11.30c', 'exp.2021.12.07a', 'fastnohz.2021.11.30c', 'fixes.2021.11.30c', 'nocb.2021.12.09a', 'nolibc.2021.11.30c', 'tasks.2021.12.09a', 'torture.2021.12.07a' and 'torturescript.2021.11.30c' into HEADPaul E. McKenney1-18/+52
doc.2021.11.30c: Documentation updates. exp.2021.12.07a: Expedited-grace-period fixes. fastnohz.2021.11.30c: Remove CONFIG_RCU_FAST_NO_HZ. fixes.2021.11.30c: Miscellaneous fixes. nocb.2021.12.09a: No-CB CPU updates. nolibc.2021.11.30c: Tiny in-kernel library updates. tasks.2021.12.09a: RCU-tasks updates, including update-side scalability. torture.2021.12.07a: Torture-test in-kernel module updates. torturescript.2021.11.30c: Torture-test scripting updates.
2021-12-09rcu/nocb: Allow empty "rcu_nocbs" kernel parameterFrederic Weisbecker1-13/+24
Allow the rcu_nocbs kernel parameter to be specified just by itself, without specifying any CPUs. This allows systems administrators to use "rcu_nocbs" to specify that none of the CPUs are to be offloaded at boot time, but than any of them may be offloaded at runtime via cpusets. In contrast, if the "rcu_nocbs" or "nohz_full" kernel parameters are not specified at all, then not only are none of the CPUs offloaded at boot, none of them can be offloaded at runtime, either. While in the area, modernize the description of the "rcuo" kthreads' naming scheme. Reviewed-by: Neeraj Upadhyay <quic_neeraju@quicinc.com> Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Cc: Boqun Feng <boqun.feng@gmail.com> Cc: Uladzislau Rezki <urezki@gmail.com> Cc: Josh Triplett <josh@joshtriplett.org> Cc: Joel Fernandes <joel@joelfernandes.org> Tested-by: Juri Lelli <juri.lelli@redhat.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-12-09rcu-tasks: Use fewer callbacks queues if callback flood endsPaul E. McKenney1-0/+8
By default, when lock contention is encountered, the RCU Tasks flavors of RCU switch to using per-CPU queueing. However, if the callback flood ends, per-CPU queueing continues to be used, which introduces significant additional overhead, especially for callback invocation, which fans out a series of workqueue handlers. This commit therefore switches back to single-queue operation if at the beginning of a grace period there are very few callbacks. The definition of "very few" is set by the rcupdate.rcu_task_collapse_lim module parameter, which defaults to 10. This switch happens in two phases, with the first phase causing future callbacks to be enqueued on CPU 0's queue, but with all queues continuing to be checked for grace periods and callback invocation. The second phase checks to see if an RCU grace period has elapsed and if all remaining RCU-Tasks callbacks are queued on CPU 0. If so, only CPU 0 is checked for future grace periods and callback operation. Of course, the return of contention anywhere during this process will result in returning to per-CPU callback queueing. Reported-by: Martin Lau <kafai@fb.com> Cc: Neeraj Upadhyay <neeraj.iitr10@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-12-09rcu-tasks: Use more callback queues if contention encounteredPaul E. McKenney1-0/+8
The rcupdate.rcu_task_enqueue_lim module parameter allows system administrators to tune the number of callback queues used by the RCU Tasks flavors. However if callback storms are infrequent, it would be better to operate with a single queue on a given system unless and until that system actually needed more queues. Systems not needing more queues can then avoid the overhead of checking the extra queues and especially avoid the overhead of fanning workqueue handlers out to all CPUs to invoke callbacks. This commit therefore switches to using all the CPUs' callback queues if call_rcu_tasks_generic() encounters too much lock contention. The amount of lock contention to tolerate defaults to 100 contended lock acquisitions per jiffy, and can be adjusted using the new rcupdate.rcu_task_contend_lim module parameter. Such switching is undertaken only if the rcupdate.rcu_task_enqueue_lim module parameter is negative, which is its default value (-1). This allows savvy systems administrators to set the number of queues to some known good value and to not have to worry about the kernel doing any second guessing. [ paulmck: Apply feedback from Guillaume Tucker and kernelci. ] Reported-by: Martin Lau <kafai@fb.com> Cc: Neeraj Upadhyay <neeraj.iitr10@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-12-09rcu-tasks: Add rcupdate.rcu_task_enqueue_lim to set initial queueingPaul E. McKenney1-0/+7
This commit adds a rcupdate.rcu_task_enqueue_lim module parameter that sets the initial number of callback queues to use for the RCU Tasks family of RCU implementations. This parameter allows testing of various fanout values. Reported-by: Martin Lau <kafai@fb.com> Cc: Neeraj Upadhyay <neeraj.iitr10@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-12-09powerpc/kuep: Remove 'nosmep' boot time parameter except for book3s/64Christophe Leroy1-1/+1
Deactivating KUEP at boot time is unrelevant for PPC32 and BOOK3E/64. Remove it. It allows to refactor setup_kuep() via a __weak function that only PPC64s will overide for now. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> [mpe: Fix CONFIG_PPC_BOOKS_64 -> CONFIG_PPC_BOOK3S_64 typo] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/4c36df18b41c988c4512f45d96220486adbe4c99.1634627931.git.christophe.leroy@csgroup.eu
2021-12-09Merge tag 'drm-misc-next-2021-11-29' of git://anongit.freedesktop.org/drm/drm-misc into drm-nextDaniel Vetter1-0/+7
drm-misc-next for 5.17: UAPI Changes: Cross-subsystem Changes: * Move 'nomodeset' kernel boot option into DRM subsystem Core Changes: * Replace several DRM_*() logging macros with drm_*() equivalents * panel: Add quirk for Lenovo Yoga Book X91F/L * ttm: Documentation fixes Driver Changes: * Cleanup nomodeset handling in drivers * Fixes * bridge/anx7625: Fix reading EDID; Fix error code * bridge/megachips: Probe both bridges before registering * vboxvideo: Fix ERR_PTR usage Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> From: Thomas Zimmermann <tzimmermann@suse.de> Link: https://patchwork.freedesktop.org/patch/msgid/YaSVz15Q7dAlEevU@linux-uq9g.fritz.box
2021-12-08PM: hibernate: Allow ACPI hardware signature to be honouredDavid Woodhouse1-3/+12
Theoretically, when the hardware signature in FACS changes, the OS is supposed to gracefully decline to attempt to resume from S4: "If the signature has changed, OSPM will not restore the system context and can boot from scratch" In practice, Windows doesn't do this and many laptop vendors do allow the signature to change especially when docking/undocking, so it would be a bad idea to simply comply with the specification by default in the general case. However, there are use cases where we do want the compliant behaviour and we know it's safe. Specifically, when resuming virtual machines where we know the hypervisor has changed sufficiently that resume will fail. We really want to be able to *tell* the guest kernel not to try, so it boots cleanly and doesn't just crash. This patch provides a way to opt in to the spec-compliant behaviour on the command line. A follow-up patch may do this automatically for certain "known good" machines based on a DMI match, or perhaps just for all hypervisor guests since there's no good reason a hypervisor would change the hardware_signature that it exposes to guests *unless* it wants them to obey the ACPI specification. Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-12-07rcutorture: Enable multiple concurrent callback-flood kthreadsPaul E. McKenney1-1/+5
This commit converts the rcutorture.fwd_progress module parameter from bool to int, so that it specifies the number of callback-flood kthreads. Values less than zero specify one kthread per CPU, however, the number of kthreads executing concurrently is limited to the number of online CPUs. This commit also reverse the order of the need-resched and callback-flood operations to cause the callback flooding to happen more nearly at the same time. Cc: Neeraj Upadhyay <neeraj.iitr10@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-12-07Merge tag 'v5.16-rc4' into media_treeMauro Carvalho Chehab2-7/+7
Linux 5.16-rc4 * tag 'v5.16-rc4': (984 commits) Linux 5.16-rc4 KVM: SVM: Do not terminate SEV-ES guests on GHCB validation failure KVM: SEV: Fall back to vmalloc for SEV-ES scratch area if necessary KVM: SEV: Return appropriate error codes if SEV-ES scratch setup fails parisc: Mark cr16 CPU clocksource unstable on all SMP machines parisc: Fix "make install" on newer debian releases sched/uclamp: Fix rq->uclamp_max not set on first enqueue preempt/dynamic: Fix setup_preempt_mode() return value cifs: avoid use of dstaddr as key for fscache client cookie cifs: add server conn_id to fscache client cookie cifs: wait for tcon resource_id before getting fscache super cifs: fix missed refcounting of ipc tcon x86/xen: Add xenpv_restore_regs_and_return_to_usermode() x86/entry: Use the correct fence macro after swapgs in kernel CR3 fget: check that the fd still exists after getting a ref to it x86/entry: Add a fence for kernel entry SWAPGS in paranoid_entry() x86/sev: Fix SEV-ES INS/OUTS instructions for word, dword, and qword powercap: DTPM: Drop unused local variable from init_dtpm() io-wq: don't retry task_work creation failure on fatal conditions serial: 8250_bcm7271: UART errors after resuming from S2 ...
2021-12-07topology/sysfs: get rid of htmldoc warningHeiko Carstens1-9/+9
Stephen Rothwell reported the following warning caused by commit f1045056c726 ("topology/sysfs: rework book and drawer topology ifdefery"): Documentation/admin-guide/cputopology.rst:49: WARNING: Block quote ends without a blank line; unexpected unindent. To fix this remove the extra indentation again. Fixes: f1045056c726 ("topology/sysfs: rework book and drawer topology ifdefery") Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Link: https://lore.kernel.org/r/Ya4Ht2K9x2+lUtuR@osiris Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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
2021-12-03topology/sysfs: rework book and drawer topology ifdeferyHeiko Carstens1-21/+15
Provide default defines for the topology_book_[id|cpumask] and topology_drawer_[id|cpumask] macros just like for each other topology level. This way all topology levels are handled in a similar way. Still the the book and drawer levels are only used on s390, and also the sysfs attributes are only created on s390. However other architectures may opt in if wanted. Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Link: https://lore.kernel.org/r/20211129130309.3256168-4-hca@linux.ibm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-12-03topology/sysfs: export cluster attributes only if an architectures has supportHeiko Carstens1-2/+2
The cluster_id and cluster_cpus topology sysfs attributes have been added with commit c5e22feffdd7 ("topology: Represent clusters of CPUs within a die"). They are currently only used for x86, arm64, and riscv (via generic arch topology), however they are still present with bogus default values for all other architectures. Instead of enforcing such new sysfs attributes to all architectures, make them only optional visible if an architecture opts in by defining both the topology_cluster_id and topology_cluster_cpumask attributes. This is similar to what was done when the book and drawer topology levels were introduced: avoid useless and therefore confusing sysfs attributes for architectures which cannot make use of them. This should not break any existing applications, since this is a new interface introduced with the v5.16 merge window. Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Link: https://lore.kernel.org/r/20211129130309.3256168-3-hca@linux.ibm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-12-03topology/sysfs: export die attributes only if an architectures has supportHeiko Carstens1-0/+3
The die_id and die_cpus topology sysfs attributes have been added with commit 0e344d8c709f ("cpu/topology: Export die_id") and commit 2e4c54dac7b3 ("topology: Create core_cpus and die_cpus sysfs attributes"). While they are currently only used and useful for x86 they are still present with bogus default values for all architectures. Instead of enforcing such new sysfs attributes to all architectures, make them only optional visible if an architecture opts in by defining both the topology_die_id and topology_die_cpumask attributes. This is similar to what was done when the book and drawer topology levels were introduced: avoid useless and therefore confusing sysfs attributes for architectures which cannot make use of them. This should not break any existing applications, since this is a rather new interface and applications should be able to handle also older kernel versions without such attributes - besides that they contain only useful information for x86. Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Link: https://lore.kernel.org/r/20211129130309.3256168-2-hca@linux.ibm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-30rcu: Remove the RCU_FAST_NO_HZ Kconfig optionPaul E. McKenney1-4/+0
All of the uses of CONFIG_RCU_FAST_NO_HZ=y that I have seen involve systems with RCU callbacks offloaded. In this situation, all that this Kconfig option does is slow down idle entry/exit with an additional allways-taken early exit. If this is the only use case, then this Kconfig option nothing but an attractive nuisance that needs to go away. This commit therefore removes the RCU_FAST_NO_HZ Kconfig option. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-11-30doc: Remove obsolete kernel-per-CPU-kthreads RCU_FAST_NO_HZ advicePaul E. McKenney1-1/+1
This document advises building with both CONFIG_NO_HZ=y and CONFIG_RCU_FAST_NO_HZ=y. However, CONFIG_NO_HZ=y offloads callbacks from all nohz_full CPUs, and CPUs with offloaded callbacks do not benefit from CONFIG_RCU_FAST_NO_HZ=y. Quite the opposite: CONFIG_RCU_FAST_NO_HZ=y simply adds a bit of idle entry/exit overhead. This commit therefore changes that advice to only CONFIG_NO_HZ=y. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-11-30clocksource: Reduce the default clocksource_watchdog() retries to 2Waiman Long1-2/+2
With the previous patch, there is an extra watchdog read in each retry. Now the total number of clocksource reads is increased to 4 per iteration. In order to avoid increasing the clock skew check overhead, the default maximum number of retries is reduced from 3 to 2 to maintain the same 12 clocksource reads in the worst case. Suggested-by: Paul E. McKenney <paulmck@kernel.org> Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
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>
2021-11-29m68k: Enable memtest functionalityFinn Thain1-1/+1
Enable the memtest functionality and rearrange some code to prevent it from clobbering the initrd. The code to implement CONFIG_BLK_DEV_INITRD was conditional on !defined(CONFIG_SUN3). For simplicity, remove that test on the basis that m68k_ramdisk.size == 0 on Sun 3. The SLIME source code at http://sammy.net/sun3/ftp/pub/m68k/sun3/slime/slime-2.0.tar.gz indicates that no BI_RAMDISK entry is ever passed to the kernel due to #ifdef 0 around the relevant code. Cc: Mike Rapoport <rppt@kernel.org> Cc: Sam Creasey <sammy@sammy.net> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Finn Thain <fthain@linux-m68k.org> Acked-by: Mike Rapoport <rppt@linux.ibm.com> Link: https://lore.kernel.org/r/8170fe1d1c62426d82275d36ba409ecc18754292.1637274578.git.fthain@linux-m68k.org Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
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>
2021-11-27Documentation/admin-guide: Document nomodeset kernel parameterJavier Martinez Canillas1-0/+7
The nomodeset kernel command line parameter is not documented. Its name is quite vague and is not intuitive what's the behaviour when it is set. Document in kernel-parameters.txt what actually happens when nomodeset is used. That way, users could know if they want to enable this option. Signed-off-by: Javier Martinez Canillas <javierm@redhat.com> Acked-by: Thomas Zimmermann <tzimmermann@suse.de> Acked-by: Jani Nikula <jani.nikula@intel.com> Acked-by: Pekka Paalanen <pekka.paalanen@collabora.com> Link: https://patchwork.freedesktop.org/patch/msgid/20211112133230.1595307-6-javierm@redhat.com
2021-11-25powerpc/xive: Add a kernel parameter for StoreEOICédric Le Goater1-0/+6
StoreEOI is activated by default on platforms supporting the feature (POWER10) and will be used as soon as firmware advertises its availability. The kernel parameter provides a way to deactivate its use. It can be still be reactivated through debugfs. Signed-off-by: Cédric Le Goater <clg@kaod.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211105102636.1016378-10-clg@kaod.org
2021-11-24powerpc/64s: Implement PMU override command line optionNicholas Piggin1-0/+8
It can be useful in simulators (with very constrained environments) to allow some PMCs to run from boot so they can be sampled directly by a test harness, rather than having to run perf. A previous change freezes counters at boot by default, so provide a boot time option to un-freeze (plus a bit more flexibility). Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Athira Jajeev <atrajeev@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211123095231.1036501-13-npiggin@gmail.com
2021-11-18Merge tag 'platform-drivers-x86-v5.16-2' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86Linus Torvalds1-6/+6
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>
2021-11-15media: admin-guide: add stm32-dma2d descriptionDillon Min1-0/+1
add stm32-dma2d description for dma2d driver Signed-off-by: Dillon Min <dillon.minfei@gmail.com> Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
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 git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linuxLinus Torvalds1-2/+3
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 git://git.kernel.org/pub/scm/linux/kernel/git/xen/tipLinus Torvalds1-0/+7
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 git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fsLinus Torvalds2-0/+79
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 git://git.kernel.org/pub/scm/linux/kernel/git/s390/linuxLinus Torvalds1-0/+12
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>