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2019-07-09Merge tag 'docs-5.3' of git://git.lwn.net/linuxLinus Torvalds
Pull Documentation updates from Jonathan Corbet: "It's been a relatively busy cycle for docs: - A fair pile of RST conversions, many from Mauro. These create more than the usual number of simple but annoying merge conflicts with other trees, unfortunately. He has a lot more of these waiting on the wings that, I think, will go to you directly later on. - A new document on how to use merges and rebases in kernel repos, and one on Spectre vulnerabilities. - Various improvements to the build system, including automatic markup of function() references because some people, for reasons I will never understand, were of the opinion that :c:func:``function()`` is unattractive and not fun to type. - We now recommend using sphinx 1.7, but still support back to 1.4. - Lots of smaller improvements, warning fixes, typo fixes, etc" * tag 'docs-5.3' of git://git.lwn.net/linux: (129 commits) docs: automarkup.py: ignore exceptions when seeking for xrefs docs: Move binderfs to admin-guide Disable Sphinx SmartyPants in HTML output doc: RCU callback locks need only _bh, not necessarily _irq docs: format kernel-parameters -- as code Doc : doc-guide : Fix a typo platform: x86: get rid of a non-existent document Add the RCU docs to the core-api manual Documentation: RCU: Add TOC tree hooks Documentation: RCU: Rename txt files to rst Documentation: RCU: Convert RCU UP systems to reST Documentation: RCU: Convert RCU linked list to reST Documentation: RCU: Convert RCU basic concepts to reST docs: filesystems: Remove uneeded .rst extension on toctables scripts/sphinx-pre-install: fix out-of-tree build docs: zh_CN: submitting-drivers.rst: Remove a duplicated Documentation/ Documentation: PGP: update for newer HW devices Documentation: Add section about CPU vulnerabilities for Spectre Documentation: platform: Delete x86-laptop-drivers.txt docs: Note that :c:func: should no longer be used ...
2019-07-08Merge branch 'for-5.3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup Pull cgroup updates from Tejun Heo: "Documentation updates and the addition of cgroup_parse_float() which will be used by new controllers including blk-iocost" * 'for-5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: docs: cgroup-v1: convert docs to ReST and rename to *.rst cgroup: Move cgroup_parse_float() implementation out of CONFIG_SYSFS cgroup: add cgroup_parse_float()
2019-07-08Merge branch 'core-rcu-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull RCU updates from Ingo Molnar: "The changes in this cycle are: - RCU flavor consolidation cleanups and optmizations - Documentation updates - Miscellaneous fixes - SRCU updates - RCU-sync flavor consolidation - Torture-test updates - Linux-kernel memory-consistency-model updates, most notably the addition of plain C-language accesses" * 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (61 commits) tools/memory-model: Improve data-race detection tools/memory-model: Change definition of rcu-fence tools/memory-model: Expand definition of barrier tools/memory-model: Do not use "herd" to refer to "herd7" tools/memory-model: Fix comment in MP+poonceonces.litmus Documentation: atomic_t.txt: Explain ordering provided by smp_mb__{before,after}_atomic() rcu: Don't return a value from rcu_assign_pointer() rcu: Force inlining of rcu_read_lock() rcu: Fix irritating whitespace error in rcu_assign_pointer() rcu: Upgrade sync_exp_work_done() to smp_mb() rcutorture: Upper case solves the case of the vanishing NULL pointer torture: Suppress propagating trace_printk() warning rcutorture: Dump trace buffer for callback pipe drain failures torture: Add --trust-make to suppress "make clean" torture: Make --cpus override idleness calculations torture: Run kernel build in source directory torture: Add function graph-tracing cheat sheet torture: Capture qemu output rcutorture: Tweak kvm options rcutorture: Add trivial RCU implementation ...
2019-07-08docs: Move binderfs to admin-guideMatthew Wilcox (Oracle)
The documentation is more appropriate for the administrator than for the internal kernel API section it is currently in. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Acked-by: Christian Brauner <christian@brauner.io> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-07-08Merge branch 'x86-entry-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 vsyscall updates from Thomas Gleixner: "Further hardening of the legacy vsyscall by providing support for execute only mode and switching the default to it. This prevents a certain class of attacks which rely on the vsyscall page being accessible at a fixed address in the canonical kernel address space" * 'x86-entry-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: selftests/x86: Add a test for process_vm_readv() on the vsyscall page x86/vsyscall: Add __ro_after_init to global variables x86/vsyscall: Change the default vsyscall mode to xonly selftests/x86/vsyscall: Verify that vsyscall=none blocks execution x86/vsyscall: Document odd SIGSEGV error code for vsyscalls x86/vsyscall: Show something useful on a read fault x86/vsyscall: Add a new vsyscall=xonly mode Documentation/admin: Remove the vsyscall=native documentation
2019-06-28Merge branch 'for-mingo' of ↵Ingo Molnar
git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu Pull rcu/next + tools/memory-model changes from Paul E. McKenney: - RCU flavor consolidation cleanups and optmizations - Documentation updates - Miscellaneous fixes - SRCU updates - RCU-sync flavor consolidation - Torture-test updates - Linux-kernel memory-consistency-model updates, most notably the addition of plain C-language accesses Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-28docs: format kernel-parameters -- as codeStephen Kitt
The current ReStructuredText formatting results in "--", used to indicate the end of the kernel command-line parameters, appearing as an en-dash instead of two hyphens; this patch formats them as code, "``--``", as done elsewhere in the documentation. Signed-off-by: Stephen Kitt <steve@sk2.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-06-28x86/vsyscall: Add a new vsyscall=xonly modeAndy Lutomirski
With vsyscall emulation on, a readable vsyscall page is still exposed that contains syscall instructions that validly implement the vsyscalls. This is required because certain dynamic binary instrumentation tools attempt to read the call targets of call instructions in the instrumented code. If the instrumented code uses vsyscalls, then the vsyscall page needs to contain readable code. Unfortunately, leaving readable memory at a deterministic address can be used to help various ASLR bypasses, so some hardening value can be gained by disallowing vsyscall reads. Given how rarely the vsyscall page needs to be readable, add a mechanism to make the vsyscall page be execute only. Signed-off-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: Florian Weimer <fweimer@redhat.com> Cc: Jann Horn <jannh@google.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Kernel Hardening <kernel-hardening@lists.openwall.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lkml.kernel.org/r/d17655777c21bc09a7af1bbcf74e6f2b69a51152.1561610354.git.luto@kernel.org
2019-06-28Documentation/admin: Remove the vsyscall=native documentationAndy Lutomirski
The vsyscall=native feature is gone -- remove the docs. Fixes: 076ca272a14c ("x86/vsyscall/64: Drop "native" vsyscalls") Signed-off-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Kees Cook <keescook@chromium.org> Cc: Florian Weimer <fweimer@redhat.com> Cc: Jann Horn <jannh@google.com> Cc: stable@vger.kernel.org Cc: Borislav Petkov <bp@alien8.de> Cc: Kernel Hardening <kernel-hardening@lists.openwall.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lkml.kernel.org/r/d77c7105eb4c57c1a95a95b6a5b8ba194a18e764.1561610354.git.luto@kernel.org
2019-06-26Documentation: Add section about CPU vulnerabilities for SpectreTim Chen
Add documentation for Spectre vulnerability and the mitigation mechanisms: - Explain the problem and risks - Document the mitigation mechanisms - Document the command line controls - Document the sysfs files Co-developed-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Andi Kleen <ak@linux.intel.com> Co-developed-by: Tim Chen <tim.c.chen@linux.intel.com> Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-06-14docs: EDID/HOWTO.txt: convert it and rename to howto.rstMauro Carvalho Chehab
Sphinx need to know when a paragraph ends. So, do some adjustments at the file for it to be properly parsed. At its new index.rst, let's add a :orphan: while this is not linked to the main index.rst file, in order to avoid build warnings. that's said, I believe that this file should be moved to the GPU/DRM documentation. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-06-14docs: watchdog: convert docs to ReST and rename to *.rstMauro Carvalho Chehab
Convert those documents and prepare them to be part of the kernel API book, as most of the stuff there are related to the Kernel interfaces. Still, in the future, it would make sense to split the docs, as some of the stuff is clearly focused on sysadmin tasks. The conversion is actually: - add blank lines and identation in order to identify paragraphs; - fix tables markups; - add some lists markups; - mark literal blocks; - adjust title markups. At its new index.rst, let's add a :orphan: while this is not linked to the main index.rst file, in order to avoid build warnings. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-06-14docs: cgroup-v1: convert docs to ReST and rename to *.rstMauro Carvalho Chehab
Convert the cgroup-v1 files to ReST format, in order to allow a later addition to the admin-guide. The conversion is actually: - add blank lines and identation in order to identify paragraphs; - fix tables markups; - add some lists markups; - mark literal blocks; - adjust title markups. At its new index.rst, let's add a :orphan: while this is not linked to the main index.rst file, in order to avoid build warnings. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2019-06-14docs: kdump: convert docs to ReST and rename to *.rstMauro Carvalho Chehab
Convert kdump documentation to ReST and add it to the user faced manual, as the documents are mainly focused on sysadmins that would be enabling kdump. Note: the vmcoreinfo.rst has one very long title on one of its sub-sections: PG_lru|PG_private|PG_swapcache|PG_swapbacked|PG_slab|PG_hwpoision|PG_head_mask|PAGE_BUDDY_MAPCOUNT_VALUE(~PG_buddy)|PAGE_OFFLINE_MAPCOUNT_VALUE(~PG_offline) I opted to break this one, into two entries with the same content, in order to make it easier to display after being parsed in html and PDF. The conversion is actually: - add blank lines and identation in order to identify paragraphs; - fix tables markups; - add some lists markups; - mark literal blocks; - adjust title markups. At its new index.rst, let's add a :orphan: while this is not linked to the main index.rst file, in order to avoid build warnings. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-06-14docs: kbuild: convert docs to ReST and rename to *.rstMauro Carvalho Chehab
The kbuild documentation clearly shows that the documents there are written at different times: some use markdown, some use their own peculiar logic to split sections. Convert everything to ReST without affecting too much the author's style and avoiding adding uneeded markups. The conversion is actually: - add blank lines and identation in order to identify paragraphs; - fix tables markups; - add some lists markups; - mark literal blocks; - adjust title markups. At its new index.rst, let's add a :orphan: while this is not linked to the main index.rst file, in order to avoid build warnings. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-06-14docs: ide: convert docs to ReST and rename to *.rstMauro Carvalho Chehab
The conversion is actually: - add blank lines and identation in order to identify paragraphs; - fix tables markups; - add some lists markups; - mark literal blocks; - adjust title markups. At its new index.rst, let's add a :orphan: while this is not linked to the main index.rst file, in order to avoid build warnings. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-06-14docs: fb: convert docs to ReST and rename to *.rstMauro Carvalho Chehab
The conversion is actually: - add blank lines and identation in order to identify paragraphs; - fix tables markups; - add some lists markups; - mark literal blocks; - adjust title markups. At its new index.rst, let's add a :orphan: while this is not linked to the main index.rst file, in order to avoid build warnings. Also, removed the Maintained by, as requested by Geert. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-06-14Merge tag 'v5.2-rc4' into mauroJonathan Corbet
We need to pick up post-rc1 changes to various document files so they don't get lost in Mauro's massive RST conversion push.
2019-06-11docs: s390: convert docs to ReST and rename to *.rstMauro Carvalho Chehab
Convert all text files with s390 documentation to ReST format. Tried to preserve as much as possible the original document format. Still, some of the files required some work in order for it to be visible on both plain text and after converted to html. The conversion is actually: - add blank lines and identation in order to identify paragraphs; - fix tables markups; - add some lists markups; - mark literal blocks; - adjust title markups. At its new index.rst, let's add a :orphan: while this is not linked to the main index.rst file, in order to avoid build warnings. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2019-06-08docs: isdn: remove hisax references from kernel-parameters.txtMauro Carvalho Chehab
The hisax driver got removed on 85993b8c9786 ("isdn: remove hisax driver"), but a left-over was kept at kernel-parameters.txt. Fixes: 85993b8c9786 ("isdn: remove hisax driver") Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-06-08docs: fix broken documentation linksMauro Carvalho Chehab
Mostly due to x86 and acpi conversion, several documentation links are still pointing to the old file. Fix them. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Reviewed-by: Wolfram Sang <wsa@the-dreams.de> Reviewed-by: Sven Van Asbroeck <TheSven73@gmail.com> Reviewed-by: Bhupesh Sharma <bhsharma@redhat.com> Acked-by: Mark Brown <broonie@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-06-08docs: mm: numaperf.rst: get rid of a build warningMauro Carvalho Chehab
When building it, it gets this warning: Documentation/admin-guide/mm/numaperf.rst:168: WARNING: Footnote [1] is not referenced. The problem is that this is not really a reference, as it is not mentioned within the documentation. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-06-01mm, memcg: consider subtrees in memory.eventsChris Down
memory.stat and other files already consider subtrees in their output, and we should too in order to not present an inconsistent interface. The current situation is fairly confusing, because people interacting with cgroups expect hierarchical behaviour in the vein of memory.stat, cgroup.events, and other files. For example, this causes confusion when debugging reclaim events under low, as currently these always read "0" at non-leaf memcg nodes, which frequently causes people to misdiagnose breach behaviour. The same confusion applies to other counters in this file when debugging issues. Aggregation is done at write time instead of at read-time since these counters aren't hot (unlike memory.stat which is per-page, so it does it at read time), and it makes sense to bundle this with the file notifications. After this patch, events are propagated up the hierarchy: [root@ktst ~]# cat /sys/fs/cgroup/system.slice/memory.events low 0 high 0 max 0 oom 0 oom_kill 0 [root@ktst ~]# systemd-run -p MemoryMax=1 true Running as unit: run-r251162a189fb4562b9dabfdc9b0422f5.service [root@ktst ~]# cat /sys/fs/cgroup/system.slice/memory.events low 0 high 0 max 7 oom 1 oom_kill 1 As this is a change in behaviour, this can be reverted to the old behaviour by mounting with the `memory_localevents' flag set. However, we use the new behaviour by default as there's a lack of evidence that there are any current users of memory.events that would find this change undesirable. akpm: this is a behaviour change, so Cc:stable. THis is so that forthcoming distros which use cgroup v2 are more likely to pick up the revised behaviour. Link: http://lkml.kernel.org/r/20190208224419.GA24772@chrisdown.name Signed-off-by: Chris Down <chris@chrisdown.name> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Shakeel Butt <shakeelb@google.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Tejun Heo <tj@kernel.org> Cc: Roman Gushchin <guro@fb.com> Cc: Dennis Zhou <dennis@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-31cgroup: add cgroup_parse_float()Tejun Heo
cgroup already uses floating point for percent[ile] numbers and there are several controllers which want to take them as input. Add a generic parse helper to handle inputs. Update the interface convention documentation about the use of percentage numbers. While at it, also clarify the default time unit. Signed-off-by: Tejun Heo <tj@kernel.org>
2019-05-29doc: kernel-parameters.txt: fix documentation of nmi_watchdog parameterZhenzhong Duan
The default behavior of hardlockup depends on the config of CONFIG_BOOTPARAM_HARDLOCKUP_PANIC. Fix the description of nmi_watchdog to make it clear. Suggested-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com> Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org> Acked-by: Ingo Molnar <mingo@kernel.org> Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Kees Cook <keescook@chromium.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: linux-doc@vger.kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-25rcu: Enable elimination of Tree-RCU softirq processingSebastian Andrzej Siewior
Some workloads need to change kthread priority for RCU core processing without affecting other softirq work. This commit therefore introduces the rcutree.use_softirq kernel boot parameter, which moves the RCU core work from softirq to a per-CPU SCHED_OTHER kthread named rcuc. Use of SCHED_OTHER approach avoids the scalability problems that appeared with the earlier attempt to move RCU core processing to from softirq to kthreads. That said, kernels built with RCU_BOOST=y will run the rcuc kthreads at the RCU-boosting priority. Note that rcutree.use_softirq=0 must be specified to move RCU core processing to the rcuc kthreads: rcutree.use_softirq=1 is the default. Reported-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Mike Galbraith <efault@gmx.de> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> [ paulmck: Adjust for invoke_rcu_callbacks() only ever being invoked from RCU core processing, in contrast to softirq->rcuc transition in old mainline RCU priority boosting. ] [ paulmck: Avoid wakeups when scheduler might have invoked rcu_read_unlock() while holding rq or pi locks, also possibly fixing a pre-existing latent bug involving raise_softirq()-induced wakeups. ] Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-05-23docs: fix numaperf.rst and add it to the doc treeJonathan Corbet
Commit 13bac55ef7ae ("doc/mm: New documentation for memory performance") added numaperf.rst, but did not add it to the TOC tree. There was also an incorrectly marked literal block leading to this warning sequence: numaperf.rst:24: WARNING: Unexpected indentation. numaperf.rst:24: WARNING: Inline substitution_reference start-string without end-string. numaperf.rst:25: WARNING: Block quote ends without a blank line; unexpected unindent. Fix the block and add the file to the document tree. Fixes: 13bac55ef7ae ("doc/mm: New documentation for memory performance") Cc: Keith Busch <keith.busch@intel.com> Reviewed-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-18panic: add an option to replay all the printk message in bufferFeng Tang
Currently on panic, kernel will lower the loglevel and print out pending printk msg only with console_flush_on_panic(). Add an option for users to configure the "panic_print" to replay all dmesg in buffer, some of which they may have never seen due to the loglevel setting, which will help panic debugging . [feng.tang@intel.com: keep the original console_flush_on_panic() inside panic()] Link: http://lkml.kernel.org/r/1556199137-14163-1-git-send-email-feng.tang@intel.com [feng.tang@intel.com: use logbuf lock to protect the console log index] Link: http://lkml.kernel.org/r/1556269868-22654-1-git-send-email-feng.tang@intel.com Link: http://lkml.kernel.org/r/1556095872-36838-1-git-send-email-feng.tang@intel.com Signed-off-by: Feng Tang <feng.tang@intel.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Cc: Aaro Koskinen <aaro.koskinen@nokia.com> Cc: Petr Mladek <pmladek@suse.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: Kees Cook <keescook@chromium.org> Cc: Borislav Petkov <bp@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-15Merge tag 'for-linus-5.2b-rc1-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen updates from Juergen Gross: - some minor cleanups - two small corrections for Xen on ARM - two fixes for Xen PVH guest support - a patch for a new command line option to tune virtual timer handling * tag 'for-linus-5.2b-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen/arm: Use p2m entry with lock protection xen/arm: Free p2m entry if fail to add it to RB tree xen/pvh: correctly setup the PV EFI interface for dom0 xen/pvh: set xen_domain_type to HVM in xen_pvh_init xenbus: drop useless LIST_HEAD in xenbus_write_watch() and xenbus_file_write() xen-netfront: mark expected switch fall-through xen: xen-pciback: fix warning Using plain integer as NULL pointer x86/xen: Add "xen_timer_slop" command line option
2019-05-14ipc: allow boot time extension of IPCMNI from 32k to 16MWaiman Long
The maximum number of unique System V IPC identifiers was limited to 32k. That limit should be big enough for most use cases. However, there are some users out there requesting for more, especially those that are migrating from Solaris which uses 24 bits for unique identifiers. To satisfy the need of those users, a new boot time kernel option "ipcmni_extend" is added to extend the IPCMNI value to 16M. This is a 512X increase which should be big enough for users out there that need a large number of unique IPC identifier. The use of this new option will change the pattern of the IPC identifiers returned by functions like shmget(2). An application that depends on such pattern may not work properly. So it should only be used if the users really need more than 32k of unique IPC numbers. This new option does have the side effect of reducing the maximum number of unique sequence numbers from 64k down to 128. So it is a trade-off. The computation of a new IPC id is not done in the performance critical path. So a little bit of additional overhead shouldn't have any real performance impact. Link: http://lkml.kernel.org/r/20190329204930.21620-1-longman@redhat.com Signed-off-by: Waiman Long <longman@redhat.com> Acked-by: Manfred Spraul <manfred@colorfullife.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Davidlohr Bueso <dbueso@suse.de> Cc: "Eric W . Biederman" <ebiederm@xmission.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kees Cook <keescook@chromium.org> Cc: "Luis R. Rodriguez" <mcgrof@kernel.org> Cc: Matthew Wilcox <willy@infradead.org> Cc: Takashi Iwai <tiwai@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14panic/reboot: allow specifying reboot_mode for panic onlyAaro Koskinen
Allow specifying reboot_mode for panic only. This is needed on systems where ramoops is used to store panic logs, and user wants to use warm reset to preserve those, while still having cold reset on normal reboots. Link: http://lkml.kernel.org/r/20190322004735.27702-1-aaro.koskinen@iki.fi Signed-off-by: Aaro Koskinen <aaro.koskinen@nokia.com> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14mm: shuffle initial free memory to improve memory-side-cache utilizationDan Williams
Patch series "mm: Randomize free memory", v10. This patch (of 3): Randomization of the page allocator improves the average utilization of a direct-mapped memory-side-cache. Memory side caching is a platform capability that Linux has been previously exposed to in HPC (high-performance computing) environments on specialty platforms. In that instance it was a smaller pool of high-bandwidth-memory relative to higher-capacity / lower-bandwidth DRAM. Now, this capability is going to be found on general purpose server platforms where DRAM is a cache in front of higher latency persistent memory [1]. Robert offered an explanation of the state of the art of Linux interactions with memory-side-caches [2], and I copy it here: It's been a problem in the HPC space: http://www.nersc.gov/research-and-development/knl-cache-mode-performance-coe/ A kernel module called zonesort is available to try to help: https://software.intel.com/en-us/articles/xeon-phi-software and this abandoned patch series proposed that for the kernel: https://lkml.kernel.org/r/20170823100205.17311-1-lukasz.daniluk@intel.com Dan's patch series doesn't attempt to ensure buffers won't conflict, but also reduces the chance that the buffers will. This will make performance more consistent, albeit slower than "optimal" (which is near impossible to attain in a general-purpose kernel). That's better than forcing users to deploy remedies like: "To eliminate this gradual degradation, we have added a Stream measurement to the Node Health Check that follows each job; nodes are rebooted whenever their measured memory bandwidth falls below 300 GB/s." A replacement for zonesort was merged upstream in commit cc9aec03e58f ("x86/numa_emulation: Introduce uniform split capability"). With this numa_emulation capability, memory can be split into cache sized ("near-memory" sized) numa nodes. A bind operation to such a node, and disabling workloads on other nodes, enables full cache performance. However, once the workload exceeds the cache size then cache conflicts are unavoidable. While HPC environments might be able to tolerate time-scheduling of cache sized workloads, for general purpose server platforms, the oversubscribed cache case will be the common case. The worst case scenario is that a server system owner benchmarks a workload at boot with an un-contended cache only to see that performance degrade over time, even below the average cache performance due to excessive conflicts. Randomization clips the peaks and fills in the valleys of cache utilization to yield steady average performance. Here are some performance impact details of the patches: 1/ An Intel internal synthetic memory bandwidth measurement tool, saw a 3X speedup in a contrived case that tries to force cache conflicts. The contrived cased used the numa_emulation capability to force an instance of the benchmark to be run in two of the near-memory sized numa nodes. If both instances were placed on the same emulated they would fit and cause zero conflicts. While on separate emulated nodes without randomization they underutilized the cache and conflicted unnecessarily due to the in-order allocation per node. 2/ A well known Java server application benchmark was run with a heap size that exceeded cache size by 3X. The cache conflict rate was 8% for the first run and degraded to 21% after page allocator aging. With randomization enabled the rate levelled out at 11%. 3/ A MongoDB workload did not observe measurable difference in cache-conflict rates, but the overall throughput dropped by 7% with randomization in one case. 4/ Mel Gorman ran his suite of performance workloads with randomization enabled on platforms without a memory-side-cache and saw a mix of some improvements and some losses [3]. While there is potentially significant improvement for applications that depend on low latency access across a wide working-set, the performance may be negligible to negative for other workloads. For this reason the shuffle capability defaults to off unless a direct-mapped memory-side-cache is detected. Even then, the page_alloc.shuffle=0 parameter can be specified to disable the randomization on those systems. Outside of memory-side-cache utilization concerns there is potentially security benefit from randomization. Some data exfiltration and return-oriented-programming attacks rely on the ability to infer the location of sensitive data objects. The kernel page allocator, especially early in system boot, has predictable first-in-first out behavior for physical pages. Pages are freed in physical address order when first onlined. Quoting Kees: "While we already have a base-address randomization (CONFIG_RANDOMIZE_MEMORY), attacks against the same hardware and memory layouts would certainly be using the predictability of allocation ordering (i.e. for attacks where the base address isn't important: only the relative positions between allocated memory). This is common in lots of heap-style attacks. They try to gain control over ordering by spraying allocations, etc. I'd really like to see this because it gives us something similar to CONFIG_SLAB_FREELIST_RANDOM but for the page allocator." While SLAB_FREELIST_RANDOM reduces the predictability of some local slab caches it leaves vast bulk of memory to be predictably in order allocated. However, it should be noted, the concrete security benefits are hard to quantify, and no known CVE is mitigated by this randomization. Introduce shuffle_free_memory(), and its helper shuffle_zone(), to perform a Fisher-Yates shuffle of the page allocator 'free_area' lists when they are initially populated with free memory at boot and at hotplug time. Do this based on either the presence of a page_alloc.shuffle=Y command line parameter, or autodetection of a memory-side-cache (to be added in a follow-on patch). The shuffling is done in terms of CONFIG_SHUFFLE_PAGE_ORDER sized free pages where the default CONFIG_SHUFFLE_PAGE_ORDER is MAX_ORDER-1 i.e. 10, 4MB this trades off randomization granularity for time spent shuffling. MAX_ORDER-1 was chosen to be minimally invasive to the page allocator while still showing memory-side cache behavior improvements, and the expectation that the security implications of finer granularity randomization is mitigated by CONFIG_SLAB_FREELIST_RANDOM. The performance impact of the shuffling appears to be in the noise compared to other memory initialization work. This initial randomization can be undone over time so a follow-on patch is introduced to inject entropy on page free decisions. It is reasonable to ask if the page free entropy is sufficient, but it is not enough due to the in-order initial freeing of pages. At the start of that process putting page1 in front or behind page0 still keeps them close together, page2 is still near page1 and has a high chance of being adjacent. As more pages are added ordering diversity improves, but there is still high page locality for the low address pages and this leads to no significant impact to the cache conflict rate. [1]: https://itpeernetwork.intel.com/intel-optane-dc-persistent-memory-operating-modes/ [2]: https://lkml.kernel.org/r/AT5PR8401MB1169D656C8B5E121752FC0F8AB120@AT5PR8401MB1169.NAMPRD84.PROD.OUTLOOK.COM [3]: https://lkml.org/lkml/2018/10/12/309 [dan.j.williams@intel.com: fix shuffle enable] Link: http://lkml.kernel.org/r/154943713038.3858443.4125180191382062871.stgit@dwillia2-desk3.amr.corp.intel.com [cai@lca.pw: fix SHUFFLE_PAGE_ALLOCATOR help texts] Link: http://lkml.kernel.org/r/20190425201300.75650-1-cai@lca.pw Link: http://lkml.kernel.org/r/154899811738.3165233.12325692939590944259.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Qian Cai <cai@lca.pw> Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Keith Busch <keith.busch@intel.com> Cc: Robert Elliott <elliott@hpe.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14Merge branch 'x86-mds-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 MDS mitigations from Thomas Gleixner: "Microarchitectural Data Sampling (MDS) is a hardware vulnerability which allows unprivileged speculative access to data which is available in various CPU internal buffers. This new set of misfeatures has the following CVEs assigned: CVE-2018-12126 MSBDS Microarchitectural Store Buffer Data Sampling CVE-2018-12130 MFBDS Microarchitectural Fill Buffer Data Sampling CVE-2018-12127 MLPDS Microarchitectural Load Port Data Sampling CVE-2019-11091 MDSUM Microarchitectural Data Sampling Uncacheable Memory MDS attacks target microarchitectural buffers which speculatively forward data under certain conditions. Disclosure gadgets can expose this data via cache side channels. Contrary to other speculation based vulnerabilities the MDS vulnerability does not allow the attacker to control the memory target address. As a consequence the attacks are purely sampling based, but as demonstrated with the TLBleed attack samples can be postprocessed successfully. The mitigation is to flush the microarchitectural buffers on return to user space and before entering a VM. It's bolted on the VERW instruction and requires a microcode update. As some of the attacks exploit data structures shared between hyperthreads, full protection requires to disable hyperthreading. The kernel does not do that by default to avoid breaking unattended updates. The mitigation set comes with documentation for administrators and a deeper technical view" * 'x86-mds-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits) x86/speculation/mds: Fix documentation typo Documentation: Correct the possible MDS sysfs values x86/mds: Add MDSUM variant to the MDS documentation x86/speculation/mds: Add 'mitigations=' support for MDS x86/speculation/mds: Print SMT vulnerable on MSBDS with mitigations off x86/speculation/mds: Fix comment x86/speculation/mds: Add SMT warning message x86/speculation: Move arch_smt_update() call to after mitigation decisions x86/speculation/mds: Add mds=full,nosmt cmdline option Documentation: Add MDS vulnerability documentation Documentation: Move L1TF to separate directory x86/speculation/mds: Add mitigation mode VMWERV x86/speculation/mds: Add sysfs reporting for MDS x86/speculation/mds: Add mitigation control for MDS x86/speculation/mds: Conditionally clear CPU buffers on idle entry x86/kvm/vmx: Add MDS protection when L1D Flush is not active x86/speculation/mds: Clear CPU buffers on exit to user x86/speculation/mds: Add mds_clear_cpu_buffers() x86/kvm: Expose X86_FEATURE_MD_CLEAR to guests x86/speculation/mds: Add BUG_MSBDS_ONLY ...
2019-05-10Merge tag 'powerpc-5.2-1' of ↵Linus Torvalds
ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: "Slightly delayed due to the issue with printk() calling probe_kernel_read() interacting with our new user access prevention stuff, but all fixed now. The only out-of-area changes are the addition of a cpuhp_state, small additions to Documentation and MAINTAINERS updates. Highlights: - Support for Kernel Userspace Access/Execution Prevention (like SMAP/SMEP/PAN/PXN) on some 64-bit and 32-bit CPUs. This prevents the kernel from accidentally accessing userspace outside copy_to/from_user(), or ever executing userspace. - KASAN support on 32-bit. - Rework of where we map the kernel, vmalloc, etc. on 64-bit hash to use the same address ranges we use with the Radix MMU. - A rewrite into C of large parts of our idle handling code for 64-bit Book3S (ie. power8 & power9). - A fast path entry for syscalls on 32-bit CPUs, for a 12-17% speedup in the null_syscall benchmark. - On 64-bit bare metal we have support for recovering from errors with the time base (our clocksource), however if that fails currently we hang in __delay() and never crash. We now have support for detecting that case and short circuiting __delay() so we at least panic() and reboot. - Add support for optionally enabling the DAWR on Power9, which had to be disabled by default due to a hardware erratum. This has the effect of enabling hardware breakpoints for GDB, the downside is a badly behaved program could crash the machine by pointing the DAWR at cache inhibited memory. This is opt-in obviously. - xmon, our crash handler, gets support for a read only mode where operations that could change memory or otherwise disturb the system are disabled. Plus many clean-ups, reworks and minor fixes etc. Thanks to: Christophe Leroy, Akshay Adiga, Alastair D'Silva, Alexey Kardashevskiy, Andrew Donnellan, Aneesh Kumar K.V, Anju T Sudhakar, Anton Blanchard, Ben Hutchings, Bo YU, Breno Leitao, Cédric Le Goater, Christopher M. Riedl, Christoph Hellwig, Colin Ian King, David Gibson, Ganesh Goudar, Gautham R. Shenoy, George Spelvin, Greg Kroah-Hartman, Greg Kurz, Horia Geantă, Jagadeesh Pagadala, Joel Stanley, Joe Perches, Julia Lawall, Laurentiu Tudor, Laurent Vivier, Lukas Bulwahn, Madhavan Srinivasan, Mahesh Salgaonkar, Mathieu Malaterre, Michael Neuling, Mukesh Ojha, Nathan Fontenot, Nathan Lynch, Nicholas Piggin, Nick Desaulniers, Oliver O'Halloran, Peng Hao, Qian Cai, Ravi Bangoria, Rick Lindsley, Russell Currey, Sachin Sant, Stewart Smith, Sukadev Bhattiprolu, Thomas Huth, Tobin C. Harding, Tyrel Datwyler, Valentin Schneider, Wei Yongjun, Wen Yang, YueHaibing" * tag 'powerpc-5.2-1' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (205 commits) powerpc/64s: Use early_mmu_has_feature() in set_kuap() powerpc/book3s/64: check for NULL pointer in pgd_alloc() powerpc/mm: Fix hugetlb page initialization ocxl: Fix return value check in afu_ioctl() powerpc/mm: fix section mismatch for setup_kup() powerpc/mm: fix redundant inclusion of pgtable-frag.o in Makefile powerpc/mm: Fix makefile for KASAN powerpc/kasan: add missing/lost Makefile selftests/powerpc: Add a signal fuzzer selftest powerpc/booke64: set RI in default MSR ocxl: Provide global MMIO accessors for external drivers ocxl: move event_fd handling to frontend ocxl: afu_irq only deals with IRQ IDs, not offsets ocxl: Allow external drivers to use OpenCAPI contexts ocxl: Create a clear delineation between ocxl backend & frontend ocxl: Don't pass pci_dev around ocxl: Split pci.c ocxl: Remove some unused exported symbols ocxl: Remove superfluous 'extern' from headers ocxl: read_pasid never returns an error, so make it void ...
2019-05-09Merge branch 'for-5.2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup Pull cgroup updates from Tejun Heo: "This includes Roman's cgroup2 freezer implementation. It's a separate machanism from cgroup1 freezer. Instead of blocking user tasks in arbitrary uninterruptible sleeps, the new implementation extends jobctl stop - frozen tasks are trapped in jobctl stop until thawed and can be killed and ptraced. Lots of thanks to Oleg for sheperding the effort. Other than that, there are a few trivial changes" * 'for-5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: cgroup: never call do_group_exit() with task->frozen bit set kernel: cgroup: fix misuse of %x cgroup: get rid of cgroup_freezer_frozen_exit() cgroup: prevent spurious transition into non-frozen state cgroup: Remove unused cgrp variable cgroup: document cgroup v2 freezer interface cgroup: add tracing points for cgroup v2 freezer cgroup: make TRACE_CGROUP_PATH irq-safe kselftests: cgroup: add freezer controller self-tests kselftests: cgroup: don't fail on cg_kill_all() error in cg_destroy() cgroup: cgroup v2 freezer cgroup: protect cgroup->nr_(dying_)descendants by css_set_lock cgroup: implement __cgroup_task_count() helper cgroup: rename freezer.c into legacy_freezer.c cgroup: remove extra cgroup_migrate_finish() call
2019-05-09Merge branch 'next-integrity' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security Pull intgrity updates from James Morris: "This contains just three patches, the remainder were either included in other pull requests (eg. audit, lockdown) or will be upstreamed via other subsystems (eg. kselftests, Power). Included here is one bug fix, one documentation update, and extending the x86 IMA arch policy rules to coordinate the different kernel module signature verification methods" * 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: doc/kernel-parameters.txt: Deprecate ima_appraise_tcb x86/ima: add missing include x86/ima: require signed kernel modules
2019-05-08Documentation: Correct the possible MDS sysfs valuesTyler Hicks
Adjust the last two rows in the table that display possible values when MDS mitigation is enabled. They both were slightly innacurate. In addition, convert the table of possible values and their descriptions to a list-table. The simple table format uses the top border of equals signs to determine cell width which resulted in the first column being far too wide in comparison to the second column that contained the majority of the text. Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2019-05-08x86/mds: Add MDSUM variant to the MDS documentationspeck for Pawan Gupta
Updated the documentation for a new CVE-2019-11091 Microarchitectural Data Sampling Uncacheable Memory (MDSUM) which is a variant of Microarchitectural Data Sampling (MDS). MDS is a family of side channel attacks on internal buffers in Intel CPUs. MDSUM is a special case of MSBDS, MFBDS and MLPDS. An uncacheable load from memory that takes a fault or assist can leave data in a microarchitectural structure that may later be observed using one of the same methods used by MSBDS, MFBDS or MLPDS. There are no new code changes expected for MDSUM. The existing mitigation for MDS applies to MDSUM as well. Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Tyler Hicks <tyhicks@canonical.com> Reviewed-by: Jon Masters <jcm@redhat.com>
2019-05-07Merge tag 'ext4_for_linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 updates from Ted Ts'o: "Add as a feature case-insensitive directories (the casefold feature) using Unicode 12.1. Also, the usual largish number of cleanups and bug fixes" * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (25 commits) ext4: export /sys/fs/ext4/feature/casefold if Unicode support is present ext4: fix ext4_show_options for file systems w/o journal unicode: refactor the rule for regenerating utf8data.h docs: ext4.rst: document case-insensitive directories ext4: Support case-insensitive file name lookups ext4: include charset encoding information in the superblock MAINTAINERS: add Unicode subsystem entry unicode: update unicode database unicode version 12.1.0 unicode: introduce test module for normalized utf8 implementation unicode: implement higher level API for string handling unicode: reduce the size of utf8data[] unicode: introduce code for UTF-8 normalization unicode: introduce UTF-8 character database ext4: actually request zeroing of inode table after grow ext4: cond_resched in work-heavy group loops ext4: fix use-after-free race with debug_want_extra_isize ext4: avoid drop reference to iloc.bh twice ext4: ignore e_value_offs for xattrs with value-in-ea-inode ext4: protect journal inode's blocks using block_validity ext4: use BUG() instead of BUG_ON(1) ...
2019-05-07Merge tag 'driver-core-5.2-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core/kobject updates from Greg KH: "Here is the "big" set of driver core patches for 5.2-rc1 There are a number of ACPI patches in here as well, as Rafael said they should go through this tree due to the driver core changes they required. They have all been acked by the ACPI developers. There are also a number of small subsystem-specific changes in here, due to some changes to the kobject core code. Those too have all been acked by the various subsystem maintainers. As for content, it's pretty boring outside of the ACPI changes: - spdx cleanups - kobject documentation updates - default attribute groups for kobjects - other minor kobject/driver core fixes All have been in linux-next for a while with no reported issues" * tag 'driver-core-5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (47 commits) kobject: clean up the kobject add documentation a bit more kobject: Fix kernel-doc comment first line kobject: Remove docstring reference to kset firmware_loader: Fix a typo ("syfs" -> "sysfs") kobject: fix dereference before null check on kobj Revert "driver core: platform: Fix the usage of platform device name(pdev->name)" init/config: Do not select BUILD_BIN2C for IKCONFIG Provide in-kernel headers to make extending kernel easier kobject: Improve doc clarity kobject_init_and_add() kobject: Improve docs for kobject_add/del driver core: platform: Fix the usage of platform device name(pdev->name) livepatch: Replace klp_ktype_patch's default_attrs with groups cpufreq: schedutil: Replace default_attrs field with groups padata: Replace padata_attr_type default_attrs field with groups irqdesc: Replace irq_kobj_type's default_attrs field with groups net-sysfs: Replace ktype default_attrs field with groups block: Replace all ktype default_attrs with groups samples/kobject: Replace foo_ktype's default_attrs field with groups kobject: Add support for default attribute groups to kobj_type driver core: Postpone DMA tear-down until after devres release for probe failure ...
2019-05-06Merge tag 'pm-5.2-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management updates from Rafael Wysocki: "These fix the (Intel-specific) Performance and Energy Bias Hint (EPB) handling and expose it to user space via sysfs, fix and clean up several cpufreq drivers, add support for two new chips to the qoriq cpufreq driver, fix, simplify and clean up the cpufreq core and the schedutil governor, add support for "CPU" domains to the generic power domains (genpd) framework and provide low-level PSCI firmware support for that feature, fix the exynos cpuidle driver and fix a couple of issues in the devfreq subsystem and clean it up. Specifics: - Fix the handling of Performance and Energy Bias Hint (EPB) on Intel processors and expose it to user space via sysfs to avoid having to access it through the generic MSR I/F (Rafael Wysocki). - Improve the handling of global turbo changes made by the platform firmware in the intel_pstate driver (Rafael Wysocki). - Convert some slow-path static_cpu_has() callers to boot_cpu_has() in cpufreq (Borislav Petkov). - Fix the frequency calculation loop in the armada-37xx cpufreq driver (Gregory CLEMENT). - Fix possible object reference leaks in multuple cpufreq drivers (Wen Yang). - Fix kerneldoc comment in the centrino cpufreq driver (dongjian). - Clean up the ACPI and maple cpufreq drivers (Viresh Kumar, Mohan Kumar). - Add support for lx2160a and ls1028a to the qoriq cpufreq driver (Vabhav Sharma, Yuantian Tang). - Fix kobject memory leak in the cpufreq core (Viresh Kumar). - Simplify the IOwait boosting in the schedutil cpufreq governor and rework the TSC cpufreq notifier on x86 (Rafael Wysocki). - Clean up the cpufreq core and statistics code (Yue Hu, Kyle Lin). - Improve the cpufreq documentation, add SPDX license tags to some PM documentation files and unify copyright notices in them (Rafael Wysocki). - Add support for "CPU" domains to the generic power domains (genpd) framework and provide low-level PSCI firmware support for that feature (Ulf Hansson). - Rearrange the PSCI firmware support code and add support for SYSTEM_RESET2 to it (Ulf Hansson, Sudeep Holla). - Improve genpd support for devices in multiple power domains (Ulf Hansson). - Unify target residency for the AFTR and coupled AFTR states in the exynos cpuidle driver (Marek Szyprowski). - Introduce new helper routine in the operating performance points (OPP) framework (Andrew-sh.Cheng). - Add support for passing on-die termination (ODT) and auto power down parameters from the kernel to Trusted Firmware-A (TF-A) to the rk3399_dmc devfreq driver (Enric Balletbo i Serra). - Add tracing to devfreq (Lukasz Luba). - Make the exynos-bus devfreq driver suspend all devices on system shutdown (Marek Szyprowski). - Fix a few minor issues in the devfreq subsystem and clean it up somewhat (Enric Balletbo i Serra, MyungJoo Ham, Rob Herring, Saravana Kannan, Yangtao Li). - Improve system wakeup diagnostics (Stephen Boyd). - Rework filesystem sync messages emitted during system suspend and hibernation (Harry Pan)" * tag 'pm-5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (72 commits) cpufreq: Fix kobject memleak cpufreq: armada-37xx: fix frequency calculation for opp cpufreq: centrino: Fix centrino_setpolicy() kerneldoc comment cpufreq: qoriq: add support for lx2160a x86: tsc: Rework time_cpufreq_notifier() PM / Domains: Allow to attach a CPU via genpd_dev_pm_attach_by_id|name() PM / Domains: Search for the CPU device outside the genpd lock PM / Domains: Drop unused in-parameter to some genpd functions PM / Domains: Use the base device for driver_deferred_probe_check_state() cpufreq: qoriq: Add ls1028a chip support PM / Domains: Enable genpd_dev_pm_attach_by_id|name() for single PM domain PM / Domains: Allow OF lookup for multi PM domain case from ->attach_dev() PM / Domains: Don't kfree() the virtual device in the error path cpufreq: Move ->get callback check outside of __cpufreq_get() PM / Domains: remove unnecessary unlikely() cpufreq: Remove needless bios_limit check in show_bios_limit() drivers/cpufreq/acpi-cpufreq.c: This fixes the following checkpatch warning firmware/psci: add support for SYSTEM_RESET2 PM / devfreq: add tracing for scheduling work trace: events: add devfreq trace event file ...
2019-05-06Merge tag 'acpi-5.2-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull ACPI updates from Rafael Wysocki: "These rearrange the ACPI documentation by converting it to the .rst format and splitting it into clear categories (admin guide, driver API, firmware guide), switch over multiple users of a problematic library function to a new better one, update the ACPICA code in the kernel to a new upstream release, fix a few issues, improve power device management diagnostics and do some cleanups. Specifics: - Convert the ACPI documentation in the kernel source tree to the .rst format and split it into the admin guide, driver API and firmware guide parts (Changbin Du). - Add a PRP0001 usage example to the ACPI documentation (Thomas Preston). - Switch over the users of the acpi_dev_get_first_match_name() library function which turned out to be problematic to a new, better one called acpi_dev_get_first_match_dev() (Andy Shevchenko, YueHaibing). - Update the ACPICA code in the kernel to upstream release 20190405 including: * Null pointer dereference check in acpi_ns_delete_node() (Erik Schmauss). * Multiple macro and function name changes (Bob Moore). * Predefined operation region name fix (Erik Schmauss). - Fix hibernation issue on systems using the Baytrail and Cherrytrail Intel SoCs introduced during the 4.20 development cycle (Hans de Goede). - Add Sony VPCEH3U1E to the backlight quirk list (Zhang Rui). - Fix button handling during system resume (Zhang Rui). - Add a device PM diagnostic message (Rafael Wysocki). - Clean up the code, comments and white space in multiple places (Bjorn Helgaas, Gustavo Silva, Kefeng Wang)" * tag 'acpi-5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (53 commits) Documentation: ACPI: move video_extension.txt to firmware-guide/acpi and convert to reST Documentation: ACPI: move ssdt-overlays.txt to admin-guide/acpi and convert to reST Documentation: ACPI: move lpit.txt to firmware-guide/acpi and convert to reST Documentation: ACPI: move cppc_sysfs.txt to admin-guide/acpi and convert to reST Documentation: ACPI: move apei/einj.txt to firmware-guide/acpi and convert to reST Documentation: ACPI: move apei/output_format.txt to firmware-guide/acpi and convert to reST Documentation: ACPI: move aml-debugger.txt to firmware-guide/acpi and convert to reST Documentation: ACPI: move method-tracing.txt to firmware-guide/acpi and convert to rsST Documentation: ACPI: move debug.txt to firmware-guide/acpi and convert to reST Documentation: ACPI: move dsd/data-node-references.txt to firmware-guide/acpi and convert to reST Documentation: ACPI: move dsd/graph.txt to firmware-guide/acpi and convert to reST Documentation: ACPI: move acpi-lid.txt to firmware-guide/acpi and convert to reST Documentation: ACPI: move i2c-muxes.txt to firmware-guide/acpi and convert to reST Documentation: ACPI: move dsdt-override.txt to admin-guide/acpi and convert to reST Documentation: ACPI: move initrd_table_override.txt to admin-guide/acpi and convert to reST Documentation: ACPI: move method-customizing.txt to firmware-guide/acpi and convert to reST Documentation: ACPI: move gpio-properties.txt to firmware-guide/acpi and convert to reST Documentation: ACPI: move DSD-properties-rules.txt to firmware-guide/acpi and covert to reST Documentation: ACPI: move scan_handlers.txt to driver-api/acpi and convert to reST Documentation: ACPI: move linuxized-acpica.txt to driver-api/acpi and convert to reST ...
2019-05-06Merge tag 'arm64-upstream' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Will Deacon: "Mostly just incremental improvements here: - Introduce AT_HWCAP2 for advertising CPU features to userspace - Expose SVE2 availability to userspace - Support for "data cache clean to point of deep persistence" (DC PODP) - Honour "mitigations=off" on the cmdline and advertise status via sysfs - CPU timer erratum workaround (Neoverse-N1 #1188873) - Introduce perf PMU driver for the SMMUv3 performance counters - Add config option to disable the kuser helpers page for AArch32 tasks - Futex modifications to ensure liveness under contention - Rework debug exception handling to seperate kernel and user handlers - Non-critical fixes and cleanup" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (92 commits) Documentation: Add ARM64 to kernel-parameters.rst arm64/speculation: Support 'mitigations=' cmdline option arm64: ssbs: Don't treat CPUs with SSBS as unaffected by SSB arm64: enable generic CPU vulnerabilites support arm64: add sysfs vulnerability show for speculative store bypass arm64: Fix size of __early_cpu_boot_status clocksource/arm_arch_timer: Use arch_timer_read_counter to access stable counters clocksource/arm_arch_timer: Remove use of workaround static key clocksource/arm_arch_timer: Drop use of static key in arch_timer_reg_read_stable clocksource/arm_arch_timer: Direcly assign set_next_event workaround arm64: Use arch_timer_read_counter instead of arch_counter_get_cntvct watchdog/sbsa: Use arch_timer_read_counter instead of arch_counter_get_cntvct ARM: vdso: Remove dependency with the arch_timer driver internals arm64: Apply ARM64_ERRATUM_1188873 to Neoverse-N1 arm64: Add part number for Neoverse N1 arm64: Make ARM64_ERRATUM_1188873 depend on COMPAT arm64: Restrict ARM64_ERRATUM_1188873 mitigation to AArch32 arm64: mm: Remove pte_unmap_nested() arm64: Fix compiler warning from pte_unmap() with -Wunused-but-set-variable arm64: compat: Reduce address limit for 64K pages ...
2019-05-06Merge tag 's390-5.2-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull s390 updates from Martin Schwidefsky: - Support for kernel address space layout randomization - Add support for kernel image signature verification - Convert s390 to the generic get_user_pages_fast code - Convert s390 to the stack unwind API analog to x86 - Add support for CPU directed interrupts for PCI devices - Provide support for MIO instructions to the PCI base layer, this will allow the use of direct PCI mappings in user space code - Add the basic KVM guest ultravisor interface for protected VMs - Add AT_HWCAP bits for several new hardware capabilities - Update the CPU measurement facility counter definitions to SVN 6 - Arnds cleanup patches for his quest to get LLVM compiles working - A vfio-ccw update with bug fixes and support for halt and clear - Improvements for the hardware TRNG code - Another round of cleanup for the QDIO layer - Numerous cleanups and bug fixes * tag 's390-5.2-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (98 commits) s390/vdso: drop unnecessary cc-ldoption s390: fix clang -Wpointer-sign warnigns in boot code s390: drop CONFIG_VIRT_TO_BUS s390: boot, purgatory: pass $(CLANG_FLAGS) where needed s390: only build for new CPUs with clang s390: simplify disabled_wait s390/ftrace: use HAVE_FUNCTION_GRAPH_RET_ADDR_PTR s390/unwind: introduce stack unwind API s390/opcodes: add missing instructions to the disassembler s390/bug: add entry size to the __bug_table section s390: use proper expoline sections for .dma code s390/nospec: rename assembler generated expoline thunks s390: add missing ENDPROC statements to assembler functions locking/lockdep: check for freed initmem in static_obj() s390/kernel: add support for kernel address space layout randomization (KASLR) s390/kernel: introduce .dma sections s390/sclp: do not use static sccbs s390/kprobes: use static buffer for insn_page s390/kernel: convert SYSCALL and PGM_CHECK handlers to .quad s390/kernel: build a relocatable kernel ...
2019-05-06Merge branch 'x86-timers-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 timer updates from Ingo Molnar: "Two changes: an LTO improvement, plus the new 'nowatchdog' boot option to disable the clocksource watchdog" * 'x86-timers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/timer: Don't inline __const_udelay() x86/tsc: Add option to disable tsc clocksource watchdog
2019-05-06Merge branch 'x86-kdump-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 kdump update from Ingo Molnar: "This includes two changes: - Raise the crash kernel reservation limit from from ~896MB to ~4GB. Only very old (and already known-broken) kexec-tools is supposed to be affected by this negatively. - Allow higher than 4GB crash kernel allocations when low allocations fail" * 'x86-kdump-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/kdump: Fall back to reserve high crashkernel memory x86/kdump: Have crashkernel=X reserve under 4G by default
2019-05-06Merge branch 'core-speculation-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull speculation mitigation update from Ingo Molnar: "This adds the "mitigations=" bootline option, which offers a cross-arch set of options that will work on x86, PowerPC and s390 that will map to the arch specific option internally" * 'core-speculation-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: s390/speculation: Support 'mitigations=' cmdline option powerpc/speculation: Support 'mitigations=' cmdline option x86/speculation: Support 'mitigations=' cmdline option cpu/speculation: Add 'mitigations=' cmdline option
2019-05-06Merge branches 'pm-docs' and 'pm-misc'Rafael J. Wysocki
* pm-docs: Documentation: PM: Unify copyright notices Documentation: PM: Add SPDX license tags to multiple files cpufreq: intel_pstate: Documentation: Add references sections * pm-misc: firmware/psci: add support for SYSTEM_RESET2 drivers: firmware: psci: Announce support for OS initiated suspend mode drivers: firmware: psci: Simplify error path of psci_dt_init() drivers: firmware: psci: Split psci_dt_cpu_init_idle() MAINTAINERS: Update files for PSCI drivers: firmware: psci: Move psci to separate directory
2019-05-01Documentation: Add ARM64 to kernel-parameters.rstJosh Poimboeuf
Add ARM64 to the legend of architectures. It's already used in several places in kernel-parameters.txt. Suggested-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-05-01arm64/speculation: Support 'mitigations=' cmdline optionJosh Poimboeuf
Configure arm64 runtime CPU speculation bug mitigations in accordance with the 'mitigations=' cmdline option. This affects Meltdown, Spectre v2, and Speculative Store Bypass. The default behavior is unchanged. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> [will: reorder checks so KASLR implies KPTI and SSBS is affected by cmdline] Signed-off-by: Will Deacon <will.deacon@arm.com>