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2018-08-05Merge 4.18-rc7 into master to pick up the KVM dependcyThomas Gleixner
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2018-08-02block: make iolatency avg_lat exponentially decayDennis Zhou (Facebook)
Currently, avg_lat is calculated by accumulating the mean of every window in a long running cumulative average. As time goes on, the metric becomes less and less useful due to the accumulated history. This patch reuses the same calculation done in load averages to make the avg_lat metric more lively. Unlike load averages, the avg only advances when a window elapses (due to an io). Idle periods extend the most recent window. Bucketing is used to limit the history of avg_lat by binding it to the window size. So, the window range for 1/exp (decay rate) is [1 min, 2.5 min) when windows elapse immediately. The current sample window size is exposed in the debug info to enable calculation of the window range. Signed-off-by: Dennis Zhou <dennisszhou@gmail.com> Acked-by: Tejun Heo <tj@kernel.org> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-07-30Merge 4.18-rc7 into driver-core-nextGreg Kroah-Hartman
We need the driver core changes in here as well for testing. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-27iommu: Add config option to set passthrough as defaultOlof Johansson
This allows the default behavior to be controlled by a kernel config option instead of changing the commandline for the kernel to include "iommu.passthrough=on" or "iommu=pt" on machines where this is desired. Likewise, for machines where this config option is enabled, it can be disabled at boot time with "iommu.passthrough=off" or "iommu=nopt". Also corrected iommu=pt documentation for IA-64, since it has no code that parses iommu= at all. Signed-off-by: Olof Johansson <olof@lixom.net> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2018-07-21vt: add /dev/vcsu* to devices.txtNicolas Pitre
Also mention that the traditional devices provide glyph values whereas /dev/vcsu* is unicode based. Suggested-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Nicolas Pitre <nico@linaro.org> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-20Documentation/l1tf: Fix typosTony Luck
Fix spelling and other typos Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2018-07-20x86/tsc: Redefine notsc to behave as tsc=unstablePavel Tatashin
Currently, the notsc kernel parameter disables the use of the TSC by sched_clock(). However, this parameter does not prevent the kernel from accessing tsc in other places. The only rationale to boot with notsc is to avoid timing discrepancies on multi-socket systems where TSC are not properly synchronized, and thus exclude TSC from being used for time keeping. But that prevents using TSC as sched_clock() as well, which is not necessary as the core sched_clock() implementation can handle non synchronized TSC based sched clocks just fine. However, there is another method to solve the above problem: booting with tsc=unstable parameter. This parameter allows sched_clock() to use TSC and just excludes it from timekeeping. So there is no real reason to keep notsc, but for compatibility reasons the parameter has to stay. Make it behave like 'tsc=unstable' instead. [ tglx: Massaged changelog ] Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Dou Liyang <douly.fnst@cn.fujitsu.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: steven.sistare@oracle.com Cc: daniel.m.jordan@oracle.com Cc: linux@armlinux.org.uk Cc: schwidefsky@de.ibm.com Cc: heiko.carstens@de.ibm.com Cc: john.stultz@linaro.org Cc: sboyd@codeaurora.org Cc: hpa@zytor.com Cc: peterz@infradead.org Cc: prarit@redhat.com Cc: feng.tang@intel.com Cc: pmladek@suse.com Cc: gnomes@lxorguk.ukuu.org.uk Cc: linux-s390@vger.kernel.org Cc: boris.ostrovsky@oracle.com Cc: jgross@suse.com Cc: pbonzini@redhat.com Link: https://lkml.kernel.org/r/20180719205545.16512-12-pasha.tatashin@oracle.com
2018-07-18blkcg: Track DISCARD statistics and output them in cgroup io.statTejun Heo
Add tracking of REQ_OP_DISCARD ios to the per-cgroup io.stat. Two fields, dbytes and dios, to respectively count the total bytes and number of discards are added. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Andy Newell <newella@fb.com> Cc: Michael Callahan <michaelcallahan@fb.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-07-17vsprintf: Add command line option debug_boot_weak_hashTobin C. Harding
Currently printing [hashed] pointers requires enough entropy to be available. Early in the boot sequence this may not be the case resulting in a dummy string '(____ptrval____)' being printed. This makes debugging the early boot sequence difficult. We can relax the requirement to use cryptographically secure hashing during debugging. This enables debugging while keeping development/production kernel behaviour the same. If new command line option debug_boot_weak_hash is enabled use cryptographically insecure hashing and hash pointer value immediately. Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Tobin C. Harding <me@tobin.cc> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2018-07-17Merge branch 'for-mingo' of ↵Ingo Molnar
git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu Pull RCU updates from Paul E. McKenney: - An optimization and a fix for RCU expedited grace periods, with the fix being from Boqun Feng. - Miscellaneous fixes, including a lockdep-annotation fix from Boqun Feng. - SRCU updates. - Updates to rcutorture and associated scripting. - Introduce grace-period sequence numbers to the RCU-bh, RCU-preempt, and RCU-sched flavors, replacing the old ->gpnum and ->completed pair of fields. This change allows lockless code to obtain the complete grace-period state with a single READ_ONCE(), which is needed to maintain tolerable lock contention during the upcoming consolidation of the three RCU flavors. Note that grace-period sequence numbers are already used by rcu_barrier(), expedited RCU grace periods, and SRCU, and are thus already heavily used and well-tested. Joel Fernandes contributed a number of excellent fixes and improvements. - Clean up some grace-period-reporting loose ends, including improving the handling of quiescent states from offline CPUs and fixing some false-positive WARN_ON_ONCE() invocations. (Strictly speaking, the WARN_ON_ONCE() invocations were quite correct, but their invariants were (harmlessly) violated by the earlier sloppy handling of quiescent states from offline CPUs.) In addition, improve grace-period forward-progress guarantees so as to allow removal of fail-safe checks that required otherwise needless lock acquisitions. Finally, add more diagnostics to help debug the upcoming consolidation of the RCU-bh, RCU-preempt, and RCU-sched flavors. - Additional miscellaneous fixes, including those contributed by Byungchul Park, Mauro Carvalho Chehab, Joe Perches, Joel Fernandes, Steven Rostedt, Andrea Parri, and Neil Brown. - Additional torture-test changes, including several contributed by Arnd Bergmann and Joel Fernandes. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-13Documentation: Add section about CPU vulnerabilitiesThomas Gleixner
Add documentation for the L1TF vulnerability and the mitigation mechanisms: - Explain the problem and risks - Document the mitigation mechanisms - Document the command line controls - Document the sysfs files Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lkml.kernel.org/r/20180713142323.287429944@linutronix.de
2018-07-13x86/bugs, kvm: Introduce boot-time control of L1TF mitigationsJiri Kosina
Introduce the 'l1tf=' kernel command line option to allow for boot-time switching of mitigation that is used on processors affected by L1TF. The possible values are: full Provides all available mitigations for the L1TF vulnerability. Disables SMT and enables all mitigations in the hypervisors. SMT control via /sys/devices/system/cpu/smt/control is still possible after boot. Hypervisors will issue a warning when the first VM is started in a potentially insecure configuration, i.e. SMT enabled or L1D flush disabled. full,force Same as 'full', but disables SMT control. Implies the 'nosmt=force' command line option. sysfs control of SMT and the hypervisor flush control is disabled. flush Leaves SMT enabled and enables the conditional hypervisor mitigation. Hypervisors will issue a warning when the first VM is started in a potentially insecure configuration, i.e. SMT enabled or L1D flush disabled. flush,nosmt Disables SMT and enables the conditional hypervisor mitigation. SMT control via /sys/devices/system/cpu/smt/control is still possible after boot. If SMT is reenabled or flushing disabled at runtime hypervisors will issue a warning. flush,nowarn Same as 'flush', but hypervisors will not warn when a VM is started in a potentially insecure configuration. off Disables hypervisor mitigations and doesn't emit any warnings. Default is 'flush'. Let KVM adhere to these semantics, which means: - 'lt1f=full,force' : Performe L1D flushes. No runtime control possible. - 'l1tf=full' - 'l1tf-flush' - 'l1tf=flush,nosmt' : Perform L1D flushes and warn on VM start if SMT has been runtime enabled or L1D flushing has been run-time enabled - 'l1tf=flush,nowarn' : Perform L1D flushes and no warnings are emitted. - 'l1tf=off' : L1D flushes are not performed and no warnings are emitted. KVM can always override the L1D flushing behavior using its 'vmentry_l1d_flush' module parameter except when lt1f=full,force is set. This makes KVM's private 'nosmt' option redundant, and as it is a bit non-systematic anyway (this is something to control globally, not on hypervisor level), remove that option. Add the missing Documentation entry for the l1tf vulnerability sysfs file while at it. Signed-off-by: Jiri Kosina <jkosina@suse.cz> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Jiri Kosina <jkosina@suse.cz> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Link: https://lkml.kernel.org/r/20180713142323.202758176@linutronix.de
2018-07-12rcutorture: Change units of onoff_interval to jiffiesPaul E. McKenney
Some RCU bugs have been sensitive to the frequency of CPU-hotplug operations, which have been gradually increased over time. But this frequency is now at the one-second lower limit that can be specified using the rcutorture.onoff_interval kernel parameter. This commit therefore changes the units of rcutorture.onoff_interval from seconds to jiffies, and also sets the value specified for this kernel parameter in the TREE03 rcutorture scenario to 200, which is 200 milliseconds for HZ=1000. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-07-10Documentation: Add powerpc options for spec_store_bypass_disableMichael Ellerman
Document the support for spec_store_bypass_disable that was added for powerpc in commit a048a07d7f45 ("powerpc/64s: Add support for a store forwarding barrier at kernel entry/exit"). Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-07-10docs: kernel-parameters.txt: document xhci-hcd.quirks parameterLaurentiu Tudor
This parameter introduced several years ago in the XHCI host controller driver was somehow left undocumented. Add a few lines in the kernel parameters text. Signed-off-by: Laurentiu Tudor <laurentiu.tudor@nxp.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-07-10driver core: allow stopping deferred probe after initRob Herring
Deferred probe will currently wait forever on dependent devices to probe, but sometimes a driver will never exist. It's also not always critical for a driver to exist. Platforms can rely on default configuration from the bootloader or reset defaults for things such as pinctrl and power domains. This is often the case with initial platform support until various drivers get enabled. There's at least 2 scenarios where deferred probe can render a platform broken. Both involve using a DT which has more devices and dependencies than the kernel supports. The 1st case is a driver may be disabled in the kernel config. The 2nd case is the kernel version may simply not have the dependent driver. This can happen if using a newer DT (provided by firmware perhaps) with a stable kernel version. Deferred probe issues can be difficult to debug especially if the console has dependencies or userspace fails to boot to a shell. There are also cases like IOMMUs where only built-in drivers are supported, so deferring probe after initcalls is not needed. The IOMMU subsystem implemented its own mechanism to handle this using OF_DECLARE linker sections. This commit adds makes ending deferred probe conditional on initcalls being completed or a debug timeout. Subsystems or drivers may opt-in by calling driver_deferred_probe_check_init_done() instead of unconditionally returning -EPROBE_DEFER. They may use additional information from DT or kernel's config to decide whether to continue to defer probe or not. The timeout mechanism is intended for debug purposes and WARNs loudly. The remaining deferred probe pending list will also be dumped after the timeout. Not that this timeout won't work for the console which needs to be enabled before userspace starts. However, if the console's dependencies are resolved, then the kernel log will be printed (as opposed to no output). Cc: Alexander Graf <agraf@suse.de> Signed-off-by: Rob Herring <robh@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-09Documentation: add a doc for blk-iolatencyJosef Bacik
A basic documentation to describe the interface, statistics, and behavior of io.latency. Signed-off-by: Josef Bacik <jbacik@fb.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-07-06docs: kernel-parameters.txt: document xhci-hcd.quirks parameterLaurentiu Tudor
This parameter introduced several years ago in the XHCI host controller driver was somehow left undocumented. Add a few lines in the kernel parameters text. Signed-off-by: Laurentiu Tudor <laurentiu.tudor@nxp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-04x86/KVM/VMX: Add module argument for L1TF mitigationKonrad Rzeszutek Wilk
Add a mitigation mode parameter "vmentry_l1d_flush" for CVE-2018-3620, aka L1 terminal fault. The valid arguments are: - "always" L1D cache flush on every VMENTER. - "cond" Conditional L1D cache flush, explained below - "never" Disable the L1D cache flush mitigation "cond" is trying to avoid L1D cache flushes on VMENTER if the code executed between VMEXIT and VMENTER is considered safe, i.e. is not bringing any interesting information into L1D which might exploited. [ tglx: Split out from a larger patch ] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2018-07-04x86/KVM: Warn user if KVM is loaded SMT and L1TF CPU bug being presentKonrad Rzeszutek Wilk
If the L1TF CPU bug is present we allow the KVM module to be loaded as the major of users that use Linux and KVM have trusted guests and do not want a broken setup. Cloud vendors are the ones that are uncomfortable with CVE 2018-3620 and as such they are the ones that should set nosmt to one. Setting 'nosmt' means that the system administrator also needs to disable SMT (Hyper-threading) in the BIOS, or via the 'nosmt' command line parameter, or via the /sys/devices/system/cpu/smt/control. See commit 05736e4ac13c ("cpu/hotplug: Provide knobs to control SMT"). Other mitigations are to use task affinity, cpu sets, interrupt binding, etc - anything to make sure that _only_ the same guests vCPUs are running on sibling threads. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2018-07-04usercopy: Allow boot cmdline disabling of hardeningChris von Recklinghausen
Enabling HARDENED_USERCOPY may cause measurable regressions in networking performance: up to 8% under UDP flood. I ran a small packet UDP flood using pktgen vs. a host b2b connected. On the receiver side the UDP packets are processed by a simple user space process that just reads and drops them: https://github.com/netoptimizer/network-testing/blob/master/src/udp_sink.c Not very useful from a functional PoV, but it helps to pin-point bottlenecks in the networking stack. When running a kernel with CONFIG_HARDENED_USERCOPY=y, I see a 5-8% regression in the receive tput, compared to the same kernel without this option enabled. With CONFIG_HARDENED_USERCOPY=y, perf shows ~6% of CPU time spent cumulatively in __check_object_size (~4%) and __virt_addr_valid (~2%). The call-chain is: __GI___libc_recvfrom entry_SYSCALL_64_after_hwframe do_syscall_64 __x64_sys_recvfrom __sys_recvfrom inet_recvmsg udp_recvmsg __check_object_size udp_recvmsg() actually calls copy_to_iter() (inlined) and the latters calls check_copy_size() (again, inlined). A generic distro may want to enable HARDENED_USERCOPY in their default kernel config, but at the same time, such distro may want to be able to avoid the performance penalties in with the default configuration and disable the stricter check on a per-boot basis. This change adds a boot parameter that conditionally disables HARDENED_USERCOPY via "hardened_usercopy=off". Signed-off-by: Chris von Recklinghausen <crecklin@redhat.com> Signed-off-by: Kees Cook <keescook@chromium.org>
2018-07-02Merge tag 'v4.18-rc3' into docs-nextJonathan Corbet
-rc1 broke the docs build due to changes in the e100/e1000 drivers; -rc3 got the fixes via the networking tree. Pull in -rc3 so that the docs tree can actually build the docs again.
2018-07-02Revert "x86/apic: Ignore secondary threads if nosmt=force"Thomas Gleixner
Dave Hansen reported, that it's outright dangerous to keep SMT siblings disabled completely so they are stuck in the BIOS and wait for SIPI. The reason is that Machine Check Exceptions are broadcasted to siblings and the soft disabled sibling has CR4.MCE = 0. If a MCE is delivered to a logical core with CR4.MCE = 0, it asserts IERR#, which shuts down or reboots the machine. The MCE chapter in the SDM contains the following blurb: Because the logical processors within a physical package are tightly coupled with respect to shared hardware resources, both logical processors are notified of machine check errors that occur within a given physical processor. If machine-check exceptions are enabled when a fatal error is reported, all the logical processors within a physical package are dispatched to the machine-check exception handler. If machine-check exceptions are disabled, the logical processors enter the shutdown state and assert the IERR# signal. When enabling machine-check exceptions, the MCE flag in control register CR4 should be set for each logical processor. Reverting the commit which ignores siblings at enumeration time solves only half of the problem. The core cpuhotplug logic needs to be adjusted as well. This thoughtful engineered mechanism also turns the boot process on all Intel HT enabled systems into a MCE lottery. MCE is enabled on the boot CPU before the secondary CPUs are brought up. Depending on the number of physical cores the window in which this situation can happen is smaller or larger. On a HSW-EX it's about 750ms: MCE is enabled on the boot CPU: [ 0.244017] mce: CPU supports 22 MCE banks The corresponding sibling #72 boots: [ 1.008005] .... node #0, CPUs: #72 That means if an MCE hits on physical core 0 (logical CPUs 0 and 72) between these two points the machine is going to shutdown. At least it's a known safe state. It's obvious that the early boot can be hit by an MCE as well and then runs into the same situation because MCEs are not yet enabled on the boot CPU. But after enabling them on the boot CPU, it does not make any sense to prevent the kernel from recovering. Adjust the nosmt kernel parameter documentation as well. Reverts: 2207def700f9 ("x86/apic: Ignore secondary threads if nosmt=force") Reported-by: Dave Hansen <dave.hansen@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Tony Luck <tony.luck@intel.com>
2018-06-29PCI: Make early dump functionality genericSinan Kaya
Move early dump functionality into common code so that it is available for all architectures. No need to carry arch-specific reads around as the read hooks are already initialized by the time pci_setup_device() is getting called during scan. Tested-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Sinan Kaya <okaya@codeaurora.org> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
2018-06-29Documentation/admin-guide/README.rst: add a label for cross-referencingMichael Rodin
Add a label to the top of the file to allow cross-referencing. Currently it's not possible to cross-reference this file from Documentation/process/howto.rst because of the missing label. Signed-off-by: Michael Rodin <michael-git@rodin.online> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-06-27Documentation: intel_pstate: Describe hwp_dynamic_boost sysfs knobRafael J. Wysocki
Document the recently introduced hwp_dynamic_boost sysfs knob allowing user space to tell intel_pstate to use iowait boosting in the active mode with HWP enabled (to improve performance). Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
2018-06-27Documentation: admin-guide: intel_pstate: Fix sysfs pathRafael J. Wysocki
Fix an incorrect sysfs path in the intel_pstate admin-guide documentation. Fixes: 33fc30b47098 (cpufreq: intel_pstate: Document the current behavior and user interface) Reported-by: Pawit Pornkitprasan <p.pawit@gmail.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-06-21cpu/hotplug: Provide knobs to control SMTThomas Gleixner
Provide a command line and a sysfs knob to control SMT. The command line options are: 'nosmt': Enumerate secondary threads, but do not online them 'nosmt=force': Ignore secondary threads completely during enumeration via MP table and ACPI/MADT. The sysfs control file has the following states (read/write): 'on': SMT is enabled. Secondary threads can be freely onlined 'off': SMT is disabled. Secondary threads, even if enumerated cannot be onlined 'forceoff': SMT is permanentely disabled. Writes to the control file are rejected. 'notsupported': SMT is not supported by the CPU The command line option 'nosmt' sets the sysfs control to 'off'. This can be changed to 'on' to reenable SMT during runtime. The command line option 'nosmt=force' sets the sysfs control to 'forceoff'. This cannot be changed during runtime. When SMT is 'on' and the control file is changed to 'off' then all online secondary threads are offlined and attempts to online a secondary thread later on are rejected. When SMT is 'off' and the control file is changed to 'on' then secondary threads can be onlined again. The 'off' -> 'on' transition does not automatically online the secondary threads. When the control file is set to 'forceoff', the behaviour is the same as setting it to 'off', but the operation is irreversible and later writes to the control file are rejected. When the control status is 'notsupported' then writes to the control file are rejected. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Acked-by: Ingo Molnar <mingo@kernel.org>
2018-06-21Documentation: intel_pstate: Fix typoRafael J. Wysocki
Fix a typo in the intel_pstate admin-guide documentation. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-06-15kernel-parameters.txt: fix pointers to sound parametersMauro Carvalho Chehab
The alsa parameters file was renamed to alsa-configuration.rst. With regards to OSS, it got retired as a hole by at changeset 727dede0ba8a ("sound: Retire OSS"). So, it doesn't make sense to keep mentioning it at kernel-parameters.txt. Fixes: 727dede0ba8a ("sound: Retire OSS") Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Acked-by: Jonathan Corbet <corbet@lwn.net>
2018-06-15docs: Fix some broken referencesMauro Carvalho Chehab
As we move stuff around, some doc references are broken. Fix some of them via this script: ./scripts/documentation-file-ref-check --fix Manually checked if the produced result is valid, removing a few false-positives. Acked-by: Takashi Iwai <tiwai@suse.de> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Acked-by: Stephen Boyd <sboyd@kernel.org> Acked-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com> Acked-by: Mathieu Poirier <mathieu.poirier@linaro.org> Reviewed-by: Coly Li <colyli@suse.de> Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Acked-by: Jonathan Corbet <corbet@lwn.net>
2018-06-14Merge tag 'apparmor-pr-2018-06-13' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor Pull AppArmor updates from John Johansen: "Features - add support for mapping secids and using secctxes - add the ability to get a task's secid - add support for audit rule filtering Cleanups: - multiple typo fixes - Convert to use match_string() helper - update git and wiki locations in AppArmor docs - improve get_buffers macro by using get_cpu_ptr - Use an IDR to allocate apparmor secids Bug fixes: - fix '*seclen' is never less than zero - fix mediation of prlimit - fix memory leak when deduping profile load - fix ptrace read check - fix memory leak of rule on error exit path" * tag 'apparmor-pr-2018-06-13' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor: (21 commits) apparmor: fix ptrace read check apparmor: fix memory leak when deduping profile load apparmor: fix mediation of prlimit apparmor: fixup secid map conversion to using IDR apparmor: Use an IDR to allocate apparmor secids apparmor: Fix memory leak of rule on error exit path apparmor: modify audit rule support to support profile stacks apparmor: Add support for audit rule filtering apparmor: update git and wiki locations in AppArmor docs apparmor: Convert to use match_string() helper apparmor: improve get_buffers macro by using get_cpu_ptr apparmor: fix '*seclen' is never less than zero apparmor: fix typo "preconfinement" apparmor: fix typo "independent" apparmor: fix typo "traverse" apparmor: fix typo "type" apparmor: fix typo "replace" apparmor: fix typo "comparison" apparmor: fix typo "loosen" apparmor: add the ability to get a task's secid ...
2018-06-08Merge tag 'arm64-upstream' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Catalin Marinas: "Apart from the core arm64 and perf changes, the Spectre v4 mitigation touches the arm KVM code and the ACPI PPTT support touches drivers/ (acpi and cacheinfo). I should have the maintainers' acks in place. Summary: - Spectre v4 mitigation (Speculative Store Bypass Disable) support for arm64 using SMC firmware call to set a hardware chicken bit - ACPI PPTT (Processor Properties Topology Table) parsing support and enable the feature for arm64 - Report signal frame size to user via auxv (AT_MINSIGSTKSZ). The primary motivation is Scalable Vector Extensions which requires more space on the signal frame than the currently defined MINSIGSTKSZ - ARM perf patches: allow building arm-cci as module, demote dev_warn() to dev_dbg() in arm-ccn event_init(), miscellaneous cleanups - cmpwait() WFE optimisation to avoid some spurious wakeups - L1_CACHE_BYTES reverted back to 64 (for performance reasons that have to do with some network allocations) while keeping ARCH_DMA_MINALIGN to 128. cache_line_size() returns the actual hardware Cache Writeback Granule - Turn LSE atomics on by default in Kconfig - Kernel fault reporting tidying - Some #include and miscellaneous cleanups" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (53 commits) arm64: Fix syscall restarting around signal suppressed by tracer arm64: topology: Avoid checking numa mask for scheduler MC selection ACPI / PPTT: fix build when CONFIG_ACPI_PPTT is not enabled arm64: cpu_errata: include required headers arm64: KVM: Move VCPU_WORKAROUND_2_FLAG macros to the top of the file arm64: signal: Report signal frame size to userspace via auxv arm64/sve: Thin out initialisation sanity-checks for sve_max_vl arm64: KVM: Add ARCH_WORKAROUND_2 discovery through ARCH_FEATURES_FUNC_ID arm64: KVM: Handle guest's ARCH_WORKAROUND_2 requests arm64: KVM: Add ARCH_WORKAROUND_2 support for guests arm64: KVM: Add HYP per-cpu accessors arm64: ssbd: Add prctl interface for per-thread mitigation arm64: ssbd: Introduce thread flag to control userspace mitigation arm64: ssbd: Restore mitigation status on CPU resume arm64: ssbd: Skip apply_ssbd if not using dynamic mitigation arm64: ssbd: Add global mitigation state accessor arm64: Add 'ssbd' command-line option arm64: Add ARCH_WORKAROUND_2 probing arm64: Add per-cpu infrastructure to call ARCH_WORKAROUND_2 arm64: Call ARCH_WORKAROUND_2 on transitions between EL0 and EL1 ...
2018-06-07Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge updates from Andrew Morton: - a few misc things - ocfs2 updates - v9fs updates - MM - procfs updates - lib/ updates - autofs updates * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (118 commits) autofs: small cleanup in autofs_getpath() autofs: clean up includes autofs: comment on selinux changes needed for module autoload autofs: update MAINTAINERS entry for autofs autofs: use autofs instead of autofs4 in documentation autofs: rename autofs documentation files autofs: create autofs Kconfig and Makefile autofs: delete fs/autofs4 source files autofs: update fs/autofs4/Makefile autofs: update fs/autofs4/Kconfig autofs: copy autofs4 to autofs autofs4: use autofs instead of autofs4 everywhere autofs4: merge auto_fs.h and auto_fs4.h fs/binfmt_misc.c: do not allow offset overflow checkpatch: improve patch recognition lib/ucs2_string.c: add MODULE_LICENSE() lib/mpi: headers cleanup lib/percpu_ida.c: use _irqsave() instead of local_irq_save() + spin_lock lib/idr.c: remove simple_ida_lock lib/bitmap.c: micro-optimization for __bitmap_complement() ...
2018-06-07mm: memcg: allow lowering memory.swap.max below the current usageTejun Heo
Currently an attempt to set swap.max into a value lower than the actual swap usage fails, which causes configuration problems as there's no way of lowering the configuration below the current usage short of turning off swap entirely. This makes swap.max difficult to use and allows delegatees to lock the delegator out of reducing swap allocation. This patch updates swap_max_write() so that the limit can be lowered below the current usage. It doesn't implement active reclaiming of swap entries for the following reasons. * mem_cgroup_swap_full() already tells the swap machinary to aggressively reclaim swap entries if the usage is above 50% of limit, so simply lowering the limit automatically triggers gradual reclaim. * Forcing back swapped out pages is likely to heavily impact the workload and mess up the working set. Given that swap usually is a lot less valuable and less scarce, letting the existing usage dissipate over time through the above gradual reclaim and as they're falted back in is likely the better behavior. Link: http://lkml.kernel.org/r/20180523185041.GR1718769@devbig577.frc2.facebook.com Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Roman Gushchin <guro@fb.com> Acked-by: Rik van Riel <riel@surriel.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Shaohua Li <shli@fb.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-06-07memcg: introduce memory.minRoman Gushchin
Memory controller implements the memory.low best-effort memory protection mechanism, which works perfectly in many cases and allows protecting working sets of important workloads from sudden reclaim. But its semantics has a significant limitation: it works only as long as there is a supply of reclaimable memory. This makes it pretty useless against any sort of slow memory leaks or memory usage increases. This is especially true for swapless systems. If swap is enabled, memory soft protection effectively postpones problems, allowing a leaking application to fill all swap area, which makes no sense. The only effective way to guarantee the memory protection in this case is to invoke the OOM killer. It's possible to handle this case in userspace by reacting on MEMCG_LOW events; but there is still a place for a fail-safe in-kernel mechanism to provide stronger guarantees. This patch introduces the memory.min interface for cgroup v2 memory controller. It works very similarly to memory.low (sharing the same hierarchical behavior), except that it's not disabled if there is no more reclaimable memory in the system. If cgroup is not populated, its memory.min is ignored, because otherwise even the OOM killer wouldn't be able to reclaim the protected memory, and the system can stall. [guro@fb.com: s/low/min/ in docs] Link: http://lkml.kernel.org/r/20180510130758.GA9129@castle.DHCP.thefacebook.com Link: http://lkml.kernel.org/r/20180509180734.GA4856@castle.DHCP.thefacebook.com Signed-off-by: Roman Gushchin <guro@fb.com> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-06-07mm/docs: describe memory.low refinementsRoman Gushchin
Refine cgroup v2 docs after latest memory.low changes. Link: http://lkml.kernel.org/r/20180405185921.4942-4-guro@fb.com Signed-off-by: Roman Gushchin <guro@fb.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-06-07mm, memcontrol: implement memory.swap.eventsTejun Heo
Add swap max and fail events so that userland can monitor and respond to running out of swap. I'm not too sure about the fail event. Right now, it's a bit confusing which stats / events are recursive and which aren't and also which ones reflect events which originate from a given cgroup and which targets the cgroup. No idea what the right long term solution is and it could just be that growing them organically is actually the only right thing to do. Link: http://lkml.kernel.org/r/20180416231151.GI1911913@devbig577.frc2.facebook.com Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: Roman Gushchin <guro@fb.com> Cc: Rik van Riel <riel@surriel.com> Cc: <linux-api@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-06-07Merge tag 'pci-v4.18-changes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci Pull PCI updates from Bjorn Helgaas: - unify AER decoding for native and ACPI CPER sources (Alexandru Gagniuc) - add TLP header info to AER tracepoint (Thomas Tai) - add generic pcie_wait_for_link() interface (Oza Pawandeep) - handle AER ERR_FATAL by removing and re-enumerating devices, as Downstream Port Containment does (Oza Pawandeep) - factor out common code between AER and DPC recovery (Oza Pawandeep) - stop triggering DPC for ERR_NONFATAL errors (Oza Pawandeep) - share ERR_FATAL recovery path between AER and DPC (Oza Pawandeep) - disable ASPM L1.2 substate if we don't have LTR (Bjorn Helgaas) - respect platform ownership of LTR (Bjorn Helgaas) - clear interrupt status in top half to avoid interrupt storm (Oza Pawandeep) - neaten pci=earlydump output (Andy Shevchenko) - avoid errors when extended config space inaccessible (Gilles Buloz) - prevent sysfs disable of device while driver attached (Christoph Hellwig) - use core interface to report PCIe link properties in bnx2x, bnxt_en, cxgb4, ixgbe (Bjorn Helgaas) - remove unused pcie_get_minimum_link() (Bjorn Helgaas) - fix use-before-set error in ibmphp (Dan Carpenter) - fix pciehp timeouts caused by Command Completed errata (Bjorn Helgaas) - fix refcounting in pnv_php hotplug (Julia Lawall) - clear pciehp Presence Detect and Data Link Layer Status Changed on resume so we don't miss hotplug events (Mika Westerberg) - only request pciehp control if we support it, so platform can use ACPI hotplug otherwise (Mika Westerberg) - convert SHPC to be builtin only (Mika Westerberg) - request SHPC control via _OSC if we support it (Mika Westerberg) - simplify SHPC handoff from firmware (Mika Westerberg) - fix an SHPC quirk that mistakenly included *all* AMD bridges as well as devices from any vendor with device ID 0x7458 (Bjorn Helgaas) - assign a bus number even to non-native hotplug bridges to leave space for acpiphp additions, to fix a common Thunderbolt xHCI hot-add failure (Mika Westerberg) - keep acpiphp from scanning native hotplug bridges, to fix common Thunderbolt hot-add failures (Mika Westerberg) - improve "partially hidden behind bridge" messages from core (Mika Westerberg) - add macros for PCIe Link Control 2 register (Frederick Lawler) - replace IB/hfi1 custom macros with PCI core versions (Frederick Lawler) - remove dead microblaze and xtensa code (Bjorn Helgaas) - use dev_printk() when possible in xtensa and mips (Bjorn Helgaas) - remove unused pcie_port_acpi_setup() and portdrv_acpi.c (Bjorn Helgaas) - add managed interface to get PCI host bridge resources from OF (Jan Kiszka) - add support for unbinding generic PCI host controller (Jan Kiszka) - fix memory leaks when unbinding generic PCI host controller (Jan Kiszka) - request legacy VGA framebuffer only for VGA devices to avoid false device conflicts (Bjorn Helgaas) - turn on PCI_COMMAND_IO & PCI_COMMAND_MEMORY in pci_enable_device() like everybody else, not in pcibios_fixup_bus() (Bjorn Helgaas) - add generic enable function for simple SR-IOV hardware (Alexander Duyck) - use generic SR-IOV enable for ena, nvme (Alexander Duyck) - add ACS quirk for Intel 7th & 8th Gen mobile (Alex Williamson) - add ACS quirk for Intel 300 series (Mika Westerberg) - enable register clock for Armada 7K/8K (Gregory CLEMENT) - reduce Keystone "link already up" log level (Fabio Estevam) - move private DT functions to drivers/pci/ (Rob Herring) - factor out dwc CONFIG_PCI Kconfig dependencies (Rob Herring) - add DesignWare support to the endpoint test driver (Gustavo Pimentel) - add DesignWare support for endpoint mode (Gustavo Pimentel) - use devm_ioremap_resource() instead of devm_ioremap() in dra7xx and artpec6 (Gustavo Pimentel) - fix Qualcomm bitwise NOT issue (Dan Carpenter) - add Qualcomm runtime PM support (Srinivas Kandagatla) - fix DesignWare enumeration below bridges (Koen Vandeputte) - use usleep() instead of mdelay() in endpoint test (Jia-Ju Bai) - add configfs entries for pci_epf_driver device IDs (Kishon Vijay Abraham I) - clean up pci_endpoint_test driver (Gustavo Pimentel) - update Layerscape maintainer email addresses (Minghuan Lian) - add COMPILE_TEST to improve build test coverage (Rob Herring) - fix Hyper-V bus registration failure caused by domain/serial number confusion (Sridhar Pitchai) - improve Hyper-V refcounting and coding style (Stephen Hemminger) - avoid potential Hyper-V hang waiting for a response that will never come (Dexuan Cui) - implement Mediatek chained IRQ handling (Honghui Zhang) - fix vendor ID & class type for Mediatek MT7622 (Honghui Zhang) - add Mobiveil PCIe host controller driver (Subrahmanya Lingappa) - add Mobiveil MSI support (Subrahmanya Lingappa) - clean up clocks, MSI, IRQ mappings in R-Car probe failure paths (Marek Vasut) - poll more frequently (5us vs 5ms) while waiting for R-Car data link active (Marek Vasut) - use generic OF parsing interface in R-Car (Vladimir Zapolskiy) - add R-Car V3H (R8A77980) "compatible" string (Sergei Shtylyov) - add R-Car gen3 PHY support (Sergei Shtylyov) - improve R-Car PHYRDY polling (Sergei Shtylyov) - clean up R-Car macros (Marek Vasut) - use runtime PM for R-Car controller clock (Dien Pham) - update arm64 defconfig for Rockchip (Shawn Lin) - refactor Rockchip code to facilitate both root port and endpoint mode (Shawn Lin) - add Rockchip endpoint mode driver (Shawn Lin) - support VMD "membar shadow" feature (Jon Derrick) - support VMD bus number offsets (Jon Derrick) - add VMD "no AER source ID" quirk for more device IDs (Jon Derrick) - remove unnecessary host controller CONFIG_PCIEPORTBUS Kconfig selections (Bjorn Helgaas) - clean up quirks.c organization and whitespace (Bjorn Helgaas) * tag 'pci-v4.18-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (144 commits) PCI/AER: Replace struct pcie_device with pci_dev PCI/AER: Remove unused parameters PCI: qcom: Include gpio/consumer.h PCI: Improve "partially hidden behind bridge" log message PCI: Improve pci_scan_bridge() and pci_scan_bridge_extend() doc PCI: Move resource distribution for single bridge outside loop PCI: Account for all bridges on bus when distributing bus numbers ACPI / hotplug / PCI: Drop unnecessary parentheses ACPI / hotplug / PCI: Mark stale PCI devices disconnected ACPI / hotplug / PCI: Don't scan bridges managed by native hotplug PCI: hotplug: Add hotplug_is_native() PCI: shpchp: Add shpchp_is_native() PCI: shpchp: Fix AMD POGO identification PCI: mobiveil: Add MSI support PCI: mobiveil: Add Mobiveil PCIe Host Bridge IP driver PCI/AER: Decode Error Source Requester ID PCI/AER: Remove aer_recover_work_func() forward declaration PCI/DPC: Use the generic pcie_do_fatal_recovery() path PCI/AER: Pass service type to pcie_do_fatal_recovery() PCI/DPC: Disable ERR_NONFATAL handling by DPC ...
2018-06-07apparmor: update git and wiki locations in AppArmor docsJordan Glover
The apparmor information in the apparmor.rst file is out of date. Update it to the correct git reference for the master apparmor tree. Update the wiki location to use apparmor.net which forwards to the current wiki location on gitlab.com. Update user space tools address to gitlab.com. Signed-off-by: Jordan Glover <Golden_Miller83@protonmail.ch> Signed-off-by: John Johansen <john.johansen@canonical.com>
2018-06-05Merge tag 'tty-4.18-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty Pull tty/serial updates from Greg KH: "Here is the big tty/serial driver update for 4.18-rc1. There's nothing major here, just lots of serial driver updates. Full details are in the shortlog, nothing anything specific to call out here. All have been in linux-next for a while with no reported issues" * tag 'tty-4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (55 commits) vt: Perform safe console erase only once serial: imx: disable UCR4_OREN on shutdown serial: imx: drop CTS/RTS handling from shutdown tty: fix typo in ASYNCB_FOURPORT comment serial: samsung: check DMA engine capabilities before using DMA mode tty: Fix data race in tty_insert_flip_string_fixed_flag tty: serial: msm_geni_serial: Fix TX infinite loop serial: 8250_dw: Fix runtime PM handling serial: 8250: omap: Fix idling of clocks for unused uarts tty: serial: drop ATH79 specific SoC symbols serial: 8250: Add missing rxtrig_bytes on Altera 16550 UART serial/aspeed-vuart: fix a couple mod_timer() calls serial: sh-sci: Use spin_{try}lock_irqsave instead of open coding version serial: 8250_of: Add IO space support tty/serial: atmel: use port->name as name in request_irq() serial: imx: dma_unmap_sg buffers on shutdown serial: imx: cleanup imx_uart_disable_dma() tty: serial: qcom_geni_serial: Add early console support tty: serial: qcom_geni_serial: Return IRQ_NONE for spurious interrupts tty: serial: qcom_geni_serial: Use iowrite32_rep to write to FIFO ...
2018-06-04Merge branch 'x86-debug-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 debug updates from Ingo Molnar: "This contains the x86 oops code printing reorganization and cleanups from Borislav Betkov, with a particular focus in enhancing opcode dumping all around" * 'x86-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/dumpstack: Explain the reasoning for the prologue and buffer size x86/dumpstack: Save first regs set for the executive summary x86/dumpstack: Add a show_ip() function x86/fault: Dump user opcode bytes on fatal faults x86/dumpstack: Add loglevel argument to show_opcodes() x86/dumpstack: Improve opcodes dumping in the code section x86/dumpstack: Carve out code-dumping into a function x86/dumpstack: Unexport oops_begin() x86/dumpstack: Remove code_bytes
2018-06-04Merge branch 'x86-boot-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 boot updates from Ingo Molnar: - Centaur CPU updates (David Wang) - AMD and other CPU topology enumeration improvements and fixes (Borislav Petkov, Thomas Gleixner, Suravee Suthikulpanit) - Continued 5-level paging work (Kirill A. Shutemov) * 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mm: Mark __pgtable_l5_enabled __initdata x86/mm: Mark p4d_offset() __always_inline x86/mm: Introduce the 'no5lvl' kernel parameter x86/mm: Stop pretending pgtable_l5_enabled is a variable x86/mm: Unify pgtable_l5_enabled usage in early boot code x86/boot/compressed/64: Fix trampoline page table address calculation x86/CPU: Move x86_cpuinfo::x86_max_cores assignment to detect_num_cpu_cores() x86/Centaur: Report correct CPU/cache topology x86/CPU: Move cpu_detect_cache_sizes() into init_intel_cacheinfo() x86/CPU: Make intel_num_cpu_cores() generic x86/CPU: Move cpu local function declarations to local header x86/CPU/AMD: Derive CPU topology from CPUID function 0xB when available x86/CPU: Modify detect_extended_topology() to return result x86/CPU/AMD: Calculate last level cache ID from number of sharing threads x86/CPU: Rename intel_cacheinfo.c to cacheinfo.c perf/events/amd/uncore: Fix amd_uncore_llc ID to use pre-defined cpu_llc_id x86/CPU/AMD: Have smp_num_siblings and cpu_llc_id always be present x86/Centaur: Initialize supported CPU features properly
2018-06-04Merge tag 'docs-4.18' of git://git.lwn.net/linuxLinus Torvalds
Pull documentation updates from Jonathan Corbet: "There's been a fair amount of work in the docs tree this time around, including: - Extensive RST conversions and organizational work in the memory-management docs thanks to Mike Rapoport. - An update of Documentation/features from Andrea Parri and a script to keep it updated. - Various LICENSES updates from Thomas, along with a script to check SPDX tags. - Work to fix dangling references to documentation files; this involved a fair number of one-liner comment changes outside of Documentation/ ... and the usual list of documentation improvements, typo fixes, etc" * tag 'docs-4.18' of git://git.lwn.net/linux: (103 commits) Documentation: document hung_task_panic kernel parameter docs/admin-guide/mm: add high level concepts overview docs/vm: move ksm and transhuge from "user" to "internals" section. docs: Use the kerneldoc comments for memalloc_no*() doc: document scope NOFS, NOIO APIs docs: update kernel versions and dates in tables docs/vm: transhuge: split userspace bits to admin-guide/mm/transhuge docs/vm: transhuge: minor updates docs/vm: transhuge: change sections order Documentation: arm: clean up Marvell Berlin family info Documentation: gpio: driver: Fix a typo and some odd grammar docs: ranoops.rst: fix location of ramoops.txt scripts/documentation-file-ref-check: rewrite it in perl with auto-fix mode docs: uio-howto.rst: use a code block to solve a warning mm, THP, doc: Add document for thp_swpout/thp_swpout_fallback w1: w1_io.c: fix a kernel-doc warning Documentation/process/posting: wrap text at 80 cols docs: admin-guide: add cgroup-v2 documentation Revert "Documentation/features/vm: Remove arch support status file for 'pte_special'" Documentation: refcount-vs-atomic: Update reference to LKMM doc. ...
2018-06-04Merge tag 'dma-mapping-4.18' of git://git.infradead.org/users/hch/dma-mappingLinus Torvalds
Pull dma-mapping updates from Christoph Hellwig: - replace the force_dma flag with a dma_configure bus method. (Nipun Gupta, although one patch is іncorrectly attributed to me due to a git rebase bug) - use GFP_DMA32 more agressively in dma-direct. (Takashi Iwai) - remove PCI_DMA_BUS_IS_PHYS and rely on the dma-mapping API to do the right thing for bounce buffering. - move dma-debug initialization to common code, and apply a few cleanups to the dma-debug code. - cleanup the Kconfig mess around swiotlb selection - swiotlb comment fixup (Yisheng Xie) - a trivial swiotlb fix. (Dan Carpenter) - support swiotlb on RISC-V. (based on a patch from Palmer Dabbelt) - add a new generic dma-noncoherent dma_map_ops implementation and use it for arc, c6x and nds32. - improve scatterlist validity checking in dma-debug. (Robin Murphy) - add a struct device quirk to limit the dma-mask to 32-bit due to bridge/system issues, and switch x86 to use it instead of a local hack for VIA bridges. - handle devices without a dma_mask more gracefully in the dma-direct code. * tag 'dma-mapping-4.18' of git://git.infradead.org/users/hch/dma-mapping: (48 commits) dma-direct: don't crash on device without dma_mask nds32: use generic dma_noncoherent_ops nds32: implement the unmap_sg DMA operation nds32: consolidate DMA cache maintainance routines x86/pci-dma: switch the VIA 32-bit DMA quirk to use the struct device flag x86/pci-dma: remove the explicit nodac and allowdac option x86/pci-dma: remove the experimental forcesac boot option Documentation/x86: remove a stray reference to pci-nommu.c core, dma-direct: add a flag 32-bit dma limits dma-mapping: remove unused gfp_t parameter to arch_dma_alloc_attrs dma-debug: check scatterlist segments c6x: use generic dma_noncoherent_ops arc: use generic dma_noncoherent_ops arc: fix arc_dma_{map,unmap}_page arc: fix arc_dma_sync_sg_for_{cpu,device} arc: simplify arc_dma_sync_single_for_{cpu,device} dma-mapping: provide a generic dma-noncoherent implementation dma-mapping: simplify Kconfig dependencies riscv: add swiotlb support riscv: only enable ZONE_DMA32 for 64-bit ...
2018-05-31arm64: Add 'ssbd' command-line optionMarc Zyngier
On a system where the firmware implements ARCH_WORKAROUND_2, it may be useful to either permanently enable or disable the workaround for cases where the user decides that they'd rather not get a trap overhead, and keep the mitigation permanently on or off instead of switching it on exception entry/exit. In any case, default to the mitigation being enabled. Reviewed-by: Julien Grall <julien.grall@arm.com> Reviewed-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-05-29Documentation: document hung_task_panic kernel parameterOmar Sandoval
This parameter has been around since commit e162b39a368f ("softlockup: decouple hung tasks check from softlockup detection") in 2009 but was never documented. Signed-off-by: Omar Sandoval <osandov@fb.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-05-29docs/admin-guide/mm: add high level concepts overviewMike Rapoport
The are terms that seem obvious to the mm developers, but may be somewhat obscure for, say, less involved readers. The concepts overview can be seen as an "extended glossary" that introduces such terms to the readers of the kernel documentation. Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-05-28x86/pci-dma: remove the experimental forcesac boot optionChristoph Hellwig
Limiting the dma mask to avoid PCI (pre-PCIe) DAC cycles while paying the huge overhead of an IOMMU is rather pointless, and this seriously gets in the way of dma mapping work. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
2018-05-21Merge branch 'speck-v20' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Merge speculative store buffer bypass fixes from Thomas Gleixner: - rework of the SPEC_CTRL MSR management to accomodate the new fancy SSBD (Speculative Store Bypass Disable) bit handling. - the CPU bug and sysfs infrastructure for the exciting new Speculative Store Bypass 'feature'. - support for disabling SSB via LS_CFG MSR on AMD CPUs including Hyperthread synchronization on ZEN. - PRCTL support for dynamic runtime control of SSB - SECCOMP integration to automatically disable SSB for sandboxed processes with a filter flag for opt-out. - KVM integration to allow guests fiddling with SSBD including the new software MSR VIRT_SPEC_CTRL to handle the LS_CFG based oddities on AMD. - BPF protection against SSB .. this is just the core and x86 side, other architecture support will come separately. * 'speck-v20' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (49 commits) bpf: Prevent memory disambiguation attack x86/bugs: Rename SSBD_NO to SSB_NO KVM: SVM: Implement VIRT_SPEC_CTRL support for SSBD x86/speculation, KVM: Implement support for VIRT_SPEC_CTRL/LS_CFG x86/bugs: Rework spec_ctrl base and mask logic x86/bugs: Remove x86_spec_ctrl_set() x86/bugs: Expose x86_spec_ctrl_base directly x86/bugs: Unify x86_spec_ctrl_{set_guest,restore_host} x86/speculation: Rework speculative_store_bypass_update() x86/speculation: Add virtualized speculative store bypass disable support x86/bugs, KVM: Extend speculation control for VIRT_SPEC_CTRL x86/speculation: Handle HT correctly on AMD x86/cpufeatures: Add FEATURE_ZEN x86/cpufeatures: Disentangle SSBD enumeration x86/cpufeatures: Disentangle MSR_SPEC_CTRL enumeration from IBRS x86/speculation: Use synthetic bits for IBRS/IBPB/STIBP KVM: SVM: Move spec control call after restore of GS x86/cpu: Make alternative_msr_write work for 32-bit code x86/bugs: Fix the parameters alignment and missing void x86/bugs: Make cpu_show_common() static ...