linux/drivers/base, branch v5.1

mm/memory_hotplug: do not unlock after failing to take the device_hotplug_lock

2019-04-19T16:46:04Z

When adding memory by probing a memory block in the sysfs interface, there is an obvious issue where we will unlock the device_hotplug_lock when we failed to takes it. That issue was introduced in 8df1d0e4a265 ("mm/memory_hotplug: make add_memory() take the device_hotplug_lock"). We should drop out in time when failing to take the device_hotplug_lock. Link: http://lkml.kernel.org/r/1554696437-9593-1-git-send-email-zhongjiang@huawei.com Fixes: 8df1d0e4a265 ("mm/memory_hotplug: make add_memory() take the device_hotplug_lock") Signed-off-by: zhong jiang Reported-by: Yang yingliang Acked-by: Michal Hocko Reviewed-by: David Hildenbrand Reviewed-by: Oscar Salvador Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Merge tag 'devprop-5.1-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

2019-03-22T19:08:52Z

Pull device properties framework fix from Rafael Wysocki: "Add missing 'static' in two places (YueHaibing)" * tag 'devprop-5.1-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: drivers: base: swnode: Make two functions static

PM / Domains: Avoid a potential deadlock

2019-03-19T21:58:04Z

Lockdep warns that prepare_lock and genpd->mlock can cause a deadlock the deadlock scenario is like following: First thread is probing cs2000 cs2000_probe() clk_register() __clk_core_init() clk_prepare_lock() ----> acquires prepare_lock cs2000_recalc_rate() i2c_smbus_read_byte_data() rcar_i2c_master_xfer() dma_request_chan() rcar_dmac_of_xlate() rcar_dmac_alloc_chan_resources() pm_runtime_get_sync() __pm_runtime_resume() rpm_resume() rpm_callback() genpd_runtime_resume() ----> acquires genpd->mlock Second thread is attaching any device to the same PM domain genpd_add_device() genpd_lock() ----> acquires genpd->mlock cpg_mssr_attach_dev() of_clk_get_from_provider() __of_clk_get_from_provider() __clk_create_clk() clk_prepare_lock() ----> acquires prepare_lock Since currently no PM provider access genpd's critical section in .attach_dev, and .detach_dev callbacks, so there is no need to protect these two callbacks with genpd->mlock. This patch avoids a potential deadlock by moving out .attach_dev and .detach_dev from genpd->mlock, so that genpd->mlock won't be held when prepare_lock is acquired in .attach_dev and .detach_dev Signed-off-by: Jiada Wang Reviewed-by: Ulf Hansson Tested-by: Geert Uytterhoeven Reviewed-by: Geert Uytterhoeven Signed-off-by: Rafael J. Wysocki

drivers: base: swnode: Make two functions static

2019-03-19T15:37:56Z

Fix sparse warning: drivers/base/swnode.c:475:22: warning: symbol 'software_node_get_parent' was not declared. Should it be static? drivers/base/swnode.c:484:22: warning: symbol 'software_node_get_next_child' was not declared. Should it be static? Signed-off-by: YueHaibing Signed-off-by: Rafael J. Wysocki

Merge tag 'devdax-for-5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

2019-03-16T20:05:32Z

Pull device-dax updates from Dan Williams: "New device-dax infrastructure to allow persistent memory and other "reserved" / performance differentiated memories, to be assigned to the core-mm as "System RAM". Some users want to use persistent memory as additional volatile memory. They are willing to cope with potential performance differences, for example between DRAM and 3D Xpoint, and want to use typical Linux memory management apis rather than a userspace memory allocator layered over an mmap() of a dax file. The administration model is to decide how much Persistent Memory (pmem) to use as System RAM, create a device-dax-mode namespace of that size, and then assign it to the core-mm. The rationale for device-dax is that it is a generic memory-mapping driver that can be layered over any "special purpose" memory, not just pmem. On subsequent boots udev rules can be used to restore the memory assignment. One implication of using pmem as RAM is that mlock() no longer keeps data off persistent media. For this reason it is recommended to enable NVDIMM Security (previously merged for 5.0) to encrypt pmem contents at rest. We considered making this recommendation an actively enforced requirement, but in the end decided to leave it as a distribution / administrator policy to allow for emulation and test environments that lack security capable NVDIMMs. Summary: - Replace the /sys/class/dax device model with /sys/bus/dax, and include a compat driver so distributions can opt-in to the new ABI. - Allow for an alternative driver for the device-dax address-range - Introduce the 'kmem' driver to hotplug / assign a device-dax address-range to the core-mm. - Arrange for the device-dax target-node to be onlined so that the newly added memory range can be uniquely referenced by numa apis" NOTE! I'm not entirely happy with the whole "PMEM as RAM" model because we currently have special - and very annoying rules in the kernel about accessing PMEM only with the "MC safe" accessors, because machine checks inside the regular repeat string copy functions can be fatal in some (not described) circumstances. And apparently the PMEM modules can cause that a lot more than regular RAM. The argument is that this happens because PMEM doesn't necessarily get scrubbed at boot like RAM does, but that is planned to be added for the user space tooling. Quoting Dan from another email: "The exposure can be reduced in the volatile-RAM case by scanning for and clearing errors before it is onlined as RAM. The userspace tooling for that can be in place before v5.1-final. There's also runtime notifications of errors via acpi_nfit_uc_error_notify() from background scrubbers on the DIMM devices. With that mechanism the kernel could proactively clear newly discovered poison in the volatile case, but that would be additional development more suitable for v5.2. I understand the concern, and the need to highlight this issue by tapping the brakes on feature development, but I don't see PMEM as RAM making the situation worse when the exposure is also there via DAX in the PMEM case. Volatile-RAM is arguably a safer use case since it's possible to repair pages where the persistent case needs active application coordination" * tag 'devdax-for-5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: device-dax: "Hotplug" persistent memory for use like normal RAM mm/resource: Let walk_system_ram_range() search child resources mm/memory-hotplug: Allow memory resources to be children mm/resource: Move HMM pr_debug() deeper into resource code mm/resource: Return real error codes from walk failures device-dax: Add a 'modalias' attribute to DAX 'bus' devices device-dax: Add a 'target_node' attribute device-dax: Auto-bind device after successful new_id acpi/nfit, device-dax: Identify differentiated memory with a unique numa-node device-dax: Add /sys/class/dax backwards compatibility device-dax: Add support for a dax override driver device-dax: Move resource pinning+mapping into the common driver device-dax: Introduce bus + driver model device-dax: Start defining a dax bus model device-dax: Remove multi-resource infrastructure device-dax: Kill dax_region base device-dax: Kill dax_region ida

Merge tag 'pm-5.1-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

2019-03-14T17:30:06Z

Pull more power management updates from Rafael Wysocki: "These are mostly fixes and cleanups on top of the previously merged power management material for 5.1-rc1 with one cpupower utility update that wasn't pushed earlier due to unfortunate timing. Specifics: - Fix registration of new cpuidle governors partially broken during the 5.0 development cycle by mistake (Rafael Wysocki). - Avoid integer overflows in the menu cpuidle governor by making it discard the overflowing data points upfront (Rafael Wysocki). - Fix minor mistake in the recent update of the iowait boost computation in the intel_pstate driver (Rafael Wysocki). - Drop incorrect __init annotation from one function in the pxa2xx cpufreq driver (Arnd Bergmann). - Fix the operating performance points (OPP) framework initialization for devices in multiple power domains if only one of them is scalable (Rajendra Nayak). - Fix mistake in dev_pm_opp_set_rate() which causes it to skip updating the performance state if the new frequency is the same as the old one (Viresh Kumar). - Rework the cancellation of wakeup source timers to avoid potential issues with it and do some cleanups unlocked by that change (Viresh Kumar, Rafael Wysocki). - Clean up the code computing the active/suspended time of devices in the PM-runtime framework after recent changes (Ulf Hansson). - Make the power management infrastructure code use pr_fmt() consistently (Joe Perches). - Clean up the generic power domains (genpd) framework somewhat (Aisheng Dong). - Improve kerneldoc comments for two functions in the cpufreq core (Rafael Wysocki). - Fix typo in a PM QoS file description comment (Aisheng Dong). - Update the handling of CPU boost frequencies in the cpupower utility (Abhishek Goel)" * tag 'pm-5.1-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: cpuidle: governor: Add new governors to cpuidle_governors again cpufreq: intel_pstate: Fix up iowait_boost computation PM / OPP: Update performance state when freq == old_freq PM / wakeup: Drop wakeup_source_drop() PM / wakeup: Rework wakeup source timer cancellation PM / domains: Remove one unnecessary blank line PM / Domains: Return early for all errors in _genpd_power_off() PM / Domains: Improve warn for multiple states but no governor OPP: Fix handling of multiple power domains PM / QoS: Fix typo in file description cpufreq: pxa2xx: remove incorrect __init annotation PM-runtime: Call pm_runtime_active|suspended_time() from sysfs PM-runtime: Consolidate code to get active/suspended time PM: Add and use pr_fmt() cpufreq: Improve kerneldoc comments for cpufreq_cpu_get/put() cpuidle: menu: Avoid overflows when computing variance tools/power/cpupower: Display boost frequency separately

Merge branch 'pm-domains'

2019-03-14T09:53:08Z

* pm-domains: PM / domains: Remove one unnecessary blank line PM / Domains: Return early for all errors in _genpd_power_off() PM / Domains: Improve warn for multiple states but no governor

Merge branches 'pm-core', 'pm-sleep' and 'pm-qos'

2019-03-14T09:51:38Z

* pm-core: PM-runtime: Call pm_runtime_active|suspended_time() from sysfs PM-runtime: Consolidate code to get active/suspended time * pm-sleep: PM / wakeup: Drop wakeup_source_drop() PM / wakeup: Rework wakeup source timer cancellation * pm-qos: PM / QoS: Fix typo in file description

PM / wakeup: Drop wakeup_source_drop()

2019-03-12T08:43:00Z

After commit d856f39ac1cc ("PM / wakeup: Rework wakeup source timer cancellation") wakeup_source_drop() is a trivial wrapper around __pm_relax() and it has no users except for wakeup_source_destroy() and wakeup_source_trash() which also has no users, so drop it along with the latter and make wakeup_source_destroy() call __pm_relax() directly. Signed-off-by: Rafael J. Wysocki Acked-by: Viresh Kumar

PM / wakeup: Rework wakeup source timer cancellation

2019-03-12T08:40:48Z

If wakeup_source_add() is called right after wakeup_source_remove() for the same wakeup source, timer_setup() may be called for a potentially scheduled timer which is incorrect. To avoid that, move the wakeup source timer cancellation from wakeup_source_drop() to wakeup_source_remove(). Moreover, make wakeup_source_remove() clear the timer function after canceling the timer to let wakeup_source_not_registered() treat unregistered wakeup sources in the same way as the ones that have never been registered. Signed-off-by: Viresh Kumar Cc: 4.4+ # 4.4+ [ rjw: Subject, changelog, merged two patches together ] Signed-off-by: Rafael J. Wysocki