user/sven/linux.git/drivers/base, branch v5.0.12

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

2019-04-27T07:37:45Z

commit 37803841c92d7b327147e0b1be3436423189e1cf upstream. 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 Signed-off-by: Greg Kroah-Hartman

PM / Domains: Avoid a potential deadlock

2019-04-20T07:16:57Z

[ Upstream commit 2071ac985d37efe496782c34318dbead93beb02f ] 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 Signed-off-by: Sasha Levin

PM / wakeup: Rework wakeup source timer cancellation

2019-03-23T19:11:36Z

commit 1fad17fb1bbcd73159c2b992668a6957ecc5af8a upstream. 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 Signed-off-by: Greg Kroah-Hartman

driver core: Postpone DMA tear-down until after devres release

2019-03-10T06:08:58Z

commit 376991db4b6464e906d699ef07681e2ffa8ab08c upstream. When unbinding the (IOMMU-enabled) R-Car SATA device on Salvator-XS (R-Car H3 ES2.0), in preparation of rebinding against vfio-platform for device pass-through for virtualization: echo ee300000.sata > /sys/bus/platform/drivers/sata_rcar/unbind the kernel crashes with: Unable to handle kernel paging request at virtual address ffffffbf029ffffc Mem abort info: ESR = 0x96000006 Exception class = DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 Data abort info: ISV = 0, ISS = 0x00000006 CM = 0, WnR = 0 swapper pgtable: 4k pages, 39-bit VAs, pgdp = 000000007e8c586c [ffffffbf029ffffc] pgd=000000073bfc6003, pud=000000073bfc6003, pmd=0000000000000000 Internal error: Oops: 96000006 [#1] SMP Modules linked in: CPU: 0 PID: 1098 Comm: bash Not tainted 5.0.0-rc5-salvator-x-00452-g37596f884f4318ef #287 Hardware name: Renesas Salvator-X 2nd version board based on r8a7795 ES2.0+ (DT) pstate: 60400005 (nZCv daif +PAN -UAO) pc : __free_pages+0x8/0x58 lr : __dma_direct_free_pages+0x50/0x5c sp : ffffff801268baa0 x29: ffffff801268baa0 x28: 0000000000000000 x27: ffffffc6f9c60bf0 x26: ffffffc6f9c60bf0 x25: ffffffc6f9c60810 x24: 0000000000000000 x23: 00000000fffff000 x22: ffffff8012145000 x21: 0000000000000800 x20: ffffffbf029fffc8 x19: 0000000000000000 x18: ffffffc6f86c42c8 x17: 0000000000000000 x16: 0000000000000070 x15: 0000000000000003 x14: 0000000000000000 x13: ffffff801103d7f8 x12: 0000000000000028 x11: ffffff8011117604 x10: 0000000000009ad8 x9 : ffffff80110126d0 x8 : ffffffc6f7563000 x7 : 6b6b6b6b6b6b6b6b x6 : 0000000000000018 x5 : ffffff8011cf3cc8 x4 : 0000000000004000 x3 : 0000000000080000 x2 : 0000000000000001 x1 : 0000000000000000 x0 : ffffffbf029fffc8 Process bash (pid: 1098, stack limit = 0x00000000c38e3e32) Call trace: __free_pages+0x8/0x58 __dma_direct_free_pages+0x50/0x5c arch_dma_free+0x1c/0x98 dma_direct_free+0x14/0x24 dma_free_attrs+0x9c/0xdc dmam_release+0x18/0x20 release_nodes+0x25c/0x28c devres_release_all+0x48/0x4c device_release_driver_internal+0x184/0x1f0 device_release_driver+0x14/0x1c unbind_store+0x70/0xb8 drv_attr_store+0x24/0x34 sysfs_kf_write+0x4c/0x64 kernfs_fop_write+0x154/0x1c4 __vfs_write+0x34/0x164 vfs_write+0xb4/0x16c ksys_write+0x5c/0xbc __arm64_sys_write+0x14/0x1c el0_svc_common+0x98/0x114 el0_svc_handler+0x1c/0x24 el0_svc+0x8/0xc Code: d51b4234 17fffffa a9bf7bfd 910003fd (b9403404) ---[ end trace 8c564cdd3a1a840f ]--- While I've bisected this to commit e8e683ae9a736407 ("iommu/of: Fix probe-deferral"), and reverting that commit on post-v5.0-rc4 kernels does fix the problem, this turned out to be a red herring. On arm64, arch_teardown_dma_ops() resets dev->dma_ops to NULL. Hence if a driver has used a managed DMA allocation API, the allocated DMA memory will be freed using the direct DMA ops, while it may have been allocated using a custom DMA ops (iommu_dma_ops in this case). Fix this by reversing the order of the calls to devres_release_all() and arch_teardown_dma_ops(). Signed-off-by: Geert Uytterhoeven Acked-by: Christoph Hellwig Reviewed-by: Rafael J. Wysocki Cc: stable Reviewed-by: Robin Murphy Signed-off-by: Greg Kroah-Hartman

PM-runtime: Fix deadlock when canceling hrtimer

2019-02-21T09:29:00Z

When rpm_resume() desactivates the autosuspend timer, it should only try to cancel hrtimer but not wait for the handler to finish, because both rpm_resume() and pm_suspend_timer_fn() take the power.lock. A deadlock is possible as follows: CPU0 CPU1 rpm_resume() spin_lock_irqsave pm_suspend_timer_fn() spin_lock_irqsave pm_runtime_deactivate_timer() hrtimer_cancel() It is sufficient to call hrtimer_try_to_cancel() from pm_runtime_deactivate_timer(), because dev->power.timer_expires reset to 0 by it, so use that function instead of hrtimer_cancel(). Fixes: 8234f6734c5d ("PM-runtime: Switch autosuspend over to using hrtimers") Reported-by: Sunzhaosheng Sun(Zhaosheng) Signed-off-by: Vincent Guittot [ rjw: Changelog ] Signed-off-by: Rafael J. Wysocki

Merge tag 'driver-core-5.0-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

2019-02-08T18:53:44Z

Pull driver core fixes from Greg KH: "Here are some driver core fixes for 5.0-rc6. Well, not so much "driver core" as "debugfs". There's a lot of outstanding debugfs cleanup patches coming in through different subsystem trees, and in that process the debugfs core was found that it really should return errors when something bad happens, to prevent random files from showing up in the root of debugfs afterward. So debugfs was fixed up to handle this properly, and then two fixes for the relay and blk-mq code was needed as it was making invalid assumptions about debugfs return values. There's also a cacheinfo fix in here that resolves a tiny issue. All of these have been in linux-next for over a week with no reported problems" * tag 'driver-core-5.0-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: blk-mq: protect debugfs_create_files() from failures relay: check return of create_buf_file() properly debugfs: debugfs_lookup() should return NULL if not found debugfs: return error values, not NULL debugfs: fix debugfs_rename parameter checking cacheinfo: Keep the old value if of_property_read_u32 fails

PM-runtime: Fix deadlock with ktime_get()

2019-01-30T21:49:06Z

A deadlock has been seen when swicthing clocksources which use PM-runtime. The call path is: change_clocksource ... write_seqcount_begin ... timekeeping_update ... sh_cmt_clocksource_enable ... rpm_resume pm_runtime_mark_last_busy ktime_get do read_seqcount_begin while read_seqcount_retry .... write_seqcount_end Although we should be safe because we haven't yet changed the clocksource at that time, we can't do that because of seqcount protection. Use ktime_get_mono_fast_ns() instead which is lock safe for such cases. With ktime_get_mono_fast_ns, the timestamp is not guaranteed to be monotonic across an update and as a result can goes backward. According to update_fast_timekeeper() description: "In the worst case, this can result is a slightly wrong timestamp (a few nanoseconds)". For PM-runtime autosuspend, this means only that the suspend decision may be slightly suboptimal. Fixes: 8234f6734c5d ("PM-runtime: Switch autosuspend over to using hrtimers") Reported-by: Biju Das Signed-off-by: Vincent Guittot Reviewed-by: Ulf Hansson Signed-off-by: Rafael J. Wysocki

cacheinfo: Keep the old value if of_property_read_u32 fails

2019-01-22T12:50:31Z

Commit 448a5a552f336bd7b847b1951 ("drivers: base: cacheinfo: use OF property_read_u32 instead of get_property,read_number") makes cache size and number_of_sets be 0 if DT doesn't provide there values. I think this is unreasonable so make them keep the old values, which is the same as old kernels. Fixes: 448a5a552f33 ("drivers: base: cacheinfo: use OF property_read_u32 instead of get_property,read_number") Cc: stable@vger.kernel.org Signed-off-by: Huacai Chen Reviewed-by: Sudeep Holla Signed-off-by: Greg Kroah-Hartman

Merge tag 'regmap-fix-v5.0-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap

2019-01-18T19:17:19Z

Pull regmap fixes from Mark Brown: "The cleanups for the way we handle type information introduced during the merge window revealed that we'd been abusing the irq APIs for a long time, causing breakage for systems. This has a couple of minimal fixes for that which restore the previous behaviour for the time being, we'll fix it properly for v5.1 but that'd be a bit much to do as a bug fix" * tag 'regmap-fix-v5.0-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap: regmap-irq: do not write mask register if mask_base is zero regmap: regmap-irq: silently ignore unsupported type settings

regmap-irq: do not write mask register if mask_base is zero

2019-01-14T22:11:22Z

If client have not provided the mask base register then do not write into the mask register. Signed-off-by: Laxman Dewangan Signed-off-by: Jinyoung Park Signed-off-by: Venkat Reddy Talla Signed-off-by: Mark Zhang Signed-off-by: Mark Brown