linux/drivers/base, branch v3.12.24

drivercore: deferral race condition fix

2014-06-06T09:40:24Z

commit 58b116bce13612e5aa6fcd49ecbd4cf8bb59e835 upstream. When the kernel is built with CONFIG_PREEMPT it is possible to reach a state when all modules loaded but some driver still stuck in the deferred list and there is a need for external event to kick the deferred queue to probe these drivers. The issue has been observed on embedded systems with CONFIG_PREEMPT enabled, audio support built as modules and using nfsroot for root filesystem. The following log fragment shows such sequence when all audio modules were loaded but the sound card is not present since the machine driver has failed to probe due to missing dependency during it's probe. The board is am335x-evmsk (McASP<->tlv320aic3106 codec) with davinci-evm machine driver: ... [ 12.615118] davinci-mcasp 4803c000.mcasp: davinci_mcasp_probe: ENTER [ 12.719969] davinci_evm sound.3: davinci_evm_probe: ENTER [ 12.725753] davinci_evm sound.3: davinci_evm_probe: snd_soc_register_card [ 12.753846] davinci-mcasp 4803c000.mcasp: davinci_mcasp_probe: snd_soc_register_component [ 12.922051] davinci-mcasp 4803c000.mcasp: davinci_mcasp_probe: snd_soc_register_component DONE [ 12.950839] davinci_evm sound.3: ASoC: platform (null) not registered [ 12.957898] davinci_evm sound.3: davinci_evm_probe: snd_soc_register_card DONE (-517) [ 13.099026] davinci-mcasp 4803c000.mcasp: Kicking the deferred list [ 13.177838] davinci-mcasp 4803c000.mcasp: really_probe: probe_count = 2 [ 13.194130] davinci_evm sound.3: snd_soc_register_card failed (-517) [ 13.346755] davinci_mcasp_driver_init: LEAVE [ 13.377446] platform sound.3: Driver davinci_evm requests probe deferral [ 13.592527] platform sound.3: really_probe: probe_count = 0 In the log the machine driver enters it's probe at 12.719969 (this point it has been removed from the deferred lists). McASP driver already executing it's probing (since 12.615118). The machine driver tries to construct the sound card (12.950839) but did not found one of the components so it fails. After this McASP driver registers all the ASoC components (the machine driver still in it's probe function after it failed to construct the card) and the deferred work is prepared at 13.099026 (note that this time the machine driver is not in the lists so it is not going to be handled when the work is executing). Lastly the machine driver exit from it's probe and the core places it to the deferred list but there will be no other driver going to load and the deferred queue is not going to be kicked again - till we have external event like connecting USB stick, etc. The proposed solution is to try the deferred queue once more when the last driver is asking for deferring and we had drivers loaded while this last driver was probing. This way we can avoid drivers stuck in the deferred queue. Signed-off-by: Grant Likely Reviewed-by: Peter Ujfalusi Tested-by: Peter Ujfalusi Acked-by: Greg Kroah-Hartman Cc: Mark Brown Signed-off-by: Jiri Slaby

PM / hibernate: Fix restore hang in freeze_processes()

2014-03-05T16:13:55Z

commit f8d5b9e9e5372f0deb7bc1ab1088a9b60b0a793d upstream. During restore, pm_notifier chain are called with PM_RESTORE_PREPARE. The firmware_class driver handler fw_pm_notify does not have a handler for this. As a result, it keeps a reader on the kmod.c umhelper_sem. During freeze_processes, the call to __usermodehelper_disable tries to take a write lock on this semaphore and hangs waiting. Signed-off-by: Sebastian Capella Acked-by: Ming Lei Signed-off-by: Rafael J. Wysocki Signed-off-by: Jiri Slaby

PM / runtime: Use pm_runtime_put_sync() in __device_release_driver()

2013-12-04T19:05:37Z

commit baab52ded242c35a2290e1fa82e0cc147d0d8c1a upstream. Commit fa180eb448fa (PM / Runtime: Idle devices asynchronously after probe|release) modified __device_release_driver() to call pm_runtime_put(dev) instead of pm_runtime_put_sync(dev) before detaching the driver from the device. However, that was a mistake, because pm_runtime_put(dev) causes rpm_idle() to be queued up and the driver may be gone already when that function is executed. That breaks the assumptions the drivers have the right to make about the core's behavior on the basis of the existing documentation and actually causes problems to happen, so revert that part of commit fa180eb448fa and restore the previous behavior of __device_release_driver(). Reported-by: Tomi Valkeinen Fixes: fa180eb448fa (PM / Runtime: Idle devices asynchronously after probe|release) Signed-off-by: Rafael J. Wysocki Acked-by: Kevin Hilman Acked-by: Ulf Hansson Signed-off-by: Greg Kroah-Hartman

driver core: Release device_hotplug_lock when store_mem_state returns EINVAL

2013-10-17T01:42:41Z

When inserting a wrong value to /sys/devices/system/memory/memoryX/state file, following messages are shown. And device_hotplug_lock is never released. ================================================ [ BUG: lock held when returning to user space! ] 3.12.0-rc4-debug+ #3 Tainted: G W ------------------------------------------------ bash/6442 is leaving the kernel with locks still held! 1 lock held by bash/6442: #0: (device_hotplug_lock){+.+.+.}, at: [] lock_device_hotplug_sysfs+0x15/0x50 This issue was introdued by commit fa2be40 (drivers: base: use standard device online/offline for state change). This patch releases device_hotplug_lcok when store_mem_state returns EINVAL. Signed-off-by: Yasuaki Ishimatsu Reviewed-by: Toshi Kani CC: Seth Jennings Signed-off-by: Greg Kroah-Hartman

driver core : Fix use after free of dev->parent in device_shutdown

2013-09-26T21:46:11Z

The put_device(dev) at the bottom of the loop of device_shutdown may result in the dev being cleaned up. In device_create_release, the dev is kfreed. However, device_shutdown attempts to use the dev pointer again after put_device by referring to dev->parent. Copy the parent pointer instead to avoid this condition. This bug was found on Chromium OS's chromeos-3.8, which is based on v3.8.11. See bug report : https://code.google.com/p/chromium/issues/detail?id=297842 This can easily be reproduced when shutting down with hidraw devices that report battery condition. Two examples are the HP Bluetooth Mouse X4000b and the Apple Magic Mouse. For example, with the magic mouse : The dev in question is "hidraw0" dev->parent is "magicmouse" In the course of the shutdown for this device, the input event cleanup calls a put on hidraw0, decrementing its reference count. When we finally get to put_device(dev) in device_shutdown, kobject_cleanup is called and device_create_release does kfree(dev). dev->parent is no longer valid, and we may crash in put_device(dev->parent). This change should be applied on any kernel with this change : d1c6c030fcec6f860d9bb6c632a3ebe62e28440b Cc: stable@vger.kernel.org Signed-off-by: Benson Leung Reviewed-by: Ming Lei Signed-off-by: Greg Kroah-Hartman

thp: account anon transparent huge pages into NR_ANON_PAGES

2013-09-12T22:38:03Z

We use NR_ANON_PAGES as base for reporting AnonPages to user. There's not much sense in not accounting transparent huge pages there, but add them on printing to user. Let's account transparent huge pages in NR_ANON_PAGES in the first place. Signed-off-by: Kirill A. Shutemov Acked-by: Dave Hansen Cc: Andrea Arcangeli Cc: Al Viro Cc: Hugh Dickins Cc: Wu Fengguang Cc: Jan Kara Cc: Mel Gorman Cc: Andi Kleen Cc: Matthew Wilcox Cc: Hillf Danton Cc: Ning Qu Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

dma-buf: Expose buffer size to userspace (v2)

2013-09-10T06:06:45Z

Each dma-buf has an associated size and it's reasonable for userspace to want to know what it is. Since userspace already has an fd, expose the size using the size = lseek(fd, SEEK_END, 0); lseek(fd, SEEK_CUR, 0); idiom. v2: Added Daniel's sugeested documentation, with minor fixups Signed-off-by: Christopher James Halse Rogers Reviewed-by: Daniel Vetter Tested-by: Daniel Vetter Signed-off-by: Sumit Semwal

dma-buf: Check return value of anon_inode_getfile

2013-09-10T05:59:21Z

anon_inode_getfile might fail, so check its return value. Signed-off-by: Tuomas Tynkkynen Signed-off-by: Sumit Semwal

Merge branch 'for-v3.12' of git://git.linaro.org/people/mszyprowski/linux-dma-mapping

2013-09-09T17:26:33Z

Pull DMA mapping update from Marek Szyprowski: "This contains an addition of Device Tree support for reserved memory regions (Contiguous Memory Allocator is one of the drivers for it) and changes required by the KVM extensions for PowerPC architectue" * 'for-v3.12' of git://git.linaro.org/people/mszyprowski/linux-dma-mapping: ARM: init: add support for reserved memory defined by device tree drivers: of: add initialization code for dma reserved memory drivers: of: add function to scan fdt nodes given by path drivers: dma-contiguous: clean source code and prepare for device tree

Merge branch 'next' of git://git.kernel.org/pub/scm/virt/kvm/kvm

2013-09-05T01:15:06Z

Pull KVM updates from Gleb Natapov: "The highlights of the release are nested EPT and pv-ticketlocks support (hypervisor part, guest part, which is most of the code, goes through tip tree). Apart of that there are many fixes for all arches" Fix up semantic conflicts as discussed in the pull request thread.. * 'next' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (88 commits) ARM: KVM: Add newlines to panic strings ARM: KVM: Work around older compiler bug ARM: KVM: Simplify tracepoint text ARM: KVM: Fix kvm_set_pte assignment ARM: KVM: vgic: Bump VGIC_NR_IRQS to 256 ARM: KVM: Bugfix: vgic_bytemap_get_reg per cpu regs ARM: KVM: vgic: fix GICD_ICFGRn access ARM: KVM: vgic: simplify vgic_get_target_reg KVM: MMU: remove unused parameter KVM: PPC: Book3S PR: Rework kvmppc_mmu_book3s_64_xlate() KVM: PPC: Book3S PR: Make instruction fetch fallback work for system calls KVM: PPC: Book3S PR: Don't corrupt guest state when kernel uses VMX KVM: x86: update masterclock when kvmclock_offset is calculated (v2) KVM: PPC: Book3S: Fix compile error in XICS emulation KVM: PPC: Book3S PR: return appropriate error when allocation fails arch: powerpc: kvm: add signed type cast for comparation KVM: x86: add comments where MMIO does not return to the emulator KVM: vmx: count exits to userspace during invalid guest emulation KVM: rename __kvm_io_bus_sort_cmp to kvm_io_bus_cmp kvm: optimize away THP checks in kvm_is_mmio_pfn() ...