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2018-05-27PM / suspend: Prevent might sleep splatsThomas Gleixner
timekeeping suspend/resume calls read_persistent_clock() which takes rtc_lock. That results in might sleep warnings because at that point we run with interrupts disabled. We cannot convert rtc_lock to a raw spinlock as that would trigger other might sleep warnings. As a workaround we disable the might sleep warnings by setting system_state to SYSTEM_SUSPEND before calling sysdev_suspend() and restoring it to SYSTEM_RUNNING afer sysdev_resume(). There is no lock contention because hibernate / suspend to RAM is single-CPU at this point. In s2idle's case the system_state is set to SYSTEM_SUSPEND before timekeeping_suspend() which is invoked by the last CPU. In the resume case it set back to SYSTEM_RUNNING after timekeeping_resume() which is invoked by the first CPU in the resume case. The other CPUs will block on tick_freeze_lock. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> [bigeasy: cover s2idle in tick_freeze() / tick_unfreeze()] Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-05-26Merge tag 'armsoc-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc Pull ARM SoC fixes from Olof Johansson: "A few more fixes for v4.17: - a fix for a crash in scm_call_atomic on qcom platforms - display fix for Allwinner A10 - a fix that re-enables ethernet on Allwinner H3 (C.H.I.P et al) - a fix for eMMC corruption on hikey - i2c-gpio descriptor tables for ixp4xx ... plus a small typo fix" * tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: ARM: Fix i2c-gpio GPIO descriptor tables arm64: dts: hikey: Fix eMMC corruption regression firmware: qcom: scm: Fix crash in qcom_scm_call_atomic1() ARM: sun8i: v3s: fix spelling mistake: "disbaled" -> "disabled" ARM: dts: sun4i: Fix incorrect clocks for displays ARM: dts: sun8i: h3: Re-enable EMAC on Orange Pi One
2018-05-26Merge branch 'x86-pti-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 store buffer fixes from Thomas Gleixner: "Two fixes for the SSBD mitigation code: - expose SSBD properly to guests. This got broken when the CPU feature flags got reshuffled. - simplify the CPU detection logic to avoid duplicate entries in the tables" * 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/speculation: Simplify the CPU bug detection logic KVM/VMX: Expose SSBD properly to guests
2018-05-26Merge branch 'sched-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler fixes from Thomas Gleixner: "Three fixes for scheduler and kthread code: - allow calling kthread_park() on an already parked thread - restore the sched_pi_setprio() tracepoint behaviour - clarify the unclear string for the scheduling domain debug output" * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched, tracing: Fix trace_sched_pi_setprio() for deboosting kthread: Allow kthread_park() on a parked kthread sched/topology: Clarify root domain(s) debug string
2018-05-26Merge tag 'hisi-fixes-for-4.17v2' of git://github.com/hisilicon/linux-hisi ↵Olof Johansson
into fixes ARM64: hisi fixes for 4.17 - Remove eMMC max-frequency property to fix eMMC corruption on hikey board * tag 'hisi-fixes-for-4.17v2' of git://github.com/hisilicon/linux-hisi: arm64: dts: hikey: Fix eMMC corruption regression Signed-off-by: Olof Johansson <olof@lixom.net>
2018-05-26ARM: Fix i2c-gpio GPIO descriptor tablesLinus Walleij
I used bad names in my clumsiness when rewriting many board files to use GPIO descriptors instead of platform data. A few had the platform_device ID set to -1 which would indeed give the device name "i2c-gpio". But several had it set to >=0 which gives the names "i2c-gpio.0", "i2c-gpio.1" ... Fix the offending instances in the ARM tree. Sorry for the mess. Fixes: b2e63555592f ("i2c: gpio: Convert to use descriptors") Cc: Wolfram Sang <wsa@the-dreams.de> Cc: Simon Guinot <simon.guinot@sequanux.org> Reported-by: Simon Guinot <simon.guinot@sequanux.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Olof Johansson <olof@lixom.net>
2018-05-26switch the rest of procfs lookups to d_splice_alias()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-05-26procfs: switch instantiate_t to d_splice_alias()Al Viro
... and get rid of pointless struct inode *dir argument of those, while we are at it. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-05-26don't bother with tid_fd_revalidate() in lookupsAl Viro
what we want it for is actually updating inode metadata; take _that_ into a separate helper and use it. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-05-26Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull KVM fixes from Radim Krčmář: "PPC: - Close a hole which could possibly lead to the host timebase getting out of sync. - Three fixes relating to PTEs and TLB entries for radix guests. - Fix a bug which could lead to an interrupt never getting delivered to the guest, if it is pending for a guest vCPU when the vCPU gets offlined. s390: - Fix false negatives in VSIE validity check (Cc stable) x86: - Fix time drift of VMX preemption timer when a guest uses LAPIC timer in periodic mode (Cc stable) - Unconditionally expose CPUID.IA32_ARCH_CAPABILITIES to allow migration from hosts that don't need retpoline mitigation (Cc stable) - Fix guest crashes on reboot by properly coupling CR4.OSXSAVE and CPUID.OSXSAVE (Cc stable) - Report correct RIP after Hyper-V hypercall #UD (introduced in -rc6)" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: x86: fix #UD address of failed Hyper-V hypercalls kvm: x86: IA32_ARCH_CAPABILITIES is always supported KVM: x86: Update cpuid properly when CR4.OSXAVE or CR4.PKE is changed x86/kvm: fix LAPIC timer drift when guest uses periodic mode KVM: s390: vsie: fix < 8k check for the itdba KVM: PPC: Book 3S HV: Do ptesync in radix guest exit path KVM: PPC: Book3S HV: XIVE: Resend re-routed interrupts on CPU priority change KVM: PPC: Book3S HV: Make radix clear pte when unmapping KVM: PPC: Book3S HV: Make radix use correct tlbie sequence in kvmppc_radix_tlbie_page KVM: PPC: Book3S HV: Snapshot timebase offset on guest entry
2018-05-26arm64: dts: hikey: Fix eMMC corruption regressionJohn Stultz
This patch is a partial revert of commit abd7d0972a19 ("arm64: dts: hikey: Enable HS200 mode on eMMC") which has been causing eMMC corruption on my HiKey board. Symptoms usually looked like: mmc_host mmc0: Bus speed (slot 0) = 24800000Hz (slot req 400000Hz, actual 400000HZ div = 31) ... mmc_host mmc0: Bus speed (slot 0) = 148800000Hz (slot req 150000000Hz, actual 148800000HZ div = 0) mmc0: new HS200 MMC card at address 0001 ... dwmmc_k3 f723d000.dwmmc0: Unexpected command timeout, state 3 mmc_host mmc0: Bus speed (slot 0) = 24800000Hz (slot req 400000Hz, actual 400000HZ div = 31) mmc_host mmc0: Bus speed (slot 0) = 148800000Hz (slot req 150000000Hz, actual 148800000HZ div = 0) mmc_host mmc0: Bus speed (slot 0) = 24800000Hz (slot req 400000Hz, actual 400000HZ div = 31) mmc_host mmc0: Bus speed (slot 0) = 148800000Hz (slot req 150000000Hz, actual 148800000HZ div = 0) mmc_host mmc0: Bus speed (slot 0) = 24800000Hz (slot req 400000Hz, actual 400000HZ div = 31) mmc_host mmc0: Bus speed (slot 0) = 148800000Hz (slot req 150000000Hz, actual 148800000HZ div = 0) print_req_error: I/O error, dev mmcblk0, sector 8810504 Aborting journal on device mmcblk0p10-8. mmc_host mmc0: Bus speed (slot 0) = 24800000Hz (slot req 400000Hz, actual 400000HZ div = 31) mmc_host mmc0: Bus speed (slot 0) = 148800000Hz (slot req 150000000Hz, actual 148800000HZ div = 0) mmc_host mmc0: Bus speed (slot 0) = 24800000Hz (slot req 400000Hz, actual 400000HZ div = 31) mmc_host mmc0: Bus speed (slot 0) = 148800000Hz (slot req 150000000Hz, actual 148800000HZ div = 0) mmc_host mmc0: Bus speed (slot 0) = 24800000Hz (slot req 400000Hz, actual 400000HZ div = 31) mmc_host mmc0: Bus speed (slot 0) = 148800000Hz (slot req 150000000Hz, actual 148800000HZ div = 0) mmc_host mmc0: Bus speed (slot 0) = 24800000Hz (slot req 400000Hz, actual 400000HZ div = 31) mmc_host mmc0: Bus speed (slot 0) = 148800000Hz (slot req 150000000Hz, actual 148800000HZ div = 0) EXT4-fs error (device mmcblk0p10): ext4_journal_check_start:61: Detected aborted journal EXT4-fs (mmcblk0p10): Remounting filesystem read-only And quite often this would result in a disk that wouldn't properly boot even with older kernels. It seems the max-frequency property added by the above patch is causing the problem, so remove it. Cc: Ryan Grachek <ryan@edited.us> Cc: Wei Xu <xuwei5@hisilicon.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Ulf Hansson <ulf.hansson@linaro.org> Cc: YongQin Liu <yongqin.liu@linaro.org> Cc: Leo Yan <leo.yan@linaro.org> Signed-off-by: John Stultz <john.stultz@linaro.org> Tested-by: Leo Yan <leo.yan@linaro.org> Signed-off-by: Wei Xu <xuwei04@gmail.com>
2018-05-26crypto: inside-secure - do not use memset on MMIOAntoine Tenart
This patch fixes the Inside Secure driver which uses a memtset() call to set an MMIO area from the cryptographic engine to 0. This is wrong as memset() isn't guaranteed to work on MMIO for many reasons. This led to kernel paging request panics in certain cases. Use memset_io() instead. Fixes: 1b44c5a60c13 ("crypto: inside-secure - add SafeXcel EIP197 crypto engine driver") Reported-by: Ofer Heifetz <oferh@marvell.com> Signed-off-by: Antoine Tenart <antoine.tenart@bootlin.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-05-26Documentation: filesystems: update filesystem locking documentationSean Anderson
Documentation/filesystems/Locking no longer reflects current locking semantics. i_mutex is no longer used for locking, and has been superseded by i_rwsem. Additionally, ->iterate_shared() was not documented. Signed-off-by: Sean Anderson <seanga2@gmail.com> Reviewed-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-05-26random: convert to ->poll_maskChristoph Hellwig
The big change is that random_read_wait and random_write_wait are merged into a single waitqueue that uses keyed wakeups. Because wait_event_* doesn't know about that this will lead to occassional spurious wakeups in _random_read and add_hwgenerator_randomness, but wait_event_* is designed to handle these and were are not in a a hot path there. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-26timerfd: convert to ->poll_maskChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-26eventfd: switch to ->poll_maskChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-26pipe: convert to ->poll_maskChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-26crypto: af_alg: convert to ->poll_maskChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-26net/rxrpc: convert to ->poll_maskChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-26net/iucv: convert to ->poll_maskChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-26net/phonet: convert to ->poll_maskChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-26net/nfc: convert to ->poll_maskChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-26net/caif: convert to ->poll_maskChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-26net/bluetooth: convert to ->poll_maskChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-26net/sctp: convert to ->poll_maskChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-26net/tipc: convert to ->poll_maskChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-26net/vmw_vsock: convert to ->poll_maskChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-26net/atm: convert to ->poll_maskChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-26net/dccp: convert to ->poll_maskChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-26net: convert datagram_poll users tp ->poll_maskChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-26net/unix: convert to ->poll_maskChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-26net/tcp: convert to ->poll_maskChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-26net: remove sock_no_pollChristoph Hellwig
Now that sock_poll handles a NULL ->poll or ->poll_mask there is no need for a stub. Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-26net: add support for ->poll_mask in proto_opsChristoph Hellwig
The socket file operations still implement ->poll until all protocols are switched over. Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-26net: refactor socket_pollChristoph Hellwig
Factor out two busy poll related helpers for late reuse, and remove a command that isn't very helpful, especially with the __poll_t annotations in place. Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-26aio: try to complete poll iocbs without context switchChristoph Hellwig
If we can acquire ctx_lock without spinning we can just remove our iocb from the active_reqs list, and thus complete the iocbs from the wakeup context. Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-26aio: implement IOCB_CMD_POLLChristoph Hellwig
Simple one-shot poll through the io_submit() interface. To poll for a file descriptor the application should submit an iocb of type IOCB_CMD_POLL. It will poll the fd for the events specified in the the first 32 bits of the aio_buf field of the iocb. Unlike poll or epoll without EPOLLONESHOT this interface always works in one shot mode, that is once the iocb is completed, it will have to be resubmitted. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-05-26aio: simplify cancellationChristoph Hellwig
With the current aio code there is no need for the magic KIOCB_CANCELLED value, as a cancelation just kicks the driver to queue the completion ASAP, with all actual completion handling done in another thread. Given that both the completion path and cancelation take the context lock there is no need for magic cmpxchg loops either. If we remove iocbs from the active list after calling ->ki_cancel (but with ctx_lock still held), we can also rely on the invariant thay anything found on the list has a ->ki_cancel callback and can be cancelled, further simplifing the code. Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-26aio: simplify KIOCB_KEY handlingChristoph Hellwig
No need to pass the key field to lookup_iocb to compare it with KIOCB_KEY, as we can do that right after retrieving it from userspace. Also move the KIOCB_KEY definition to aio.c as it is an internal value not used by any other place in the kernel. Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-26fs: introduce new ->get_poll_head and ->poll_mask methodsChristoph Hellwig
->get_poll_head returns the waitqueue that the poll operation is going to sleep on. Note that this means we can only use a single waitqueue for the poll, unlike some current drivers that use two waitqueues for different events. But now that we have keyed wakeups and heavily use those for poll there aren't that many good reason left to keep the multiple waitqueues, and if there are any ->poll is still around, the driver just won't support aio poll. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-05-26fs: add new vfs_poll and file_can_poll helpersChristoph Hellwig
These abstract out calls to the poll method in preparation for changes in how we poll. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-05-26fs: update documentation to mention __poll_t and match the codeChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-26fs: cleanup do_pollfdChristoph Hellwig
Use straightline code with failure handling gotos instead of a lot of nested conditionals. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-05-26fs: unexport poll_schedule_timeoutChristoph Hellwig
No users outside of select.c. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-05-26uapi: turn __poll_t sparse checks on by defaultChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-26Merge branch 'fixes' of ↵Christoph Hellwig
https://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs into aio-base
2018-05-26hwtracing: stm: fix build error on some archesGreg Kroah-Hartman
Commit b5e2ced9bf81 ("stm class: Use vmalloc for the master map") caused a build error on some arches as vmalloc.h was not explicitly included. Fix that by adding it to the list of includes. Fixes: b5e2ced9bf81 ("stm class: Use vmalloc for the master map") Reported-by: kbuild test robot <lkp@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-25Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge misc fixes from Andrew Morton: "16 fixes" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: kasan: fix memory hotplug during boot kasan: free allocated shadow memory on MEM_CANCEL_ONLINE checkpatch: fix macro argument precedence test init/main.c: include <linux/mem_encrypt.h> kernel/sys.c: fix potential Spectre v1 issue mm/memory_hotplug: fix leftover use of struct page during hotplug proc: fix smaps and meminfo alignment mm: do not warn on offline nodes unless the specific node is explicitly requested mm, memory_hotplug: make has_unmovable_pages more robust mm/kasan: don't vfree() nonexistent vm_area MAINTAINERS: change hugetlbfs maintainer and update files ipc/shm: fix shmat() nil address after round-down when remapping Revert "ipc/shm: Fix shmat mmap nil-page protection" idr: fix invalid ptr dereference on item delete ocfs2: revert "ocfs2/o2hb: check len for bio_add_page() to avoid getting incorrect bio" mm: fix nr_rotate_swap leak in swapon() error case
2018-05-25Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netLinus Torvalds
Pull networking fixes from David Miller: "Let's begin the holiday weekend with some networking fixes: 1) Whoops need to restrict cfg80211 wiphy names even more to 64 bytes. From Eric Biggers. 2) Fix flags being ignored when using kernel_connect() with SCTP, from Xin Long. 3) Use after free in DCCP, from Alexey Kodanev. 4) Need to check rhltable_init() return value in ipmr code, from Eric Dumazet. 5) XDP handling fixes in virtio_net from Jason Wang. 6) Missing RTA_TABLE in rtm_ipv4_policy[], from Roopa Prabhu. 7) Need to use IRQ disabling spinlocks in mlx4_qp_lookup(), from Jack Morgenstein. 8) Prevent out-of-bounds speculation using indexes in BPF, from Daniel Borkmann. 9) Fix regression added by AF_PACKET link layer cure, from Willem de Bruijn. 10) Correct ENIC dma mask, from Govindarajulu Varadarajan. 11) Missing config options for PMTU tests, from Stefano Brivio" * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (48 commits) ibmvnic: Fix partial success login retries selftests/net: Add missing config options for PMTU tests mlx4_core: allocate ICM memory in page size chunks enic: set DMA mask to 47 bit ppp: remove the PPPIOCDETACH ioctl ipv4: remove warning in ip_recv_error net : sched: cls_api: deal with egdev path only if needed vhost: synchronize IOTLB message with dev cleanup packet: fix reserve calculation net/mlx5: IPSec, Fix a race between concurrent sandbox QP commands net/mlx5e: When RXFCS is set, add FCS data into checksum calculation bpf: properly enforce index mask to prevent out-of-bounds speculation net/mlx4: Fix irq-unsafe spinlock usage net: phy: broadcom: Fix bcm_write_exp() net: phy: broadcom: Fix auxiliary control register reads net: ipv4: add missing RTA_TABLE to rtm_ipv4_policy net/mlx4: fix spelling mistake: "Inrerface" -> "Interface" and rephrase message ibmvnic: Only do H_EOI for mobility events tuntap: correctly set SOCKWQ_ASYNC_NOSPACE virtio-net: fix leaking page for gso packet during mergeable XDP ...
2018-05-25kasan: fix memory hotplug during bootDavid Hildenbrand
Using module_init() is wrong. E.g. ACPI adds and onlines memory before our memory notifier gets registered. This makes sure that ACPI memory detected during boot up will not result in a kernel crash. Easily reproducible with QEMU, just specify a DIMM when starting up. Link: http://lkml.kernel.org/r/20180522100756.18478-3-david@redhat.com Fixes: 786a8959912e ("kasan: disable memory hotplug") Signed-off-by: David Hildenbrand <david@redhat.com> Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Alexander Potapenko <glider@google.com> Cc: Dmitry Vyukov <dvyukov@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>