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2017-05-23arm: Adjust system_state checkThomas Gleixner
To enable smp_processor_id() and might_sleep() debug checks earlier, it's required to add system states between SYSTEM_BOOTING and SYSTEM_RUNNING. Adjust the system_state check in ipi_cpu_stop() to handle the extra states. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: linux-arm-kernel@lists.infradead.org Link: http://lkml.kernel.org/r/20170516184735.020718977@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-03sched/headers: Move task->mm handling methods to <linux/sched/mm.h>Ingo Molnar
Move the following task->mm helper APIs into a new header file, <linux/sched/mm.h>, to further reduce the size and complexity of <linux/sched.h>. Here are how the APIs are used in various kernel files: # mm_alloc(): arch/arm/mach-rpc/ecard.c fs/exec.c include/linux/sched/mm.h kernel/fork.c # __mmdrop(): arch/arc/include/asm/mmu_context.h include/linux/sched/mm.h kernel/fork.c # mmdrop(): arch/arm/mach-rpc/ecard.c arch/m68k/sun3/mmu_emu.c arch/x86/mm/tlb.c drivers/gpu/drm/amd/amdkfd/kfd_process.c drivers/gpu/drm/i915/i915_gem_userptr.c drivers/infiniband/hw/hfi1/file_ops.c drivers/vfio/vfio_iommu_spapr_tce.c fs/exec.c fs/proc/base.c fs/proc/task_mmu.c fs/proc/task_nommu.c fs/userfaultfd.c include/linux/mmu_notifier.h include/linux/sched/mm.h kernel/fork.c kernel/futex.c kernel/sched/core.c mm/khugepaged.c mm/ksm.c mm/mmu_context.c mm/mmu_notifier.c mm/oom_kill.c virt/kvm/kvm_main.c # mmdrop_async_fn(): include/linux/sched/mm.h # mmdrop_async(): include/linux/sched/mm.h kernel/fork.c # mmget_not_zero(): fs/userfaultfd.c include/linux/sched/mm.h mm/oom_kill.c # mmput(): arch/arc/include/asm/mmu_context.h arch/arc/kernel/troubleshoot.c arch/frv/mm/mmu-context.c arch/powerpc/platforms/cell/spufs/context.c arch/sparc/include/asm/mmu_context_32.h drivers/android/binder.c drivers/gpu/drm/etnaviv/etnaviv_gem.c drivers/gpu/drm/i915/i915_gem_userptr.c drivers/infiniband/core/umem.c drivers/infiniband/core/umem_odp.c drivers/infiniband/core/uverbs_main.c drivers/infiniband/hw/mlx4/main.c drivers/infiniband/hw/mlx5/main.c drivers/infiniband/hw/usnic/usnic_uiom.c drivers/iommu/amd_iommu_v2.c drivers/iommu/intel-svm.c drivers/lguest/lguest_user.c drivers/misc/cxl/fault.c drivers/misc/mic/scif/scif_rma.c drivers/oprofile/buffer_sync.c drivers/vfio/vfio_iommu_type1.c drivers/vhost/vhost.c drivers/xen/gntdev.c fs/exec.c fs/proc/array.c fs/proc/base.c fs/proc/task_mmu.c fs/proc/task_nommu.c fs/userfaultfd.c include/linux/sched/mm.h kernel/cpuset.c kernel/events/core.c kernel/events/uprobes.c kernel/exit.c kernel/fork.c kernel/ptrace.c kernel/sys.c kernel/trace/trace_output.c kernel/tsacct.c mm/memcontrol.c mm/memory.c mm/mempolicy.c mm/migrate.c mm/mmu_notifier.c mm/nommu.c mm/oom_kill.c mm/process_vm_access.c mm/rmap.c mm/swapfile.c mm/util.c virt/kvm/async_pf.c # mmput_async(): include/linux/sched/mm.h kernel/fork.c mm/oom_kill.c # get_task_mm(): arch/arc/kernel/troubleshoot.c arch/powerpc/platforms/cell/spufs/context.c drivers/android/binder.c drivers/gpu/drm/etnaviv/etnaviv_gem.c drivers/infiniband/core/umem.c drivers/infiniband/core/umem_odp.c drivers/infiniband/hw/mlx4/main.c drivers/infiniband/hw/mlx5/main.c drivers/infiniband/hw/usnic/usnic_uiom.c drivers/iommu/amd_iommu_v2.c drivers/iommu/intel-svm.c drivers/lguest/lguest_user.c drivers/misc/cxl/fault.c drivers/misc/mic/scif/scif_rma.c drivers/oprofile/buffer_sync.c drivers/vfio/vfio_iommu_type1.c drivers/vhost/vhost.c drivers/xen/gntdev.c fs/proc/array.c fs/proc/base.c fs/proc/task_mmu.c include/linux/sched/mm.h kernel/cpuset.c kernel/events/core.c kernel/exit.c kernel/fork.c kernel/ptrace.c kernel/sys.c kernel/trace/trace_output.c kernel/tsacct.c mm/memcontrol.c mm/memory.c mm/mempolicy.c mm/migrate.c mm/mmu_notifier.c mm/nommu.c mm/util.c # mm_access(): fs/proc/base.c include/linux/sched/mm.h kernel/fork.c mm/process_vm_access.c # mm_release(): arch/arc/include/asm/mmu_context.h fs/exec.c include/linux/sched/mm.h include/uapi/linux/sched.h kernel/exit.c kernel/fork.c Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02sched/headers: Prepare for new header dependencies before moving code to ↵Ingo Molnar
<linux/sched/task_stack.h> We are going to split <linux/sched/task_stack.h> out of <linux/sched.h>, which will have to be picked up from other headers and a couple of .c files. Create a trivial placeholder <linux/sched/task_stack.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02sched/headers: Prepare for new header dependencies before moving code to ↵Ingo Molnar
<linux/sched/hotplug.h> We are going to split <linux/sched/hotplug.h> out of <linux/sched.h>, which will have to be picked up from other headers and a couple of .c files. Create a trivial placeholder <linux/sched/hotplug.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-02-28Merge branch 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-armLinus Torvalds
Pull ARM updates from Russell King: - nommu updates from Afzal Mohammed cleaning up the vectors support - allow DMA memory "mapping" for nommu Benjamin Gaignard - fixing a correctness issue with R_ARM_PREL31 relocations in the module linker - add strlen() prototype for the decompressor - support for DEBUG_VIRTUAL from Florian Fainelli - adjusting memory bounds after memory reservations have been registered - unipher cache handling updates from Masahiro Yamada - initrd and Thumb Kconfig cleanups * 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm: (23 commits) ARM: mm: round the initrd reservation to page boundaries ARM: mm: clean up initrd initialisation ARM: mm: move initrd init code out of arm_memblock_init() ARM: 8655/1: improve NOMMU definition of pgprot_*() ARM: 8654/1: decompressor: add strlen prototype ARM: 8652/1: cache-uniphier: clean up active way setup code ARM: 8651/1: cache-uniphier: include <linux/errno.h> instead of <linux/types.h> ARM: 8650/1: module: handle negative R_ARM_PREL31 addends correctly ARM: 8649/2: nommu: remove Hivecs configuration is asm ARM: 8648/2: nommu: display vectors base ARM: 8647/2: nommu: dynamic exception base address setting ARM: 8646/1: mmu: decouple VECTORS_BASE from Kconfig ARM: 8644/1: Reduce "CPU: shutdown" message to debug level ARM: 8641/1: treewide: Replace uses of virt_to_phys with __pa_symbol ARM: 8640/1: Add support for CONFIG_DEBUG_VIRTUAL ARM: 8639/1: Define KERNEL_START and KERNEL_END ARM: 8638/1: mtd: lart: Rename partition defines to be prefixed with PART_ ARM: 8637/1: Adjust memory boundaries after reservations ARM: 8636/1: Cleanup sanity_check_meminfo ARM: add CPU_THUMB_CAPABLE to indicate possible Thumb support ...
2017-02-28ARM: 8644/1: Reduce "CPU: shutdown" message to debug levelFlorian Fainelli
Similar to c68b0274fb3c ("ARM: reduce "Booted secondary processor" message to debug level"), demote the "CPU: shutdown" pr_notice() into a pr_debug(). Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2017-02-27mm: add new mmgrab() helperVegard Nossum
Apart from adding the helper function itself, the rest of the kernel is converted mechanically using: git grep -l 'atomic_inc.*mm_count' | xargs sed -i 's/atomic_inc(&\(.*\)->mm_count);/mmgrab\(\1\);/' git grep -l 'atomic_inc.*mm_count' | xargs sed -i 's/atomic_inc(&\(.*\)\.mm_count);/mmgrab\(\&\1\);/' This is needed for a later patch that hooks into the helper, but might be a worthwhile cleanup on its own. (Michal Hocko provided most of the kerneldoc comment.) Link: http://lkml.kernel.org/r/20161218123229.22952-1-vegard.nossum@oracle.com Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-07nmi_backtrace: do a local dump_stack() instead of a self-NMIChris Metcalf
Currently on arm there is code that checks whether it should call dump_stack() explicitly, to avoid trying to raise an NMI when the current context is not preemptible by the backtrace IPI. Similarly, the forthcoming arch/tile support uses an IPI mechanism that does not support generating an NMI to self. Accordingly, move the code that guards this case into the generic mechanism, and invoke it unconditionally whenever we want a backtrace of the current cpu. It seems plausible that in all cases, dump_stack() will generate better information than generating a stack from the NMI handler. The register state will be missing, but that state is likely not particularly helpful in any case. Or, if we think it is helpful, we should be capturing and emitting the current register state in all cases when regs == NULL is passed to nmi_cpu_backtrace(). Link: http://lkml.kernel.org/r/1472487169-14923-3-git-send-email-cmetcalf@mellanox.com Signed-off-by: Chris Metcalf <cmetcalf@mellanox.com> Tested-by: Daniel Thompson <daniel.thompson@linaro.org> [arm] Reviewed-by: Petr Mladek <pmladek@suse.com> Acked-by: Aaron Tomlin <atomlin@redhat.com> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Russell King <linux@arm.linux.org.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-07nmi_backtrace: add more trigger_*_cpu_backtrace() methodsChris Metcalf
Patch series "improvements to the nmi_backtrace code" v9. This patch series modifies the trigger_xxx_backtrace() NMI-based remote backtracing code to make it more flexible, and makes a few small improvements along the way. The motivation comes from the task isolation code, where there are scenarios where we want to be able to diagnose a case where some cpu is about to interrupt a task-isolated cpu. It can be helpful to see both where the interrupting cpu is, and also an approximation of where the cpu that is being interrupted is. The nmi_backtrace framework allows us to discover the stack of the interrupted cpu. I've tested that the change works as desired on tile, and build-tested x86, arm, mips, and sparc64. For x86 I confirmed that the generic cpuidle stuff as well as the architecture-specific routines are in the new cpuidle section. For arm, mips, and sparc I just build-tested it and made sure the generic cpuidle routines were in the new cpuidle section, but I didn't attempt to figure out which the platform-specific idle routines might be. That might be more usefully done by someone with platform experience in follow-up patches. This patch (of 4): Currently you can only request a backtrace of either all cpus, or all cpus but yourself. It can also be helpful to request a remote backtrace of a single cpu, and since we want that, the logical extension is to support a cpumask as the underlying primitive. This change modifies the existing lib/nmi_backtrace.c code to take a cpumask as its basic primitive, and modifies the linux/nmi.h code to use the new "cpumask" method instead. The existing clients of nmi_backtrace (arm and x86) are converted to using the new cpumask approach in this change. The other users of the backtracing API (sparc64 and mips) are converted to use the cpumask approach rather than the all/allbutself approach. The mips code ignored the "include_self" boolean but with this change it will now also dump a local backtrace if requested. Link: http://lkml.kernel.org/r/1472487169-14923-2-git-send-email-cmetcalf@mellanox.com Signed-off-by: Chris Metcalf <cmetcalf@mellanox.com> Tested-by: Daniel Thompson <daniel.thompson@linaro.org> [arm] Reviewed-by: Aaron Tomlin <atomlin@redhat.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Russell King <linux@arm.linux.org.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: David Miller <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-12ARM: 8595/2: apply more __ro_after_initKees Cook
Guided by grsecurity's analogous __read_only markings in arch/arm, this applies several uses of __ro_after_init to structures that are only updated during __init. Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2016-06-18Merge tag 'fixes-rcu-fiq-signed' of ↵Olof Johansson
git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap into fixes Fixes for omaps for v4.7-rc cycle: - Two boot warning fixes from the RCU tree that should have gotten merged several weeks ago already but did not because of issues with who merges them. Paul has now split the RCU warning fixes into sets for various maintainers. - Fix ams-delta FIQ regression caused by omap1 sparse IRQ changes - Fix PM for omap3 boards using timer12 and gptimer, like the original beagleboard - Fix hangs on am437x-sk-evm by lowering the I2C bus speed * tag 'fixes-rcu-fiq-signed' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap: ARM: dts: am437x-sk-evm: Reduce i2c0 bus speed for tps65218 ARM: OMAP2+: timer: add probe for clocksources ARM: OMAP1: fix ams-delta FIQ handler to work with sparse IRQ arm: Use _rcuidle for smp_cross_call() tracepoints arm: Use _rcuidle tracepoint to allow use from idle Signed-off-by: Olof Johansson <olof@lixom.net>
2016-06-14arm: Use _rcuidle for smp_cross_call() tracepointsPaul E. McKenney
Further testing with false negatives suppressed by commit 293e2421fe25 ("rcu: Remove superfluous versions of rcu_read_lock_sched_held()") identified another unprotected use of RCU from the idle loop. Because RCU actively ignores idle-loop code (for energy-efficiency reasons, among other things), using RCU from the idle loop can result in too-short grace periods, in turn resulting in arbitrary misbehavior. The resulting lockdep-RCU splat is as follows: ------------------------------------------------------------------------ =============================== [ INFO: suspicious RCU usage. ] 4.6.0-rc5-next-20160426+ #1112 Not tainted ------------------------------- include/trace/events/ipi.h:35 suspicious rcu_dereference_check() usage! other info that might help us debug this: RCU used illegally from idle CPU! rcu_scheduler_active = 1, debug_locks = 0 RCU used illegally from extended quiescent state! no locks held by swapper/0/0. stack backtrace: CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.6.0-rc5-next-20160426+ #1112 Hardware name: Generic OMAP4 (Flattened Device Tree) [<c0110308>] (unwind_backtrace) from [<c010c3a8>] (show_stack+0x10/0x14) [<c010c3a8>] (show_stack) from [<c047fec8>] (dump_stack+0xb0/0xe4) [<c047fec8>] (dump_stack) from [<c010dcfc>] (smp_cross_call+0xbc/0x188) [<c010dcfc>] (smp_cross_call) from [<c01c9e28>] (generic_exec_single+0x9c/0x15c) [<c01c9e28>] (generic_exec_single) from [<c01ca0a0>] (smp_call_function_single_async+0 x38/0x9c) [<c01ca0a0>] (smp_call_function_single_async) from [<c0603728>] (cpuidle_coupled_poke_others+0x8c/0xa8) [<c0603728>] (cpuidle_coupled_poke_others) from [<c0603c10>] (cpuidle_enter_state_coupled+0x26c/0x390) [<c0603c10>] (cpuidle_enter_state_coupled) from [<c0183c74>] (cpu_startup_entry+0x198/0x3a0) [<c0183c74>] (cpu_startup_entry) from [<c0b00c0c>] (start_kernel+0x354/0x3c8) [<c0b00c0c>] (start_kernel) from [<8000807c>] (0x8000807c) ------------------------------------------------------------------------ Reported-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Tested-by: Tony Lindgren <tony@atomide.com> Tested-by: Guenter Roeck <linux@roeck-us.net> Cc: Russell King <linux@arm.linux.org.uk> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: <linux-omap@vger.kernel.org> Cc: <linux-arm-kernel@lists.infradead.org>
2016-05-20printk/nmi: generic solution for safe printk in NMIPetr Mladek
printk() takes some locks and could not be used a safe way in NMI context. The chance of a deadlock is real especially when printing stacks from all CPUs. This particular problem has been addressed on x86 by the commit a9edc8809328 ("x86/nmi: Perform a safe NMI stack trace on all CPUs"). The patchset brings two big advantages. First, it makes the NMI backtraces safe on all architectures for free. Second, it makes all NMI messages almost safe on all architectures (the temporary buffer is limited. We still should keep the number of messages in NMI context at minimum). Note that there already are several messages printed in NMI context: WARN_ON(in_nmi()), BUG_ON(in_nmi()), anything being printed out from MCE handlers. These are not easy to avoid. This patch reuses most of the code and makes it generic. It is useful for all messages and architectures that support NMI. The alternative printk_func is set when entering and is reseted when leaving NMI context. It queues IRQ work to copy the messages into the main ring buffer in a safe context. __printk_nmi_flush() copies all available messages and reset the buffer. Then we could use a simple cmpxchg operations to get synchronized with writers. There is also used a spinlock to get synchronized with other flushers. We do not longer use seq_buf because it depends on external lock. It would be hard to make all supported operations safe for a lockless use. It would be confusing and error prone to make only some operations safe. The code is put into separate printk/nmi.c as suggested by Steven Rostedt. It needs a per-CPU buffer and is compiled only on architectures that call nmi_enter(). This is achieved by the new HAVE_NMI Kconfig flag. The are MN10300 and Xtensa architectures. We need to clean up NMI handling there first. Let's do it separately. The patch is heavily based on the draft from Peter Zijlstra, see https://lkml.org/lkml/2015/6/10/327 [arnd@arndb.de: printk-nmi: use %zu format string for size_t] [akpm@linux-foundation.org: min_t->min - all types are size_t here] Signed-off-by: Petr Mladek <pmladek@suse.com> Suggested-by: Peter Zijlstra <peterz@infradead.org> Suggested-by: Steven Rostedt <rostedt@goodmis.org> Cc: Jan Kara <jack@suse.cz> Acked-by: Russell King <rmk+kernel@arm.linux.org.uk> [arm part] Cc: Daniel Thompson <daniel.thompson@linaro.org> Cc: Jiri Kosina <jkosina@suse.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: David Miller <davem@davemloft.net> Cc: Daniel Thompson <daniel.thompson@linaro.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-01arch/hotplug: Call into idle with a proper stateThomas Gleixner
Let the non boot cpus call into idle with the corresponding hotplug state, so the hotplug core can handle the further bringup. That's a first step to convert the boot side of the hotplugged cpus to do all the synchronization with the other side through the state machine. For now it'll only start the hotplug thread and kick the full bringup of the cpu. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: linux-arch@vger.kernel.org Cc: Rik van Riel <riel@redhat.com> Cc: Rafael Wysocki <rafael.j.wysocki@intel.com> Cc: "Srivatsa S. Bhat" <srivatsa@mit.edu> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Sebastian Siewior <bigeasy@linutronix.de> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Tejun Heo <tj@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Paul McKenney <paulmck@linux.vnet.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul Turner <pjt@google.com> Link: http://lkml.kernel.org/r/20160226182341.614102639@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-12-22ARM: 8488/1: Make IPI_CPU_BACKTRACE a "non-secure" SGIMarc Zyngier
Having IPI_CPU_BACKTRACE as SGI15 may not work if the kernel is running in non-secure mode and that the secure firmware has decided to follow ARM's recommendations that SGI8-15 should be reserved for secure purpose. Now that we are "only" using SGI0-6, change IPI_CPU_BACKTRACE to use SGI7, which makes it more likely to work. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-12-22ARM: 8487/1: Remove IPI_CALL_FUNC_SINGLEMarc Zyngier
Since 9a46ad6d6df3 ("smp: make smp_call_function_many() use logic similar to smp_call_function_single()"), the core IPI handling has been simplified, and generic_smp_call_function_interrupt is now the same as generic_smp_call_function_single_interrupt. This means that one of IPI_CALL_FUNC and IPI_CALL_FUNC_SINGLE has become redundant. We can then safely drop IPI_CALL_FUNC_SINGLE, and use only IPI_CALL_FUNC. This has the advantage of reducing the number of SGI IDs we're using (a fairly scarse resource). Tested on a dual A7 board. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-10-03ARM: 8439/1: Fix backtrace generation when IPI is maskedDaniel Thompson
Currently on ARM when <SysRq-L> is triggered from an interrupt handler (e.g. a SysRq issued using UART or kbd) the main CPU will wedge for ten seconds with interrupts masked before issuing a backtrace for every CPU except itself. The new backtrace code introduced by commit 96f0e00378d4 ("ARM: add basic support for on-demand backtrace of other CPUs") does not work correctly when run from an interrupt handler because IPI_CPU_BACKTRACE is used to generate the backtrace on all CPUs but cannot preempt the current calling context. This can be fixed by detecting that the calling context cannot be preempted and issuing the backtrace directly in this case. Issuing directly leaves us without any pt_regs to pass to nmi_cpu_backtrace() so we also modify the generic code to call dump_stack() when its argument is NULL. Acked-by: Hillf Danton <hillf.zj@alibaba-inc.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-09-22ARM: 8424/1: add const qualifier to the argument of smp_set_ops()Masahiro Yamada
This function just copies '*ops' to 'smp_ops', so the given structure '*ops' is not modified at all. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Acked-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-09-22ARM: 8422/1: enable imprecise aborts during early kernel startupLucas Stach
This patch adds imprecise abort enable/disable macros and uses them to enable imprecise aborts early when starting the kernel. This helps in tracking down the real cause for such imprecise abort, as they are handled as soon as they occur. Until now those aborts would only be enabled when entering the userspace and as a consequence crash the first userspace process if any abort had been raised during kernel startup. Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com> Signed-off-by: Lucas Stach <l.stach@pengutronix.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-09-08Merge branch 'nmi' of git://ftp.arm.linux.org.uk/~rmk/linux-armLinus Torvalds
Pull NMI backtrace update from Russell King: "These changes convert the x86 NMI handling to be a library implementation which other architectures can make use of. Thomas Gleixner has reviewed and tested these changes, and wishes me to send these rather than taking them through the tip tree. The final patch in the set adds an initial implementation using this infrastructure to ARM, even though it doesn't send the IPI at "NMI" level. Patches are in progress to add the ARM equivalent of NMI, but we still need the IRQ-level fallback for systems where the "NMI" isn't available due to secure firmware denying access to it" * 'nmi' of git://ftp.arm.linux.org.uk/~rmk/linux-arm: ARM: add basic support for on-demand backtrace of other CPUs nmi: x86: convert to generic nmi handler nmi: create generic NMI backtrace implementation
2015-09-03Merge branches 'cleanup', 'fixes', 'misc', 'omap-barrier' and 'uaccess' into ↵Russell King
for-linus
2015-08-25ARM: 8421/1: smp: Collapse arch_cpu_idle_dead() into cpu_die()Stephen Boyd
The only caller of cpu_die() on ARM is arch_cpu_idle_dead(), so let's simplify the code by renaming cpu_die() to arch_cpu_idle_dead(). While were here, drop the __ref annotation because __cpuinit is gone nowadays. Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-07-31ARM: 8392/3: smp: Only expose /sys/.../cpuX/online if hotpluggableStephen Boyd
Writes to /sys/.../cpuX/online fail if we determine the platform doesn't support hotplug for that CPU. Furthermore, if the cpu_die op isn't specified the system hangs when we try to offline a CPU and it comes right back online unexpectedly. Let's figure this stuff out before we make the sysfs nodes so that the online file doesn't even exist if it isn't (at least sometimes) possible to hotplug the CPU. Add a new 'cpu_can_disable' op and repoint all 'cpu_disable' implementations at it because all implementers use the op to indicate if a CPU can be hotplugged or not in a static fashion. With PSCI we may need to add a 'cpu_disable' op so that the secure OS can be migrated off the CPU we're trying to hotplug. In this case, the 'cpu_can_disable' op will indicate that all CPUs are hotpluggable by returning true, but the 'cpu_disable' op will make a PSCI migration call and occasionally fail, denying the hotplug of a CPU. This shouldn't be any worse than x86 where we may indicate that all CPUs are hotpluggable but occasionally we can't offline a CPU due to check_irq_vectors_for_cpu_disable() failing to find a CPU to move vectors to. Cc: Mark Rutland <mark.rutland@arm.com> Cc: Nicolas Pitre <nico@linaro.org> Cc: Dave Martin <Dave.Martin@arm.com> Acked-by: Simon Horman <horms@verge.net.au> [shmobile portion] Tested-by: Simon Horman <horms@verge.net.au> Cc: Magnus Damm <magnus.damm@gmail.com> Cc: <linux-sh@vger.kernel.org> Tested-by: Tyler Baker <tyler.baker@linaro.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-07-17ARM: add basic support for on-demand backtrace of other CPUsnmiRussell King
As we now have generic infrastructure to support backtracing of other CPUs in the system on lockups, we can start to implement this for ARM. Initially, we add an IPI based implementation, as the GIC code needs modification to support the generation of FIQ IPIs, and not all ARM platforms have the ability to raise a FIQ in the non-secure world. This provides us with a "best efforts" implementation in the absence of FIQs. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-07-07Merge branches 'fixes' and 'ioremap' into for-linusRussell King
2015-06-29ARM: 8393/1: smp: Fix suspicious RCU usage with ipi tracepointsStephen Boyd
John Stultz reports an RCU splat on boot with ARM ipi trace events enabled. =============================== [ INFO: suspicious RCU usage. ] 4.1.0-rc7-00033-gb5bed2f #153 Not tainted ------------------------------- include/trace/events/ipi.h:68 suspicious rcu_dereference_check() usage! other info that might help us debug this: RCU used illegally from idle CPU! rcu_scheduler_active = 1, debug_locks = 0 RCU used illegally from extended quiescent state! no locks held by swapper/0/0. stack backtrace: CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.1.0-rc7-00033-gb5bed2f #153 Hardware name: Qualcomm (Flattened Device Tree) [<c0216b08>] (unwind_backtrace) from [<c02136e8>] (show_stack+0x10/0x14) [<c02136e8>] (show_stack) from [<c075e678>] (dump_stack+0x70/0xbc) [<c075e678>] (dump_stack) from [<c0215a80>] (handle_IPI+0x428/0x604) [<c0215a80>] (handle_IPI) from [<c020942c>] (gic_handle_irq+0x54/0x5c) [<c020942c>] (gic_handle_irq) from [<c0766604>] (__irq_svc+0x44/0x7c) Exception stack(0xc09f3f48 to 0xc09f3f90) 3f40: 00000001 00000001 00000000 c09f73b8 c09f4528 c0a5de9c 3f60: c076b4f0 00000000 00000000 c09ef108 c0a5cec1 00000001 00000000 c09f3f90 3f80: c026bf60 c0210ab8 20000113 ffffffff [<c0766604>] (__irq_svc) from [<c0210ab8>] (arch_cpu_idle+0x20/0x3c) [<c0210ab8>] (arch_cpu_idle) from [<c02647f0>] (cpu_startup_entry+0x2c0/0x5dc) [<c02647f0>] (cpu_startup_entry) from [<c099bc1c>] (start_kernel+0x358/0x3c4) [<c099bc1c>] (start_kernel) from [<8020807c>] (0x8020807c) At this point in the IPI handling path we haven't called irq_enter() yet, so RCU doesn't know that we're about to exit idle and properly warns that we're using RCU from an idle CPU. Use trace_ipi_entry_rcuidle() instead of trace_ipi_entry() so that RCU is informed about our exit from idle. Fixes: 365ec7b17327 ("ARM: add IPI tracepoints") Reported-by: John Stultz <john.stultz@linaro.org> Tested-by: John Stultz <john.stultz@linaro.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-06-01ARM: redo TTBR setup code for LPAERussell King
Re-engineer the LPAE TTBR setup code. Rather than passing some shifted address in order to fit in a CPU register, pass either a full physical address (in the case of r4, r5 for TTBR0) or a PFN (for TTBR1). This removes the ARCH_PGD_SHIFT hack, and the last dangerous user of cpu_set_ttbr() in the secondary CPU startup code path (which was there to re-set TTBR1 to the appropriate high physical address space on Keystone2.) Tested-by: Murali Karicheri <m-karicheri2@ti.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-04-02ARM: 8338/1: kexec: Relax SMP validation to improve DT compatibilityGeert Uytterhoeven
When trying to kexec into a new kernel on a platform where multiple CPU cores are present, but no SMP bringup code is available yet, the kexec_load system call fails with: kexec_load failed: Invalid argument The SMP test added to machine_kexec_prepare() in commit 2103f6cba61a8b8b ("ARM: 7807/1: kexec: validate CPU hotplug support") wants to prohibit kexec on SMP platforms where it cannot disable secondary CPUs. However, this test is too strict: if the secondary CPUs couldn't be enabled in the first place, there's no need to disable them later at kexec time. Hence skip the test in the absence of SMP bringup code. This allows to add all CPU cores to the DTS from the beginning, without having to implement SMP bringup first, improving DT compatibility. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Acked-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-01-04Revert "ARM: 7830/1: delay: don't bother reporting bogomips in /proc/cpuinfo"Pavel Machek
Commit 9fc2105aeaaf ("ARM: 7830/1: delay: don't bother reporting bogomips in /proc/cpuinfo") breaks audio in python, and probably elsewhere, with message FATAL: cannot locate cpu MHz in /proc/cpuinfo I'm not the first one to hit it, see for example https://theredblacktree.wordpress.com/2014/08/10/fatal-cannot-locate-cpu-mhz-in-proccpuinfo/ https://devtalk.nvidia.com/default/topic/765800/workaround-for-fatal-cannot-locate-cpu-mhz-in-proc-cpuinf/?offset=1 Reading original changelog, I have to say "Stop breaking working setups. You know who you are!". Signed-off-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-11-21ARM: remove "SMP: Total of %d processors activated." messageRussell King
The "SMP: Total of %d processors activated." message which we print in smp_cpus_done() provides no further information than the message in genreic code in smp_announce(). Kill it. Tested-by: Felipe Balbi <balbi@ti.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-11-21ARM: reduce "Booted secondary processor" message to debug levelRussell King
Drop the "CPUn: Booted secondary processor" message from info to debug level. We later print how many CPUs came online, so listing each one is redundant, and when using hotplug, can be quite noisy. Tested-by: Felipe Balbi <balbi@ti.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-11-21ARM: convert printk(KERN_* to pr_*Russell King
Convert many (but not all) printk(KERN_* to pr_* to simplify the code. We take the opportunity to join some printk lines together so we don't split the message across several lines, and we also add a few levels to some messages which were previously missing them. Tested-by: Andrew Lunn <andrew@lunn.ch> Tested-by: Felipe Balbi <balbi@ti.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-10-09Merge branch 'timers-nohz-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer fixes from Ingo Molnar: "Main changes: - Fix the deadlock reported by Dave Jones et al - Clean up and fix nohz_full interaction with arch abilities - nohz init code consolidation/cleanup" * 'timers-nohz-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: nohz: nohz full depends on irq work self IPI support nohz: Consolidate nohz full init code arm64: Tell irq work about self IPI support arm: Tell irq work about self IPI support x86: Tell irq work about self IPI support irq_work: Force raised irq work to run on irq work interrupt irq_work: Introduce arch_irq_work_has_interrupt() nohz: Move nohz full init call to tick init
2014-09-26ARM: 8152/1: Convert pr_warning to pr_warnJoe Perches
Use the more common pr_warn. Other miscellanea: o Coalesce formats o Realign arguments Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-09-13arm: Tell irq work about self IPI supportFrederic Weisbecker
ARM irq work IPI support depends on SMP support. That information is partly known at early boottime. Lets implement arch_irq_work_has_interrupt() accordingly. Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2014-08-27ARM: 8131/1: arm/smp: Absorb boot_secondary()Geert Uytterhoeven
After becoming a mandatory function, boot_secondary() is no longer used outside arch/arm/kernel/smp.c. Hence remove its public prototype, and, as suggested by Arnd, let it be absorbed by its single caller. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-08-07ARM: add IPI tracepointsNicolas Pitre
The strings used to list IPIs in /proc/interrupts are reused for tracing purposes. While at it, prevent a negative ipinr from escaping the range check in handle_IPI(). Link: http://lkml.kernel.org/p/1406318733-26754-4-git-send-email-nicolas.pitre@linaro.org Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-03-19cpufreq: remove unused notifier: CPUFREQ_{SUSPENDCHANGE|RESUMECHANGE}Viresh Kumar
Two cpufreq notifiers CPUFREQ_RESUMECHANGE and CPUFREQ_SUSPENDCHANGE have not been used for some time, so remove them to clean up code a bit. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> [rjw: Changelog] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-01-21ARM: SMP implementations are not supposed to return from smp_ops.cpu_die()Russell King
Although we allow recovery in this case, this is not supposed to be the normal path for hotplugging a CPU back in. This path only exists to serve those rare platforms where it's not possible to power down the CPU or reset the CPU. This patch causes the kernel to print a message when a platform uses this path. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-12-29ARM: 7918/1: clean up cache handling in core codeNicolas Pitre
We have a handy macro to replace open coded __cpuc_flush_dcache_area(() and outer_clean_range() sequences. Let's use it. No functional change. Signed-off-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-11-12Merge branch 'devel-stable' into for-nextRussell King
Conflicts: arch/arm/include/asm/atomic.h arch/arm/include/asm/hardirq.h arch/arm/kernel/smp.c
2013-11-09ARM: 7887/1: Don't smp_cross_call() on UP devices in arch_irq_work_raise()Stephen Boyd
If we're running a kernel compiled with SMP_ON_UP=y and the hardware only supports UP operation there isn't any smp_cross_call function assigned. Unfortunately, we call smp_cross_call() unconditionally in arch_irq_work_raise() and crash the kernel on UP devices. Check to make sure we're running on an SMP device before calling smp_cross_call() here. Unable to handle kernel NULL pointer dereference at virtual address 00000000 pgd = c0004000 [00000000] *pgd=00000000 Internal error: Oops: 80000005 [#1] SMP ARM Modules linked in: CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.12.0-rc6-00018-g8d45144-dirty #16 task: de05b440 ti: de05c000 task.ti: de05c000 PC is at 0x0 LR is at arch_irq_work_raise+0x3c/0x48 pc : [<00000000>] lr : [<c0019590>] psr: 60000193 sp : de05dd60 ip : 00000001 fp : 00000000 r10: c085e2f0 r9 : de05c000 r8 : c07be0a4 r7 : de05c000 r6 : de05c000 r5 : c07c5778 r4 : c0824554 r3 : 00000000 r2 : 00000000 r1 : 00000006 r0 : c0529a58 Flags: nZCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment kernel Control: 10c5387d Table: 80004019 DAC: 00000017 Process swapper/0 (pid: 1, stack limit = 0xde05c248) Stack: (0xde05dd60 to 0xde05e000) dd60: c07b9dbc c00cb2dc 00000001 c08242c0 c08242c0 60000113 c07be0a8 c00b0590 dd80: de05c000 c085e2f0 c08242c0 c08242c0 c1414c28 c00b07cc de05b440 c1414c28 dda0: c08242c0 c00b0af8 c0862bb0 c0862db0 c1414cd8 de05c028 c0824840 de05ddb8 ddc0: 00000000 00000009 00000001 00000024 c07be0a8 c07be0a4 de05c000 c085e2f0 dde0: 00000000 c004a4b0 00000010 de00d2dc 00000054 00000100 00000024 00000000 de00: de05c028 0000000a ffff8ae7 00200040 00000016 de05c000 60000193 de05c000 de20: 00000054 00000000 00000000 00000000 00000000 c004a704 00000000 de05c008 de40: c07ba254 c004aa1c c07c5778 c0014b70 fa200000 00000054 de05de80 c0861244 de60: 00000000 c0008634 de05b440 c051c778 20000113 ffffffff de05deb4 c051d0a4 de80: 00000001 00000001 00000000 de05b440 c082afac de057ac0 de057ac0 de0443c0 dea0: 00000000 00000000 00000000 00000000 c082afbc de05dec8 c009f2a0 c051c778 dec0: 20000113 ffffffff 00000000 c016edb0 00000000 000002b0 de057ac0 de057ac0 dee0: 00000000 c016ee40 c0875e50 de05df2e de057ac0 00000000 00000013 00000000 df00: 00000000 c016f054 de043600 de0443c0 c008eb38 de004ec0 c0875e50 c008eb44 df20: 00000012 00000000 00000000 3931f0f8 00000000 00000000 00000014 c0822e84 df40: 00000000 c008ed2c 00000000 00000000 00000000 c07b7490 c07b7490 c075ab3c df60: 00000000 c00701ac 00000002 00000000 c0070160 dffadb73 7bf8edb4 00000000 df80: c051092c 00000000 00000000 00000000 00000000 00000000 00000000 c0510934 dfa0: de05aa40 00000000 c051092c c0013ce8 00000000 00000000 00000000 00000000 dfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 dfe0: 00000000 00000000 00000000 00000000 00000013 00000000 07efffe5 4dfac6f5 [<c0019590>] (arch_irq_work_raise+0x3c/0x48) from [<c00cb2dc>] (irq_work_queue+0xe4/0xf8) [<c00cb2dc>] (irq_work_queue+0xe4/0xf8) from [<c00b0590>] (rcu_accelerate_cbs+0x1d4/0x1d8) [<c00b0590>] (rcu_accelerate_cbs+0x1d4/0x1d8) from [<c00b07cc>] (rcu_start_gp+0x34/0x48) [<c00b07cc>] (rcu_start_gp+0x34/0x48) from [<c00b0af8>] (rcu_process_callbacks+0x318/0x608) [<c00b0af8>] (rcu_process_callbacks+0x318/0x608) from [<c004a4b0>] (__do_softirq+0x114/0x2a0) [<c004a4b0>] (__do_softirq+0x114/0x2a0) from [<c004a704>] (do_softirq+0x6c/0x74) [<c004a704>] (do_softirq+0x6c/0x74) from [<c004aa1c>] (irq_exit+0xac/0x100) [<c004aa1c>] (irq_exit+0xac/0x100) from [<c0014b70>] (handle_IRQ+0x54/0xb4) [<c0014b70>] (handle_IRQ+0x54/0xb4) from [<c0008634>] (omap3_intc_handle_irq+0x60/0x74) [<c0008634>] (omap3_intc_handle_irq+0x60/0x74) from [<c051d0a4>] (__irq_svc+0x44/0x5c) Exception stack(0xde05de80 to 0xde05dec8) de80: 00000001 00000001 00000000 de05b440 c082afac de057ac0 de057ac0 de0443c0 dea0: 00000000 00000000 00000000 00000000 c082afbc de05dec8 c009f2a0 c051c778 dec0: 20000113 ffffffff [<c051d0a4>] (__irq_svc+0x44/0x5c) from [<c051c778>] (_raw_spin_unlock_irq+0x28/0x2c) [<c051c778>] (_raw_spin_unlock_irq+0x28/0x2c) from [<c016edb0>] (proc_alloc_inum+0x30/0xa8) [<c016edb0>] (proc_alloc_inum+0x30/0xa8) from [<c016ee40>] (proc_register+0x18/0x130) [<c016ee40>] (proc_register+0x18/0x130) from [<c016f054>] (proc_mkdir_data+0x44/0x6c) [<c016f054>] (proc_mkdir_data+0x44/0x6c) from [<c008eb44>] (register_irq_proc+0x6c/0x128) [<c008eb44>] (register_irq_proc+0x6c/0x128) from [<c008ed2c>] (init_irq_proc+0x74/0xb0) [<c008ed2c>] (init_irq_proc+0x74/0xb0) from [<c075ab3c>] (kernel_init_freeable+0x84/0x1c8) [<c075ab3c>] (kernel_init_freeable+0x84/0x1c8) from [<c0510934>] (kernel_init+0x8/0x150) [<c0510934>] (kernel_init+0x8/0x150) from [<c0013ce8>] (ret_from_fork+0x14/0x2c) Code: bad PC value Fixes: bf18525fd79 "ARM: 7872/1: Support arch_irq_work_raise() via self IPIs" Reported-by: Olof Johansson <olof@lixom.net> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Tested-by: Olof Johansson <olof@lixom.net> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-11-07ARM: 7872/1: Support arch_irq_work_raise() via self IPIsStephen Boyd
By default, IRQ work is run from the tick interrupt (see irq_work_run() in update_process_times()). When we're in full NOHZ mode, restarting the tick requires the use of IRQ work and if the only place we run IRQ work is in the tick interrupt we have an unbreakable cycle. Implement arch_irq_work_raise() via self IPIs to break this cycle and get the tick started again. Note that we implement this via IPIs which are only available on SMP builds. This shouldn't be a problem because full NOHZ is only supported on SMP builds anyway. Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Reviewed-by: Kevin Hilman <khilman@linaro.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-10-18Merge branch 'for-rmk/arm-mm-lpae' of ↵Russell King
git://git.kernel.org/pub/scm/linux/kernel/git/ssantosh/linux-keystone into devel-stable This series extends the existing ARM v2p runtime patching for 64 bit. Needed for LPAE machines which have physical memory beyond 4GB.
2013-10-10ARM: mm: Introduce virt_to_idmap() with an arch hookSantosh Shilimkar
On some PAE systems (e.g. TI Keystone), memory is above the 32-bit addressable limit, and the interconnect provides an aliased view of parts of physical memory in the 32-bit addressable space. This alias is strictly for boot time usage, and is not otherwise usable because of coherency limitations. On such systems, the idmap mechanism needs to take this aliased mapping into account. This patch introduces virt_to_idmap() and a arch function pointer which can be populated by platform which needs it. Also populate necessary idmap spots with now available virt_to_idmap(). Avoided #ifdef approach to be compatible with multi-platform builds. Most architecture won't touch it and in that case virt_to_idmap() fall-back to existing virt_to_phys() macro. Cc: Russell King <linux@arm.linux.org.uk> Acked-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
2013-09-23ARM: SMP: basic IPI triggered completion supportNicolas Pitre
We need a mechanism to let an inbound CPU signal that it is alive before even getting into the kernel environment i.e. from early assembly code. Using an IPI is the simplest way to achieve that. This adds some basic infrastructure to register a struct completion pointer to be "completed" when the dedicated IPI for this task is received. Signed-off-by: Nicolas Pitre <nico@linaro.org>
2013-09-06Merge tag 'cleanup-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc Pull ARM SoC cleanups from Olof Johansson: "This branch contains code cleanups, moves and removals for 3.12. There's a large number of various cleanups, and a nice net removal of 13500 lines of code. Highlights worth mentioning are: - A series of patches from Stephen Boyd removing the ARM local timer API. - Move of Qualcomm MSM IOMMU code to drivers/iommu. - Samsung PWM driver cleanups from Tomasz Figa, removing legacy PWM driver and switching over to the drivers/pwm one. - Removal of some unusued auto-generated headers for OMAP2+ (PRM/CM). There's also a move of a header file out of include/linux/i2c/ to platform_data, where it really belongs. It touches mostly ARM platform code for include changes so we took it through our tree" * tag 'cleanup-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (83 commits) ARM: OMAP2+: Add back the define for AM33XX_RST_GLOBAL_WARM_SW_MASK gpio: (gpio-pca953x) move header to linux/platform_data/ arm: zynq: hotplug: Remove unreachable code ARM: SAMSUNG: Remove unnecessary exynos4_default_sdhci*() tegra: simplify use of devm_ioremap_resource ARM: SAMSUNG: Remove plat/regs-timer.h header ARM: SAMSUNG: Remove remaining uses of plat/regs-timer.h header ARM: SAMSUNG: Remove pwm-clock infrastructure ARM: SAMSUNG: Remove old PWM timer platform devices pwm: Remove superseded pwm-samsung-legacy driver ARM: SAMSUNG: Modify board files to use new PWM platform device ARM: SAMSUNG: Rework private data handling in dev-backlight pwm: Add new pwm-samsung driver ARM: mach-mvebu: remove redundant DT parsing and validation ARM: msm: Only compile io.c on platforms that use it iommu/msm: Move mach includes to iommu directory ARM: msm: Remove devices-iommu.c ARM: msm: Move mach/board.h contents to common.h ARM: msm: Migrate msm_timer to CLOCKSOURCE_OF_DECLARE ARM: msm: Remove TMR and TMR0 static mappings ...
2013-09-05Merge branches 'debug-choice', 'devel-stable' and 'misc' into for-linusRussell King
2013-09-02ARM: 7830/1: delay: don't bother reporting bogomips in /proc/cpuinfoWill Deacon
Now that we support a timer-backed delay loop, I'm quickly getting sick and tired of people complaining that their beloved bogomips value has decreased. You know who you are! This patch removes the bogomips line from /proc/cpuinfo, based on the reasoning that any program parsing this is already broken and, as such, won't be further broken if the field is removed. Acked-by: Nicolas Pitre <nico@linaro.org> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-08-13ARM: 7807/1: kexec: validate CPU hotplug supportStephen Warren
Architectures should fully validate whether kexec is possible as part of machine_kexec_prepare(), so that user-space's kexec_load() operation can report any problems. Performing validation in machine_kexec() itself is too late, since it is not allowed to return. Prior to this patch, ARM's machine_kexec() was testing after-the-fact whether machine_kexec_prepare() was able to disable all but one CPU. Instead, modify machine_kexec_prepare() to validate all conditions necessary for machine_kexec_prepare()'s to succeed. BUG if the validation succeeded, yet disabling the CPUs didn't actually work. Signed-off-by: Stephen Warren <swarren@nvidia.com> Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>