/* * Preemptible hypercalls * * Copyright (C) 2014 Citrix Systems R&D ltd. * * This source code is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License as * published by the Free Software Foundation; either version 2 of the * License, or (at your option) any later version. */ #include #include #ifndef CONFIG_PREEMPT /* * Some hypercalls issued by the toolstack can take many 10s of * seconds. Allow tasks running hypercalls via the privcmd driver to * be voluntarily preempted even if full kernel preemption is * disabled. * * Such preemptible hypercalls are bracketed by * xen_preemptible_hcall_begin() and xen_preemptible_hcall_end() * calls. */ DEFINE_PER_CPU(bool, xen_in_preemptible_hcall); EXPORT_SYMBOL_GPL(xen_in_preemptible_hcall); asmlinkage __visible void xen_maybe_preempt_hcall(void) { if (unlikely(__this_cpu_read(xen_in_preemptible_hcall) && need_resched())) { /* * Clear flag as we may be rescheduled on a different * cpu. */ __this_cpu_write(xen_in_preemptible_hcall, false); _cond_resched(); __this_cpu_write(xen_in_preemptible_hcall, true); } } #endif /* CONFIG_PREEMPT */ e net-next plumbingsTobias Klauser
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authorBenjamin Herrenschmidt <benh@kernel.crashing.org>2017-02-03 17:10:28 +1100
committerMichael Ellerman <mpe@ellerman.id.au>2017-02-08 23:36:29 +1100
commitd7df2443cd5f67fc6ee7c05a88e4996e8177f91b (patch)
tree098a7c0ca4fceb8a65cb1f693c9d71990388933d /include/sound/ad1816a.h
parenta0615a16f7d0ceb5804d295203c302d496d8ee91 (diff)
powerpc/mm: Fix spurrious segfaults on radix with autonuma
When autonuma (Automatic NUMA balancing) marks a PTE inaccessible it clears all the protection bits but leave the PTE valid. With the Radix MMU, an attempt at executing from such a PTE will take a fault with bit 35 of SRR1 set "SRR1_ISI_N_OR_G". It is thus incorrect to treat all such faults as errors. We should pass them to handle_mm_fault() for autonuma to deal with. The case of pages that are really not executable is handled by the existing test for VM_EXEC further down. That leaves us with catching the kernel attempts at executing user pages. We can catch that earlier, even before we do find_vma. It is never valid on powerpc for the kernel to take an exec fault to begin with. So fold that test with the existing test for the kernel faulting on kernel addresses to bail out early. Fixes: 1d18ad026844 ("powerpc/mm: Detect instruction fetch denied and report") Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Acked-by: Balbir Singh <bsingharora@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'include/sound/ad1816a.h')