diff options
| author | Nicholas Piggin <npiggin@gmail.com> | 2023-05-24 16:08:18 +1000 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2023-08-02 22:22:18 +1000 |
| commit | c3c2e93753484bb4e935ed8205c1f569907f5970 (patch) | |
| tree | 55a5f271fb496d435ae6b1c36766c125d9c5e7fb | |
| parent | ab481817912ec5c882a6a42ce12c57aed3cfd506 (diff) | |
powerpc: Account mm_cpumask and active_cpus in init_mm
init_mm mm_cpumask and context.active_cpus is not maintained at boot
and hotplug. This seems to be harmless because init_mm does not have a
userspace and so never gets user TLBs flushed, but it looks odd and it
prevents some sanity checks being added.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230524060821.148015-2-npiggin@gmail.com
| -rw-r--r-- | arch/powerpc/kernel/setup-common.c | 6 | ||||
| -rw-r--r-- | arch/powerpc/kernel/smp.c | 12 | ||||
| -rw-r--r-- | arch/powerpc/mm/mmu_context.c | 1 |
3 files changed, 18 insertions, 1 deletions
diff --git a/arch/powerpc/kernel/setup-common.c b/arch/powerpc/kernel/setup-common.c index d2a446216444..16843294d978 100644 --- a/arch/powerpc/kernel/setup-common.c +++ b/arch/powerpc/kernel/setup-common.c @@ -969,8 +969,12 @@ void __init setup_arch(char **cmdline_p) klp_init_thread_info(&init_task); setup_initial_init_mm(_stext, _etext, _edata, _end); - + /* sched_init() does the mmgrab(&init_mm) for the primary CPU */ + VM_WARN_ON(cpumask_test_cpu(smp_processor_id(), mm_cpumask(&init_mm))); + cpumask_set_cpu(smp_processor_id(), mm_cpumask(&init_mm)); + inc_mm_active_cpus(&init_mm); mm_iommu_init(&init_mm); + irqstack_early_init(); exc_lvl_early_init(); emergency_stack_init(); diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c index fbbb695bae3d..8cb6d1c90266 100644 --- a/arch/powerpc/kernel/smp.c +++ b/arch/powerpc/kernel/smp.c @@ -47,6 +47,7 @@ #include <asm/smp.h> #include <asm/time.h> #include <asm/machdep.h> +#include <asm/mmu_context.h> #include <asm/cputhreads.h> #include <asm/cputable.h> #include <asm/mpic.h> @@ -1616,6 +1617,9 @@ void start_secondary(void *unused) mmgrab_lazy_tlb(&init_mm); current->active_mm = &init_mm; + VM_WARN_ON(cpumask_test_cpu(smp_processor_id(), mm_cpumask(&init_mm))); + cpumask_set_cpu(cpu, mm_cpumask(&init_mm)); + inc_mm_active_cpus(&init_mm); smp_store_cpu_info(cpu); set_dec(tb_ticks_per_jiffy); @@ -1751,6 +1755,14 @@ int __cpu_disable(void) void __cpu_die(unsigned int cpu) { + /* + * This could perhaps be a generic call in idlea_task_dead(), but + * that requires testing from all archs, so first put it here to + */ + VM_WARN_ON_ONCE(!cpumask_test_cpu(cpu, mm_cpumask(&init_mm))); + dec_mm_active_cpus(&init_mm); + cpumask_clear_cpu(cpu, mm_cpumask(&init_mm)); + if (smp_ops->cpu_die) smp_ops->cpu_die(cpu); } diff --git a/arch/powerpc/mm/mmu_context.c b/arch/powerpc/mm/mmu_context.c index 1fb9c99f8679..894468975a44 100644 --- a/arch/powerpc/mm/mmu_context.c +++ b/arch/powerpc/mm/mmu_context.c @@ -47,6 +47,7 @@ void switch_mm_irqs_off(struct mm_struct *prev, struct mm_struct *next, /* Mark this context has been used on the new CPU */ if (!cpumask_test_cpu(smp_processor_id(), mm_cpumask(next))) { + VM_WARN_ON_ONCE(next == &init_mm); cpumask_set_cpu(smp_processor_id(), mm_cpumask(next)); inc_mm_active_cpus(next); |