When irq_matrix_assign()/irq_matrix_free() calls get unsynced, weird effects are possible, e.g. when cm->allocated goes negative CPU hotplug may get blocked. Add WARN_ON_ONCE() to simplify detecting such situations.
Signed-off-by: Vitaly Kuznetsov <[email protected]> --- kernel/irq/matrix.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/kernel/irq/matrix.c b/kernel/irq/matrix.c index 651a4ad6d711..2438a4f9d726 100644 --- a/kernel/irq/matrix.c +++ b/kernel/irq/matrix.c @@ -189,7 +189,9 @@ void irq_matrix_assign_system(struct irq_matrix *m, unsigned int bit, set_bit(bit, m->system_map); if (replace) { BUG_ON(!test_and_clear_bit(bit, cm->alloc_map)); + WARN_ON_ONCE(!cm->allocated); cm->allocated--; + WARN_ON_ONCE(!m->total_allocated); m->total_allocated--; } if (bit >= m->alloc_start && bit < m->alloc_end) @@ -424,12 +426,17 @@ void irq_matrix_free(struct irq_matrix *m, unsigned int cpu, return; clear_bit(bit, cm->alloc_map); + WARN_ON_ONCE(!cm->allocated); cm->allocated--; - if(managed) + if (managed) { + WARN_ON_ONCE(!cm->managed_allocated); cm->managed_allocated--; + } - if (cm->online) + if (cm->online) { + WARN_ON_ONCE(!m->total_allocated); m->total_allocated--; + } if (!managed) { cm->available++; -- 2.29.2
