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This is, afaict, a result of previously used > channels retaining their IRQ affinity until some other CPU re-uses them. > Such nesting is increasingly problematic with higher CPU counts, as both > handle_hpet_broadcast() and cpumask_raise_softirq() have a cpumask_t local > variable. IOW already a single level of nesting may require more stack > space (2 times above 4k) than we have available (8k), when NR_CPUS=16383 > (the maximum value presently possible). > > Signed-off-by: Jan Beulich > --- > Whether this is still worthwhile with "x86/HPET: use single, global, low- > priority vector for broadcast IRQ" isn't quite clear to me. Seeing the rest of the series, I don't think this is necessary anymore? Also the comment you here is made stale by the patch that uses a global vector. Thanks, Roger.