Re: [patch] x86_64, irq: check remote IRR bit before migrating level triggered irq

From: Yinghai Lu
Date: Fri May 18 2007 - 14:28:34 EST


On 5/18/07, Siddha, Suresh B <suresh.b.siddha@xxxxxxxxx> wrote:

If the vector number stays same during irq migration and if we reset remote
IRR bit using the above method(edge and then back to level) during
irq migration, then we have a problem. A new interrupt arriving on a new
cpu will set the remote IRR bit and now the old inflight EOI broadcast
reaches IOAPIC RTE(resetting the remote IRR bit, because the vector in the
broadcast msg is same), while the kernel code still assumes that the remote
IRR bit is still set. This will lead to more problems and issues.

coud add some line __assign_irq_vector. to make sure old_vector!=vector.

YH
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