Messages in this thread |  | | Date | Fri, 22 Jun 2001 08:23:08 -0700 | From | Jonathan Lundell <> | Subject | Re: Q serial.c |
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At 9:51 AM -0400 2001-06-22, Stuart MacDonald wrote: >From: "kees" <kees@schoen.nl> >> What may happen on a SMP machine if a serial port has been closed and the >> closing stage is at shutdown() in serial.c in the call to free_IRQ and >> BEFORE the IRQ is really shutdown, a new character arrives which causes an >> IRQ? Is it possible that the OTHER cpu takes this interrupt and causes a >> crash? > >I'm looking at serial-5.05/serial.c. You'll notice at the >beginning of shutdown the saveflags(); cli(); calls. >This disables interrupts. The uart will not be able to >generate IRQs even if new characters arrive.
The other CPU servicing the interrupt, was the question. cli() doesn't affect that. This could presumably happen if shutdown() gets run on a non-interrupt-servicing CPU, or if interrupts are dynamically routed (eg round-robin).
Where can I find the 5.05 driver? -- /Jonathan Lundell. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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