Commit a1967d64 authored Nov 21, 2008 by Thomas Gleixner Committed by Ingo Molnar Nov 23, 2008

x86: revert irq number limitation

Impact: fix MSIx not enough irq numbers available regression

The manual revert of the sparse_irq patches missed to bring the number
of possible irqs back to the .27 status. This resulted in a regression
when two multichannel network cards were placed in a system with only
one IO_APIC - causing the networking driver to not have the right
IRQ and the device not coming up.

Remove the dynamic allocation logic leftovers and simply return
NR_IRQS in probe_nr_irqs() for now.

   Fixes: http://lkml.org/lkml/2008/11/19/354



Reported-by: Jesper Dangaard Brouer <hawk@diku.dk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Jesper Dangaard Brouer <hawk@diku.dk>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

parent 57550b27

arch/x86/kernel/io_apic.c

+1 −21

Original line number	Diff line number	Diff line
		@@ -3608,27 +3608,7 @@ int __init io_apic_get_redir_entries (int ioapic)

		int __init probe_nr_irqs(void)
		{
		int idx;
		int nr = 0;
		#ifndef CONFIG_XEN
		int nr_min = 32;
		#else
		int nr_min = NR_IRQS;
		#endif

		for (idx = 0; idx < nr_ioapics; idx++)
		nr += io_apic_get_redir_entries(idx) + 1;

		/* double it for hotplug and msi and nmi */
		nr <<= 1;

		/* something wrong ? */
		if (nr < nr_min)
		nr = nr_min;
		if (WARN_ON(nr > NR_IRQS))
		nr = NR_IRQS;

		return nr;
		return NR_IRQS;
		}

		/* --------------------------------------------------------------------------

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