kexec: Avoid migration of already disabled irqs (ia64) This patch fixes up ia64 kexec support for HP rx2620 hardware. It does this by skipping migration of already disabled irqs. This is most likely a problem on other ia64 platforms as well, but I've only been able to reproduce it on one machine so far.
The full story is that handle_bad_irq() gets invoked before starting the new kernel without this patch. This seems to happen when fixup_irqs() calls generic_handle_irq() on already migrated (and disabled) irqs. So by avoiding migration of disabled irqs we stay away of handle_bad_irq(). The code has been tested on three different ia64 machines, all with good results. It is possible to trigger the same bug by offlining a processor using echo 0 > /sys/devices/system/cpu/cpuX/online. More detailed information is available in the following mail thread: http://lists.osdl.org/pipermail/fastboot/2007-January/thread.html#5774 Signed-off-by: Magnus Damm <[EMAIL PROTECTED]> Acked-by: Simon Horman <[EMAIL PROTECTED]> Acked-by: Zou, Nanhai <[EMAIL PROTECTED]> Acked-by: Jay Lan <[EMAIL PROTECTED]> --- Tested using kexec-tools-testing 7792798a79b78a5d566f70c9f00237d050b01350 on HP rx2620 hardware. Applies on top of 2.6.20-rc7. arch/ia64/kernel/irq.c | 3 +++ 1 file changed, 3 insertions(+) --- 0001/arch/ia64/kernel/irq.c +++ 0004/arch/ia64/kernel/irq.c 2007-01-30 12:35:10.000000000 +0900 @@ -122,6 +122,9 @@ static void migrate_irqs(void) for (irq=0; irq < NR_IRQS; irq++) { desc = irq_desc + irq; + if (desc->status == IRQ_DISABLED) + continue; + /* * No handling for now. * TBD: Implement a disable function so we can now - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
