On Mon, 29 Apr 2013, Dave Jones wrote: > When set to built-in, the dummy irq driver causes this trace when I boot.. > > [ 3.996055] genirq: Flags mismatch irq 0. 00000080 (dummy_irq) vs. > 00015a20 (timer) > [ 3.997055] Pid: 1, comm: swapper/0 Not tainted 3.9.0+ #29 > [ 3.997768] Call Trace: > [ 3.998127] [<ffffffff810f8635>] __setup_irq+0x515/0x550 > [ 3.998827] [<ffffffff81f00e8c>] ? loop_init+0x150/0x150 > [ 3.999530] [<ffffffff8146adf0>] ? transfer_xor+0x160/0x160 > [ 4.000259] [<ffffffff810f8809>] request_threaded_irq+0xf9/0x1a0 > [ 4.001041] [<ffffffff81f00e8c>] ? loop_init+0x150/0x150 > [ 4.001740] [<ffffffff81f00eb8>] dummy_irq_init+0x2c/0x60 > [ 4.002450] [<ffffffff810002e2>] do_one_initcall+0x122/0x170 > [ 4.003191] [<ffffffff81ecef5c>] kernel_init_freeable+0x15b/0x1db > [ 4.003978] [<ffffffff81ece7da>] ? do_early_param+0x88/0x88 > [ 4.004710] [<ffffffff816a87e0>] ? rest_init+0x140/0x140 > [ 4.005413] [<ffffffff816a87ee>] kernel_init+0xe/0x180 > [ 4.006094] [<ffffffff816ce91c>] ret_from_fork+0x7c/0xb0 > [ 4.006789] [<ffffffff816a87e0>] ? rest_init+0x140/0x140 > [ 4.007561] dummy-irq: cannot register IRQ 0
Thanks for the report, Dave. That's actually kind of expected -- when one of the handlers on the IRQ line that is being debugged doesn't share IRQs, this is exactly what you want to get by the dummy-irq debugging facility. In this case you haven't specified any IRQ# to the dummy-irq driver via kernel commandline, i.e. IRQ# is 0, and timer is not sharing IRQs, therefore dummy-irq debugging facility did its job, and you know that the IRQ can't be shared. Not really sure whether this is something to fix. We could make dummy-irq a module-only thing, but that might be counter-productive in cases you really want to debug very early problems. Or have it depend on CONFIG_EXPERT would probably make most sense ... ? Thanks, -- Jiri Kosina SUSE Labs -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
