xo-1.75: "Trying to free already-free IRQ 40"

[pgf]

got the following backtrace on an A3 1.75, running kernel 2.6.39-33777-g421d1e5:

[  663.688445] atkbd serio2: keyboard reset failed on olpc_keyboard/serio0
[  665.698450] ------------[ cut here ]------------
[  665.698461] WARNING: at kernel/irq/manage.c:1131 __free_irq+0x98/0x190()
[  665.706620] Trying to free already-free IRQ 40
[  665.724871] Modules linked in:
[  665.731547] [<c003178c>] (unwind_backtrace+0x0/0x120) from [<c0041118>] (warn_slowpath_common+0x4c/0x64)
[  665.731547] [<c0041118>] (warn_slowpath_common+0x4c/0x64) from [<c00411b0>] (warn_slowpath_fmt+0x2c/0x3c)
[  665.744739] [<c00411b0>] (warn_slowpath_fmt+0x2c/0x3c) from [<c0080064>] (__free_irq+0x98/0x190)
[  665.770623] [<c0080064>] (__free_irq+0x98/0x190) from [<c0080194>] (free_irq+0x38/0x58)
[  665.770623] [<c0080194>] (free_irq+0x38/0x58) from [<c027dac8>] (serio_close+0x18/0x28)
[  665.782436] [<c027dac8>] (serio_close+0x18/0x28) from [<c0287ee4>] (atkbd_connect+0x204/0x240)
[  665.806761] [<c0287ee4>] (atkbd_connect+0x204/0x240) from [<c027da00>] (serio_connect_driver+0x28/0x3c)
[  665.806761] [<c027da00>] (serio_connect_driver+0x28/0x3c) from [<c01f9ca8>] (driver_probe_device+0x144/0x264)
[  665.833920] [<c01f9ca8>] (driver_probe_device+0x144/0x264) from [<c01f9e28>] (__driver_attach+0x60/0x84)
[  665.847319] [<c01f9e28>] (__driver_attach+0x60/0x84) from [<c01f9358>] (bus_for_each_dev+0x48/0x74)
[  665.847319] [<c01f9358>] (bus_for_each_dev+0x48/0x74) from [<c027e168>] (serio_handle_event+0x138/0x1e8)
[  665.860324] [<c027e168>] (serio_handle_event+0x138/0x1e8) from [<c0054234>] (process_one_work+0x208/0x340)
[  665.873799] [<c0054234>] (process_one_work+0x208/0x340) from [<c005672c>] (worker_thread+0x1dc/0x2f4)
[  665.887486] [<c005672c>] (worker_thread+0x1dc/0x2f4) from [<c0059c98>] (kthread+0x80/0x88)
[  665.913143] [<c0059c98>] (kthread+0x80/0x88) from [<c002cf94>] (kernel_thread_exit+0x0/0x8)
[  665.913143] ---[ end trace d01635eaab59f1eb ]---
[  665.935682] EXT3-fs (mmcblk0p2): error: couldn't mount because of unsupported optional features (240)

a "normal" boot looks like:

[    2.754686] atkbd serio2: keyboard reset failed on olpc_keyboard/serio0
[    5.068470] input: PS/2 Synaptics TouchPad as /devices/platform/olpc-ec-1.75.0/serio1/input/input8

i don't know whether the "keyboard reset failed" message indicates a problem, nor whether it's related to the dup free of the irq.

note that the PS2 Synaptics Touchpad message is missing in the failure case. i don't recall whether the touchpad was functional on that boot.