On Wednesday 19 August 2009, Alan Stern wrote: > On Wed, 19 Aug 2009, Rafael J. Wysocki wrote: > > > On Monday 17 August 2009, Xiaotian Feng wrote: > > > transition_started should be set once the preparation of devices for > > > a PM has started, reset before starting to resume devices. When resuming > > > devices, kernel calls dpm_resume_noirq then dpm_resume_end(dpm_resume). > > > Thus we should reset transition_started at dpm_resume_noirq. > > > > > > This patch fixes acpi warning when resuming from suspend/hibernate: > > > > > > ACPI: \_SB_.PCI0.IDE1.PRI1.MAS1 - docking > > > ------------[ cut here ]------------ > > > WARNING: at drivers/base/power/main.c:87 device_pm_add+0x8b/0xcc() > > > Hardware name: OptiPlex 760 > > > Device: acpi > > > Parentless device registered during a PM transaction > > > Modules linked in: fuse sco bridge stp llc bnep l2cap bluetooth sunrpc ip6t_REJECT nf_conntrack_ipv6 ip6table_filter ip6_tables ipv6 dm_multipath uinput snd_hda_codec_analog radeon ppdev parport_pc snd_hda_intel ttm snd_hda_codec serio_raw snd_hwdep iTCO_wdt drm i2c_i801 parport iTCO_vendor_support pcspkr snd_pcm snd_timer i2c_algo_bit i2c_core snd dcdbas wmi e1000e soundcore snd_page_alloc ata_generic pata_acpi [last unloaded: speedstep_lib] > > > Pid: 33, comm: kacpi_hotplug Not tainted 2.6.31-rc5 #51 > > > Call Trace: > > > [<ffffffff8104ece1>] warn_slowpath_common+0x7c/0x94 > > > [<ffffffff8104ed50>] warn_slowpath_fmt+0x41/0x43 > > > [<ffffffff812ae827>] device_pm_add+0x8b/0xcc > > > [<ffffffff812a820b>] device_add+0x36f/0x519 > > > [<ffffffff812a83d3>] device_register+0x1e/0x22 > > > [<ffffffff81245c86>] acpi_add_single_object+0xb48/0xd68 > > > [<ffffffff810750d6>] ? trace_hardirqs_on_caller+0x1f/0x159 > > > [<ffffffff8107521d>] ? trace_hardirqs_on+0xd/0xf > > > [<ffffffff812461cb>] acpi_bus_add+0x2a/0x40 > > > [<ffffffff81244128>] ? acpi_bus_get_device+0x47/0x66 > > > [<ffffffff81247c52>] hotplug_dock_devices+0x109/0x133 > > > [<ffffffff812423b1>] ? acpi_os_execute_hp_deferred+0x0/0x43 > > > [<ffffffff81248013>] acpi_dock_deferred_cb+0xbf/0x192 > > > [<ffffffff812423e7>] acpi_os_execute_hp_deferred+0x36/0x43 > > > [<ffffffff8106099a>] worker_thread+0x215/0x31d > > > [<ffffffff81060945>] ? worker_thread+0x1c0/0x31d > > > [<ffffffff81415f34>] ? thread_return+0x3e/0xaf > > > [<ffffffff810739bb>] ? lock_release_holdtime+0x2c/0x11d > > > [<ffffffff8106549e>] ? autoremove_wake_function+0x0/0x39 > > > [<ffffffff81060785>] ? worker_thread+0x0/0x31d > > > [<ffffffff8106513c>] kthread+0x8a/0x92 > > > [<ffffffff81012d4a>] child_rip+0xa/0x20 > > > [<ffffffff810126d0>] ? restore_args+0x0/0x30 > > > [<ffffffff810650b2>] ? kthread+0x0/0x92 > > > [<ffffffff81012d40>] ? child_rip+0x0/0x20 > > > ---[ end trace 6f4892372e7d9f1a ]--- > > > > > > Signed-off-by: Xiaotian Feng <dfeng@xxxxxxxxxx> > > > > OK, we can do this IMO. > > > > Alan, what do you think? > > I suppose so. The difference between dpm_resume() and > dpm_resume_noirq() is minimal. > > But at the same time, I wonder if this isn't really a bug in ACPI. > Why does it want to register a new top-level device during the > resume_noirq phase? > > The stack trace indicates that the registration occurred from within a > workqueue. Maybe it should be moved to a freezable workqueue; that > would prevent it from happening too early. This looks like the box was put into a docking station while suspended or something like this, which would indicate that the action was legitimate. Anyway, I don't think that's anything the core has to care about. :-) Thanks, Rafael _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
