On Tue, 02 Apr 2013 20:40:53 -0400 Sasha Levin <sasha.levin@xxxxxxxxxx> wrote: > On 02/28/2013 04:22 AM, Cornelia Huck wrote: > > Currently, eventfd introduces module_init/module_exit functions > > to initialize/cleanup the irqfd workqueue. This only works, however, > > if no other module_init/module_exit functions are built into the > > same module. > > > > Let's just move the initialization and cleanup to kvm_init and kvm_exit. > > This way, it is also clearer where kvm startup may fail. > > > > Signed-off-by: Cornelia Huck <cornelia.huck@xxxxxxxxxx> > > I'm seeing this during boot: > > [ 6.763302] ------------[ cut here ]------------ > [ 6.763763] WARNING: at kernel/workqueue.c:4204 destroy_workqueue+0x1df/0x3d0() > [ 6.764507] Modules linked in: > [ 6.764792] Pid: 1, comm: swapper/0 Tainted: G W 3.9.0-rc5-next-20130402-sasha-00015-g3522ec5 #324 > [ 6.765654] Call Trace: > [ 6.765875] [<ffffffff811074fb>] warn_slowpath_common+0x8b/0xc0 > [ 6.766436] [<ffffffff81107545>] warn_slowpath_null+0x15/0x20 > [ 6.766947] [<ffffffff8112ca7f>] destroy_workqueue+0x1df/0x3d0 > [ 6.768631] [<ffffffff8100d880>] kvm_irqfd_exit+0x10/0x20 > [ 6.770000] [<ffffffff81004dbb>] kvm_init+0x2ab/0x310 > [ 6.770607] [<ffffffff86183dc0>] ? cpu_has_kvm_support+0x4d/0x4d > [ 6.771241] [<ffffffff86183fb4>] vmx_init+0x1f4/0x437 > [ 6.771709] [<ffffffff86183dc0>] ? cpu_has_kvm_support+0x4d/0x4d > [ 6.772266] [<ffffffff810020f2>] do_one_initcall+0xb2/0x1b0 > [ 6.772995] [<ffffffff86180021>] kernel_init_freeable+0x15d/0x1ef > [ 6.773857] [<ffffffff8617f801>] ? loglevel+0x31/0x31 > [ 6.774609] [<ffffffff83d51230>] ? rest_init+0x140/0x140 > [ 6.775551] [<ffffffff83d51239>] kernel_init+0x9/0xf0 > [ 6.776162] [<ffffffff83dbf37c>] ret_from_fork+0x7c/0xb0 > [ 6.776662] [<ffffffff83d51230>] ? rest_init+0x140/0x140 > [ 6.777241] ---[ end trace 10bba684ced4346a ]--- > > And I think it has something to do with this patch. What this patch does is move initialization of the workqueue - the code called should be indentical. The workqueue created/destroyed should not have been touched (no irqfds yet), but the new workqueue code seems to encounter something unexpected. I'd expect destroy_workqueue() to be callable after a successful create_singlethread_workqueue(). Tejun? > > > Thanks, > Sasha > -- To unsubscribe from this list: send the line "unsubscribe linux-s390" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html