Messages in this thread | | | Date | Fri, 17 Feb 2012 23:52:15 -0800 (PST) | From | Hugh Dickins <> | Subject | Re: linux-next: dock_link_device is oopsy |
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On Sat, 18 Feb 2012, Holger Macht wrote: > On Fr 17. Feb - 14:42:31, Hugh Dickins wrote: > > On Fri, 17 Feb 2012, Holger Macht wrote: > > > On Fr 17. Feb - 13:46:04, Hugh Dickins wrote: > > > > Matthew, > > > > > > > > A linux-next oops at bootup in dock_link_device() tells me that you > > > > were not feeling well when you wrote that and dock_unlink_device(): > > > > I hope you're feeling better now and can rewrite them soon. > > > > > > Andrew Morton experienced a similar problem. What system are you using? > > > I didn't encounter this problem with the systems I tested with. > > > > The two systems I got that on were both 4-year-old Core2 Duo systems, > > one an HP quad desktop, one a Fujitsu-Siemens laptop. > > Thanks for the information I think this is really independent from the > fact if a laptop, or more precicely if a system with dock station/bay is > used. > > > > > > > > > Do you actually have a /sys/devices/platform/dock.?/ directory with a > > > file 'type' that contains 'dock_station'? > > > > I'll have to report back on that this evening, I'm away from them now. > > I actually guess that those systems don't have a > /sys/devices/platform/dock.? directory at all, which is fine.
You are correct, no /sys/devices/platform/dock.? directory on those.
> > I also think this will fix it, would be great if you could confirm this: > > acpi: Bail out when linking devices and there are no dock stations > > If dock_station_count is zero, we allocate zero memory and don't check > this at future references. So bail out if there are actually no dock > stations. > > Signed-off-by: Holger Macht <holger@homac.de> > --- > drivers/acpi/dock.c | 13 ++++++++++--- > 1 files changed, 10 insertions(+), 3 deletions(-) > > diff --git a/drivers/acpi/dock.c b/drivers/acpi/dock.c > index b5e4142..8641912 100644 > --- a/drivers/acpi/dock.c > +++ b/drivers/acpi/dock.c > @@ -286,6 +286,9 @@ struct device **dock_link_device(acpi_handle handle) > int ret, dock = 0; > struct device **devices; > > + if (!dock_station_count) > + return -ENODEV;
If I change your -ENODEV to NULL (here and in unlink, though I didn't check if that gets called), yes, that "fixes" the crash at boot.
But note that in each case you already did an acpi_get_physical_device: if the existing code was correct in this regard, then you ought to be doing a put_device(dev) before returning.
Or better reorder it all.
Hugh
> + > devices = kmalloc(dock_station_count * sizeof(struct device *), > GFP_KERNEL); > > @@ -323,9 +326,13 @@ struct device **dock_unlink_device(acpi_handle handle) > struct device *dev = acpi_get_physical_device(handle); > struct dock_station *dock_station; > int dock = 0; > - struct device **devices = > - kmalloc(dock_station_count * sizeof(struct device *), > - GFP_KERNEL); > + struct device **devices; > + > + if (!dock_station_count) > + return -ENODEV; > + > + devices = kmalloc(dock_station_count * sizeof(struct device *), > + GFP_KERNEL); > > if (!dev) > return NULL; > -- > 1.7.7
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