Messages in this thread | | | Date | Thu, 16 Aug 2012 11:13:33 -0400 (EDT) | From | Alan Stern <> | Subject | Re: [REGRESION] Suspend hangs with 3.6-rc1 on Lenovo T60 notebook |
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On Thu, 16 Aug 2012, Hans de Goede wrote:
> Ah right, these are bus_driver operations. That explains some things, so I've > done some more research asking myself: "Why does generic_ide_suspend(), which > is a *bus* op, call dev_get_drvdata?", the answer to that seems to be that > the ide subsystem is abusing (IMHO) drvdata to store per device bus_driver > data. Which I believe is not how drvdata is intended to be used. > > With that said, the above knowledge has allowed me to write an (ugly) fix for > the regression Miklos is seeing. Miklos can you give the attached patch a > try please? > > > It clearly should check if drive is not NULL before using that pointer. > > I assume you mean drive*r*, yes I agree that generic_ide_remove should > check for that. So who is going to write a patch for that?
The existing code could certainly be improved. Your patch does:
> + /* > + * device_register() will have cleared drvdata on > + * device_attach failure, but we use drvdata to store per > + * device bus info, rather then for driver info, so restore it. > + */ > + dev_set_drvdata(dev, drive);
But at this point, dev is defined by:
struct device *dev = &drive->gendev;
So why bother setting anything? It seems to me that generic_ide_suspend() and generic_ide_resume() could easily replace
ide_drive_t *drive = dev_get_drvdata(dev);
with
ide_drive_t *drive = dev_to_ide_drive(dev);
where dev_to_ide_drive is defined as "container_of(dev, ide_drive_t, gendev)" (if this isn't defined already).
Alan Stern
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