On Sunday, 14 of September 2008, Jeff Garzik wrote: > Tejun Heo wrote: > > Rafael J. Wysocki wrote: > >> SATA: Blacklist systems that spin off disks during ACPI power off > >> > >> Some notebooks from HP have the problem that their BIOSes attempt to > >> spin down hard drives before entering ACPI system states S4 and S5. > >> This leads to a yo-yo effect during system power-off shutdown and the > >> last phase of hibernation when the disk is first spun down by the > >> kernel and then almost immediately turned on and off by the BIOS. > >> This, in turn, may result in shortening the disk's life times. > >> > >> To prevent this from happening we can blacklist the affected systems > >> using DMI information. However, only the on-board controlles should > >> be blacklisted and their PCI slot numbers can be used for this > >> purpose. Unfortunately the existing interface for checking DMI > >> information of the system is not very convenient for this purpose, > >> because to use it, we would have to define special callback functions > >> or create a separate struct dmi_system_id table for each blacklisted > >> system. > >> > >> To overcome this difficulty introduce a new function > >> dmi_first_match() returning a pointer to the first entry in an array > >> of struct dmi_system_id elements that matches the system DMI > >> information. Then, we can use this pointer to access the entry's > >> .driver_data field containing the additional information, such as > >> the PCI slot number, allowing us to do the desired blacklisting. > >> > >> Introduce a new libata flag ATA_FLAG_NO_POWEROFF_SPINDOWN that, if > >> set, will prevent disks from being spun off during system power off > >> and hibernation (to handle the hibernation case we need a new system > >> state SYSTEM_HIBERNATE_ENTER that can be checked against by libata, > >> in analogy with SYSTEM_POWER_OFF). Use dmi_first_match() to set this > >> flag for some systems affected by the problem described above (HP nx6325, > >> HP nx6310, HP 2510p). > >> > >> Signed-off-by: Rafael J. Wysocki <rjw@xxxxxxx> > > > > libata part looks good to me but I think it would be better to > > separate out DMI changes into a separate patch. > > Did these changes ever get separated out? I only have the 'combo' patch if that's what you're asking about. [The latest version is at http://bugzilla.kernel.org/attachment.cgi?id=17702&action=view] Still, I can easily split the patch, although in that case the reason for the DMI changes won't be very clear without a reference to the SATA changes IMO. Thanks, Rafael -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
