On Friday, 7 of November 2008, Robert Hancock wrote: > Matthew Garrett wrote: > > On Fri, Nov 07, 2008 at 09:01:19AM +0800, Zhao Yakui wrote: > > > >> With the help of KVM I find that the windows will be rebooted by writing > >> RESET_VALUE to RESET_REG I/O port if the RESET_REG_SUP bit is not > >> zero(It indicates whether ACPI reboot is supported). > >> IMO maybe the ACPI reboot is the first choice. If it can't, then it will > >> fall back to other mode. > > > > Hmm. But we're seeing some machines that end up very confused if > > rebooted via ACPI. I guess we need to run Vista on them to find out how > > they behave. What OSI strings did your KVM setup expose? We know that > > Windows changes behaviour under various circumstances depending on which > > OS the firmware requests, so it's almost possible that this is another > > of those cases. > > Given that Windows behavior, this patch seems suspicious: > > http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=8fd145917fb62368a9b80db59562c20576238f5a > > This patch ignores the RESET_REG_SUP flag and just tries using the reset > register anyway if it thinks it's valid. So we may attempt ACPI reset on > machines which don't indicate it's supported. > > The patch description mentioned that some machines didn't reboot after > S3 suspend without this patch. However, we recently had this patch merged: > > http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=a68823ee5285e65b51ceb96f8b13a5b4f99a6888 > > Is it possible that the problem fixed there is the true cause of this > reboot after S3 problem? Generally, it is. Should it regarded as -stable material, BTW, or is it already in -stable? Matthew? 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
