Am 05.09.2012 05:28, schrieb Alexander Graf: > > On 04.09.2012, at 16:08, Jason Baron wrote: > >> While testing q35, I found that windows 7 (specifically, windows 7 ultimate >> with sp1 x64), wouldn't install because it can't find the cdrom or disk >> drive. >> The failure message is: 'A required cd/dvd device driver is missing. If you >> have a driver floppy disk, CD, DVD, or USB flash drive, please insert it >> now.' >> This can also be reproduced on piix by adding an ahci controller, and >> observing that windows 7 does not see any devices behind it. >> >> The problem is that when windows issues a HBA reset, qemu does not reset the >> individual ports' PxCMD register. Windows 7 then reads back the PxCMD >> register >> and presumably assumes that the ahci controller has already been initialized. >> Windows then never sets up the PxIE register to enable interrupts, and thus >> it >> never gets irqs back when it sends ata device inquiry commands. >> >> This change brings qemu into ahci 1.3 specification compliance. >> >> Section 10.4.3 HBA Reset: >> >> " >> When GHC.HR is set to '1', GHC.AE, GHC.IE, the IS register, and all port >> register fields (except PxFB/PxFBU/PxCLB/PxCLBU) that are not HwInit in the >> HBA's register memory space are reset. >> " >> >> I've also re-tested Fedora 16 and 17 to verify that they continue to work >> with >> this change. >> >> Signed-off-by: Jason Baron <jba...@redhat.com> > > Awesome, a lot cleaner now :). > > Acked-by: Alexander Graf <ag...@suse.de>
Thanks, applied to block-next. Kevin
