From: Beth Kon Date: Tue, 7 Jul 2009 15:50:38 +0000 (-0400) Subject: KVM: PIT support for HPET legacy mode X-Git-Tag: v2.6.32-rc1~693^2~88 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=e9f4275732add046fed4a548b8dbb98dbe500d2f;p=pandora-kernel.git KVM: PIT support for HPET legacy mode When kvm is in hpet_legacy_mode, the hpet is providing the timer interrupt and the pit should not be. So in legacy mode, the pit timer is destroyed, but the *state* of the pit is maintained. So if kvm or the guest tries to modify the state of the pit, this modification is accepted, *except* that the timer isn't actually started. When we exit hpet_legacy_mode, the current state of the pit (which is up to date since we've been accepting modifications) is used to restart the pit timer. The saved_mode code in kvm_pit_load_count temporarily changes mode to 0xff in order to destroy the timer, but then restores the actual value, again maintaining "current" state of the pit for possible later reenablement. [avi: add some reserved storage in the ioctl; make SET_PIT2 IOW] [marcelo: fix memory corruption due to reserved storage] Signed-off-by: Beth Kon Signed-off-by: Marcelo Tosatti Signed-off-by: Avi Kivity --- Reading git-diff-tree failed