On Thu, Mar 11, 2010 at 10:32:50AM +0200, Avi Kivity wrote: > On 03/02/2010 02:14 AM, Marcelo Tosatti wrote: > >On Mon, Mar 01, 2010 at 07:10:30PM +0100, Jan Kiszka wrote: > >>This grand cleanup drops all reset and vmsave/load related > >>synchronization points in favor of four(!) generic hooks: > >> > >>- cpu_synchronize_all_states in qemu_savevm_state_complete > >> (initial sync from kernel before vmsave) > >>- cpu_synchronize_all_post_init in qemu_loadvm_state > >> (writeback after vmload) > >>- cpu_synchronize_all_post_init in main after machine init > >>- cpu_synchronize_all_post_reset in qemu_system_reset > >> (writeback after system reset) > >> > >>These writeback points + the existing one of VCPU exec after > >>cpu_synchronize_state map on three levels of writeback: > >> > >>- KVM_PUT_RUNTIME_STATE (during runtime, other VCPUs continue to run) > >>- KVM_PUT_RESET_STATE (on synchronous system reset, all VCPUs stopped) > >>- KVM_PUT_FULL_STATE (on init or vmload, all VCPUs stopped as well) > >> > >>This level is passed to the arch-specific VCPU state writing function > >>that will decide which concrete substates need to be written. That way, > >>no writer of load, save or reset functions that interact with in-kernel > >>KVM states will ever have to worry about synchronization again. That > >>also means that a lot of reasons for races, segfaults and deadlocks are > >>eliminated. > >> > >>cpu_synchronize_state remains untouched, just as Anthony suggested. We > >>continue to need it before reading or writing of VCPU states that are > >>also tracked by in-kernel KVM subsystems. > >> > >>Consequently, this patch removes many cpu_synchronize_state calls that > >>are now redundant, just like remaining explicit register syncs. > >> > >>Signed-off-by: Jan Kiszka<jan.kiszka@xxxxxxxxxxx> > >Jan, > > > >This patch breaks system reset of WinXP.32 install (more easily > >reproducible without iothread enabled). > > > > What's the conclusion here? The patch is innocent of the regression? Yes, it is. The problem was caused by a recent seabios change, now fixed. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
