On Thu, 9 Jul 2020 14:21:04 +0200 Philippe Mathieu-Daudé <phi...@redhat.com> wrote:
> On 7/9/20 12:55 PM, Greg Kurz wrote: > > On Thu, 9 Jul 2020 12:18:06 +0200 > > Philippe Mathieu-Daudé <phi...@redhat.com> wrote: > > [...] > >>> > >>> FYI, PAPR requires all vCPUs to be "stopped" by default. It is up to the > >>> guest to start them explicitly through an RTAS call. The hypervisor is > >>> only responsible to start a single vCPU (see spapr_cpu_set_entry_state() > >>> called from spapr_machine_reset()) to be able to boot the guest. > >>> > >>> So I'm not sure to see how that would depend on the accelerator... > >> > >> $ qemu-system-ppc64 -M pseries-5.0,accel=tcg -d in_asm > >> qemu-system-ppc64: warning: TCG doesn't support requested feature, > >> cap-cfpc=workaround > >> qemu-system-ppc64: warning: TCG doesn't support requested feature, > >> cap-sbbc=workaround > >> qemu-system-ppc64: warning: TCG doesn't support requested feature, > >> cap-ibs=workaround > >> qemu-system-ppc64: warning: TCG doesn't support requested feature, > >> cap-ccf-assist=on > >> ---------------- > >> IN: > >> 0x00000100: 48003f00 b 0x4000 > >> > >> ---------------- > >> IN: > >> 0x00004000: 7c7f1b78 mr r31, r3 > >> 0x00004004: 7d6000a6 mfmsr r11 > >> 0x00004008: 3980a000 li r12, 0xa000 > >> 0x0000400c: 798c83c6 sldi r12, r12, 0x30 > >> 0x00004010: 7d6b6378 or r11, r11, r12 > >> 0x00004014: 7d600164 mtmsrd r11 > >> ... > >> > >> The vCPU doesn't seem stopped to me... > >> > >> Am I missing something? > >> > > > > Yeah this is the boot vCPU which is required to be started > > by the platform as explained above, but if you had more > > vCPUs the other ones would be stopped until the guest OS > > asks us to start them. > > Ah OK, so we are good :) > > The machine simply has to set the 'start-powered-off' flag on > all vCPUS except the 1st one. > We only want the first vCPU to start when the platform is fully configured, so I'd rather put 'start-powered-off' on every body and explicitly power on the first one during machine reset as we do now.
