On 03/25/2016 12:45 PM, Greg Kurz wrote: > Hi Cedric, > > On Thu, 24 Mar 2016 16:28:53 +0100 > Cédric Le Goater <c...@fr.ibm.com> wrote: > >> This address is changed by the linux kernel using the H_SET_MODE hcall >> and needs to be migrated in order to restart a spapr VM running in >> TCG. This can be done using the AIL bits from the LPCR register. >> >> The patch introduces a spapr_h_set_mode_resource_addr() helper to >> share some code with the H_SET_MODE hcall. >> >> Signed-off-by: Cédric Le Goater <c...@fr.ibm.com> >> --- >> hw/ppc/spapr.c | 21 +++++++++++++++++++++ >> hw/ppc/spapr_hcall.c | 13 ++----------- >> include/hw/ppc/spapr.h | 14 ++++++++++++++ >> 3 files changed, 37 insertions(+), 11 deletions(-) >> >> Index: qemu-dgibson-for-2.6.git/hw/ppc/spapr.c >> =================================================================== >> --- qemu-dgibson-for-2.6.git.orig/hw/ppc/spapr.c >> +++ qemu-dgibson-for-2.6.git/hw/ppc/spapr.c >> @@ -1244,6 +1244,24 @@ static bool spapr_vga_init(PCIBus *pci_b >> } >> } >> >> +static int load_excp_prefix(void) >> +{ >> + CPUState *cs; >> + >> + CPU_FOREACH(cs) { >> + CPUPPCState *env = &POWERPC_CPU(cs)->env; > > And how are we sure env contains the migrated register values ? > > Actually, this "works" because vmstate_ppc_cpu is registered before > vmstate_spapr, > and the same ordering happens to be used when sending state over the wire, > but it > looks wrong. > > The excp_prefix should be restored in cpu_post_load(), unless I'm missing > something.
ah yes. You're right. It was there initially but as this is specific spar, I moved the code out. Bad choice. Thanks, C. > Cheers. > > -- > Greg > >> + int ail = (env->spr[SPR_LPCR] & LPCR_AIL) >> LPCR_AIL_SHIFT; >> + >> + env->excp_prefix = spapr_h_set_mode_resource_addr(ail); >> + if (env->excp_prefix == H_UNSUPPORTED_FLAG) { >> + error_report("LPCR has an invalid AIL value"); >> + return -EINVAL; >> + } >> + } >> + >> + return 0; >> +} >> + >> static int spapr_post_load(void *opaque, int version_id) >> { >> sPAPRMachineState *spapr = (sPAPRMachineState *)opaque; >> @@ -1257,6 +1275,9 @@ static int spapr_post_load(void *opaque, >> err = spapr_rtc_import_offset(spapr->rtc, spapr->rtc_offset); >> } >> >> + if (!err) { >> + err = load_excp_prefix(); >> + } >> return err; >> } >> >> Index: qemu-dgibson-for-2.6.git/include/hw/ppc/spapr.h >> =================================================================== >> --- qemu-dgibson-for-2.6.git.orig/include/hw/ppc/spapr.h >> +++ qemu-dgibson-for-2.6.git/include/hw/ppc/spapr.h >> @@ -561,6 +561,20 @@ struct sPAPREventLogEntry { >> QTAILQ_ENTRY(sPAPREventLogEntry) next; >> }; >> >> +static inline target_ulong spapr_h_set_mode_resource_addr(target_ulong >> mflags) >> +{ >> + switch (mflags) { >> + case H_SET_MODE_ADDR_TRANS_NONE: >> + return 0; >> + case H_SET_MODE_ADDR_TRANS_0001_8000: >> + return 0x18000; >> + case H_SET_MODE_ADDR_TRANS_C000_0000_0000_4000: >> + return 0xC000000000004000ULL; >> + default: >> + return H_UNSUPPORTED_FLAG; >> + } >> +} >> + >> void spapr_events_init(sPAPRMachineState *sm); >> void spapr_events_fdt_skel(void *fdt, uint32_t epow_irq); >> int spapr_h_cas_compose_response(sPAPRMachineState *sm, >> Index: qemu-dgibson-for-2.6.git/hw/ppc/spapr_hcall.c >> =================================================================== >> --- qemu-dgibson-for-2.6.git.orig/hw/ppc/spapr_hcall.c >> +++ qemu-dgibson-for-2.6.git/hw/ppc/spapr_hcall.c >> @@ -835,17 +835,8 @@ static target_ulong h_set_mode_resource_ >> return H_P4; >> } >> >> - switch (mflags) { >> - case H_SET_MODE_ADDR_TRANS_NONE: >> - prefix = 0; >> - break; >> - case H_SET_MODE_ADDR_TRANS_0001_8000: >> - prefix = 0x18000; >> - break; >> - case H_SET_MODE_ADDR_TRANS_C000_0000_0000_4000: >> - prefix = 0xC000000000004000ULL; >> - break; >> - default: >> + prefix = spapr_h_set_mode_resource_addr(mflags); >> + if (prefix == H_UNSUPPORTED_FLAG) { >> return H_UNSUPPORTED_FLAG; >> } >> >> >> >