Re: [PATCH 1/3] sparc64: use memory_region_allocate_system_memory() only for '-m' specified RAM

[Igor Mammedov <imammedo@redhat.com>]

On Tue, 8 Oct 2019 14:09:28 +0200
Philippe Mathieu-Daudé <philmd@redhat.com> wrote:

> On 10/8/19 1:33 PM, Igor Mammedov wrote:
> > memory_region_allocate_system_memory() was designed to be called for
> > allocating inital RAM. Using it mutiple times within one board is not
> > supported and could fail if -mem-path with non hugepage path is used.
> > 
> > Keep using memory_region_allocate_system_memory() only for initial
> > RAM and use memory_region_init_ram() for the rest fixed size regions.
> > 
> > Signed-off-by: Igor Mammedov <imammedo@redhat.com>
> > ---
> >   hw/sparc64/niagara.c | 25 +++++++++++++------------
> >   1 file changed, 13 insertions(+), 12 deletions(-)
> > 
> > diff --git a/hw/sparc64/niagara.c b/hw/sparc64/niagara.c
> > index 167143bffe..5987693659 100644
> > --- a/hw/sparc64/niagara.c
> > +++ b/hw/sparc64/niagara.c
> > @@ -36,6 +36,7 @@
> >   #include "qemu/error-report.h"
> >   #include "sysemu/qtest.h"
> >   #include "sysemu/sysemu.h"
> > +#include "qapi/error.h"
> >   
> >   typedef struct NiagaraBoardState {
> >       MemoryRegion hv_ram;
> > @@ -106,8 +107,8 @@ static void niagara_init(MachineState *machine)
> >       /* init CPUs */
> >       sparc64_cpu_devinit(machine->cpu_type, NIAGARA_PROM_BASE);
> >       /* set up devices */
> > -    memory_region_allocate_system_memory(&s->hv_ram, NULL, "sun4v-hv.ram",
> > -                                         NIAGARA_HV_RAM_SIZE);
> > +    memory_region_init_ram(&s->hv_ram, NULL, "sun4v-hv.ram",
> > +                           NIAGARA_HV_RAM_SIZE, &error_fatal);
> >       memory_region_add_subregion(sysmem, NIAGARA_HV_RAM_BASE, &s->hv_ram);
> >   
> >       memory_region_allocate_system_memory(&s->partition_ram, NULL,  
> 
> Did we have an issue calling memory_region_allocate_system_memory() 
> *after* memory_region_init_ram() by the past?

I don't recall any, memory_region_init_ram() is essentially the same
as memory_region_allocate_system_memory() for most of emulated machines
(i.e. non-numa, no mem-path cases)

> Maybe not, or it is fixed, and your patch is fine:
> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Thanks!

> 
> > @@ -116,17 +117,17 @@ static void niagara_init(MachineState *machine)
> >       memory_region_add_subregion(sysmem, NIAGARA_PARTITION_RAM_BASE,
> >                                   &s->partition_ram);
> >   
> > -    memory_region_allocate_system_memory(&s->nvram, NULL,
> > -                                         "sun4v.nvram", NIAGARA_NVRAM_SIZE);
> > +    memory_region_init_ram(&s->nvram, NULL, "sun4v.nvram", NIAGARA_NVRAM_SIZE,
> > +                           &error_fatal);
> >       memory_region_add_subregion(sysmem, NIAGARA_NVRAM_BASE, &s->nvram);
> > -    memory_region_allocate_system_memory(&s->md_rom, NULL,
> > -                                         "sun4v-md.rom", NIAGARA_MD_ROM_SIZE);
> > +    memory_region_init_ram(&s->md_rom, NULL, "sun4v-md.rom",
> > +                           NIAGARA_MD_ROM_SIZE, &error_fatal);
> >       memory_region_add_subregion(sysmem, NIAGARA_MD_ROM_BASE, &s->md_rom);
> > -    memory_region_allocate_system_memory(&s->hv_rom, NULL,
> > -                                         "sun4v-hv.rom", NIAGARA_HV_ROM_SIZE);
> > +    memory_region_init_ram(&s->hv_rom, NULL, "sun4v-hv.rom",
> > +                           NIAGARA_HV_ROM_SIZE, &error_fatal);
> >       memory_region_add_subregion(sysmem, NIAGARA_HV_ROM_BASE, &s->hv_rom);
> > -    memory_region_allocate_system_memory(&s->prom, NULL,
> > -                                         "sun4v.prom", PROM_SIZE_MAX);
> > +    memory_region_init_ram(&s->prom, NULL, "sun4v.prom", PROM_SIZE_MAX,
> > +                           &error_fatal);
> >       memory_region_add_subregion(sysmem, NIAGARA_PROM_BASE, &s->prom);
> >   
> >       add_rom_or_fail("nvram1", NIAGARA_NVRAM_BASE);
> > @@ -143,8 +144,8 @@ static void niagara_init(MachineState *machine)
> >           BlockBackend *blk = blk_by_legacy_dinfo(dinfo);
> >           int size = blk_getlength(blk);
> >           if (size > 0) {
> > -            memory_region_allocate_system_memory(&s->vdisk_ram, NULL,
> > -                                                 "sun4v_vdisk.ram", size);
> > +            memory_region_init_ram(&s->vdisk_ram, NULL, "sun4v_vdisk.ram", size,
> > +                                   &error_fatal);
> >               memory_region_add_subregion(get_system_memory(),
> >                                           NIAGARA_VDISK_BASE, &s->vdisk_ram);
> >               dinfo->is_default = 1;
> >   
>