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

["Philippe Mathieu-Daudé" <philmd@redhat.com>]

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

> @@ -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;
>