Re: [PATCH v3 2/9] igvm: track memory regions

On 30.07.26 09:12, Ani Sinha wrote:
> From: Gerd Hoffmann <[email protected]>
>
> Memory regions added by the current IGVM needs to be tracked so that they can be
> freed when a new IGVM is loaded.
>
> Reviewed-by: Ani Sinha <[email protected]>
> Signed-off-by: Gerd Hoffmann <[email protected]>
> ---
>   backends/igvm-cfg.c            |  1 +
>   backends/igvm.c                | 20 ++++++++++++--------
>   include/system/igvm-internal.h |  6 ++++++
>   3 files changed, 19 insertions(+), 8 deletions(-)
>
> diff --git a/backends/igvm-cfg.c b/backends/igvm-cfg.c
> index e1f09855f6..38438a7b1e 100644
> --- a/backends/igvm-cfg.c
> +++ b/backends/igvm-cfg.c
> @@ -65,6 +65,7 @@ static void igvm_complete(UserCreatable *uc, Error **errp)
>       IgvmCfg *igvm = IGVM_CFG(uc);
>   
>       igvm->file = qigvm_file_init(igvm->filename, errp);
> +    QTAILQ_INIT(&igvm->memory_regions);
>   }
>   
>   OBJECT_DEFINE_TYPE_WITH_INTERFACES(IgvmCfg, igvm_cfg, IGVM_CFG, OBJECT,
> diff --git a/backends/igvm.c b/backends/igvm.c
> index 534032fed8..9e7c90d386 100644
> --- a/backends/igvm.c
> +++ b/backends/igvm.c
> @@ -220,7 +220,7 @@ static void *qigvm_prepare_memory(QIgvm *ctx, uint64_t addr, uint64_t size,
>                                     int region_identifier, Error **errp)
>   {
>       ERRP_GUARD();
> -    MemoryRegion *igvm_pages = NULL;
> +    IgvmMemoryRegion *imr = NULL;
>       Int128 gpa_region_size;
>       MemoryRegionSection mrs =
>           memory_region_find(get_system_memory(), addr, size);
> @@ -254,23 +254,27 @@ static void *qigvm_prepare_memory(QIgvm *ctx, uint64_t addr, uint64_t size,
>            */
>           g_autofree char *region_name =
>               g_strdup_printf("igvm.%X", region_identifier);
> -        igvm_pages = g_new0(MemoryRegion, 1);
> +        imr = g_new0(IgvmMemoryRegion, 1);
> +        imr->mr = g_new0(MemoryRegion, 1);
>           if (ctx->machine_state->cgs &&
>               ctx->machine_state->cgs->require_guest_memfd) {
> -            if (!memory_region_init_ram_guest_memfd(igvm_pages, NULL,
> +            if (!memory_region_init_ram_guest_memfd(imr->mr, NULL,


Please make sure to track them with owner set to 
OBJECT(ctx->machine_state). Without owner, reference counting is 
disabled and we end up leaking memory regions on cleanup you introduce 
in patch 3 later.


Alex