[libvirt PATCH 4/4] qemu: increase locked memory limit when a vDPA device is present

[Daniel Henrique Barboza]

On 3/23/21 3:50 PM, Laine Stump wrote:
> Just like VFIO devices, vDPA devices may need to have all guest memory
> pages locked/pinned in order to operate properly. In the case of VFIO
> devices (including mdev and NVME, which also use VFIO) libvirt
> automatically increases the locked memory limit when one of those
> devices is present. This patch modifies that code to also increase the
> limit if there are any vDPA devices present.
> 
> Resolves: https://bugzilla.redhat.com/1939776
> Signed-off-by: Laine Stump <laine at redhat.com>
> ---

Reviewed-by: Daniel Henrique Barboza <danielhb413 at gmail.com>

>   src/qemu/qemu_domain.c | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c
> index e0379e81ba..76e8903dbc 100644
> --- a/src/qemu/qemu_domain.c
> +++ b/src/qemu/qemu_domain.c
> @@ -9199,7 +9199,7 @@ getPPC64MemLockLimitBytes(virDomainDefPtr def,
>           passthroughLimit = maxMemory +
>                              128 * (1ULL<<30) / 512 * nPCIHostBridges +
>                              8192;
> -    } else if (forceVFIO || qemuDomainNeedsVFIO(def)) {
> +    } else if (forceVFIO || qemuDomainNeedsVFIO(def) || virDomainDefHasVDPANet(def)) {
>           /* For regular (non-NVLink2 present) VFIO passthrough, the value
>            * of passthroughLimit is:
>            *
> @@ -9289,7 +9289,7 @@ qemuDomainGetMemLockLimitBytes(virDomainDefPtr def,
>        *
>        * Note that this may not be valid for all platforms.
>        */
> -    if (forceVFIO || qemuDomainNeedsVFIO(def))
> +    if (forceVFIO || qemuDomainNeedsVFIO(def) || virDomainDefHasVDPANet(def))
>           memKB = virDomainDefGetMemoryTotal(def) + 1024 * 1024;
>   
>       return memKB << 10;
>