Re: [PATCH] hostmem: don't use mbind() if host-nodes is epmty

[Philippe Mathieu-Daudé]

On 5/11/20 9:24 PM, Igor Mammedov wrote:
> On Mon, 11 May 2020 18:00:01 +0200
> Philippe Mathieu-Daudé <address@hidden> wrote:
>
> > Hi Eduardo,
> >
> > On 5/4/20 5:44 PM, Eduardo Habkost wrote:
> > > On Thu, Apr 30, 2020 at 11:46:06AM -0400, Igor Mammedov wrote:
> > > > Since 5.0 QEMU uses hostmem backend for allocating main guest RAM.
> > > > The backend however calls mbind() which is typically NOP
> > > > in case of default policy/absent host-nodes bitmap.
> > > > However when runing in container with black-listed mbind()
> > > > syscall, QEMU fails to start with error
> > > >    "cannot bind memory to host NUMA nodes: Operation not permitted"
> > > > even when user hasn't provided host-nodes to pin to explictly
> > > > (which is the case with -m option)
> > > >
> > > > To fix issue, call mbind() only in case when user has provided
> > > > host-nodes explicitly (i.e. host_nodes bitmap is not empty).
> > > > That should allow to run QEMU in containers with black-listed
> > > > mbind() without memory pinning. If QEMU provided memory-pinning
> > > > is required user still has to white-list mbind() in container
> > > > configuration.
> > > >
> > > > Reported-by: Manuel Hohmann <address@hidden>
> > > > Signed-off-by: Igor Mammedov <address@hidden>
> > >
> > > Queued on machine-next, thanks!
> >
> > I've been debugging this issue again today and figured it was not
> > merged, if possible can you add the "Cc: address@hidden" tag
> > before sending your pull request?
> it's CCed already, so my impression was that will should picked up once it was 
> reviewed.

Correct, however some distributions find easier to grep for the 'Cc: 
address@hidden' merged tag before qemu-stable is released.

> > Thanks,
> >
> > Phil.