Re: [Qemu-devel] [PATCH] Remove debugging messages.

[Richard W.M. Jones]

On Tue, Jul 19, 2011 at 11:49:22PM +0400, Michael Tokarev wrote:
> 19.07.2011 23:23, Richard W.M. Jones wrote:
> > From: "Richard W.M. Jones" <address@hidden>
> > 
> > When using qemu -machine accel=kvm:tcg, if KVM is not available you
> > get a load of debugging output:
> > 
> >   Could not access KVM kernel module: No such file or directory
> >   failed to initialize KVM: No such file or directory
> >   Back to tcg accelerator.
> > 
> > Signed-off-by: Richard W.M. Jones <address@hidden>
> > ---
> >  kvm-all.c |    1 -
> >  vl.c      |   14 --------------
> >  2 files changed, 0 insertions(+), 15 deletions(-)
> > 
> > diff --git a/kvm-all.c b/kvm-all.c
> > index cbc2532..35d698b 100644
> > --- a/kvm-all.c
> > +++ b/kvm-all.c
> > @@ -713,7 +713,6 @@ int kvm_init(void)
> >      s->vmfd = -1;
> >      s->fd = qemu_open("/dev/kvm", O_RDWR);
> >      if (s->fd == -1) {
> > -        fprintf(stderr, "Could not access KVM kernel module: %m\n");
> 
> Don't do this.  qemu error reporting sucks badly already,
> and this very error message gives us at least some details
> (the %m part) about what's missing.  There's no other place
> where this information is printed in case this open fails.
> We already have to resort to strace in way too many places... :(

This is an argument for having some sort of global --debug option.
Silent by default, but debug messages are a mere runtime flag away.

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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