Re: [PATCH] kvm: no need to check return value of debugfs_create functions

From: Greg Kroah-Hartman
Date: Tue Jan 22 2019 - 13:40:20 EST


On Tue, Jan 22, 2019 at 09:29:07AM -0800, Sean Christopherson wrote:
> On Tue, Jan 22, 2019 at 09:21:02AM -0800, Sean Christopherson wrote:
> > On Tue, Jan 22, 2019 at 04:21:50PM +0100, Greg Kroah-Hartman wrote:
> > > When calling debugfs functions, there is no need to ever check the
> > > return value. The function can work or not, but the code logic should
> > > never do something different based on this.
> >
> > What about wanting to make the debugfs all-or-nothing? That seems like
> > a legitimate usage of checking the return value.
> >
> > E.g. KVM removes the debugfs if kvm_arch_create_vcpu_debugfs() fails, and
> > the arch/x86/kvm/debugfs.c implementation of kvm_arch_create_vcpu_debugfs()
> > returns an error if any of its debugfs_create_file() calls fail.
> >
> > If you're adamant about removing all debugfs create return value checks,
> > the aforementioned debugfs_create_file() calls should also be removed.
> > And at that point kvm_create_vcpu_debugfs() should have a 'void' return
> > value.
>
> Belatedly saw the other series. It'll require a bit more coordination,
> but folding this into the x86 series would allow for converting the KVM
> call stack to have 'void' returns.

Oh, nice, want me to tack this onto the end of there, or just do some
follow-on patches after this gets merged?

thanks,

greg k-h