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From: Paolo Bonzini <pbonzini@redhat.com>
Date: Fri, 26 Jan 2024 19:11:40 +0100
Message-ID: <CABgObfZe3JWv=zsVoRwgERNzVYLUet8LpRhj_sbh4Mg=zbwsNA@mail.gmail.com>
Subject: Re: Re: Re: [PATCH] KVM: x86: Check irqchip mode before create PIT
To: Sean Christopherson <seanjc@google.com>
Cc: Brilliant Hanabi <moehanabichan@gmail.com>, bp@alien8.de, dave.hansen@linux.intel.com, 
	hpa@zytor.com, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, 
	mingo@redhat.com, tglx@linutronix.de, x86@kernel.org
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On Thu, Jan 25, 2024 at 12:59=E2=80=AFAM Sean Christopherson <seanjc@google=
com> wrote:
> On Thu, Jan 25, 2024, Brilliant Hanabi wrote:
> > Thanks for your review. In my opinion, it is better to avoid potential =
bugs
> > which is difficult to detect, as long as you can return errors to let
> > developers know about them in advance, although the kernel is not to bl=
ame
> > for this bug.
>
> Oh, I completely agree that explict errors are far better.  My only conce=
rn is
> that there's a teeny tiny chance that rejecting an ioctl() that used to w=
ork
> could break userspace.
>
> Go ahead and send v2.  I'll get Paolo's thoughts on whether or not this i=
s likely
> to break userspace and we can go from there.

I share the same worry but I agree it's quite unlikely.  Let's just do
it, and if someone complains we'll revert it.

Paolo