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Date:   Fri, 04 Aug 2023 17:57:57 +0000
In-Reply-To: <ZM0rXgKvb912k5BE@linux.dev> (message from Oliver Upton on Fri, 4
 Aug 2023 16:46:22 +0000)
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Message-ID: <gsnto7jm8zbu.fsf@coltonlewis-kvm.c.googlers.com>
Subject: Re: [PATCH 2/4] KVM: selftests: Add helper macros for ioctl()s that
 return file descriptors
From:   Colton Lewis <coltonlewis@google.com>
To:     Oliver Upton <oliver.upton@linux.dev>
Cc:     seanjc@google.com, maz@kernel.org,
        linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev,
        linux-kernel@vger.kernel.org, mhal@rbox.co
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Oliver Upton <oliver.upton@linux.dev> writes:

> Hi Sean,

> On Thu, Aug 03, 2023 at 05:42:24PM -0700, Sean Christopherson wrote:
>> Add KVM, VM, and vCPU scoped helpers for ioctl()s that return file
>> descriptors, i.e. deduplicate code for asserting success on ioctls() for
>> which a positive return value, not just zero, is considered success.

>> Signed-off-by: Sean Christopherson <seanjc@google.com>

> I appreciate the desire to eliminate duplicate code, but I think the
> naming just muddies the waters. TBH, when I first read the diff w/o the
> changelog, I thought you were describing the input fd (i.e. 'kvm_fd',
> 'vm_fd', 'vcpu_fd'). I don't think explicitly spelling out the condition
> each time (i.e. ret >= 0) is all that difficult.

Couldn't ret >= 0 be the assert condition for everything? Don't see why
there needs to be different helpers to check == 0 and >= 0.

Unless I'm missing something, error returns are only ever negative.