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Date: Thu, 10 Oct 2013 18:29:45 +0300
From: Eli Cohen <eli@dev.mellanox.co.il>
To: Alexander Gordeev <agordeev@redhat.com>
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Subject: Re: [PATCH RFC 50/77] mlx5: Update MSI/MSI-X interrupts enablement
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On Thu, Oct 03, 2013 at 09:48:39PM +0200, Alexander Gordeev wrote:
> 
> pci_enable_msix() may fail, but it can not return a positive number.
>

That is true according to the current logic but the comment on top of
pci_enable_msix() still says:
"A return of < 0 indicates a failure.  Or a return of > 0 indicates
that driver request is exceeding the number of irqs or MSI-X vectors
available"

So you're counting on an implementation that may change in the future.
I think leaving the code as it is now is safer.