From: "Michael S. Tsirkin" <mst@redhat.com>
To: Wei Wang <wei.w.wang@intel.com>
Cc: virtualization@lists.linux-foundation.org
Subject: Re: [PATCH 1/2] virtio-balloon: initialize all vq callbacks
Date: Wed, 18 Dec 2019 00:19:57 -0500 [thread overview]
Message-ID: <20191218001922-mutt-send-email-mst@kernel.org> (raw)
In-Reply-To: <5DF99A95.8050800@intel.com>
On Wed, Dec 18, 2019 at 11:18:45AM +0800, Wei Wang wrote:
> On 12/18/2019 03:06 AM, Daniel Verkamp wrote:
> > Ensure that elements of the array that correspond to unavailable
> > features are set to NULL; previously, they would be left uninitialized.
> >
> > Since the corresponding names array elements were explicitly set to
> > NULL, the uninitialized callback pointers would not actually be
> > dereferenced; however, the uninitialized callbacks elements would still
> > be read in vp_find_vqs_msix() and used to calculate the number of MSI-X
> > vectors required.
>
> With your 2nd patch:
> if (names[i] && callbacks[i])
> ++nvectors;
>
> It seems this patch isn't necessary as names[i] is already NULL, isn't it?
>
> Best,
> Wei
Right but passing uninitialized values isn't nice even if
the function called happens to ignore them.
next prev parent reply other threads:[~2019-12-18 5:19 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-12-17 19:06 [PATCH 1/2] virtio-balloon: initialize all vq callbacks Daniel Verkamp
2019-12-17 19:06 ` [PATCH 2/2] virtio-pci: check name when counting MSI-X vectors Daniel Verkamp
2019-12-17 20:04 ` Michael S. Tsirkin
2019-12-18 5:19 ` Michael S. Tsirkin
2019-12-18 9:30 ` Cornelia Huck
2019-12-17 20:05 ` [PATCH 1/2] virtio-balloon: initialize all vq callbacks Michael S. Tsirkin
2019-12-17 20:10 ` Daniel Verkamp
2019-12-18 3:18 ` Wei Wang
2019-12-18 5:19 ` Michael S. Tsirkin [this message]
2019-12-18 6:06 ` Wei Wang
2019-12-18 9:28 ` Cornelia Huck
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