Re: [PATCH v4 03/13] media: pci: cx18-av-vbi: Replace open-coded parity calculation with parity_odd()

Kuan-Wei Chiu <[email protected]> Sat, 12 Apr 2025 00:37:23 +0800

Newsgroups	dev.linux.lists.brcm80211,org.freedesktop.lists.dri-devel,org.infradead.lists.linux-i3c,org.infradead.lists.linux-mtd,org.kernel.vger.bpf,org.kernel.vger.linux-hwmon,org.kernel.vger.linux-input,org.kernel.vger.linux-kernel,org.kernel.vger.linux-media,org.kernel.vger.linux-serial,org.kernel.vger.linux-wireless,org.kernel.vger.netdev
Message-ID	<Z/lFQ85vhSQiFDBm@visitorckw-System-Product-Name>

On Thu, Apr 10, 2025 at 07:08:58AM +0200, Arend Van Spriel wrote:
> On April 10, 2025 12:06:52 AM Johannes Berg <[email protected]> wrote:
> 
> > On Wed, 2025-04-09 at 20:43 +0200, Arend van Spriel wrote:
> > > 
> > > This is orthogonal to the change to parity_odd() though. More specific
> > > to the new parity_odd() you can now do following as parity_odd()
> > > argument is u64:
> > > 
> > > err = !parity_odd(*(u16 *)p);
> > 
> > Can it though? Need to be careful with alignment with that, I'd think.
> 
> My bad. You are absolutely right.
> 
Then maybe we can still go with:

	err = !parity_odd(p[0] ^ p[1]);

I believe this should still be a fairly safe approach?

Regards,
Kuan-Wei