RE: [PATCH 11/17] iommu/vt-d: Fix operand size in bitwise operation

Zhang, Tina
2023-04-12T08:11:38Z

Hi David,

> -----Original Message-----
> From: David Laight <David.Laight@ACULAB.COM>
> Sent: Wednesday, April 12, 2023 3:11 PM
> To: 'Baolu Lu' <baolu.lu@linux.intel.com>; Joerg Roedel <joro@8bytes.org>
> Cc: Vinod Koul <vkoul@kernel.org>; Zhang, Tina <tina.zhang@intel.com>; Jacob
> Pan <jacob.jun.pan@linux.intel.com>; Christophe JAILLET
> <christophe.jaillet@wanadoo.fr>; iommu@lists.linux.dev; linux-
> kernel@vger.kernel.org
> Subject: RE: [PATCH 11/17] iommu/vt-d: Fix operand size in bitwise operation
>
> From: Baolu Lu
> > Sent: 12 April 2023 02:32
> >
> > On 4/12/23 5:22 AM, David Laight wrote:
> > >> Sent: 11 April 2023 07:48
> > >>
> > >> From: Tina Zhang<tina.zhang@intel.com>
> > >>
> > >> The patch fixes the klocwork issues that operands in a bitwise
> > >> operation have different size at line 1692 of dmar.c, line 1898 and
> > >> line 1907 of iommu.c.
> > > Why is this any kind of thing that needs fixing?
> >
> > This description is a bit misleading. Actually I queued it as a
> > cleanup patch.
>
> Hopefully without 'fix' anywhere in the description.
> Otherwise the scripts will pick it for a back-port.
Sure.

>
> > > - val |= (1 << 11) | 1;
> > > + val |= BIT_ULL(11) | BIT_ULL(0);
>
> More problematic it what is bit 11 anyway?
The magic number should be removed from here.

Regards,
-Tina
>
> David
>
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