From: Serge Semin <Sergey.Semin@baikalelectronics.ru>
To: Miquel Raynal <miquel.raynal@bootlin.com>
Cc: Serge Semin <fancer.lancer@gmail.com>,
kernel test robot <lkp@intel.com>, <kbuild-all@lists.01.org>,
<linux-kernel@vger.kernel.org>, <linux-mtd@lists.infradead.org>
Subject: Re: drivers/mtd/maps/physmap-bt1-rom.c:78:18: sparse: sparse: cast removes address space '__iomem' of expression
Date: Wed, 11 Nov 2020 22:22:59 +0300 [thread overview]
Message-ID: <20201111192259.ovdyjcuue7fx2bqa@mobilestation> (raw)
In-Reply-To: <20201110163556.3e3423f6@xps13>
On Tue, Nov 10, 2020 at 04:35:56PM +0100, Miquel Raynal wrote:
> Hi Serge,
>
> Serge Semin <Sergey.Semin@baikalelectronics.ru> wrote on Tue, 10 Nov
> 2020 14:38:27 +0300:
>
> > Hello Miquel,
> >
> > A situation noted by the warning below won't cause any problem because
> > the casting is done to a non-dereferenced variable. It is utilized
> > as a pointer bias later in that function. Shall we just ignore the
> > warning or still fix it somehow?
>
> Do you think the cast to a !__iomem value is mandatory here?
It's not mandatory to have the casting with no __iomem, but wouldn't
doing like this:
+ shift = (ssize_t __iomem)src & 0x3;
be looking weird? Really, is there a good way to somehow extract the first
two bits of a __iomem pointer without getting the sparse warning?
-Sergey
>
> Perhaps if you find an elegant wait to avoid the warning it would be
> nice, otherwise I guess we'll let it aside as a false positive.
>
> Cheers,
> Miquèl
next prev parent reply other threads:[~2020-11-11 19:23 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-11-02 4:42 drivers/mtd/maps/physmap-bt1-rom.c:78:18: sparse: sparse: cast removes address space '__iomem' of expression kernel test robot
2020-11-10 11:38 ` Serge Semin
2020-11-10 15:35 ` Miquel Raynal
2020-11-11 19:22 ` Serge Semin [this message]
2020-11-12 8:27 ` Miquel Raynal
2020-11-12 11:20 ` Serge Semin
2020-11-12 15:00 ` Vignesh Raghavendra
2020-11-12 15:27 ` Serge Semin
2020-11-12 15:43 ` Miquel Raynal
2020-11-12 16:10 ` Serge Semin
2020-11-12 16:15 ` Miquel Raynal
2020-11-12 16:21 ` Serge Semin
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