Re: [PATCH 4/6] input/vmmouse: Use vmware_hypercall API

From: dmitry.torokhov@xxxxxxxxx
Date: Fri Nov 24 2023 - 23:58:38 EST


On Sat, Nov 25, 2023 at 01:22:58AM +0000, Alexey Makhalov wrote:
> On Nov 24, 2023, at 11:46 AM, Simon Horman <horms@xxxxxxxxxx> wrote:
> >
> > On Wed, Nov 22, 2023 at 03:30:49PM -0800, Alexey Makhalov wrote:
> >> Switch from VMWARE_HYPERCALL macro to vmware_hypercall API.
> >> Eliminate arch specific code. No functional changes intended.
> >>
> >> Signed-off-by: Alexey Makhalov <amakhalov@xxxxxxxxxx>
> >
> > Hi Alexey,
> >
> > it is not strictly related to this patch, but I notice than an x86_64
> > allmodconfig build with W=1 using gcc-13 fails to compile this file.
> >
> > It appears that the problem relates to both priv->phys and
> > psmouse->ps2dev.serio->phys being 32 bytes.
> >
> >
> > drivers/input/mouse/vmmouse.c: In function ‘vmmouse_init’:
> > drivers/input/mouse/vmmouse.c:455:53: error: ‘/input1’ directive output may be truncated writing 7 bytes into a region of size between 1 and 32 [-Werror=format-truncation=]
> > 455 | snprintf(priv->phys, sizeof(priv->phys), "%s/input1",
> > | ^~~~~~~
> > drivers/input/mouse/vmmouse.c:455:9: note: ‘snprintf’ output between 8 and 39 bytes into a destination of size 32
> > 455 | snprintf(priv->phys, sizeof(priv->phys), "%s/input1",
> > | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> > 456 | psmouse->ps2dev.serio->phys);
> > | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> >
> > ...
>
> Hi Simon, thanks for reporting the issue.
> Zack, please take a look.

We want the truncation behavior and we do not want GCC to make noise
about these, that is why "format-truncation" is explicitly disabled for
normal compiles. I guess we should exclude it even when we compile with
W=1 instead of doing pointless changes in the drivers.

Thanks.

--
Dmitry