On Fri, Aug 23, 2024 at 08:46:12AM +0800, Zijun Hu wrote:
> On 2024/8/23 08:02, Dmitry Torokhov wrote:
> > Hi,
> >
> > On Fri, Aug 23, 2024 at 07:46:09AM +0800, Zijun Hu wrote:
> >> From: Zijun Hu <quic_zijuhu@xxxxxxxxxxx>
> >>
> >> An uninitialized variable @data.have_async may be used as analyzed
> >> by the following inline comments:
> >>
> >> static int __device_attach(struct device *dev, bool allow_async)
> >> {
> >> // if @allow_async is true.
> >>
> >> ...
> >> struct device_attach_data data = {
> >> .dev = dev,
> >> .check_async = allow_async,
> >> .want_async = false,
> >> };
> >> // @data.have_async is not initialized.
> >
> > No, in the presence of a structure initializer fields not explicitly
> > initialized will be set to 0 by the compiler.
> >
> really?
> do all C compilers have such behavior ?
Oh wait, if this were static, then yes, it would all be set to 0, sorry,
I misread this.
This is on the stack so it needs to be zeroed out explicitly. We should
set the whole thing to 0 and then set only the fields we want to
override to ensure it's all correct.
thanks,
greg k-h
