Hi Breno,
Breno Leitao <lei...@debian.org> writes:
> Function xive_native_get_ipi() might uses chip_id without it being
> initialized. This gives the following error on 'smatch' tool:
>
> error: uninitialized symbol 'chip_id'
Which is correct, it can be used uninitialised. I'm surprised GCC
doesn't warn about it.
> This patch simply sets chip_id initial value to 0.
I'd prefer we fixed it differently, by explicitly initialising to zero
at the appropriate place in the code.
> diff --git a/arch/powerpc/sysdev/xive/native.c
> b/arch/powerpc/sysdev/xive/native.c
> index 311185b9960a..fc56673a3c0f 100644
> --- a/arch/powerpc/sysdev/xive/native.c
> +++ b/arch/powerpc/sysdev/xive/native.c
> @@ -239,7 +239,7 @@ static bool xive_native_match(struct device_node *node)
> static int xive_native_get_ipi(unsigned int cpu, struct xive_cpu *xc)
> {
> struct device_node *np;
> - unsigned int chip_id;
> + unsigned int chip_id = 0;
> s64 irq;
>
> /* Find the chip ID */
The current code is:
/* Find the chip ID */
np = of_get_cpu_node(cpu, NULL);
if (np) {
if (of_property_read_u32(np, "ibm,chip-id", &chip_id) < 0)
chip_id = 0;
}
Where if np is NULL then we don't initialise chip_id.
Which could be:
np = of_get_cpu_node(cpu, NULL);
if (of_property_read_u32(np, "ibm,chip-id", &chip_id) < 0)
chip_id = 0;
Because of_property_read_u32() will just return an error if np is NULL.
It's also missing an of_node_put() of np, you should do a separate patch
to fix that. You can just do it unconditionally after the
of_property_read_u32().
cheers
