Re: [PATCH 2/2] reboot: fix parsing of reboot cpu number

[Pavel Tatashin]

On Fri, Oct 16, 2020 at 2:09 PM Matteo Croce <mcroce@xxxxxxxxxxxxxxxxxxx> wrote:
>
> From: Matteo Croce <mcroce@xxxxxxxxxxxxx>
>
> The kernel cmdline reboot= argument allows to specify the CPU used
> for rebooting, with the syntax `s####` among the other flags, e.g.
>
>   reboot=soft,s4
>   reboot=warm,s31,force
>
> In the early days the parsing was done with simple_strtoul(), later
> deprecated in favor of the safer kstrtoint() which handles overflow.
>
> But kstrtoint() returns -EINVAL if there are non-digit characters
> in a string, so if this flag is not the last given, it's silently
> ignored as well as the subsequent ones.
>
> To fix it, revert the usage of simple_strtoul(), which is no longer
> deprecated, and restore the old behaviour.
>
> While at it, merge two identical code blocks into one.
>
> Fixes: 616feab75397 ("kernel/reboot.c: convert simple_strtoul to kstrtoint")
> Signed-off-by: Matteo Croce <mcroce@xxxxxxxxxxxxx>

Reviewed-by: Pavel Tatashin <pasha.tatashin@xxxxxxxxxx>