On Mon, Jul 22, 2019 at 02:05:12PM +1000, Michael Ellerman wrote:
> Nathan Chancellor <natechancellor@xxxxxxxxx> writes:
> > On Mon, Jun 03, 2019 at 03:11:58PM -0700, Nathan Chancellor wrote:
> >> When building with -Wsometimes-uninitialized, clang warns:
> >>
> >> drivers/pci/hotplug/rpaphp_core.c:243:14: warning: variable 'fndit' is
> >> used uninitialized whenever 'for' loop exits because its condition is
> >> false [-Wsometimes-uninitialized]
> >> for (j = 0; j < entries; j++) {
> >> ^~~~~~~~~~~
> >> drivers/pci/hotplug/rpaphp_core.c:256:6: note: uninitialized use occurs
> >> here
> >> if (fndit)
> >> ^~~~~
> >> drivers/pci/hotplug/rpaphp_core.c:243:14: note: remove the condition if
> >> it is always true
> >> for (j = 0; j < entries; j++) {
> >> ^~~~~~~~~~~
> >> drivers/pci/hotplug/rpaphp_core.c:233:14: note: initialize the variable
> >> 'fndit' to silence this warning
> >> int j, fndit;
> >> ^
> >> = 0
> >>
> >> fndit is only used to gate a sprintf call, which can be moved into the
> >> loop to simplify the code and eliminate the local variable, which will
> >> fix this warning.
> >>
> >> Link: https://github.com/ClangBuiltLinux/linux/issues/504
> >> Fixes: 2fcf3ae508c2 ("hotplug/drc-info: Add code to search ibm,drc-info property")
> >> Suggested-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
> >> Signed-off-by: Nathan Chancellor <natechancellor@xxxxxxxxx>
> >> ---
> >>
> >> v1 -> v2:
> >>
> >> * Eliminate fndit altogether by shuffling the sprintf call into the for
> >> loop and changing the if conditional, as suggested by Nick.
> >>
> >> drivers/pci/hotplug/rpaphp_core.c | 18 +++++++-----------
> >> 1 file changed, 7 insertions(+), 11 deletions(-)
> >>
> >> diff --git a/drivers/pci/hotplug/rpaphp_core.c b/drivers/pci/hotplug/rpaphp_core.c
> >> index bcd5d357ca23..c3899ee1db99 100644
> >> --- a/drivers/pci/hotplug/rpaphp_core.c
> >> +++ b/drivers/pci/hotplug/rpaphp_core.c
> >> @@ -230,7 +230,7 @@ static int rpaphp_check_drc_props_v2(struct device_node *dn, char *drc_name,
> >> struct of_drc_info drc;
> >> const __be32 *value;
> >> char cell_drc_name[MAX_DRC_NAME_LEN];
> >> - int j, fndit;
> >> + int j;
> >>
> >> info = of_find_property(dn->parent, "ibm,drc-info", NULL);
> >> if (info == NULL)
> >> @@ -245,17 +245,13 @@ static int rpaphp_check_drc_props_v2(struct device_node *dn, char *drc_name,
> >>
> >> /* Should now know end of current entry */
> >>
> >> - if (my_index > drc.last_drc_index)
> >> - continue;
> >> -
> >> - fndit = 1;
> >> - break;
> >> + /* Found it */
> >> + if (my_index <= drc.last_drc_index) {
> >> + sprintf(cell_drc_name, "%s%d", drc.drc_name_prefix,
> >> + my_index);
> >> + break;
> >> + }
> >> }
> >> - /* Found it */
> >> -
> >> - if (fndit)
> >> - sprintf(cell_drc_name, "%s%d", drc.drc_name_prefix,
> >> - my_index);
> >>
> >> if (((drc_name == NULL) ||
> >> (drc_name && !strcmp(drc_name, cell_drc_name))) &&
> >> --
> >> 2.22.0.rc3
> >>
> >
> > Hi all,
> >
> > Could someone please pick this up?
>
> I'll take it.
>
> I was expecting Bjorn to take it as a PCI patch, but I realise now that
> I merged that code in the first place so may as well take this too.
>
> I'll put it in my next branch once that opens next week.
Sorry, I should have done something with this. Did you take it,
Michael? I don't see it in -next and haven't figured out where to
look in your git tree, so I can't tell. Just let me know either way
so I know whether to drop this or apply it.
Bjorn
