[PATCH v2] platform/x86/intel/tpmi/plr: Fix output in plr_print_bits()

From: Dan Carpenter
Date: Mon Jul 15 2024 - 16:23:08 EST


Smatch complains that 'str' can be used without being initialized:

drivers/platform/x86/intel/intel_plr_tpmi.c:178 plr_print_bits()
error: uninitialized symbol 'str'.

In this loop, we iterate over all the set bits and print the name of the
bit. The intention is that if there is a bit which is between 0-31 we
look for the name in the first array plr_coarse_reasons[] which has 10
elements. If the bit is in the 32-63 range we look for it in the
plr_fine_reasons[] array which has 30 elements. If the bit is in the
invalid ranges, 10-31 or 62-63, then we should print "UNKNOWN(%d)".

The problem is that 'str' needs to be initialized at the start of each
iteration, otherwise if we can't find the string then instead of printing
"UNKNOWN(%d)", we will re-print whatever the previous bit was.

Fixes: 9e9397a41b7b ("platform/x86/intel/tpmi/plr: Add support for the plr mailbox")
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
---
v2: initialize str at the start of each iteration

drivers/platform/x86/intel/intel_plr_tpmi.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/platform/x86/intel/intel_plr_tpmi.c b/drivers/platform/x86/intel/intel_plr_tpmi.c
index c1aa52c23d25..69ace6a629bc 100644
--- a/drivers/platform/x86/intel/intel_plr_tpmi.c
+++ b/drivers/platform/x86/intel/intel_plr_tpmi.c
@@ -162,10 +162,11 @@ static int plr_clear_cpu_status(struct tpmi_plr_die *plr_die, int cpu)
static void plr_print_bits(struct seq_file *s, u64 val, int bits)
{
const unsigned long mask[] = { BITMAP_FROM_U64(val) };
- const char *str;
int bit, index;

for_each_set_bit(bit, mask, bits) {
+ const char *str = NULL;
+
if (bit < PLR_COARSE_REASON_BITS) {
if (bit < ARRAY_SIZE(plr_coarse_reasons))
str = plr_coarse_reasons[bit];
--
2.43.0