Coverity complains of unsigned compare against 0. There are 2 cases in
this function:
1821 itp = (irq_holdoff * 1000) / p->desc->qman_256_cycles_per_ns;
CID 121131 (#1 of 1): Unsigned compared against 0 (NO_EFFECT)
unsigned_compare: This less-than-zero comparison of an unsigned value is never
true. itp < 0U.
1822 if (itp < 0 || itp > 4096) {
1823 max_holdoff = (p->desc->qman_256_cycles_per_ns * 4096) /
1000;
1824 pr_err("irq_holdoff must be between 0..%dus\n",
max_holdoff);
1825 return -EINVAL;
1826 }
1827
unsigned_compare: This less-than-zero comparison of an unsigned value
is never true. irq_threshold < 0U.
1828 if (irq_threshold >= p->dqrr.dqrr_size || irq_threshold < 0) {
1829 pr_err("irq_threshold must be between 0..%d\n",
1830 p->dqrr.dqrr_size - 1);
1831 return -EINVAL;
1832 }
Fix this by removing the comparisons altogether as they are incorrect. Zero is
a possible value in either case. Also fix a minor comment typo and update the
2 pr_err() calls to use %u formatting as well as be more precise regarding
the exact error.
Fixes: ed1d2143fee5 ("soc: fsl: dpio: add support for irq coalescing per
software portal")
Cc: Ioana Ciornei <[email protected]>
Cc: Roy Pledge <[email protected]>
Cc: Li Yang <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Signed-off-by: Tim Gardner <[email protected]>
---
v1 - check itp and irq_threshold for 0.
v2 - drop the checks for comparison to 0. Update pr_err() calls with precise
language
about the error.
---
drivers/soc/fsl/dpio/qbman-portal.c | 11 +++++------
1 file changed, 5 insertions(+), 6 deletions(-)
diff --git a/drivers/soc/fsl/dpio/qbman-portal.c
b/drivers/soc/fsl/dpio/qbman-portal.c
index d3c58df6240d..3474bf5f88d5 100644
--- a/drivers/soc/fsl/dpio/qbman-portal.c
+++ b/drivers/soc/fsl/dpio/qbman-portal.c
@@ -1816,18 +1816,17 @@ int qbman_swp_set_irq_coalescing(struct qbman_swp *p,
u32 irq_threshold,
u32 itp, max_holdoff;
/* Convert irq_holdoff value from usecs to 256 QBMAN clock cycles
- * increments. This depends to the QBMAN internal frequency.
+ * increments. This depends on the QBMAN internal frequency.
*/
itp = (irq_holdoff * 1000) / p->desc->qman_256_cycles_per_ns;
- if (itp < 0 || itp > 4096) {
+ if (itp > 4096) {
max_holdoff = (p->desc->qman_256_cycles_per_ns * 4096) / 1000;
- pr_err("irq_holdoff must be between 0..%dus\n", max_holdoff);
+ pr_err("irq_holdoff must be <= %uus\n", max_holdoff);
return -EINVAL;
}
- if (irq_threshold >= p->dqrr.dqrr_size || irq_threshold < 0) {
- pr_err("irq_threshold must be between 0..%d\n",
- p->dqrr.dqrr_size - 1);
+ if (irq_threshold >= p->dqrr.dqrr_size) {
+ pr_err("irq_threshold must be < %u\n", p->dqrr.dqrr_size - 1);
return -EINVAL;
}
--
2.33.1
