| Message ID | 20211019121925.8910-1-tim.gardner@canonical.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 818a76a55d6e9e7ec7568ae580390e941da84b62 |
| Headers | show |
| Series | [v2,net-next] soc: fsl: dpio: Unsigned compared against 0 in qbman_swp_set_irq_coalescing() | expand |
| Context | Check | Description |
|---|---|---|
| netdev/cover_letter | success | Single patches do not need cover letters |
| netdev/fixes_present | success | Fixes tag not required for -next series |
| netdev/patch_count | success | Link |
| netdev/tree_selection | success | Clearly marked for net-next |
| netdev/subject_prefix | success | Link |
| netdev/cc_maintainers | success | CCed 4 of 4 maintainers |
| netdev/source_inline | success | Was 0 now: 0 |
| netdev/verify_signedoff | success | Signed-off-by tag matches author and committer |
| netdev/module_param | success | Was 0 now: 0 |
| netdev/build_32bit | success | Errors and warnings before: 0 this patch: 0 |
| netdev/kdoc | success | Errors and warnings before: 0 this patch: 0 |
| netdev/verify_fixes | success | Fixes tag looks correct |
| netdev/checkpatch | success | total: 0 errors, 0 warnings, 0 checks, 23 lines checked |
| netdev/build_allmodconfig_warn | success | Errors and warnings before: 0 this patch: 0 |
| netdev/header_inline | success | No static functions without inline keyword in header files |
On Tue, Oct 19, 2021 at 06:19:25AM -0600, Tim Gardner wrote: > 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 <ioana.ciornei@nxp.com> > Cc: Roy Pledge <Roy.Pledge@nxp.com> > Cc: Li Yang <leoyang.li@nxp.com> > Cc: linux-kernel@vger.kernel.org > Cc: linuxppc-dev@lists.ozlabs.org > Cc: linux-arm-kernel@lists.infradead.org > Cc: netdev@vger.kernel.org > Signed-off-by: Tim Gardner <tim.gardner@canonical.com> Tested-by: Ioana Ciornei <ioana.ciornei@nxp.com> Reviewed-by: Ioana Ciornei <ioana.ciornei@nxp.com> Thanks, -Ioana
Hello: This patch was applied to netdev/net-next.git (master) by David S. Miller <davem@davemloft.net>: On Tue, 19 Oct 2021 06:19:25 -0600 you wrote: > 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 } > > [...] Here is the summary with links: - [v2,net-next] soc: fsl: dpio: Unsigned compared against 0 in qbman_swp_set_irq_coalescing() https://git.kernel.org/netdev/net-next/c/818a76a55d6e You are awesome, thank you! -- Deet-doot-dot, I am a bot. https://korg.docs.kernel.org/patchwork/pwbot.html
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; }
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 <ioana.ciornei@nxp.com> Cc: Roy Pledge <Roy.Pledge@nxp.com> Cc: Li Yang <leoyang.li@nxp.com> Cc: linux-kernel@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-arm-kernel@lists.infradead.org Cc: netdev@vger.kernel.org Signed-off-by: Tim Gardner <tim.gardner@canonical.com> --- 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(-)