Re: [dpdk-dev] [PATCH] eal: fix argument to rte_bsf32_safe
From: Tyler Retzlaff <hidden>
Date: 2021-07-19 17:15:38
On Tue, Jul 13, 2021 at 01:12:21PM -0700, Stephen Hemminger wrote:
The first argument to rte_bsf32_safe was incorrectly declared as a 64 bit value. This function only correctly handles on 32 bit values and the underlying function rte_bsf32 only accepts 32 bit values. This was introduced when the safe version was added and probably cause by copy/paste from the 64 bit version.
there are multiple errors in this family of functions [1] both in usage and signatures. we previously discussed rolling all fixes up into a single patch and announcing an api break. a doc patch was submitted as per the process documented for breaking api but received no replies [2] i have a full patch that corrects the whole family if you would like to take it instead. contact me offline if you are interested. 1. http://mails.dpdk.org/archives/dev/2021-March/201590.html 2. http://mails.dpdk.org/archives/dev/2021-March/201868.html the change stand-alone is correct so Acked-By: Tyler Retzlaff <redacted>
quoted hunk ↗ jump to hunk
The bug passed silently under the radar until some other code was built with -Wall and -Wextra in C++ and C++ complains about the missing cast. Yes, this is a API signature change, but the original code was wrong. It is an inline so not an ABI change. Fixes: 4e261f551986 ("eal: add 64-bit bsf and 32-bit safe bsf functions") Cc: anatoly.burakov@intel.com Signed-off-by: Stephen Hemminger <stephen@networkplumber.org> --- lib/eal/include/rte_common.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)diff --git a/lib/eal/include/rte_common.h b/lib/eal/include/rte_common.h index d5a32c66a5fe..99eb5f1820ae 100644 --- a/lib/eal/include/rte_common.h +++ b/lib/eal/include/rte_common.h@@ -623,7 +623,7 @@ rte_bsf32(uint32_t v) * Returns 0 if ``v`` was 0, otherwise returns 1. */ static inline int -rte_bsf32_safe(uint64_t v, uint32_t *pos) +rte_bsf32_safe(uint32_t v, uint32_t *pos) { if (v == 0) return 0;-- 2.30.2