Re: [PATCH] firmware: arm_scmi: fix notifications macros argument reuse
From: Cristian Marussi
Date: Mon Jul 06 2020 - 09:20:53 EST
Hi
On Sat, Jul 04, 2020 at 07:01:21AM +0800, kernel test robot wrote:
> Hi Cristian,
>
> Thank you for the patch! Perhaps something to improve:
>
> [auto build test WARNING on next-20200630]
> [cannot apply to linux/master soc/for-next linus/master v5.8-rc3 v5.8-rc2 v5.8-rc1 v5.8-rc3]
> [If your patch is applied to the wrong git tree, kindly drop us a note.
> And when submitting patch, we suggest to use as documented in
> https://git-scm.com/docs/git-format-patch]
>
> url: https://github.com/0day-ci/linux/commits/Cristian-Marussi/firmware-arm_scmi-fix-notifications-macros-argument-reuse/20200701-002818
> base: f2b92b14533e646e434523abdbafddb727c23898
> compiler: gcc-9 (Debian 9.3.0-14) 9.3.0
>
> If you fix the issue, kindly add following tag as appropriate
> Reported-by: kernel test robot <lkp@xxxxxxxxx>
>
>
This patch was afterwards squashed into the SCMI Notifications series V11:
https://lore.kernel.org/linux-arm-kernel/20200701155348.52864-1-cristian.marussi@xxxxxxx/
and requeued on next, and, as I can see all of the surrounding/offending code
referenced in this report has been modified in V11 so I don' expect the reported
issues to be anymore valid...but let's wait to see the next CI run results on
next- to be sure about that :D (a local SMATCH/sparse run returned me no issues on V11)
Thanks
Cristian
> cppcheck warnings: (new ones prefixed by >>)
>
> drivers/firmware/arm_scmi/notify.c:660:9: warning: Identical condition 'ret', second condition is always false [identicalConditionAfterEarlyExit]
> return ret;
> ^
> drivers/firmware/arm_scmi/notify.c:654:6: note: first condition
> if (ret)
> ^
> drivers/firmware/arm_scmi/notify.c:660:9: note: second condition
> return ret;
> ^
> >> drivers/firmware/arm_scmi/notify.c:1125:9: warning: Variable 'r' is reassigned a value before the old one has been used. [redundantAssignment]
> r = REVT_NOTIFY_ENABLE(r_evt,
> ^
> drivers/firmware/arm_scmi/notify.c:1125:7: note: Variable 'r' is reassigned a value before the old one has been used.
> r = REVT_NOTIFY_ENABLE(r_evt,
> ^
> drivers/firmware/arm_scmi/notify.c:1125:9: note: Variable 'r' is reassigned a value before the old one has been used.
> r = REVT_NOTIFY_ENABLE(r_evt,
> ^
>
> vim +/r +1125 drivers/firmware/arm_scmi/notify.c
>
> 7a57069e9daf95a Cristian Marussi 2020-06-19 1090
> 5b352c5379300ec Cristian Marussi 2020-06-19 1091 /**
> 5b352c5379300ec Cristian Marussi 2020-06-19 1092 * __scmi_enable_evt() - Enable/disable events generation
> 5b352c5379300ec Cristian Marussi 2020-06-19 1093 * @r_evt: The registered event to act upon
> 5b352c5379300ec Cristian Marussi 2020-06-19 1094 * @src_id: The src_id to act upon
> 5b352c5379300ec Cristian Marussi 2020-06-19 1095 * @enable: The action to perform: true->Enable, false->Disable
> 5b352c5379300ec Cristian Marussi 2020-06-19 1096 *
> 5b352c5379300ec Cristian Marussi 2020-06-19 1097 * Takes care of proper refcounting while performing enable/disable: handles
> 5b352c5379300ec Cristian Marussi 2020-06-19 1098 * the special case of ALL sources requests by itself.
> 5b352c5379300ec Cristian Marussi 2020-06-19 1099 *
> 5b352c5379300ec Cristian Marussi 2020-06-19 1100 * Return: True when the required action has been successfully executed
> 5b352c5379300ec Cristian Marussi 2020-06-19 1101 */
> 5b352c5379300ec Cristian Marussi 2020-06-19 1102 static inline bool __scmi_enable_evt(struct scmi_registered_event *r_evt,
> 5b352c5379300ec Cristian Marussi 2020-06-19 1103 u32 src_id, bool enable)
> 5b352c5379300ec Cristian Marussi 2020-06-19 1104 {
> 5b352c5379300ec Cristian Marussi 2020-06-19 1105 int ret = 0;
> 5b352c5379300ec Cristian Marussi 2020-06-19 1106 u32 num_sources;
> 5b352c5379300ec Cristian Marussi 2020-06-19 1107 refcount_t *sid;
> 5b352c5379300ec Cristian Marussi 2020-06-19 1108
> 5b352c5379300ec Cristian Marussi 2020-06-19 1109 if (src_id == SRC_ID_MASK) {
> 5b352c5379300ec Cristian Marussi 2020-06-19 1110 src_id = 0;
> 5b352c5379300ec Cristian Marussi 2020-06-19 1111 num_sources = r_evt->num_sources;
> 5b352c5379300ec Cristian Marussi 2020-06-19 1112 } else if (src_id < r_evt->num_sources) {
> 5b352c5379300ec Cristian Marussi 2020-06-19 1113 num_sources = 1;
> 5b352c5379300ec Cristian Marussi 2020-06-19 1114 } else {
> 5b352c5379300ec Cristian Marussi 2020-06-19 1115 return ret;
> 5b352c5379300ec Cristian Marussi 2020-06-19 1116 }
> 5b352c5379300ec Cristian Marussi 2020-06-19 1117
> 5b352c5379300ec Cristian Marussi 2020-06-19 1118 mutex_lock(&r_evt->sources_mtx);
> 5b352c5379300ec Cristian Marussi 2020-06-19 1119 if (enable) {
> 5b352c5379300ec Cristian Marussi 2020-06-19 1120 for (; num_sources; src_id++, num_sources--) {
> 5b352c5379300ec Cristian Marussi 2020-06-19 1121 bool r;
> 5b352c5379300ec Cristian Marussi 2020-06-19 1122
> 5b352c5379300ec Cristian Marussi 2020-06-19 1123 sid = &r_evt->sources[src_id];
> 5b352c5379300ec Cristian Marussi 2020-06-19 1124 if (refcount_read(sid) == 0) {
> 5b352c5379300ec Cristian Marussi 2020-06-19 @1125 r = REVT_NOTIFY_ENABLE(r_evt,
> 5b352c5379300ec Cristian Marussi 2020-06-19 1126 r_evt->evt->id, src_id);
> 5b352c5379300ec Cristian Marussi 2020-06-19 1127 if (r)
> 5b352c5379300ec Cristian Marussi 2020-06-19 1128 refcount_set(sid, 1);
> 5b352c5379300ec Cristian Marussi 2020-06-19 1129 } else {
> 5b352c5379300ec Cristian Marussi 2020-06-19 1130 refcount_inc(sid);
> 5b352c5379300ec Cristian Marussi 2020-06-19 1131 r = true;
> 5b352c5379300ec Cristian Marussi 2020-06-19 1132 }
> 5b352c5379300ec Cristian Marussi 2020-06-19 1133 ret += r;
> 5b352c5379300ec Cristian Marussi 2020-06-19 1134 }
> 5b352c5379300ec Cristian Marussi 2020-06-19 1135 } else {
> 5b352c5379300ec Cristian Marussi 2020-06-19 1136 for (; num_sources; src_id++, num_sources--) {
> 5b352c5379300ec Cristian Marussi 2020-06-19 1137 sid = &r_evt->sources[src_id];
> 5b352c5379300ec Cristian Marussi 2020-06-19 1138 if (refcount_dec_and_test(sid))
> 5b352c5379300ec Cristian Marussi 2020-06-19 1139 REVT_NOTIFY_DISABLE(r_evt,
> 5b352c5379300ec Cristian Marussi 2020-06-19 1140 r_evt->evt->id, src_id);
> 5b352c5379300ec Cristian Marussi 2020-06-19 1141 }
> 5b352c5379300ec Cristian Marussi 2020-06-19 1142 ret = 1;
> 5b352c5379300ec Cristian Marussi 2020-06-19 1143 }
> 5b352c5379300ec Cristian Marussi 2020-06-19 1144 mutex_unlock(&r_evt->sources_mtx);
> 5b352c5379300ec Cristian Marussi 2020-06-19 1145
> 5b352c5379300ec Cristian Marussi 2020-06-19 1146 return ret;
> 5b352c5379300ec Cristian Marussi 2020-06-19 1147 }
> 5b352c5379300ec Cristian Marussi 2020-06-19 1148
>
> ---
> 0-DAY CI Kernel Test Service, Intel Corporation
> https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx