On Wed, 18 Dec 2019 22:58:23 -0500
Qian Cai <c...@lca.pw> wrote:
> The linux-next commit "ftrace: Rework event_create_dir()” [1] triggers boot
> warnings
> for Clang-build (Clang version 8.0.1) kernels (reproduced on both arm64 and
> powerpc).
> Reverted it (with trivial conflict fixes) on the top of today’s linux-next
> fixed the issue.
>
> configs:
> https://raw.githubusercontent.com/cailca/linux-mm/master/arm64.config
> https://raw.githubusercontent.com/cailca/linux-mm/master/powerpc.config
>
> [1] https://lore.kernel.org/lkml/20191111132458.342979...@infradead.org/
>
> [ 115.799327][ T1] Registered efivars operations
> [ 115.849770][ T1] clocksource: Switched to clocksource arch_sys_counter
> [ 115.901145][ T1] Could not initialize trace point
> events/sys_enter_rt_sigreturn
> [ 115.908854][ T1] Could not create directory for event
> sys_enter_rt_sigreturn
> [ 115.998949][ T1] Could not initialize trace point
> events/sys_enter_restart_syscall
> [ 116.006802][ T1] Could not create directory for event
> sys_enter_restart_syscall
> [ 116.062702][ T1] Could not initialize trace point
> events/sys_enter_getpid
> [ 116.069828][ T1] Could not create directory for event sys_enter_getpid
> [ 116.078058][ T1] Could not initialize trace point
> events/sys_enter_gettid
> [ 116.085181][ T1] Could not create directory for event sys_enter_gettid
> [ 116.093405][ T1] Could not initialize trace point
> events/sys_enter_getppid
> [ 116.100612][ T1] Could not create directory for event sys_enter_getppid
> [ 116.108989][ T1] Could not initialize trace point
> events/sys_enter_getuid
> [ 116.116058][ T1] Could not create directory for event sys_enter_getuid
> [ 116.124250][ T1] Could not initialize trace point
> events/sys_enter_geteuid
> [ 116.131457][ T1] Could not create directory for event sys_enter_geteuid
> [ 116.139840][ T1] Could not initialize trace point
> events/sys_enter_getgid
> [ 116.146908][ T1] Could not create directory for event sys_enter_getgid
> [ 116.155163][ T1] Could not initialize trace point
> events/sys_enter_getegid
> [ 116.162370][ T1] Could not create directory for event sys_enter_getegid
> [ 116.178015][ T1] Could not initialize trace point
> events/sys_enter_setsid
> [ 116.185138][ T1] Could not create directory for event sys_enter_setsid
> [ 116.269307][ T1] Could not initialize trace point
> events/sys_enter_sched_yield
> [ 116.276811][ T1] Could not create directory for event
> sys_enter_sched_yield
> [ 116.527652][ T1] Could not initialize trace point
> events/sys_enter_munlockall
> [ 116.535126][ T1] Could not create directory for event
> sys_enter_munlockall
> [ 116.622096][ T1] Could not initialize trace point
> events/sys_enter_vhangup
> [ 116.629307][ T1] Could not create directory for event sys_enter_vhangup
> [ 116.783867][ T1] Could not initialize trace point events/sys_enter_sync
> [ 116.790819][ T1] Could not create directory for event sys_enter_sync
> [ 117.723402][ T1] pnp: PnP ACPI init
I noticed that all of the above have zero parameters. Does the
following patch fix it?
(note, I prefer "ret" and "i" on different lines anyway)
-- Steve
diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c
index 53935259f701..abb70c71fe60 100644
--- a/kernel/trace/trace_syscalls.c
+++ b/kernel/trace/trace_syscalls.c
@@ -269,7 +269,8 @@ static int __init syscall_enter_define_fields(struct
trace_event_call *call)
struct syscall_trace_enter trace;
struct syscall_metadata *meta = call->data;
int offset = offsetof(typeof(trace), args);
- int ret, i;
+ int ret = 0;
+ int i;
for (i = 0; i < meta->nb_args; i++) {
ret = trace_define_field(call, meta->types[i],
