Re: [PATCH v2] tracing: kmem: convert call_site addresses to user friendly symbols

From: Steven Rostedt
Date: Wed Jul 24 2019 - 16:12:26 EST



Hmm, get_maintainers.pl fails to get the people I think should be
maintaining include/trace/events/kmem.h.

On Mon, 22 Jul 2019 17:42:59 -0400
"George G. Davis" <george_davis@xxxxxxxxxx> wrote:

> While attempting to debug slub freelist pointer corruption bugs
> caused by a module, I discovered that the kmem call_site addresses are
> not at all user friendly for modules unless you manage to save a copy
> of kallsyms for the running kernel beforehand.
>
> So convert kmem call_site addresses to user friendly symbols which is
> especially helpful for module callers when you don't have a copy of
> kallsyms for the running kernel.
>
> Reported-by: kbuild test robot <lkp@xxxxxxxxx>
> Signed-off-by: George G. Davis <george_davis@xxxxxxxxxx>

Reviewed-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>

I can take this if nobody else does.

-- Steve


> ---
> Change history:
> v1:
> - First submission
> v2:
> - Fix kbuild test robot issues as suggested by
> Steven Rostedt.
> ---
> include/trace/events/kmem.h | 11 ++++++-----
> 1 file changed, 6 insertions(+), 5 deletions(-)
>
> diff --git a/include/trace/events/kmem.h b/include/trace/events/kmem.h
> index eb57e3037deb..09e1eeb4e44d 100644
> --- a/include/trace/events/kmem.h
> +++ b/include/trace/events/kmem.h
> @@ -35,8 +35,8 @@ DECLARE_EVENT_CLASS(kmem_alloc,
> __entry->gfp_flags = gfp_flags;
> ),
>
> - TP_printk("call_site=%lx ptr=%p bytes_req=%zu bytes_alloc=%zu gfp_flags=%s",
> - __entry->call_site,
> + TP_printk("call_site=%pS ptr=%p bytes_req=%zu bytes_alloc=%zu gfp_flags=%s",
> + (void *)__entry->call_site,
> __entry->ptr,
> __entry->bytes_req,
> __entry->bytes_alloc,
> @@ -88,8 +88,8 @@ DECLARE_EVENT_CLASS(kmem_alloc_node,
> __entry->node = node;
> ),
>
> - TP_printk("call_site=%lx ptr=%p bytes_req=%zu bytes_alloc=%zu gfp_flags=%s node=%d",
> - __entry->call_site,
> + TP_printk("call_site=%pS ptr=%p bytes_req=%zu bytes_alloc=%zu gfp_flags=%s node=%d",
> + (void *)__entry->call_site,
> __entry->ptr,
> __entry->bytes_req,
> __entry->bytes_alloc,
> @@ -131,7 +131,8 @@ DECLARE_EVENT_CLASS(kmem_free,
> __entry->ptr = ptr;
> ),
>
> - TP_printk("call_site=%lx ptr=%p", __entry->call_site, __entry->ptr)
> + TP_printk("call_site=%pS ptr=%p",
> + (void *)__entry->call_site, __entry->ptr)
> );
>
> DEFINE_EVENT(kmem_free, kfree,