Re: [PATCHv5 bpf-next 1/5] kallsyms: Fully export kallsyms_on_each_symbol function

From: Jiri Olsa
Date: Mon May 09 2022 - 03:51:37 EST


On Mon, May 09, 2022 at 08:01:04AM +0200, Christoph Hellwig wrote:
> I'm not sure how I'm supposed to review just a patch 1 out of 5
> without the rest.

sorry, I did not think the rest was needed, full patchset is in here:
https://lore.kernel.org/bpf/20220507125711.2022238-1-jolsa@xxxxxxxxxx/

I'll cc you on full patchset in next version

>
> What I can ѕay without the rest is that the subject line is wrong
> as nothing is exported, and that you are adding an overly long line.

right, how about the change below?

thanks,
jirka


---
Subject: [PATCH] kallsyms: Make kallsyms_on_each_symbol generally available

Making kallsyms_on_each_symbol generally available, so it can be
used outside CONFIG_LIVEPATCH option in following changes.

Rather than adding another ifdef option let's make the function
generally available (when CONFIG_KALLSYMS option is defined).

Cc: Christoph Hellwig <hch@xxxxxx>
Reviewed-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
---
include/linux/kallsyms.h | 7 ++++++-
kernel/kallsyms.c | 2 --
2 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/include/linux/kallsyms.h b/include/linux/kallsyms.h
index ce1bd2fbf23e..ad39636e0c3f 100644
--- a/include/linux/kallsyms.h
+++ b/include/linux/kallsyms.h
@@ -65,11 +65,11 @@ static inline void *dereference_symbol_descriptor(void *ptr)
return ptr;
}

+#ifdef CONFIG_KALLSYMS
int kallsyms_on_each_symbol(int (*fn)(void *, const char *, struct module *,
unsigned long),
void *data);

-#ifdef CONFIG_KALLSYMS
/* Lookup the address for a symbol. Returns 0 if not found. */
unsigned long kallsyms_lookup_name(const char *name);

@@ -163,6 +163,11 @@ static inline bool kallsyms_show_value(const struct cred *cred)
return false;
}

+static inline int kallsyms_on_each_symbol(int (*fn)(void *, const char *, struct module *,
+ unsigned long), void *data)
+{
+ return -EOPNOTSUPP;
+}
#endif /*CONFIG_KALLSYMS*/

static inline void print_ip_sym(const char *loglvl, unsigned long ip)
diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c
index 79f2eb617a62..fdfd308bebc4 100644
--- a/kernel/kallsyms.c
+++ b/kernel/kallsyms.c
@@ -228,7 +228,6 @@ unsigned long kallsyms_lookup_name(const char *name)
return module_kallsyms_lookup_name(name);
}

-#ifdef CONFIG_LIVEPATCH
/*
* Iterate over all symbols in vmlinux. For symbols from modules use
* module_kallsyms_on_each_symbol instead.
@@ -251,7 +250,6 @@ int kallsyms_on_each_symbol(int (*fn)(void *, const char *, struct module *,
}
return 0;
}
-#endif /* CONFIG_LIVEPATCH */

static unsigned long get_symbol_pos(unsigned long addr,
unsigned long *symbolsize,
--
2.35.3