On Wed, 23 Jul 2025 13:31:52 -0700
Linus Torvalds [off-list ref] wrote:

On Wed, 23 Jul 2025 at 12:42, Steven Rostedt [off-list ref] wrote:

quoted

 kernel/trace/Kconfig              |  19 +++  

Annoying "one step forward, two steps back" change.

You literally sent a "remove one pointless Kconfig option" patch
within ten minutes of sending out this "add two pointless Kconfig
options" patch.

You mean to also get rid of the TRACEPOINT_VERIFY_USED config?

Because as long as it's a build-time thing, please just fix the
problems it points out, and it should have no real cost to being
enabled.

We don't want to ask people questions that don't matter.

Of course, because you *used* to check this at run-time, you put the
new "__tracepoint_check" table in a section that is actually loaded
into memory, and it appears to be still there.

Just put it in the discard section, the same way we have (for example)
the export_symbols table that we also check at build-time without
actually ever making it part of the kernel.

Ah, I wasn't sure how to do that. So you are saying to do:

diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h
index 600d8b51e315..365c92e6d0ce 100644
--- a/include/asm-generic/vmlinux.lds.h
+++ b/include/asm-generic/vmlinux.lds.h

@@ -1048,6 +1047,7 @@ defined(CONFIG_AUTOFDO_CLANG) || defined(CONFIG_PROPELLER_CLANG)
 	*(.modinfo)							\
 	/* ld.bfd warns about .gnu.version* even when not emitted */	\
 	*(.gnu.version*)						\
+	*(.__tracepoint_check)
 
 #define DISCARDS							\
 	/DISCARD/ : {							\

But this will require that I change how it's done, as it doesn't look like
it's available when sorttable.c is used.

Looks like it will require a separate application to search the vmlinux.o
instead of the vmlinux (which sorttable does).

I could probably take some of the sorttable.c elf parsing and move that
into a header that would share the code.

-- Steve