Re: [PATCH] checkpatch: add warning for avoiding .L prefix symbols in assembly files

From: Joe Perches
Date: Fri Jan 22 2021 - 14:12:26 EST


On Fri, 2021-01-22 at 18:48 +0530, Aditya wrote:
> On 21/1/21 12:13 am, Joe Perches wrote:
> > I believe the test should be:
> >
> > if ($realfile =~ /\.S$/ &&
> > $line =~ /^\+\s*SYM_[A-Z]+_(?:START|END)(?:_[A-Z_]+)?\s*\(\s*\.L/) {
>
> Joe, with this regex, we won't be able to match
> "jmp .L_restore
> SYM_FUNC_END(\name)"

I think that's not an issue.

> which was replaced in this patch in the discussion:
> https://groups.google.com/g/clang-built-linux/c/-drkmLgu-cU/m/phKe-Tb6CgAJ
>
> Here, "jmp .L_restore" was also replaced to fix the error.

Notice that this line was also replaced in the same patch:

#ifdef CONFIG_PREEMPTION
-SYM_CODE_START_LOCAL_NOALIGN(.L_restore)
+SYM_CODE_START_LOCAL_NOALIGN(__thunk_restore)


> However, if this
> regex(/^\+\s*SYM_[A-Z]+_(?:START|END)(?:_[A-Z_]+)?\s*\(\s*\.L/) is
> correct, maybe we don't need to check for $file as we are now checking
> for just one line.
>
> What do you think?

The test I wrote was complete, did not use $file and emits a
warning on the use of CODE_SYM_START_LOCAL_NOALIGN(.L_restore)

I think it's sufficient.