[PATCH v5 05/17] compiler.h: Make __ADDRESSABLE() symbol truly unique

Peter Zijlstra
2020-06-24T15:52:18Z

From: Josh Poimboeuf <jpoimboe@redhat.com>

The __ADDRESSABLE() macro uses the __LINE__ macro to create a temporary
symbol which has a unique name. However, if the macro is used multiple
times from within another macro, the line number will always be the
same, resulting in duplicate symbols.

Make the temporary symbols truly unique by using __UNIQUE_ID instead of
__LINE__.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
---
include/linux/compiler.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/include/linux/compiler.h
+++ b/include/linux/compiler.h
@@ -299,7 +299,7 @@ unsigned long read_word_at_a_time(const
*/
#define __ADDRESSABLE(sym) \
static void * __section(.discard.addressable) __used \
- __PASTE(__addressable_##sym, __LINE__) = (void *)&sym;
+ __UNIQUE_ID(__PASTE(__addressable_,sym)) = (void *)&sym;

/**
* offset_to_ptr - convert a relative memory offset to an absolute pointer