[PATCH 4/4] objtool: add UACCESS exceptions for __tsan_volatile_read/write

From: Arnd Bergmann
Date: Wed Feb 08 2023 - 11:41:43 EST


From: Arnd Bergmann <arnd@xxxxxxxx>

A lot of the tsan helpers are already excempt from the UACCESS warnings,
but some more functions were added that need the same thing:

kernel/kcsan/core.o: warning: objtool: __tsan_volatile_read16+0x0: call to __tsan_unaligned_read16() with UACCESS enabled
kernel/kcsan/core.o: warning: objtool: __tsan_volatile_write16+0x0: call to __tsan_unaligned_write16() with UACCESS enabled
vmlinux.o: warning: objtool: __tsan_unaligned_volatile_read16+0x4: call to __tsan_unaligned_read16() with UACCESS enabled
vmlinux.o: warning: objtool: __tsan_unaligned_volatile_write16+0x4: call to __tsan_unaligned_write16() with UACCESS enabled

Fixes: 75d75b7a4d54 ("kcsan: Support distinguishing volatile accesses")
Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
---
tools/objtool/check.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index e8fb3bf7a2e3..d89ef6957021 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -1200,6 +1200,8 @@ static const char *uaccess_safe_builtin[] = {
"__tsan_atomic64_compare_exchange_val",
"__tsan_atomic_thread_fence",
"__tsan_atomic_signal_fence",
+ "__tsan_unaligned_read16",
+ "__tsan_unaligned_write16",
/* KCOV */
"write_comp_data",
"check_kcov_mode",
--
2.39.1