[PATCH kcsan 2/3] objtool, kcsan: Add volatile read/write instrumentation to whitelist

From: Paul E. McKenney
Date: Wed Oct 19 2022 - 19:04:21 EST


From: Marco Elver <elver@xxxxxxxxxx>

Adds KCSAN's volatile instrumentation to objtool's uaccess whitelist.

Recent kernel change have shown that this was missing from the uaccess
whitelist (since the first upstreamed version of KCSAN):

mm/gup.o: warning: objtool: fault_in_readable+0x101: call to __tsan_volatile_write1() with UACCESS enabled

Fixes: 75d75b7a4d54 ("kcsan: Support distinguishing volatile accesses")
Signed-off-by: Marco Elver <elver@xxxxxxxxxx>
Reviewed-by: Dmitry Vyukov <dvyukov@xxxxxxxxxx>
Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxx>
---
tools/objtool/check.c | 10 ++++++++++
1 file changed, 10 insertions(+)

diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index 43ec14c29a60c..a7f1e6c8bb0a7 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -999,6 +999,16 @@ static const char *uaccess_safe_builtin[] = {
"__tsan_read_write4",
"__tsan_read_write8",
"__tsan_read_write16",
+ "__tsan_volatile_read1",
+ "__tsan_volatile_read2",
+ "__tsan_volatile_read4",
+ "__tsan_volatile_read8",
+ "__tsan_volatile_read16",
+ "__tsan_volatile_write1",
+ "__tsan_volatile_write2",
+ "__tsan_volatile_write4",
+ "__tsan_volatile_write8",
+ "__tsan_volatile_write16",
"__tsan_atomic8_load",
"__tsan_atomic16_load",
"__tsan_atomic32_load",
--
2.31.1.189.g2e36527f23