Hi Michael,
Commit e432fe97f3e5 ("powerpc/bug: Cast to unsigned long before passing
to inline asm") breaks WARN_ON() for 32 bit systems.
arch/powerpc/include/asm/bug.h
109 #define WARN_ON(x) ({ \
110 bool __ret_warn_on = false; \
111 do { \
112 if (__builtin_constant_p((x))) { \
113 if (!(x)) \
114 break; \
115 __WARN(); \
116 __ret_warn_on = true; \
117 } else { \
118 __label__ __label_warn_on; \
119 \
120 WARN_ENTRY(PPC_TLNEI " %4, 0", \
121 BUGFLAG_WARNING |
BUGFLAG_TAINT(TAINT_WARN), \
122 __label_warn_on, \
123 "r" ((__force long)(x))); \
^^^^
If the code is "if (WARN_ON(some_u64)) {" then the cast to long will
truncate away the high bits so it's wrong. (Or at least that's how it
works on x86, I'm working on a work around for Smatch to be able to
parse this WARN_ON(). I don't know anything about PowerPC.)
124 break; \
125 __label_warn_on: \
126 __ret_warn_on = true; \
127 } \
128 } while (0); \
129 unlikely(__ret_warn_on); \
130 })
regards,
dan carpenter
