When the kernel is built with:
CONFIG_PREEMPT=y
CONFIG_PREEMPT_COUNT=y
"stfle" function used by kasan initialization code makes additional
call to preempt_count_add/preempt_count_sub. To avoid removing kasan
instrumentation from sched code where those functions leave split stfle
function and provide __stfle variant without preemption handling to be
used by Kasan.
Reported-by: Benjamin Block <bblock@linux.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* @stfle_fac_list: array where facility list can be stored
* @size: size of passed in array in double words
*/
-static inline void stfle(u64 *stfle_fac_list, int size)
+static inline void __stfle(u64 *stfle_fac_list, int size)
{
unsigned long nr;
- preempt_disable();
asm volatile(
" stfl 0(0)\n"
: "=m" (S390_lowcore.stfl_fac_list));
nr = (reg0 + 1) * 8; /* # bytes stored by stfle */
}
memset((char *) stfle_fac_list + nr, 0, size * 8 - nr);
+}
+
+static inline void stfle(u64 *stfle_fac_list, int size)
+{
+ preempt_disable();
+ __stfle(stfle_fac_list, size);
preempt_enable();
}
static void __init kasan_early_detect_facilities(void)
{
- stfle(S390_lowcore.stfle_fac_list,
- ARRAY_SIZE(S390_lowcore.stfle_fac_list));
+ __stfle(S390_lowcore.stfle_fac_list,
+ ARRAY_SIZE(S390_lowcore.stfle_fac_list));
if (test_facility(8)) {
has_edat = true;
__ctl_set_bit(0, 23);