s390/pai_crypto: emit error on too many counters

When the device driver is initialized, it checks the number of
possible counters. Should this number be too high, emit an error
and return.

Reported-by: Sumanth Korikkar <sumanthk@linux.ibm.com>
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Acked-by: Sumanth Korikkar <sumanthk@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

diff --git a/arch/s390/kernel/perf_pai_crypto.c b/arch/s390/kernel/perf_pai_crypto.c
index 522a5ea0a9f49c68b52b4426533f23f2c314baa4..69639ff1c5e0326757215b1a2fad52f8480ba819 100644 (file)
--- a/arch/s390/kernel/perf_pai_crypto.c
+++ b/arch/s390/kernel/perf_pai_crypto.c
@@ -742,8 +742,10 @@ static int __init paicrypt_init(void)
        paicrypt_cnt = ib.num_cc;
        if (paicrypt_cnt == 0)
                return 0;
-       if (paicrypt_cnt >= PAI_CRYPTO_MAXCTR)
-               paicrypt_cnt = PAI_CRYPTO_MAXCTR - 1;
+       if (paicrypt_cnt >= PAI_CRYPTO_MAXCTR) {
+               pr_err("Too many PMU pai_crypto counters %d\n", paicrypt_cnt);
+               return -1;
+       }
 
        rc = attr_event_init();         /* Export known PAI crypto events */
        if (rc) {