Merge branches 'pm-core', 'pm-clk', 'pm-domains' and 'pm-pci'

[deliverable/linux.git] / arch / arm64 / mm / context.c

diff --git a/arch/arm64/mm/context.c b/arch/arm64/mm/context.c
index b7b397802088d1b6c5af50efac9aa49852cbf242..efcf1f7ef1e4c27b4c0c40546dc542122f824933 100644 (file)
--- a/arch/arm64/mm/context.c
+++ b/arch/arm64/mm/context.c
@@ -179,7 +179,7 @@ static u64 new_context(struct mm_struct *mm, unsigned int cpu)
                                                 &asid_generation);
        flush_context(cpu);
 
-       /* We have at least 1 ASID per CPU, so this will always succeed */
+       /* We have more ASIDs than CPUs, so this will always succeed */
        asid = find_next_zero_bit(asid_map, NUM_USER_ASIDS, 1);
 
 set_asid:
@@ -227,8 +227,11 @@ switch_mm_fastpath:
 static int asids_init(void)
 {
        asid_bits = get_cpu_asid_bits();
-       /* If we end up with more CPUs than ASIDs, expect things to crash */
-       WARN_ON(NUM_USER_ASIDS < num_possible_cpus());
+       /*
+        * Expect allocation after rollover to fail if we don't have at least
+        * one more ASID than CPUs. ASID #0 is reserved for init_mm.
+        */
+       WARN_ON(NUM_USER_ASIDS - 1 <= num_possible_cpus());
        atomic64_set(&asid_generation, ASID_FIRST_VERSION);
        asid_map = kzalloc(BITS_TO_LONGS(NUM_USER_ASIDS) * sizeof(*asid_map),
                           GFP_KERNEL);