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| author | Dave Airlie <airlied@redhat.com> | 2016-07-02 05:56:01 (GMT) |
|---|---|---|
| committer | Dave Airlie <airlied@redhat.com> | 2016-07-02 05:56:01 (GMT) |
| commit | 542d972221e024681b502033154f917c1455469f (patch) | |
| tree | 1c7c1be768f6e1b496a3edad6b105804a8d05c57 /arch/arm64/mm/context.c | |
| parent | 583fa4e02775b26d76771d4e1ddc6f10ba005ef2 (diff) | |
| parent | 4c2e07c6a29e0129e975727b9f57eede813eea85 (diff) | |
| download | linux-542d972221e024681b502033154f917c1455469f.tar.xz | |
Back-merge tag 'v4.7-rc5' into drm-next
Linux 4.7-rc5
The fsl-dcu pull needs -rc3 so go to -rc5 for now.
Diffstat (limited to 'arch/arm64/mm/context.c')
| -rw-r--r-- | arch/arm64/mm/context.c | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/arch/arm64/mm/context.c b/arch/arm64/mm/context.c index b7b3978..efcf1f7 100644 --- 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); |