diff options
| -rw-r--r-- | arch/arm64/kernel/fpsimd.c | 16 |
1 files changed, 14 insertions, 2 deletions
diff --git a/arch/arm64/kernel/fpsimd.c b/arch/arm64/kernel/fpsimd.c index 6e53badff8a6..a568735b7c2e 100644 --- a/arch/arm64/kernel/fpsimd.c +++ b/arch/arm64/kernel/fpsimd.c @@ -237,10 +237,19 @@ static void __get_cpu_fpsimd_context(void) * * The double-underscore version must only be called if you know the task * can't be preempted. + * + * On RT kernels local_bh_disable() is not sufficient because it only + * serializes soft interrupt related sections via a local lock, but stays + * preemptible. Disabling preemption is the right choice here as bottom + * half processing is always in thread context on RT kernels so it + * implicitly prevents bottom half processing as well. */ static void get_cpu_fpsimd_context(void) { - local_bh_disable(); + if (!IS_ENABLED(CONFIG_PREEMPT_RT)) + local_bh_disable(); + else + preempt_disable(); __get_cpu_fpsimd_context(); } @@ -261,7 +270,10 @@ static void __put_cpu_fpsimd_context(void) static void put_cpu_fpsimd_context(void) { __put_cpu_fpsimd_context(); - local_bh_enable(); + if (!IS_ENABLED(CONFIG_PREEMPT_RT)) + local_bh_enable(); + else + preempt_enable(); } static bool have_cpu_fpsimd_context(void) |