Dear RT folks! I'm pleased to announce the v5.2.21-rt15 patch set. Changes since v5.2.21-rt14: - Since the migrate_disable() rework, the kernel did not build on UP or without RT enabled. Patch by Daniel Wagner. - Since the migrate_disable() rework, with heave changing of the task's affinity mask the kernel could issue a warning in migrate_enable() and crash later. Known issues - None The delta patch against v5.2.21-rt14 is appended below and can be found here: https://cdn.kernel.org/pub/linux/kernel/projects/rt/5.2/incr/patch-5.2.21-rt14-rt15.patch.xz You can get this release via the git tree at: git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git v5.2.21-rt15 The RT patch against v5.2.21 can be found here: https://cdn.kernel.org/pub/linux/kernel/projects/rt/5.2/older/patch-5.2.21-rt15.patch.xz The split quilt queue is available at: https://cdn.kernel.org/pub/linux/kernel/projects/rt/5.2/older/patches-5.2.21-rt15.tar.xz Sebastian diff --git a/kernel/sched/core.c b/kernel/sched/core.c index ef9621815f37e..ab04f5c48787d 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -7399,7 +7399,7 @@ void migrate_enable(void) WARN_ON(smp_processor_id() != cpu); if (!is_cpu_allowed(p, cpu)) { - struct migration_arg arg = { p }; + struct migration_arg arg = { .task = p }; struct cpu_stop_work work; struct rq_flags rf; @@ -7411,7 +7411,10 @@ void migrate_enable(void) stop_one_cpu_nowait(task_cpu(p), migration_cpu_stop, &arg, &work); __schedule(true); - WARN_ON_ONCE(!arg.done && !work.disabled); + if (!work.disabled) { + while (!arg.done) + cpu_relax(); + } } out: diff --git a/lib/smp_processor_id.c b/lib/smp_processor_id.c index 5f2618d346c42..c2f5b0f8cacd0 100644 --- a/lib/smp_processor_id.c +++ b/lib/smp_processor_id.c @@ -23,8 +23,10 @@ unsigned int check_preemption_disabled(const char *what1, const char *what2) * Kernel threads bound to a single CPU can safely use * smp_processor_id(): */ +#if defined(CONFIG_PREEMPT_RT_BASE) && (defined(CONFIG_SMP) || defined(CONFIG_SCHED_DEBUG)) if (current->migrate_disable) goto out; +#endif if (current->nr_cpus_allowed == 1) goto out; diff --git a/localversion-rt b/localversion-rt index 08b3e75841adc..18777ec0c27d4 100644 --- a/localversion-rt +++ b/localversion-rt @@ -1 +1 @@ --rt14 +-rt15