Re: [ANNOUNCE] v5.2.21-rt14

From: Bernhard Landauer
Date: Wed Dec 04 2019 - 06:55:05 EST


Sorry if maybe I have missed any announcements here, but my I ask if you
are planning on releasing patches for kernels >5,2 in the near future?
Or is this project being faded out altogether?

kind regards
Bernhard

On 04.12.19 10:51, Sebastian Andrzej Siewior wrote:
> Dear RT folks!
>
> I'm pleased to announce the v5.2.21-rt14 patch set.
>
> Changes since v5.2.21-rt13:
>
> - printk. The "emergency loglevel" was used to determine which
> messages are printed directly on the console (if atomic write is
> available (8250 only right now)). By default messages with the log
> level KERN_WARNING (and less) were printed directly.
> As part of the current printk rework it has been decided that only
> messages which lead to system failure like BUG(), panic() should use
> the direct interface. Patch by John Ogness.
>
> - Cherry pick a X86-FPU patch from upstream to avoid a miss
> compilation with gcc-9.
>
> - Make the spin_lock() section also part of a rcu read section on RT.
>
> - PowerPC on 32bit did not compile due to a missing function since the
> softirq rework. It also did not boot due to a bug in the
> lazy-preempt code. It compiles and it has been verified in qemu on a
> book-E target (due to lack of real hardware) that it boots again.
>
> - RT did not compile if CONFIG_HOTPLUG_CPU was not defined. Reported
> by Dick Hollenbeck.
>
> Known issues
> - None
>
> The delta patch against v5.2.21-rt13 is appended below and can be found here:
>
> https://cdn.kernel.org/pub/linux/kernel/projects/rt/5.2/incr/patch-5.2.21-rt13-rt14.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-rt14
>
> 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-rt14.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-rt14.tar.xz
>
> Sebastian
>
> diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
> index d37b373104502..004944258387b 100644
> --- a/arch/powerpc/kernel/entry_32.S
> +++ b/arch/powerpc/kernel/entry_32.S
> @@ -893,10 +893,10 @@ user_exc_return: /* r10 contains MSR_KERNEL here */
> bne restore_kuap
> andi. r8,r8,_TIF_NEED_RESCHED
> bne+ 1f
> - lwz r0,TI_PREEMPT_LAZY(r9)
> + lwz r0,TI_PREEMPT_LAZY(r2)
> cmpwi 0,r0,0 /* if non-zero, just restore regs and return */
> bne restore_kuap
> - lwz r0,TI_FLAGS(r9)
> + lwz r0,TI_FLAGS(r2)
> andi. r0,r0,_TIF_NEED_RESCHED_LAZY
> beq+ restore_kuap
> 1:
> diff --git a/arch/x86/include/asm/fpu/internal.h b/arch/x86/include/asm/fpu/internal.h
> index 4c95c365058aa..44c48e34d7994 100644
> --- a/arch/x86/include/asm/fpu/internal.h
> +++ b/arch/x86/include/asm/fpu/internal.h
> @@ -509,7 +509,7 @@ static inline void __fpu_invalidate_fpregs_state(struct fpu *fpu)
>
> static inline int fpregs_state_valid(struct fpu *fpu, unsigned int cpu)
> {
> - return fpu == this_cpu_read_stable(fpu_fpregs_owner_ctx) && cpu == fpu->last_cpu;
> + return fpu == this_cpu_read(fpu_fpregs_owner_ctx) && cpu == fpu->last_cpu;
> }
>
> /*
> diff --git a/include/linux/preempt.h b/include/linux/preempt.h
> index d559e3a0379c2..7653dd58b4b21 100644
> --- a/include/linux/preempt.h
> +++ b/include/linux/preempt.h
> @@ -100,9 +100,9 @@
> (NMI_MASK | HARDIRQ_MASK | SOFTIRQ_OFFSET)))
> #ifdef CONFIG_PREEMPT_RT_FULL
>
> -#define softirq_count() ((long)get_current()->softirq_count)
> +#define softirq_count() (current->softirq_count)
> #define in_softirq() (softirq_count())
> -#define in_serving_softirq() (get_current()->softirq_count & SOFTIRQ_OFFSET)
> +#define in_serving_softirq() (current->softirq_count & SOFTIRQ_OFFSET)
>
> #else
>
> diff --git a/kernel/cpu.c b/kernel/cpu.c
> index e1bf3c698a321..5bfd13a5cc49d 100644
> --- a/kernel/cpu.c
> +++ b/kernel/cpu.c
> @@ -877,7 +877,9 @@ static int take_cpu_down(void *_param)
> return 0;
> }
>
> +#ifdef CONFIG_PREEMPT_RT_BASE
> struct task_struct *takedown_cpu_task;
> +#endif
>
> static int takedown_cpu(unsigned int cpu)
> {
> diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c
> index bb5c09c49c504..ba4b151bf4517 100644
> --- a/kernel/locking/rtmutex.c
> +++ b/kernel/locking/rtmutex.c
> @@ -1143,6 +1143,7 @@ void __sched rt_spin_lock_slowunlock(struct rt_mutex *lock)
> void __lockfunc rt_spin_lock(spinlock_t *lock)
> {
> sleeping_lock_inc();
> + rcu_read_lock();
> migrate_disable();
> spin_acquire(&lock->dep_map, 0, 0, _RET_IP_);
> rt_spin_lock_fastlock(&lock->lock, rt_spin_lock_slowlock);
> @@ -1158,6 +1159,7 @@ void __lockfunc __rt_spin_lock(struct rt_mutex *lock)
> void __lockfunc rt_spin_lock_nested(spinlock_t *lock, int subclass)
> {
> sleeping_lock_inc();
> + rcu_read_lock();
> migrate_disable();
> spin_acquire(&lock->dep_map, subclass, 0, _RET_IP_);
> rt_spin_lock_fastlock(&lock->lock, rt_spin_lock_slowlock);
> @@ -1171,6 +1173,7 @@ void __lockfunc rt_spin_unlock(spinlock_t *lock)
> spin_release(&lock->dep_map, 1, _RET_IP_);
> rt_spin_lock_fastunlock(&lock->lock, rt_spin_lock_slowunlock);
> migrate_enable();
> + rcu_read_unlock();
> sleeping_lock_dec();
> }
> EXPORT_SYMBOL(rt_spin_unlock);
> @@ -1202,6 +1205,7 @@ int __lockfunc rt_spin_trylock(spinlock_t *lock)
> ret = __rt_mutex_trylock(&lock->lock);
> if (ret) {
> spin_acquire(&lock->dep_map, 0, 1, _RET_IP_);
> + rcu_read_lock();
> } else {
> migrate_enable();
> sleeping_lock_dec();
> @@ -1218,6 +1222,7 @@ int __lockfunc rt_spin_trylock_bh(spinlock_t *lock)
> ret = __rt_mutex_trylock(&lock->lock);
> if (ret) {
> sleeping_lock_inc();
> + rcu_read_lock();
> migrate_disable();
> spin_acquire(&lock->dep_map, 0, 1, _RET_IP_);
> } else
> @@ -1234,6 +1239,7 @@ int __lockfunc rt_spin_trylock_irqsave(spinlock_t *lock, unsigned long *flags)
> ret = __rt_mutex_trylock(&lock->lock);
> if (ret) {
> sleeping_lock_inc();
> + rcu_read_lock();
> migrate_disable();
> spin_acquire(&lock->dep_map, 0, 1, _RET_IP_);
> }
> diff --git a/kernel/locking/rwlock-rt.c b/kernel/locking/rwlock-rt.c
> index c3b91205161cc..0ae8c62ea8320 100644
> --- a/kernel/locking/rwlock-rt.c
> +++ b/kernel/locking/rwlock-rt.c
> @@ -310,6 +310,7 @@ int __lockfunc rt_read_trylock(rwlock_t *rwlock)
> ret = do_read_rt_trylock(rwlock);
> if (ret) {
> rwlock_acquire_read(&rwlock->dep_map, 0, 1, _RET_IP_);
> + rcu_read_lock();
> } else {
> migrate_enable();
> sleeping_lock_dec();
> @@ -327,6 +328,7 @@ int __lockfunc rt_write_trylock(rwlock_t *rwlock)
> ret = do_write_rt_trylock(rwlock);
> if (ret) {
> rwlock_acquire(&rwlock->dep_map, 0, 1, _RET_IP_);
> + rcu_read_lock();
> } else {
> migrate_enable();
> sleeping_lock_dec();
> @@ -338,6 +340,7 @@ EXPORT_SYMBOL(rt_write_trylock);
> void __lockfunc rt_read_lock(rwlock_t *rwlock)
> {
> sleeping_lock_inc();
> + rcu_read_lock();
> migrate_disable();
> rwlock_acquire_read(&rwlock->dep_map, 0, 0, _RET_IP_);
> do_read_rt_lock(rwlock);
> @@ -347,6 +350,7 @@ EXPORT_SYMBOL(rt_read_lock);
> void __lockfunc rt_write_lock(rwlock_t *rwlock)
> {
> sleeping_lock_inc();
> + rcu_read_lock();
> migrate_disable();
> rwlock_acquire(&rwlock->dep_map, 0, 0, _RET_IP_);
> do_write_rt_lock(rwlock);
> @@ -358,6 +362,7 @@ void __lockfunc rt_read_unlock(rwlock_t *rwlock)
> rwlock_release(&rwlock->dep_map, 1, _RET_IP_);
> do_read_rt_unlock(rwlock);
> migrate_enable();
> + rcu_read_unlock();
> sleeping_lock_dec();
> }
> EXPORT_SYMBOL(rt_read_unlock);
> @@ -367,6 +372,7 @@ void __lockfunc rt_write_unlock(rwlock_t *rwlock)
> rwlock_release(&rwlock->dep_map, 1, _RET_IP_);
> do_write_rt_unlock(rwlock);
> migrate_enable();
> + rcu_read_unlock();
> sleeping_lock_dec();
> }
> EXPORT_SYMBOL(rt_write_unlock);
> diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
> index 9d9523431178b..2b4616fd4fd4b 100644
> --- a/kernel/printk/printk.c
> +++ b/kernel/printk/printk.c
> @@ -1767,15 +1767,8 @@ static void call_console_drivers(u64 seq, const char *ext_text, size_t ext_len,
> con->wrote_history = 1;
> con->printk_seq = seq - 1;
> }
> - if (con->write_atomic && level < emergency_console_loglevel &&
> - facility == 0) {
> - /* skip emergency messages, already printed */
> - if (con->printk_seq < seq)
> - con->printk_seq = seq;
> - continue;
> - }
> if (con->flags & CON_BOOT && facility == 0) {
> - /* skip emergency messages, already printed */
> + /* skip boot messages, already printed */
> if (con->printk_seq < seq)
> con->printk_seq = seq;
> continue;
> @@ -3161,7 +3154,7 @@ static bool console_can_emergency(int level)
> for_each_console(con) {
> if (!(con->flags & CON_ENABLED))
> continue;
> - if (con->write_atomic && level < emergency_console_loglevel)
> + if (con->write_atomic && oops_in_progress)
> return true;
> if (con->write && (con->flags & CON_BOOT))
> return true;
> @@ -3177,7 +3170,7 @@ static void call_emergency_console_drivers(int level, const char *text,
> for_each_console(con) {
> if (!(con->flags & CON_ENABLED))
> continue;
> - if (con->write_atomic && level < emergency_console_loglevel) {
> + if (con->write_atomic && oops_in_progress) {
> con->write_atomic(con, text, text_len);
> continue;
> }
> diff --git a/kernel/sched/core.c b/kernel/sched/core.c
> index 6383ade320f23..ef9621815f37e 100644
> --- a/kernel/sched/core.c
> +++ b/kernel/sched/core.c
> @@ -7384,9 +7384,11 @@ void migrate_enable(void)
>
> p->migrate_disable = 0;
> rq->nr_pinned--;
> +#ifdef CONFIG_HOTPLUG_CPU
> if (rq->nr_pinned == 0 && unlikely(!cpu_active(cpu)) &&
> takedown_cpu_task)
> wake_up_process(takedown_cpu_task);
> +#endif
>
> if (!p->migrate_disable_scheduled)
> goto out;
> diff --git a/localversion-rt b/localversion-rt
> index 9f7d0bdbffb18..08b3e75841adc 100644
> --- a/localversion-rt
> +++ b/localversion-rt
> @@ -1 +1 @@
> --rt13
> +-rt14