Dear RT Folks, I'm pleased to announce the 4.4.47-rt59 stable release.
You can get this release via the git tree at: git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-stable-rt.git branch: v4.4-rt Head SHA1: 80398f6fc8e4725cd888477650b5f8a4d441b772 Or to build 4.4.47-rt59 directly, the following patches should be applied: http://www.kernel.org/pub/linux/kernel/v4.x/linux-4.4.tar.xz http://www.kernel.org/pub/linux/kernel/v4.x/patch-4.4.47.xz http://www.kernel.org/pub/linux/kernel/projects/rt/4.4/patch-4.4.47-rt59.patch.xz You can also build from 4.4.47-rt58 by applying the incremental patch: http://www.kernel.org/pub/linux/kernel/projects/rt/4.4/incr/patch-4.4.47-rt58-rt59.patch.xz Enjoy, -- Steve Changes from v4.4.47-rt58: --- Sebastian Andrzej Siewior (2): net: free the sbs in skbufhead workqueue: use rcu_readlock() in put_pwq_unlocked() Steven Rostedt (1): net: Have __napi_schedule_irqoff() disable interrupts on RT Steven Rostedt (VMware) (1): Linux 4.4.47-rt59 Yang Shi (1): arm: kprobe: replace patch_lock to raw lock ---- arch/arm/kernel/patch.c | 6 +++--- include/linux/netdevice.h | 12 ++++++++++++ kernel/workqueue.c | 2 ++ localversion-rt | 2 +- net/core/dev.c | 10 ++++++++++ 5 files changed, 28 insertions(+), 4 deletions(-) --------------------------- diff --git a/arch/arm/kernel/patch.c b/arch/arm/kernel/patch.c index 69bda1a5707e..1f665acaa6a9 100644 --- a/arch/arm/kernel/patch.c +++ b/arch/arm/kernel/patch.c @@ -15,7 +15,7 @@ struct patch { unsigned int insn; }; -static DEFINE_SPINLOCK(patch_lock); +static DEFINE_RAW_SPINLOCK(patch_lock); static void __kprobes *patch_map(void *addr, int fixmap, unsigned long *flags) __acquires(&patch_lock) @@ -32,7 +32,7 @@ static void __kprobes *patch_map(void *addr, int fixmap, unsigned long *flags) return addr; if (flags) - spin_lock_irqsave(&patch_lock, *flags); + raw_spin_lock_irqsave(&patch_lock, *flags); else __acquire(&patch_lock); @@ -47,7 +47,7 @@ static void __kprobes patch_unmap(int fixmap, unsigned long *flags) clear_fixmap(fixmap); if (flags) - spin_unlock_irqrestore(&patch_lock, *flags); + raw_spin_unlock_irqrestore(&patch_lock, *flags); else __release(&patch_lock); } diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 0590f5380814..b3fa55658bd2 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -390,7 +390,19 @@ typedef enum rx_handler_result rx_handler_result_t; typedef rx_handler_result_t rx_handler_func_t(struct sk_buff **pskb); void __napi_schedule(struct napi_struct *n); + +/* + * When PREEMPT_RT_FULL is defined, all device interrupt handlers + * run as threads, and they can also be preempted (without PREEMPT_RT + * interrupt threads can not be preempted). Which means that calling + * __napi_schedule_irqoff() from an interrupt handler can be preempted + * and can corrupt the napi->poll_list. + */ +#ifdef CONFIG_PREEMPT_RT_FULL +#define __napi_schedule_irqoff(n) __napi_schedule(n) +#else void __napi_schedule_irqoff(struct napi_struct *n); +#endif static inline bool napi_disable_pending(struct napi_struct *n) { diff --git a/kernel/workqueue.c b/kernel/workqueue.c index 965d5f65e847..d5b0f4fc0eb0 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -1135,9 +1135,11 @@ static void put_pwq_unlocked(struct pool_workqueue *pwq) * As both pwqs and pools are RCU protected, the * following lock operations are safe. */ + rcu_read_lock(); local_spin_lock_irq(pendingb_lock, &pwq->pool->lock); put_pwq(pwq); local_spin_unlock_irq(pendingb_lock, &pwq->pool->lock); + rcu_read_unlock(); } } diff --git a/localversion-rt b/localversion-rt index f9df2cf089cf..8cdeb45db6e2 100644 --- a/localversion-rt +++ b/localversion-rt @@ -1 +1 @@ --rt58 +-rt59 diff --git a/net/core/dev.c b/net/core/dev.c index a48dbd37dd43..d63b1f9ca08f 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -4714,6 +4714,7 @@ void __napi_schedule(struct napi_struct *n) } EXPORT_SYMBOL(__napi_schedule); +#ifndef CONFIG_PREEMPT_RT_FULL /** * __napi_schedule_irqoff - schedule for receive * @n: entry to schedule @@ -4725,6 +4726,7 @@ void __napi_schedule_irqoff(struct napi_struct *n) ____napi_schedule(this_cpu_ptr(&softnet_data), n); } EXPORT_SYMBOL(__napi_schedule_irqoff); +#endif void __napi_complete(struct napi_struct *n) { @@ -4951,13 +4953,21 @@ static void net_rx_action(struct softirq_action *h) struct softnet_data *sd = this_cpu_ptr(&softnet_data); unsigned long time_limit = jiffies + 2; int budget = netdev_budget; + struct sk_buff_head tofree_q; + struct sk_buff *skb; LIST_HEAD(list); LIST_HEAD(repoll); + __skb_queue_head_init(&tofree_q); + local_irq_disable(); + skb_queue_splice_init(&sd->tofree_queue, &tofree_q); list_splice_init(&sd->poll_list, &list); local_irq_enable(); + while ((skb = __skb_dequeue(&tofree_q))) + kfree_skb(skb); + for (;;) { struct napi_struct *n;
