Merge 4.4.114 into android-4.4

Changes in 4.4.114
	x86/asm/32: Make sync_core() handle missing CPUID on all 32-bit kernels
	usbip: prevent vhci_hcd driver from leaking a socket pointer address
	usbip: Fix implicit fallthrough warning
	usbip: Fix potential format overflow in userspace tools
	x86/microcode/intel: Fix BDW late-loading revision check
	x86/cpu/intel: Introduce macros for Intel family numbers
	x86/retpoline: Fill RSB on context switch for affected CPUs
	sched/deadline: Use the revised wakeup rule for suspending constrained dl tasks
	can: af_can: can_rcv(): replace WARN_ONCE by pr_warn_once
	can: af_can: canfd_rcv(): replace WARN_ONCE by pr_warn_once
	PM / sleep: declare __tracedata symbols as char[] rather than char
	time: Avoid undefined behaviour in ktime_add_safe()
	timers: Plug locking race vs. timer migration
	Prevent timer value 0 for MWAITX
	drivers: base: cacheinfo: fix x86 with CONFIG_OF enabled
	drivers: base: cacheinfo: fix boot error message when acpi is enabled
	PCI: layerscape: Add "fsl,ls2085a-pcie" compatible ID
	PCI: layerscape: Fix MSG TLP drop setting
	mmc: sdhci-of-esdhc: add/remove some quirks according to vendor version
	fs/select: add vmalloc fallback for select(2)
	mm/mmap.c: do not blow on PROT_NONE MAP_FIXED holes in the stack
	hwpoison, memcg: forcibly uncharge LRU pages
	cma: fix calculation of aligned offset
	mm, page_alloc: fix potential false positive in __zone_watermark_ok
	ipc: msg, make msgrcv work with LONG_MIN
	x86/ioapic: Fix incorrect pointers in ioapic_setup_resources()
	ACPI / processor: Avoid reserving IO regions too early
	ACPI / scan: Prefer devices without _HID/_CID for _ADR matching
	ACPICA: Namespace: fix operand cache leak
	netfilter: x_tables: speed up jump target validation
	netfilter: arp_tables: fix invoking 32bit "iptable -P INPUT ACCEPT" failed in 64bit kernel
	netfilter: nf_dup_ipv6: set again FLOWI_FLAG_KNOWN_NH at flowi6_flags
	netfilter: nf_ct_expect: remove the redundant slash when policy name is empty
	netfilter: nfnetlink_queue: reject verdict request from different portid
	netfilter: restart search if moved to other chain
	netfilter: nf_conntrack_sip: extend request line validation
	netfilter: use fwmark_reflect in nf_send_reset
	netfilter: fix IS_ERR_VALUE usage
	netfilter: nfnetlink_cthelper: Add missing permission checks
	netfilter: xt_osf: Add missing permission checks
	ext2: Don't clear SGID when inheriting ACLs
	reiserfs: fix race in prealloc discard
	reiserfs: don't preallocate blocks for extended attributes
	reiserfs: Don't clear SGID when inheriting ACLs
	fs/fcntl: f_setown, avoid undefined behaviour
	scsi: libiscsi: fix shifting of DID_REQUEUE host byte
	Revert "module: Add retpoline tag to VERMAGIC"
	Input: trackpoint - force 3 buttons if 0 button is reported
	usb: usbip: Fix possible deadlocks reported by lockdep
	usbip: fix stub_rx: get_pipe() to validate endpoint number
	usbip: fix stub_rx: harden CMD_SUBMIT path to handle malicious input
	usbip: prevent leaking socket pointer address in messages
	um: link vmlinux with -no-pie
	vsyscall: Fix permissions for emulate mode with KAISER/PTI
	eventpoll.h: add missing epoll event masks
	x86/microcode/intel: Extend BDW late-loading further with LLC size check
	hrtimer: Reset hrtimer cpu base proper on CPU hotplug
	dccp: don't restart ccid2_hc_tx_rto_expire() if sk in closed state
	ipv6: Fix getsockopt() for sockets with default IPV6_AUTOFLOWLABEL
	ipv6: fix udpv6 sendmsg crash caused by too small MTU
	ipv6: ip6_make_skb() needs to clear cork.base.dst
	lan78xx: Fix failure in USB Full Speed
	net: igmp: fix source address check for IGMPv3 reports
	tcp: __tcp_hdrlen() helper
	net: qdisc_pkt_len_init() should be more robust
	pppoe: take ->needed_headroom of lower device into account on xmit
	r8169: fix memory corruption on retrieval of hardware statistics.
	sctp: do not allow the v4 socket to bind a v4mapped v6 address
	sctp: return error if the asoc has been peeled off in sctp_wait_for_sndbuf
	vmxnet3: repair memory leak
	net: Allow neigh contructor functions ability to modify the primary_key
	ipv4: Make neigh lookup keys for loopback/point-to-point devices be INADDR_ANY
	flow_dissector: properly cap thoff field
	net: tcp: close sock if net namespace is exiting
	nfsd: auth: Fix gid sorting when rootsquash enabled
	Linux 4.4.114

Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

4 files changed, 100 insertions, 14 deletions

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 6681abbf2c18..fcb7887dacea 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -2158,6 +2158,7 @@ void __dl_clear_params(struct task_struct *p)
 	dl_se->dl_period = 0;
 	dl_se->flags = 0;
 	dl_se->dl_bw = 0;
+	dl_se->dl_density = 0;
 
 	dl_se->dl_throttled = 0;
 	dl_se->dl_new = 1;
@@ -3767,6 +3768,7 @@ __setparam_dl(struct task_struct *p, const struct sched_attr *attr)
 	dl_se->dl_period = attr->sched_period ?: dl_se->dl_deadline;
 	dl_se->flags = attr->sched_flags;
 	dl_se->dl_bw = to_ratio(dl_se->dl_period, dl_se->dl_runtime);
+	dl_se->dl_density = to_ratio(dl_se->dl_deadline, dl_se->dl_runtime);
 
 	/*
 	 * Changing the parameters of a task is 'tricky' and we're not doing
diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
index 841b393a5e17..5c6ffddcafcd 100644
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -500,13 +500,84 @@ static bool dl_entity_overflow(struct sched_dl_entity *dl_se,
 }
 
 /*
- * When a -deadline entity is queued back on the runqueue, its runtime and
- * deadline might need updating.
+ * Revised wakeup rule [1]: For self-suspending tasks, rather then
+ * re-initializing task's runtime and deadline, the revised wakeup
+ * rule adjusts the task's runtime to avoid the task to overrun its
+ * density.
  *
- * The policy here is that we update the deadline of the entity only if:
- *  - the current deadline is in the past,
- *  - using the remaining runtime with the current deadline would make
- *    the entity exceed its bandwidth.
+ * Reasoning: a task may overrun the density if:
+ *    runtime / (deadline - t) > dl_runtime / dl_deadline
+ *
+ * Therefore, runtime can be adjusted to:
+ *     runtime = (dl_runtime / dl_deadline) * (deadline - t)
+ *
+ * In such way that runtime will be equal to the maximum density
+ * the task can use without breaking any rule.
+ *
+ * [1] Luca Abeni, Giuseppe Lipari, and Juri Lelli. 2015. Constant
+ * bandwidth server revisited. SIGBED Rev. 11, 4 (January 2015), 19-24.
+ */
+static void
+update_dl_revised_wakeup(struct sched_dl_entity *dl_se, struct rq *rq)
+{
+	u64 laxity = dl_se->deadline - rq_clock(rq);
+
+	/*
+	 * If the task has deadline < period, and the deadline is in the past,
+	 * it should already be throttled before this check.
+	 *
+	 * See update_dl_entity() comments for further details.
+	 */
+	WARN_ON(dl_time_before(dl_se->deadline, rq_clock(rq)));
+
+	dl_se->runtime = (dl_se->dl_density * laxity) >> 20;
+}
+
+/*
+ * Regarding the deadline, a task with implicit deadline has a relative
+ * deadline == relative period. A task with constrained deadline has a
+ * relative deadline <= relative period.
+ *
+ * We support constrained deadline tasks. However, there are some restrictions
+ * applied only for tasks which do not have an implicit deadline. See
+ * update_dl_entity() to know more about such restrictions.
+ *
+ * The dl_is_implicit() returns true if the task has an implicit deadline.
+ */
+static inline bool dl_is_implicit(struct sched_dl_entity *dl_se)
+{
+	return dl_se->dl_deadline == dl_se->dl_period;
+}
+
+/*
+ * When a deadline entity is placed in the runqueue, its runtime and deadline
+ * might need to be updated. This is done by a CBS wake up rule. There are two
+ * different rules: 1) the original CBS; and 2) the Revisited CBS.
+ *
+ * When the task is starting a new period, the Original CBS is used. In this
+ * case, the runtime is replenished and a new absolute deadline is set.
+ *
+ * When a task is queued before the begin of the next period, using the
+ * remaining runtime and deadline could make the entity to overflow, see
+ * dl_entity_overflow() to find more about runtime overflow. When such case
+ * is detected, the runtime and deadline need to be updated.
+ *
+ * If the task has an implicit deadline, i.e., deadline == period, the Original
+ * CBS is applied. the runtime is replenished and a new absolute deadline is
+ * set, as in the previous cases.
+ *
+ * However, the Original CBS does not work properly for tasks with
+ * deadline < period, which are said to have a constrained deadline. By
+ * applying the Original CBS, a constrained deadline task would be able to run
+ * runtime/deadline in a period. With deadline < period, the task would
+ * overrun the runtime/period allowed bandwidth, breaking the admission test.
+ *
+ * In order to prevent this misbehave, the Revisited CBS is used for
+ * constrained deadline tasks when a runtime overflow is detected. In the
+ * Revisited CBS, rather than replenishing & setting a new absolute deadline,
+ * the remaining runtime of the task is reduced to avoid runtime overflow.
+ * Please refer to the comments update_dl_revised_wakeup() function to find
+ * more about the Revised CBS rule.
  */
 static void update_dl_entity(struct sched_dl_entity *dl_se,
 			     struct sched_dl_entity *pi_se)
@@ -528,6 +599,14 @@ static void update_dl_entity(struct sched_dl_entity *dl_se,
 
 	if (dl_time_before(dl_se->deadline, rq_clock(rq)) ||
 	    dl_entity_overflow(dl_se, pi_se, rq_clock(rq))) {
+
+		if (unlikely(!dl_is_implicit(dl_se) &&
+			     !dl_time_before(dl_se->deadline, rq_clock(rq)) &&
+			     !dl_se->dl_boosted)){
+			update_dl_revised_wakeup(dl_se, rq);
+			return;
+		}
+
 		dl_se->deadline = rq_clock(rq) + pi_se->dl_deadline;
 		dl_se->runtime = pi_se->dl_runtime;
 	}
@@ -1017,11 +1096,6 @@ static void dequeue_dl_entity(struct sched_dl_entity *dl_se)
 	__dequeue_dl_entity(dl_se);
 }
 
-static inline bool dl_is_constrained(struct sched_dl_entity *dl_se)
-{
-	return dl_se->dl_deadline < dl_se->dl_period;
-}
-
 static void enqueue_task_dl(struct rq *rq, struct task_struct *p, int flags)
 {
 	struct task_struct *pi_task = rt_mutex_get_top_task(p);
@@ -1053,7 +1127,7 @@ static void enqueue_task_dl(struct rq *rq, struct task_struct *p, int flags)
 	 * If that is the case, the task will be throttled and
 	 * the replenishment timer will be set to the next period.
 	 */
-	if (!p->dl.dl_throttled && dl_is_constrained(&p->dl))
+	if (!p->dl.dl_throttled && !dl_is_implicit(&p->dl))
 		dl_check_constrained_dl(&p->dl);
 
 	/*
diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c
index 405536b22c0c..227ea8166a83 100644
--- a/kernel/time/hrtimer.c
+++ b/kernel/time/hrtimer.c
@@ -312,7 +312,7 @@ EXPORT_SYMBOL_GPL(__ktime_divns);
  */
 ktime_t ktime_add_safe(const ktime_t lhs, const ktime_t rhs)
 {
-	ktime_t res = ktime_add(lhs, rhs);
+	ktime_t res = ktime_add_unsafe(lhs, rhs);
 
 	/*
 	 * We use KTIME_SEC_MAX here, the maximum timeout which we can
@@ -669,7 +669,9 @@ static void hrtimer_reprogram(struct hrtimer *timer,
 static inline void hrtimer_init_hres(struct hrtimer_cpu_base *base)
 {
 	base->expires_next.tv64 = KTIME_MAX;
+	base->hang_detected = 0;
 	base->hres_active = 0;
+	base->next_timer = NULL;
 }
 
 /*
@@ -1615,6 +1617,7 @@ static void init_hrtimers_cpu(int cpu)
 		timerqueue_init_head(&cpu_base->clock_base[i].active);
 	}
 
+	cpu_base->active_bases = 0;
 	cpu_base->cpu = cpu;
 	hrtimer_init_hres(cpu_base);
 }
diff --git a/kernel/time/timer.c b/kernel/time/timer.c
index f575785c7cd8..523fe1669d4c 100644
--- a/kernel/time/timer.c
+++ b/kernel/time/timer.c
@@ -764,8 +764,15 @@ static struct tvec_base *lock_timer_base(struct timer_list *timer,
 	__acquires(timer->base->lock)
 {
 	for (;;) {
-		u32 tf = timer->flags;
 		struct tvec_base *base;
+		u32 tf;
+
+		/*
+		 * We need to use READ_ONCE() here, otherwise the compiler
+		 * might re-read @tf between the check for TIMER_MIGRATING
+		 * and spin_lock().
+		 */
+		tf = READ_ONCE(timer->flags);
 
 		if (!(tf & TIMER_MIGRATING)) {
 			base = per_cpu_ptr(&tvec_bases, tf & TIMER_CPUMASK);