Merge 4.4.109 into android-4.4

Changes in 4.4.109
	ACPI: APEI / ERST: Fix missing error handling in erst_reader()
	crypto: mcryptd - protect the per-CPU queue with a lock
	mfd: cros ec: spi: Don't send first message too soon
	mfd: twl4030-audio: Fix sibling-node lookup
	mfd: twl6040: Fix child-node lookup
	ALSA: rawmidi: Avoid racy info ioctl via ctl device
	ALSA: usb-audio: Fix the missing ctl name suffix at parsing SU
	PCI / PM: Force devices to D0 in pci_pm_thaw_noirq()
	parisc: Hide Diva-built-in serial aux and graphics card
	spi: xilinx: Detect stall with Unknown commands
	KVM: X86: Fix load RFLAGS w/o the fixed bit
	kvm: x86: fix RSM when PCID is non-zero
	powerpc/perf: Dereference BHRB entries safely
	net: mvneta: clear interface link status on port disable
	tracing: Remove extra zeroing out of the ring buffer page
	tracing: Fix possible double free on failure of allocating trace buffer
	tracing: Fix crash when it fails to alloc ring buffer
	ring-buffer: Mask out the info bits when returning buffer page length
	iw_cxgb4: Only validate the MSN for successful completions
	ASoC: fsl_ssi: AC'97 ops need regmap, clock and cleaning up on failure
	ASoC: twl4030: fix child-node lookup
	ALSA: hda: Drop useless WARN_ON()
	ALSA: hda - fix headset mic detection issue on a Dell machine
	x86/vm86/32: Switch to flush_tlb_mm_range() in mark_screen_rdonly()
	x86/mm: Remove flush_tlb() and flush_tlb_current_task()
	x86/mm: Make flush_tlb_mm_range() more predictable
	x86/mm: Reimplement flush_tlb_page() using flush_tlb_mm_range()
	x86/mm: Remove the UP asm/tlbflush.h code, always use the (formerly) SMP code
	x86/mm: Disable PCID on 32-bit kernels
	x86/mm: Add the 'nopcid' boot option to turn off PCID
	x86/mm: Enable CR4.PCIDE on supported systems
	x86/mm/64: Fix reboot interaction with CR4.PCIDE
	kbuild: add '-fno-stack-check' to kernel build options
	ipv4: igmp: guard against silly MTU values
	ipv6: mcast: better catch silly mtu values
	net: igmp: Use correct source address on IGMPv3 reports
	netlink: Add netns check on taps
	net: qmi_wwan: add Sierra EM7565 1199:9091
	net: reevalulate autoflowlabel setting after sysctl setting
	tcp md5sig: Use skb's saddr when replying to an incoming segment
	tg3: Fix rx hang on MTU change with 5717/5719
	net: ipv4: fix for a race condition in raw_sendmsg
	net: mvmdio: disable/unprepare clocks in EPROBE_DEFER case
	sctp: Replace use of sockets_allocated with specified macro.
	ipv4: Fix use-after-free when flushing FIB tables
	net: bridge: fix early call to br_stp_change_bridge_id and plug newlink leaks
	net: Fix double free and memory corruption in get_net_ns_by_id()
	net: phy: micrel: ksz9031: reconfigure autoneg after phy autoneg workaround
	sock: free skb in skb_complete_tx_timestamp on error
	usbip: fix usbip bind writing random string after command in match_busid
	usbip: stub: stop printing kernel pointer addresses in messages
	usbip: vhci: stop printing kernel pointer addresses in messages
	USB: serial: ftdi_sio: add id for Airbus DS P8GR
	USB: serial: qcserial: add Sierra Wireless EM7565
	USB: serial: option: add support for Telit ME910 PID 0x1101
	USB: serial: option: adding support for YUGA CLM920-NC5
	usb: Add device quirk for Logitech HD Pro Webcam C925e
	usb: add RESET_RESUME for ELSA MicroLink 56K
	USB: Fix off by one in type-specific length check of BOS SSP capability
	usb: xhci: Add XHCI_TRUST_TX_LENGTH for Renesas uPD720201
	nohz: Prevent a timer interrupt storm in tick_nohz_stop_sched_tick()
	x86/smpboot: Remove stale TLB flush invocations
	n_tty: fix EXTPROC vs ICANON interaction with TIOCINQ (aka FIONREAD)
	mm/vmstat: Make NR_TLB_REMOTE_FLUSH_RECEIVED available even on UP
	Linux 4.4.109

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

3 files changed, 26 insertions, 12 deletions

diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index 34f9a9c417d9..a935cbdc55a4 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -568,6 +568,11 @@ static void tick_nohz_restart(struct tick_sched *ts, ktime_t now)
 		tick_program_event(hrtimer_get_expires(&ts->sched_timer), 1);
 }
 
+static inline bool local_timer_softirq_pending(void)
+{
+	return local_softirq_pending() & TIMER_SOFTIRQ;
+}
+
 static ktime_t tick_nohz_stop_sched_tick(struct tick_sched *ts,
 					 ktime_t now, int cpu)
 {
@@ -584,8 +589,18 @@ static ktime_t tick_nohz_stop_sched_tick(struct tick_sched *ts,
 	} while (read_seqretry(&jiffies_lock, seq));
 	ts->last_jiffies = basejiff;
 
-	if (rcu_needs_cpu(basemono, &next_rcu) ||
-	    arch_needs_cpu() || irq_work_needs_cpu()) {
+	/*
+	 * Keep the periodic tick, when RCU, architecture or irq_work
+	 * requests it.
+	 * Aside of that check whether the local timer softirq is
+	 * pending. If so its a bad idea to call get_next_timer_interrupt()
+	 * because there is an already expired timer, so it will request
+	 * immeditate expiry, which rearms the hardware timer with a
+	 * minimal delta which brings us back to this place
+	 * immediately. Lather, rinse and repeat...
+	 */
+	if (rcu_needs_cpu(basemono, &next_rcu) || arch_needs_cpu() ||
+	    irq_work_needs_cpu() || local_timer_softirq_pending()) {
 		next_tick = basemono + TICK_NSEC;
 	} else {
 		/*
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 1275175b0946..d9cd6191760b 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -280,6 +280,8 @@ EXPORT_SYMBOL_GPL(ring_buffer_event_data);
 /* Missed count stored at end */
 #define RB_MISSED_STORED	(1 << 30)
 
+#define RB_MISSED_FLAGS		(RB_MISSED_EVENTS|RB_MISSED_STORED)
+
 struct buffer_data_page {
 	u64		 time_stamp;	/* page time stamp */
 	local_t		 commit;	/* write committed index */
@@ -331,7 +333,9 @@ static void rb_init_page(struct buffer_data_page *bpage)
  */
 size_t ring_buffer_page_len(void *page)
 {
-	return local_read(&((struct buffer_data_page *)page)->commit)
+	struct buffer_data_page *bpage = page;
+
+	return (local_read(&bpage->commit) & ~RB_MISSED_FLAGS)
 		+ BUF_PAGE_HDR_SIZE;
 }
 
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 6d4ff15b8c0d..c180e4dc0fb9 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -5844,7 +5844,7 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos,
 		.spd_release	= buffer_spd_release,
 	};
 	struct buffer_ref *ref;
-	int entries, size, i;
+	int entries, i;
 	ssize_t ret = 0;
 
 #ifdef CONFIG_TRACER_MAX_TRACE
@@ -5895,14 +5895,6 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos,
 			break;
 		}
 
-		/*
-		 * zero out any left over data, this is going to
-		 * user land.
-		 */
-		size = ring_buffer_page_len(ref->page);
-		if (size < PAGE_SIZE)
-			memset(ref->page + size, 0, PAGE_SIZE - size);
-
 		page = virt_to_page(ref->page);
 
 		spd.pages[i] = page;
@@ -6629,6 +6621,7 @@ allocate_trace_buffer(struct trace_array *tr, struct trace_buffer *buf, int size
 	buf->data = alloc_percpu(struct trace_array_cpu);
 	if (!buf->data) {
 		ring_buffer_free(buf->buffer);
+		buf->buffer = NULL;
 		return -ENOMEM;
 	}
 
@@ -6652,7 +6645,9 @@ static int allocate_trace_buffers(struct trace_array *tr, int size)
 				    allocate_snapshot ? size : 1);
 	if (WARN_ON(ret)) {
 		ring_buffer_free(tr->trace_buffer.buffer);
+		tr->trace_buffer.buffer = NULL;
 		free_percpu(tr->trace_buffer.data);
+		tr->trace_buffer.data = NULL;
 		return -ENOMEM;
 	}
 	tr->allocated_snapshot = allocate_snapshot;