Merge remote-tracking branch 'common/android-4.4-p' into lineage-18.1-caf-msm8998

* common/android-4.4-p:
  Linux 4.4.296
  xen/netback: don't queue unlimited number of packages
  xen/console: harden hvc_xen against event channel storms
  xen/netfront: harden netfront against event channel storms
  xen/blkfront: harden blkfront against event channel storms
  Input: touchscreen - avoid bitwise vs logical OR warning
  ARM: 8805/2: remove unneeded naked function usage
  net: lan78xx: Avoid unnecessary self assignment
  net: systemport: Add global locking for descriptor lifecycle
  timekeeping: Really make sure wall_to_monotonic isn't positive
  USB: serial: option: add Telit FN990 compositions
  PCI/MSI: Clear PCI_MSIX_FLAGS_MASKALL on error
  USB: gadget: bRequestType is a bitfield, not a enum
  igbvf: fix double free in `igbvf_probe`
  soc/tegra: fuse: Fix bitwise vs. logical OR warning
  nfsd: fix use-after-free due to delegation race
  dm btree remove: fix use after free in rebalance_children()
  recordmcount.pl: look for jgnop instruction as well as bcrl on s390
  mac80211: send ADDBA requests using the tid/queue of the aggregation session
  hwmon: (dell-smm) Fix warning on /proc/i8k creation error
  net: netlink: af_netlink: Prevent empty skb by adding a check on len.
  i2c: rk3x: Handle a spurious start completion interrupt flag
  parisc/agp: Annotate parisc agp init functions with __init
  nfc: fix segfault in nfc_genl_dump_devices_done
  FROMGIT: USB: gadget: bRequestType is a bitfield, not a enum
  Linux 4.4.295
  irqchip: nvic: Fix offset for Interrupt Priority Offsets
  irqchip/irq-gic-v3-its.c: Force synchronisation when issuing INVALL
  iio: accel: kxcjk-1013: Fix possible memory leak in probe and remove
  iio: itg3200: Call iio_trigger_notify_done() on error
  iio: ltr501: Don't return error code in trigger handler
  iio: mma8452: Fix trigger reference couting
  iio: stk3310: Don't return error code in interrupt handler
  usb: core: config: fix validation of wMaxPacketValue entries
  USB: gadget: zero allocate endpoint 0 buffers
  USB: gadget: detect too-big endpoint 0 requests
  net/qla3xxx: fix an error code in ql_adapter_up()
  net, neigh: clear whole pneigh_entry at alloc time
  net: fec: only clear interrupt of handling queue in fec_enet_rx_queue()
  net: altera: set a couple error code in probe()
  net: cdc_ncm: Allow for dwNtbOutMaxSize to be unset or zero
  block: fix ioprio_get(IOPRIO_WHO_PGRP) vs setuid(2)
  tracefs: Set all files to the same group ownership as the mount option
  signalfd: use wake_up_pollfree()
  binder: use wake_up_pollfree()
  wait: add wake_up_pollfree()
  libata: add horkage for ASMedia 1092
  can: pch_can: pch_can_rx_normal: fix use after free
  tracefs: Have new files inherit the ownership of their parent
  ALSA: pcm: oss: Handle missing errors in snd_pcm_oss_change_params*()
  ALSA: pcm: oss: Limit the period size to 16MB
  ALSA: pcm: oss: Fix negative period/buffer sizes
  ALSA: ctl: Fix copy of updated id with element read/write
  mm: bdi: initialize bdi_min_ratio when bdi is unregistered
  nfc: fix potential NULL pointer deref in nfc_genl_dump_ses_done
  can: sja1000: fix use after free in ems_pcmcia_add_card()
  HID: check for valid USB device for many HID drivers
  HID: wacom: fix problems when device is not a valid USB device
  HID: add USB_HID dependancy on some USB HID drivers
  HID: add USB_HID dependancy to hid-chicony
  HID: add USB_HID dependancy to hid-prodikeys
  HID: add hid_is_usb() function to make it simpler for USB detection
  HID: introduce hid_is_using_ll_driver
  UPSTREAM: USB: gadget: zero allocate endpoint 0 buffers
  UPSTREAM: USB: gadget: detect too-big endpoint 0 requests
  Linux 4.4.294
  serial: pl011: Add ACPI SBSA UART match id
  tty: serial: msm_serial: Deactivate RX DMA for polling support
  vgacon: Propagate console boot parameters before calling `vc_resize'
  parisc: Fix "make install" on newer debian releases
  siphash: use _unaligned version by default
  net: qlogic: qlcnic: Fix a NULL pointer dereference in qlcnic_83xx_add_rings()
  natsemi: xtensa: fix section mismatch warnings
  fget: check that the fd still exists after getting a ref to it
  fs: add fget_many() and fput_many()
  sata_fsl: fix warning in remove_proc_entry when rmmod sata_fsl
  sata_fsl: fix UAF in sata_fsl_port_stop when rmmod sata_fsl
  kprobes: Limit max data_size of the kretprobe instances
  net: ethernet: dec: tulip: de4x5: fix possible array overflows in type3_infoblock()
  net: tulip: de4x5: fix the problem that the array 'lp->phy[8]' may be out of bound
  scsi: iscsi: Unblock session then wake up error handler
  s390/setup: avoid using memblock_enforce_memory_limit
  platform/x86: thinkpad_acpi: Fix WWAN device disabled issue after S3 deep
  net: return correct error code
  hugetlb: take PMD sharing into account when flushing tlb/caches
  tty: hvc: replace BUG_ON() with negative return value
  xen/netfront: don't trust the backend response data blindly
  xen/netfront: disentangle tx_skb_freelist
  xen/netfront: don't read data from request on the ring page
  xen/netfront: read response from backend only once
  xen/blkfront: don't trust the backend response data blindly
  xen/blkfront: don't take local copy of a request from the ring page
  xen/blkfront: read response from backend only once
  xen: sync include/xen/interface/io/ring.h with Xen's newest version
  shm: extend forced shm destroy to support objects from several IPC nses
  fuse: release pipe buf after last use
  fuse: fix page stealing
  NFC: add NCI_UNREG flag to eliminate the race
  proc/vmcore: fix clearing user buffer by properly using clear_user()
  hugetlbfs: flush TLBs correctly after huge_pmd_unshare
  tracing: Check pid filtering when creating events
  tcp_cubic: fix spurious Hystart ACK train detections for not-cwnd-limited flows
  scsi: mpt3sas: Fix kernel panic during drive powercycle test
  ARM: socfpga: Fix crash with CONFIG_FORTIRY_SOURCE
  NFSv42: Don't fail clone() unless the OP_CLONE operation failed
  net: ieee802154: handle iftypes as u32
  ASoC: topology: Add missing rwsem around snd_ctl_remove() calls
  ARM: dts: BCM5301X: Add interrupt properties to GPIO node
  xen: detect uninitialized xenbus in xenbus_init
  xen: don't continue xenstore initialization in case of errors
  staging: rtl8192e: Fix use after free in _rtl92e_pci_disconnect()
  ALSA: ctxfi: Fix out-of-range access
  binder: fix test regression due to sender_euid change
  usb: hub: Fix locking issues with address0_mutex
  usb: hub: Fix usb enumeration issue due to address0 race
  USB: serial: option: add Fibocom FM101-GL variants
  USB: serial: option: add Telit LE910S1 0x9200 composition
  staging: ion: Prevent incorrect reference counting behavour

Change-Id: Iadf9f213915d2a02b27ceb3b2144eac827ade329

2 files changed, 54 insertions, 11 deletions

diff --git a/mm/backing-dev.c b/mm/backing-dev.c
index 39fc46c13950..1974b9225982 100644
--- a/mm/backing-dev.c
+++ b/mm/backing-dev.c
@@ -883,6 +883,13 @@ void bdi_unregister(struct backing_dev_info *bdi)
 	wb_shutdown(&bdi->wb);
 	cgwb_bdi_destroy(bdi);
 
+	/*
+	 * If this BDI's min ratio has been set, use bdi_set_min_ratio() to
+	 * update the global bdi_min_ratio.
+	 */
+	if (bdi->min_ratio)
+		bdi_set_min_ratio(bdi, 0);
+
 	if (bdi->dev) {
 		bdi_debug_unregister(bdi);
 		device_unregister(bdi->dev);
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 86a5c9852acf..3184845236ee 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -3273,14 +3273,19 @@ void __unmap_hugepage_range(struct mmu_gather *tlb, struct vm_area_struct *vma,
 	struct page *page;
 	struct hstate *h = hstate_vma(vma);
 	unsigned long sz = huge_page_size(h);
-	const unsigned long mmun_start = start;	/* For mmu_notifiers */
-	const unsigned long mmun_end   = end;	/* For mmu_notifiers */
+	unsigned long mmun_start = start;	/* For mmu_notifiers */
+	unsigned long mmun_end   = end;		/* For mmu_notifiers */
 
 	WARN_ON(!is_vm_hugetlb_page(vma));
 	BUG_ON(start & ~huge_page_mask(h));
 	BUG_ON(end & ~huge_page_mask(h));
 
 	tlb_start_vma(tlb, vma);
+
+	/*
+	 * If sharing possible, alert mmu notifiers of worst case.
+	 */
+	adjust_range_if_pmd_sharing_possible(vma, &mmun_start, &mmun_end);
 	mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end);
 	address = start;
 again:
@@ -3290,8 +3295,11 @@ again:
 			continue;
 
 		ptl = huge_pte_lock(h, mm, ptep);
-		if (huge_pmd_unshare(mm, &address, ptep))
+		if (huge_pmd_unshare(mm, &address, ptep)) {
+			tlb_flush_pmd_range(tlb, address & PUD_MASK, PUD_SIZE);
+			force_flush = 1;
 			goto unlock;
+		}
 
 		pte = huge_ptep_get(ptep);
 		if (huge_pte_none(pte))
@@ -3384,12 +3392,23 @@ void unmap_hugepage_range(struct vm_area_struct *vma, unsigned long start,
 {
 	struct mm_struct *mm;
 	struct mmu_gather tlb;
+	unsigned long tlb_start = start;
+	unsigned long tlb_end = end;
+
+	/*
+	 * If shared PMDs were possibly used within this vma range, adjust
+	 * start/end for worst case tlb flushing.
+	 * Note that we can not be sure if PMDs are shared until we try to
+	 * unmap pages.  However, we want to make sure TLB flushing covers
+	 * the largest possible range.
+	 */
+	adjust_range_if_pmd_sharing_possible(vma, &tlb_start, &tlb_end);
 
 	mm = vma->vm_mm;
 
-	tlb_gather_mmu(&tlb, mm, start, end);
+	tlb_gather_mmu(&tlb, mm, tlb_start, tlb_end);
 	__unmap_hugepage_range(&tlb, vma, start, end, ref_page);
-	tlb_finish_mmu(&tlb, start, end);
+	tlb_finish_mmu(&tlb, tlb_start, tlb_end);
 }
 
 /*
@@ -4065,11 +4084,21 @@ unsigned long hugetlb_change_protection(struct vm_area_struct *vma,
 	pte_t pte;
 	struct hstate *h = hstate_vma(vma);
 	unsigned long pages = 0;
+	unsigned long f_start = start;
+	unsigned long f_end = end;
+	bool shared_pmd = false;
+
+	/*
+	 * In the case of shared PMDs, the area to flush could be beyond
+	 * start/end.  Set f_start/f_end to cover the maximum possible
+	 * range if PMD sharing is possible.
+	 */
+	adjust_range_if_pmd_sharing_possible(vma, &f_start, &f_end);
 
 	BUG_ON(address >= end);
-	flush_cache_range(vma, address, end);
+	flush_cache_range(vma, f_start, f_end);
 
-	mmu_notifier_invalidate_range_start(mm, start, end);
+	mmu_notifier_invalidate_range_start(mm, f_start, f_end);
 	i_mmap_lock_write(vma->vm_file->f_mapping);
 	for (; address < end; address += huge_page_size(h)) {
 		spinlock_t *ptl;
@@ -4080,6 +4109,7 @@ unsigned long hugetlb_change_protection(struct vm_area_struct *vma,
 		if (huge_pmd_unshare(mm, &address, ptep)) {
 			pages++;
 			spin_unlock(ptl);
+			shared_pmd = true;
 			continue;
 		}
 		pte = huge_ptep_get(ptep);
@@ -4114,12 +4144,18 @@ unsigned long hugetlb_change_protection(struct vm_area_struct *vma,
 	 * Must flush TLB before releasing i_mmap_rwsem: x86's huge_pmd_unshare
 	 * may have cleared our pud entry and done put_page on the page table:
 	 * once we release i_mmap_rwsem, another task can do the final put_page
-	 * and that page table be reused and filled with junk.
+	 * and that page table be reused and filled with junk.  If we actually
+	 * did unshare a page of pmds, flush the range corresponding to the pud.
 	 */
-	flush_tlb_range(vma, start, end);
-	mmu_notifier_invalidate_range(mm, start, end);
+	if (shared_pmd) {
+		flush_tlb_range(vma, f_start, f_end);
+		mmu_notifier_invalidate_range(mm, f_start, f_end);
+	} else {
+		flush_tlb_range(vma, start, end);
+		mmu_notifier_invalidate_range(mm, start, end);
+	}
 	i_mmap_unlock_write(vma->vm_file->f_mapping);
-	mmu_notifier_invalidate_range_end(mm, start, end);
+	mmu_notifier_invalidate_range_end(mm, f_start, f_end);
 
 	return pages << h->order;
 }