* tmp-917a9:
ARM/vdso: Mark the vDSO code read-only after init
x86/vdso: Mark the vDSO code read-only after init
lkdtm: Verify that '__ro_after_init' works correctly
arch: Introduce post-init read-only memory
x86/mm: Always enable CONFIG_DEBUG_RODATA and remove the Kconfig option
mm/init: Add 'rodata=off' boot cmdline parameter to disable read-only kernel mappings
asm-generic: Consolidate mark_rodata_ro()
Linux 4.4.6
ld-version: Fix awk regex compile failure
target: Drop incorrect ABORT_TASK put for completed commands
block: don't optimize for non-cloned bio in bio_get_last_bvec()
MIPS: smp.c: Fix uninitialised temp_foreign_map
MIPS: Fix build error when SMP is used without GIC
ovl: fix getcwd() failure after unsuccessful rmdir
ovl: copy new uid/gid into overlayfs runtime inode
userfaultfd: don't block on the last VM updates at exit time
powerpc/powernv: Fix OPAL_CONSOLE_FLUSH prototype and usages
powerpc/powernv: Add a kmsg_dumper that flushes console output on panic
powerpc: Fix dedotify for binutils >= 2.26
Revert "drm/radeon/pm: adjust display configuration after powerstate"
drm/radeon: Fix error handling in radeon_flip_work_func.
drm/amdgpu: Fix error handling in amdgpu_flip_work_func.
Revert "drm/radeon: call hpd_irq_event on resume"
x86/mm: Fix slow_virt_to_phys() for X86_PAE again
gpu: ipu-v3: Do not bail out on missing optional port nodes
mac80211: Fix Public Action frame RX in AP mode
mac80211: check PN correctly for GCMP-encrypted fragmented MPDUs
mac80211: minstrel_ht: fix a logic error in RTS/CTS handling
mac80211: minstrel_ht: set default tx aggregation timeout to 0
mac80211: fix use of uninitialised values in RX aggregation
mac80211: minstrel: Change expected throughput unit back to Kbps
iwlwifi: mvm: inc pending frames counter also when txing non-sta
can: gs_usb: fixed disconnect bug by removing erroneous use of kfree()
cfg80211/wext: fix message ordering
wext: fix message delay/ordering
ovl: fix working on distributed fs as lower layer
ovl: ignore lower entries when checking purity of non-directory entries
ASoC: wm8958: Fix enum ctl accesses in a wrong type
ASoC: wm8994: Fix enum ctl accesses in a wrong type
ASoC: samsung: Use IRQ safe spin lock calls
ASoC: dapm: Fix ctl value accesses in a wrong type
ncpfs: fix a braino in OOM handling in ncp_fill_cache()
jffs2: reduce the breakage on recovery from halfway failed rename()
dmaengine: at_xdmac: fix residue computation
tracing: Fix check for cpu online when event is disabled
s390/dasd: fix diag 0x250 inline assembly
s390/mm: four page table levels vs. fork
KVM: MMU: fix reserved bit check for ept=0/CR0.WP=0/CR4.SMEP=1/EFER.NX=0
KVM: MMU: fix ept=0/pte.u=1/pte.w=0/CR0.WP=0/CR4.SMEP=1/EFER.NX=0 combo
KVM: PPC: Book3S HV: Sanitize special-purpose register values on guest exit
KVM: s390: correct fprs on SIGP (STOP AND) STORE STATUS
KVM: VMX: disable PEBS before a guest entry
kvm: cap halt polling at exactly halt_poll_ns
PCI: Allow a NULL "parent" pointer in pci_bus_assign_domain_nr()
ARM: OMAP2+: hwmod: Introduce ti,no-idle dt property
ARM: dts: dra7: do not gate cpsw clock due to errata i877
ARM: mvebu: fix overlap of Crypto SRAM with PCIe memory window
arm64: account for sparsemem section alignment when choosing vmemmap offset
Linux 4.4.5
drm/amdgpu: fix topaz/tonga gmc assignment in 4.4 stable
modules: fix longstanding /proc/kallsyms vs module insertion race.
drm/i915: refine qemu south bridge detection
drm/i915: more virtual south bridge detection
block: get the 1st and last bvec via helpers
block: check virt boundary in bio_will_gap()
drm/amdgpu: Use drm_calloc_large for VM page_tables array
thermal: cpu_cooling: fix out of bounds access in time_in_idle
i2c: brcmstb: allocate correct amount of memory for regmap
ubi: Fix out of bounds write in volume update code
cxl: Fix PSL timebase synchronization detection
MIPS: traps: Fix SIGFPE information leak from `do_ov' and `do_trap_or_bp'
MIPS: scache: Fix scache init with invalid line size.
USB: serial: option: add support for Quectel UC20
USB: serial: option: add support for Telit LE922 PID 0x1045
USB: qcserial: add Sierra Wireless EM74xx device ID
USB: qcserial: add Dell Wireless 5809e Gobi 4G HSPA+ (rev3)
USB: cp210x: Add ID for Parrot NMEA GPS Flight Recorder
usb: chipidea: otg: change workqueue ci_otg as freezable
ALSA: timer: Fix broken compat timer user status ioctl
ALSA: hdspm: Fix zero-division
ALSA: hdsp: Fix wrong boolean ctl value accesses
ALSA: hdspm: Fix wrong boolean ctl value accesses
ALSA: seq: oss: Don't drain at closing a client
ALSA: pcm: Fix ioctls for X32 ABI
ALSA: timer: Fix ioctls for X32 ABI
ALSA: rawmidi: Fix ioctls X32 ABI
ALSA: hda - Fix mic issues on Acer Aspire E1-472
ALSA: ctl: Fix ioctls for X32 ABI
ALSA: usb-audio: Add a quirk for Plantronics DA45
adv7604: fix tx 5v detect regression
dmaengine: pxa_dma: fix cyclic transfers
Fix directory hardlinks from deleted directories
jffs2: Fix page lock / f->sem deadlock
Revert "jffs2: Fix lock acquisition order bug in jffs2_write_begin"
Btrfs: fix loading of orphan roots leading to BUG_ON
pata-rb532-cf: get rid of the irq_to_gpio() call
tracing: Do not have 'comm' filter override event 'comm' field
ata: ahci: don't mark HotPlugCapable Ports as external/removable
PM / sleep / x86: Fix crash on graph trace through x86 suspend
arm64: vmemmap: use virtual projection of linear region
Adding Intel Lewisburg device IDs for SATA
writeback: flush inode cgroup wb switches instead of pinning super_block
block: bio: introduce helpers to get the 1st and last bvec
libata: Align ata_device's id on a cacheline
libata: fix HDIO_GET_32BIT ioctl
drm/amdgpu: return from atombios_dp_get_dpcd only when error
drm/amdgpu/gfx8: specify which engine to wait before vm flush
drm/amdgpu: apply gfx_v8 fixes to gfx_v7 as well
drm/amdgpu/pm: update current crtc info after setting the powerstate
drm/radeon/pm: update current crtc info after setting the powerstate
drm/ast: Fix incorrect register check for DRAM width
target: Fix WRITE_SAME/DISCARD conversion to linux 512b sectors
iommu/vt-d: Use BUS_NOTIFY_REMOVED_DEVICE in hotplug path
iommu/amd: Fix boot warning when device 00:00.0 is not iommu covered
iommu/amd: Apply workaround for ATS write permission check
arm/arm64: KVM: Fix ioctl error handling
KVM: x86: fix root cause for missed hardware breakpoints
vfio: fix ioctl error handling
Fix cifs_uniqueid_to_ino_t() function for s390x
CIFS: Fix SMB2+ interim response processing for read requests
cifs: fix out-of-bounds access in lease parsing
fbcon: set a default value to blink interval
kvm: x86: Update tsc multiplier on change.
mips/kvm: fix ioctl error handling
parisc: Fix ptrace syscall number and return value modification
PCI: keystone: Fix MSI code that retrieves struct pcie_port pointer
block: Initialize max_dev_sectors to 0
drm/amdgpu: mask out WC from BO on unsupported arches
btrfs: async-thread: Fix a use-after-free error for trace
btrfs: Fix no_space in write and rm loop
Btrfs: fix deadlock running delayed iputs at transaction commit time
drivers: sh: Restore legacy clock domain on SuperH platforms
use ->d_seq to get coherency between ->d_inode and ->d_flags
Linux 4.4.4
iwlwifi: mvm: don't allow sched scans without matches to be started
iwlwifi: update and fix 7265 series PCI IDs
iwlwifi: pcie: properly configure the debug buffer size for 8000
iwlwifi: dvm: fix WoWLAN
security: let security modules use PTRACE_MODE_* with bitmasks
IB/cma: Fix RDMA port validation for iWarp
x86/irq: Plug vector cleanup race
x86/irq: Call irq_force_move_complete with irq descriptor
x86/irq: Remove outgoing CPU from vector cleanup mask
x86/irq: Remove the cpumask allocation from send_cleanup_vector()
x86/irq: Clear move_in_progress before sending cleanup IPI
x86/irq: Remove offline cpus from vector cleanup
x86/irq: Get rid of code duplication
x86/irq: Copy vectormask instead of an AND operation
x86/irq: Check vector allocation early
x86/irq: Reorganize the search in assign_irq_vector
x86/irq: Reorganize the return path in assign_irq_vector
x86/irq: Do not use apic_chip_data.old_domain as temporary buffer
x86/irq: Validate that irq descriptor is still active
x86/irq: Fix a race in x86_vector_free_irqs()
x86/irq: Call chip->irq_set_affinity in proper context
x86/entry/compat: Add missing CLAC to entry_INT80_32
x86/mpx: Fix off-by-one comparison with nr_registers
hpfs: don't truncate the file when delete fails
do_last(): ELOOP failure exit should be done after leaving RCU mode
should_follow_link(): validate ->d_seq after having decided to follow
xen/pcifront: Fix mysterious crashes when NUMA locality information was extracted.
xen/pciback: Save the number of MSI-X entries to be copied later.
xen/pciback: Check PF instead of VF for PCI_COMMAND_MEMORY
xen/scsiback: correct frontend counting
xen/arm: correctly handle DMA mapping of compound pages
ARM: at91/dt: fix typo in sama5d2 pinmux descriptions
ARM: OMAP2+: Fix onenand initialization to avoid filesystem corruption
do_last(): don't let a bogus return value from ->open() et.al. to confuse us
kernel/resource.c: fix muxed resource handling in __request_region()
sunrpc/cache: fix off-by-one in qword_get()
tracing: Fix showing function event in available_events
powerpc/eeh: Fix partial hotplug criterion
KVM: x86: MMU: fix ubsan index-out-of-range warning
KVM: x86: fix conversion of addresses to linear in 32-bit protected mode
KVM: x86: fix missed hardware breakpoints
KVM: arm/arm64: vgic: Ensure bitmaps are long enough
KVM: async_pf: do not warn on page allocation failures
of/irq: Fix msi-map calculation for nonzero rid-base
NFSv4: Fix a dentry leak on alias use
nfs: fix nfs_size_to_loff_t
block: fix use-after-free in dio_bio_complete
bio: return EINTR if copying to user space got interrupted
i2c: i801: Adding Intel Lewisburg support for iTCO
phy: core: fix wrong err handle for phy_power_on
writeback: keep superblock pinned during cgroup writeback association switches
cgroup: make sure a parent css isn't offlined before its children
cpuset: make mm migration asynchronous
PCI/AER: Flush workqueue on device remove to avoid use-after-free
ARCv2: SMP: Emulate IPI to self using software triggered interrupt
ARCv2: STAR 9000950267: Handle return from intr to Delay Slot #2
libata: fix sff host state machine locking while polling
qla2xxx: Fix stale pointer access.
spi: atmel: fix gpio chip-select in case of non-DT platform
target: Fix race with SCF_SEND_DELAYED_TAS handling
target: Fix remote-port TMR ABORT + se_cmd fabric stop
target: Fix TAS handling for multi-session se_node_acls
target: Fix LUN_RESET active TMR descriptor handling
target: Fix LUN_RESET active I/O handling for ACK_KREF
ALSA: hda - Fixing background noise on Dell Inspiron 3162
ALSA: hda - Apply clock gate workaround to Skylake, too
Revert "workqueue: make sure delayed work run in local cpu"
workqueue: handle NUMA_NO_NODE for unbound pool_workqueue lookup
mac80211: Requeue work after scan complete for all VIF types.
rfkill: fix rfkill_fop_read wait_event usage
tick/nohz: Set the correct expiry when switching to nohz/lowres mode
perf stat: Do not clean event's private stats
cdc-acm:exclude Samsung phone 04e8:685d
Revert "Staging: panel: usleep_range is preferred over udelay"
Staging: speakup: Fix getting port information
sd: Optimal I/O size is in bytes, not sectors
libceph: don't spam dmesg with stray reply warnings
libceph: use the right footer size when skipping a message
libceph: don't bail early from try_read() when skipping a message
libceph: fix ceph_msg_revoke()
seccomp: always propagate NO_NEW_PRIVS on tsync
cpufreq: Fix NULL reference crash while accessing policy->governor_data
cpufreq: pxa2xx: fix pxa_cpufreq_change_voltage prototype
hwmon: (ads1015) Handle negative conversion values correctly
hwmon: (gpio-fan) Remove un-necessary speed_index lookup for thermal hook
hwmon: (dell-smm) Blacklist Dell Studio XPS 8000
Thermal: do thermal zone update after a cooling device registered
Thermal: handle thermal zone device properly during system sleep
Thermal: initialize thermal zone device correctly
IB/mlx5: Expose correct maximum number of CQE capacity
IB/qib: Support creating qps with GFP_NOIO flag
IB/qib: fix mcast detach when qp not attached
IB/cm: Fix a recently introduced deadlock
dmaengine: dw: disable BLOCK IRQs for non-cyclic xfer
dmaengine: at_xdmac: fix resume for cyclic transfers
dmaengine: dw: fix cyclic transfer callbacks
dmaengine: dw: fix cyclic transfer setup
nfit: fix multi-interface dimm handling, acpi6.1 compatibility
ACPI / PCI / hotplug: unlock in error path in acpiphp_enable_slot()
ACPI: Revert "ACPI / video: Add Dell Inspiron 5737 to the blacklist"
ACPI / video: Add disable_backlight_sysfs_if quirk for the Toshiba Satellite R830
ACPI / video: Add disable_backlight_sysfs_if quirk for the Toshiba Portege R700
lib: sw842: select crc32
uapi: update install list after nvme.h rename
ideapad-laptop: Add Lenovo Yoga 700 to no_hw_rfkill dmi list
ideapad-laptop: Add Lenovo ideapad Y700-17ISK to no_hw_rfkill dmi list
toshiba_acpi: Fix blank screen at boot if transflective backlight is supported
make sure that freeing shmem fast symlinks is RCU-delayed
drm/radeon/pm: adjust display configuration after powerstate
drm/radeon: Don't hang in radeon_flip_work_func on disabled crtc. (v2)
drm: Fix treatment of drm_vblank_offdelay in drm_vblank_on() (v2)
drm: Fix drm_vblank_pre/post_modeset regression from Linux 4.4
drm: Prevent vblank counter bumps > 1 with active vblank clients. (v2)
drm: No-Op redundant calls to drm_vblank_off() (v2)
drm/radeon: use post-decrement in error handling
drm/qxl: use kmalloc_array to alloc reloc_info in qxl_process_single_command
drm/i915: fix error path in intel_setup_gmbus()
drm/i915/dsi: don't pass arbitrary data to sideband
drm/i915/dsi: defend gpio table against out of bounds access
drm/i915/skl: Don't skip mst encoders in skl_ddi_pll_select()
drm/i915: Don't reject primary plane windowing with color keying enabled on SKL+
drm/i915/dp: fall back to 18 bpp when sink capability is unknown
drm/i915: Make sure DC writes are coherent on flush.
drm/i915: Init power domains early in driver load
drm/i915: intel_hpd_init(): Fix suspend/resume reprobing
drm/i915: Restore inhibiting the load of the default context
drm: fix missing reference counting decrease
drm/radeon: hold reference to fences in radeon_sa_bo_new
drm/radeon: mask out WC from BO on unsupported arches
drm: add helper to check for wc memory support
drm/radeon: fix DP audio support for APU with DCE4.1 display engine
drm/radeon: Add a common function for DFS handling
drm/radeon: cleaned up VCO output settings for DP audio
drm/radeon: properly byte swap vce firmware setup
drm/radeon: clean up fujitsu quirks
drm/radeon: Fix "slow" audio over DP on DCE8+
drm/radeon: call hpd_irq_event on resume
drm/radeon: Fix off-by-one errors in radeon_vm_bo_set_addr
drm/dp/mst: deallocate payload on port destruction
drm/dp/mst: Reverse order of MST enable and clearing VC payload table.
drm/dp/mst: move GUID storage from mgr, port to only mst branch
drm/dp/mst: Calculate MST PBN with 31.32 fixed point
drm: Add drm_fixp_from_fraction and drm_fixp2int_ceil
drm/dp/mst: fix in RAD element access
drm/dp/mst: fix in MSTB RAD initialization
drm/dp/mst: always send reply for UP request
drm/dp/mst: process broadcast messages correctly
drm/nouveau: platform: Fix deferred probe
drm/nouveau/disp/dp: ensure sink is powered up before attempting link training
drm/nouveau/display: Enable vblank irqs after display engine is on again.
drm/nouveau/kms: take mode_config mutex in connector hotplug path
drm/amdgpu/pm: adjust display configuration after powerstate
drm/amdgpu: Don't hang in amdgpu_flip_work_func on disabled crtc.
drm/amdgpu: use post-decrement in error handling
drm/amdgpu: fix issue with overlapping userptrs
drm/amdgpu: hold reference to fences in amdgpu_sa_bo_new (v2)
drm/amdgpu: remove unnecessary forward declaration
drm/amdgpu: fix s4 resume
drm/amdgpu: remove exp hardware support from iceland
drm/amdgpu: don't load MEC2 on topaz
drm/amdgpu: drop topaz support from gmc8 module
drm/amdgpu: pull topaz gmc bits into gmc_v7
drm/amdgpu: The VI specific EXE bit should only apply to GMC v8.0 above
drm/amdgpu: iceland use CI based MC IP
drm/amdgpu: move gmc7 support out of CIK dependency
drm/amdgpu: no need to load MC firmware on fiji
drm/amdgpu: fix amdgpu_bo_pin_restricted VRAM placing v2
drm/amdgpu: fix tonga smu resume
drm/amdgpu: fix lost sync_to if scheduler is enabled.
drm/amdgpu: call hpd_irq_event on resume
drm/amdgpu: Fix off-by-one errors in amdgpu_vm_bo_map
drm/vmwgfx: respect 'nomodeset'
drm/vmwgfx: Fix a width / pitch mismatch on framebuffer updates
drm/vmwgfx: Fix an incorrect lock check
virtio_pci: fix use after free on release
virtio_balloon: fix race between migration and ballooning
virtio_balloon: fix race by fill and leak
regulator: mt6311: MT6311_REGULATOR needs to select REGMAP_I2C
regulator: axp20x: Fix GPIO LDO enable value for AXP22x
clk: exynos: use irqsave version of spin_lock to avoid deadlock with irqs
cxl: use correct operator when writing pcie config space values
sparc64: fix incorrect sign extension in sys_sparc64_personality
EDAC, mc_sysfs: Fix freeing bus' name
EDAC: Robustify workqueues destruction
MIPS: Fix buffer overflow in syscall_get_arguments()
MIPS: Fix some missing CONFIG_CPU_MIPSR6 #ifdefs
MIPS: hpet: Choose a safe value for the ETIME check
MIPS: Loongson-3: Fix SMP_ASK_C0COUNT IPI handler
Revert "MIPS: Fix PAGE_MASK definition"
cputime: Prevent 32bit overflow in time[val|spec]_to_cputime()
time: Avoid signed overflow in timekeeping_get_ns()
Bluetooth: 6lowpan: Fix handling of uncompressed IPv6 packets
Bluetooth: 6lowpan: Fix kernel NULL pointer dereferences
Bluetooth: Fix incorrect removing of IRKs
Bluetooth: Add support of Toshiba Broadcom based devices
Bluetooth: Use continuous scanning when creating LE connections
Drivers: hv: vmbus: Fix a Host signaling bug
tools: hv: vss: fix the write()'s argument: error -> vss_msg
mmc: sdhci: Allow override of get_cd() called from sdhci_request()
mmc: sdhci: Allow override of mmc host operations
mmc: sdhci-pci: Fix card detect race for Intel BXT/APL
mmc: pxamci: fix again read-only gpio detection polarity
mmc: sdhci-acpi: Fix card detect race for Intel BXT/APL
mmc: mmci: fix an ages old detection error
mmc: core: Enable tuning according to the actual timing
mmc: sdhci: Fix sdhci_runtime_pm_bus_on/off()
mmc: mmc: Fix incorrect use of driver strength switching HS200 and HS400
mmc: sdio: Fix invalid vdd in voltage switch power cycle
mmc: sdhci: Fix DMA descriptor with zero data length
mmc: sdhci-pci: Do not default to 33 Ohm driver strength for Intel SPT
mmc: usdhi6rol0: handle NULL data in timeout
clockevents/tcb_clksrc: Prevent disabling an already disabled clock
posix-clock: Fix return code on the poll method's error path
irqchip/gic-v3-its: Fix double ICC_EOIR write for LPI in EOImode==1
irqchip/atmel-aic: Fix wrong bit operation for IRQ priority
irqchip/mxs: Add missing set_handle_irq()
irqchip/omap-intc: Add support for spurious irq handling
coresight: checking for NULL string in coresight_name_match()
dm: fix dm_rq_target_io leak on faults with .request_fn DM w/ blk-mq paths
dm snapshot: fix hung bios when copy error occurs
dm space map metadata: remove unused variable in brb_pop()
tda1004x: only update the frontend properties if locked
vb2: fix a regression in poll() behavior for output,streams
gspca: ov534/topro: prevent a division by 0
si2157: return -EINVAL if firmware blob is too big
media: dvb-core: Don't force CAN_INVERSION_AUTO in oneshot mode
rc: sunxi-cir: Initialize the spinlock properly
namei: ->d_inode of a pinned dentry is stable only for positives
mei: validate request value in client notify request ioctl
mei: fix fasync return value on error
rtlwifi: rtl8723be: Fix module parameter initialization
rtlwifi: rtl8188ee: Fix module parameter initialization
rtlwifi: rtl8192se: Fix module parameter initialization
rtlwifi: rtl8723ae: Fix initialization of module parameters
rtlwifi: rtl8192de: Fix incorrect module parameter descriptions
rtlwifi: rtl8192ce: Fix handling of module parameters
rtlwifi: rtl8192cu: Add missing parameter setup
rtlwifi: rtl_pci: Fix kernel panic
locks: fix unlock when fcntl_setlk races with a close
um: link with -lpthread
uml: fix hostfs mknod()
uml: flush stdout before forking
s390/fpu: signals vs. floating point control register
s390/compat: correct restore of high gprs on signal return
s390/dasd: fix performance drop
s390/dasd: fix refcount for PAV reassignment
s390/dasd: prevent incorrect length error under z/VM after PAV changes
s390: fix normalization bug in exception table sorting
btrfs: initialize the seq counter in struct btrfs_device
Btrfs: Initialize btrfs_root->highest_objectid when loading tree root and subvolume roots
Btrfs: fix transaction handle leak on failure to create hard link
Btrfs: fix number of transaction units required to create symlink
Btrfs: send, don't BUG_ON() when an empty symlink is found
btrfs: statfs: report zero available if metadata are exhausted
Btrfs: igrab inode in writepage
Btrfs: add missing brelse when superblock checksum fails
KVM: s390: fix memory overwrites when vx is disabled
s390/kvm: remove dependency on struct save_area definition
clocksource/drivers/vt8500: Increase the minimum delta
genirq: Validate action before dereferencing it in handle_irq_event_percpu()
mm: numa: quickly fail allocations for NUMA balancing on full nodes
mm: thp: fix SMP race condition between THP page fault and MADV_DONTNEED
ocfs2: unlock inode if deleting inode from orphan fails
drm/i915: shut up gen8+ SDE irq dmesg noise
iw_cxgb3: Fix incorrectly returning error on success
spi: omap2-mcspi: Prevent duplicate gpio_request
drivers: android: correct the size of struct binder_uintptr_t for BC_DEAD_BINDER_DONE
USB: option: add "4G LTE usb-modem U901"
USB: option: add support for SIM7100E
USB: cp210x: add IDs for GE B650V3 and B850V3 boards
usb: dwc3: Fix assignment of EP transfer resources
can: ems_usb: Fix possible tx overflow
dm thin: fix race condition when destroying thin pool workqueue
bcache: Change refill_dirty() to always scan entire disk if necessary
bcache: prevent crash on changing writeback_running
bcache: allows use of register in udev to avoid "device_busy" error.
bcache: unregister reboot notifier if bcache fails to unregister device
bcache: fix a leak in bch_cached_dev_run()
bcache: clear BCACHE_DEV_UNLINK_DONE flag when attaching a backing device
bcache: Add a cond_resched() call to gc
bcache: fix a livelock when we cause a huge number of cache misses
lib/ucs2_string: Correct ucs2 -> utf8 conversion
efi: Add pstore variables to the deletion whitelist
efi: Make efivarfs entries immutable by default
efi: Make our variable validation list include the guid
efi: Do variable name validation tests in utf8
efi: Use ucs2_as_utf8 in efivarfs instead of open coding a bad version
lib/ucs2_string: Add ucs2 -> utf8 helper functions
ARM: 8457/1: psci-smp is built only for SMP
drm/gma500: Use correct unref in the gem bo create function
devm_memremap: Fix error value when memremap failed
KVM: s390: fix guest fprs memory leak
arm64: errata: Add -mpc-relative-literal-loads to build flags
ARM: debug-ll: fix BCM63xx entry for multiplatform
ext4: fix bh->b_state corruption
sctp: Fix port hash table size computation
unix_diag: fix incorrect sign extension in unix_lookup_by_ino
tipc: unlock in error path
rtnl: RTM_GETNETCONF: fix wrong return value
IFF_NO_QUEUE: Fix for drivers not calling ether_setup()
tcp/dccp: fix another race at listener dismantle
route: check and remove route cache when we get route
net_sched fix: reclassification needs to consider ether protocol changes
pppoe: fix reference counting in PPPoE proxy
l2tp: Fix error creating L2TP tunnels
net/mlx4_en: Avoid changing dev->features directly in run-time
net/mlx4_en: Choose time-stamping shift value according to HW frequency
net/mlx4_en: Count HW buffer overrun only once
qmi_wwan: add "4G LTE usb-modem U901"
tcp: md5: release request socket instead of listener
tipc: fix premature addition of node to lookup table
af_unix: Guard against other == sk in unix_dgram_sendmsg
af_unix: Don't set err in unix_stream_read_generic unless there was an error
ipv4: fix memory leaks in ip_cmsg_send() callers
bonding: Fix ARP monitor validation
bpf: fix branch offset adjustment on backjumps after patching ctx expansion
flow_dissector: Fix unaligned access in __skb_flow_dissector when used by eth_get_headlen
net: Copy inner L3 and L4 headers as unaligned on GRE TEB
sctp: translate network order to host order when users get a hmacid
enic: increment devcmd2 result ring in case of timeout
tg3: Fix for tg3 transmit queue 0 timed out when too many gso_segs
net:Add sysctl_max_skb_frags
tcp: do not drop syn_recv on all icmp reports
unix: correctly track in-flight fds in sending process user_struct
ipv6: fix a lockdep splat
ipv6: addrconf: Fix recursive spin lock call
ipv6/udp: use sticky pktinfo egress ifindex on connect()
ipv6: enforce flowi6_oif usage in ip6_dst_lookup_tail()
tcp: beware of alignments in tcp_get_info()
switchdev: Require RTNL mutex to be held when sending FDB notifications
inet: frag: Always orphan skbs inside ip_defrag()
tipc: fix connection abort during subscription cancel
net: dsa: fix mv88e6xxx switches
sctp: allow setting SCTP_SACK_IMMEDIATELY by the application
pptp: fix illegal memory access caused by multiple bind()s
af_unix: fix struct pid memory leak
tcp: fix NULL deref in tcp_v4_send_ack()
lwt: fix rx checksum setting for lwt devices tunneling over ipv6
tunnels: Allow IPv6 UDP checksums to be correctly controlled.
net: dp83640: Fix tx timestamp overflow handling.
gro: Make GRO aware of lightweight tunnels.
af_iucv: Validate socket address length in iucv_sock_bind()
Conflicts:
arch/arm64/Makefile
arch/arm64/include/asm/cacheflush.h
drivers/mmc/host/sdhci.c
drivers/usb/dwc3/ep0.c
drivers/usb/dwc3/gadget.c
kernel/module.c
sound/core/pcm_compat.c
CRs-Fixed: 1010239
Signed-off-by: Runmin Wang <runminw@codeaurora.org>
Change-Id: I41a28636fc9ad91f9d979b191784609476294cdf
NOT FOR STAGING
This patch re-adds the original shmem_set_file to mm/shmem.c
and converts ashmem.c back to using it.
CC: Brian Swetland <swetland@google.com>
CC: Colin Cross <ccross@android.com>
CC: Arve Hjønnevåg <arve@android.com>
CC: Dima Zavin <dima@android.com>
CC: Robert Love <rlove@google.com>
CC: Greg KH <greg@kroah.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Dmitry Vyukov provides a little program, autogenerated by syzkaller,
which races a fault on a mapping of a sparse memfd object, against
truncation of that object below the fault address: run repeatedly for a
few minutes, it reliably generates shmem_evict_inode()'s
WARN_ON(inode->i_blocks).
(But there's nothing specific to memfd here, nor to the fstat which it
happened to use to generate the fault: though that looked suspicious,
since a shmem_recalc_inode() had been added there recently. The same
problem can be reproduced with open+unlink in place of memfd_create, and
with fstatfs in place of fstat.)
v3.7 commit 0f3c42f522 ("tmpfs: change final i_blocks BUG to WARNING")
explains one cause of such a warning (a race with shmem_writepage to
swap), and possible solutions; but we never took it further, and this
syzkaller incident turns out to have a different cause.
shmem_getpage_gfp()'s error recovery, when a freshly allocated page is
then found to be beyond eof, looks plausible - decrementing the alloced
count that was just before incremented - but in fact can go wrong, if a
racing thread (the truncator, for example) gets its shmem_recalc_inode()
in just after our delete_from_page_cache(). delete_from_page_cache()
decrements nrpages, that shmem_recalc_inode() will balance the books by
decrementing alloced itself, then our decrement of alloced take it one
too low: leading to the WARNING when the object is finally evicted.
Once the new page has been exposed in the page cache,
shmem_getpage_gfp() must leave it to shmem_recalc_inode() itself to get
the accounting right in all cases (and not fall through from "trunc:" to
"decused:"). Adjust that error recovery block; and the reinitialization
of info and sbinfo can be removed too.
While we're here, fix shmem_writepage() to avoid the original issue: it
will be safe against a racing shmem_recalc_inode(), if it merely
increments swapped before the shmem_delete_from_page_cache() which
decrements nrpages (but it must then do its own shmem_recalc_inode()
before that, while still in balance, instead of after). (Aside: why do
we shmem_recalc_inode() here in the swap path? Because its raison d'etre
is to cope with clean sparse shmem pages being reclaimed behind our
back: so here when swapping is a good place to look for that case.) But
I've not now managed to reproduce this bug, even without the patch.
I don't see why I didn't do that earlier: perhaps inhibited by the
preference to eliminate shmem_recalc_inode() altogether. Driven by this
incident, I do now have a patch to do so at last; but still want to sit
on it for a bit, there's a couple of questions yet to be resolved.
Signed-off-by: Hugh Dickins <hughd@google.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Andrew stated the following
We have quite a history of remote parts of the kernel using
weird/wrong/inexplicable combinations of __GFP_ flags. I tend
to think that this is because we didn't adequately explain the
interface.
And I don't think that gfp.h really improved much in this area as
a result of this patchset. Could you go through it some time and
decide if we've adequately documented all this stuff?
This patches first moves some GFP flag combinations that are part of the MM
internals to mm/internal.h. The rest of the patch documents the __GFP_FOO
bits under various headings and then documents the flag combinations. It
will not help callers that are brain damaged but the clarity might motivate
some fixes and avoid future mistakes.
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Vitaly Wool <vitalywool@gmail.com>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
LKP reports that v4.2 commit afa2db2fb6 ("tmpfs: truncate prealloc
blocks past i_size") causes a 14.5% slowdown in the AIM9 creat-clo
benchmark.
creat-clo does just what you'd expect from the name, and creat's O_TRUNC
on 0-length file does indeed get into more overhead now shmem_setattr()
tests "0 <= 0" instead of "0 < 0".
I'm not sure how much we care, but I think it would not be too VW-like to
add in a check for whether any pages (or swap) are allocated: if none are
allocated, there's none to remove from the radix_tree. At first I thought
that check would be good enough for the unmaps too, but no: we should not
skip the unlikely case of unmapping pages beyond the new EOF, which were
COWed from holes which have now been reclaimed, leaving none.
This gives me an 8.5% speedup: on Haswell instead of LKP's Westmere, and
running a debug config before and after: I hope those account for the
lesser speedup.
And probably someone has a benchmark where a thousand threads keep on
stat'ing the same file repeatedly: forestall that report by adjusting v4.3
commit 44a30220bc ("shmem: recalculate file inode when fstat") not to
take the spinlock in shmem_getattr() when there's no work to do.
Signed-off-by: Hugh Dickins <hughd@google.com>
Reported-by: Ying Huang <ying.huang@linux.intel.com>
Tested-by: Ying Huang <ying.huang@linux.intel.com>
Cc: Josef Bacik <jbacik@fb.com>
Cc: Yu Zhao <yuzhao@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
After v4.3's commit 0610c25daa ("memcg: fix dirty page migration")
mem_cgroup_migrate() doesn't have much to offer in page migration: convert
migrate_misplaced_transhuge_page() to set_page_memcg() instead.
Then rename mem_cgroup_migrate() to mem_cgroup_replace_page(), since its
remaining callers are replace_page_cache_page() and shmem_replace_page():
both of whom passed lrucare true, so just eliminate that argument.
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Shmem uses shmem_recalc_inode to update i_blocks when it allocates page,
undoes range or swaps. But mm can drop clean page without notifying
shmem. This makes fstat sometimes return out-of-date block size.
The problem can be partially solved when we add
inode_operations->getattr which calls shmem_recalc_inode to update
i_blocks for fstat.
shmem_recalc_inode also updates counter used by statfs and
vm_committed_as. For them the situation is not changed. They still
suffer from the discrepancy after dropping clean page and before the
function is called by aforementioned triggers.
Signed-off-by: Yu Zhao <yuzhao@google.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The shm implementation internally uses shmem or hugetlbfs inodes for shm
segments. As these inodes are never directly exposed to userspace and
only accessed through the shm operations which are already hooked by
security modules, mark the inodes with the S_PRIVATE flag so that inode
security initialization and permission checking is skipped.
This was motivated by the following lockdep warning:
======================================================
[ INFO: possible circular locking dependency detected ]
4.2.0-0.rc3.git0.1.fc24.x86_64+debug #1 Tainted: G W
-------------------------------------------------------
httpd/1597 is trying to acquire lock:
(&ids->rwsem){+++++.}, at: shm_close+0x34/0x130
but task is already holding lock:
(&mm->mmap_sem){++++++}, at: SyS_shmdt+0x4b/0x180
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #3 (&mm->mmap_sem){++++++}:
lock_acquire+0xc7/0x270
__might_fault+0x7a/0xa0
filldir+0x9e/0x130
xfs_dir2_block_getdents.isra.12+0x198/0x1c0 [xfs]
xfs_readdir+0x1b4/0x330 [xfs]
xfs_file_readdir+0x2b/0x30 [xfs]
iterate_dir+0x97/0x130
SyS_getdents+0x91/0x120
entry_SYSCALL_64_fastpath+0x12/0x76
-> #2 (&xfs_dir_ilock_class){++++.+}:
lock_acquire+0xc7/0x270
down_read_nested+0x57/0xa0
xfs_ilock+0x167/0x350 [xfs]
xfs_ilock_attr_map_shared+0x38/0x50 [xfs]
xfs_attr_get+0xbd/0x190 [xfs]
xfs_xattr_get+0x3d/0x70 [xfs]
generic_getxattr+0x4f/0x70
inode_doinit_with_dentry+0x162/0x670
sb_finish_set_opts+0xd9/0x230
selinux_set_mnt_opts+0x35c/0x660
superblock_doinit+0x77/0xf0
delayed_superblock_init+0x10/0x20
iterate_supers+0xb3/0x110
selinux_complete_init+0x2f/0x40
security_load_policy+0x103/0x600
sel_write_load+0xc1/0x750
__vfs_write+0x37/0x100
vfs_write+0xa9/0x1a0
SyS_write+0x58/0xd0
entry_SYSCALL_64_fastpath+0x12/0x76
...
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Reported-by: Morten Stevens <mstevens@fedoraproject.org>
Acked-by: Hugh Dickins <hughd@google.com>
Acked-by: Paul Moore <paul@paul-moore.com>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Eric Paris <eparis@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
One of the rocksdb people noticed that when you do something like this
fallocate(fd, FALLOC_FL_KEEP_SIZE, 0, 10M)
pwrite(fd, buf, 5M, 0)
ftruncate(5M)
on tmpfs, the file would still take up 10M: which led to super fun
issues because we were getting ENOSPC before we thought we should be
getting ENOSPC. This patch fixes the problem, and mirrors what all the
other fs'es do (and was agreed to be the correct behaviour at LSF).
I tested it locally to make sure it worked properly with the following
xfs_io -f -c "falloc -k 0 10M" -c "pwrite 0 5M" -c "truncate 5M" file
Without the patch we have "Blocks: 20480", with the patch we have the
correct value of "Blocks: 10240".
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull vfs updates from Al Viro:
"In this pile: pathname resolution rewrite.
- recursion in link_path_walk() is gone.
- nesting limits on symlinks are gone (the only limit remaining is
that the total amount of symlinks is no more than 40, no matter how
nested).
- "fast" (inline) symlinks are handled without leaving rcuwalk mode.
- stack footprint (independent of the nesting) is below kilobyte now,
about on par with what it used to be with one level of nested
symlinks and ~2.8 times lower than it used to be in the worst case.
- struct nameidata is entirely private to fs/namei.c now (not even
opaque pointers are being passed around).
- ->follow_link() and ->put_link() calling conventions had been
changed; all in-tree filesystems converted, out-of-tree should be
able to follow reasonably easily.
For out-of-tree conversions, see Documentation/filesystems/porting
for details (and in-tree filesystems for examples of conversion).
That has sat in -next since mid-May, seems to survive all testing
without regressions and merges clean with v4.1"
* 'for-linus-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (131 commits)
turn user_{path_at,path,lpath,path_dir}() into static inlines
namei: move saved_nd pointer into struct nameidata
inline user_path_create()
inline user_path_parent()
namei: trim do_last() arguments
namei: stash dfd and name into nameidata
namei: fold path_cleanup() into terminate_walk()
namei: saner calling conventions for filename_parentat()
namei: saner calling conventions for filename_create()
namei: shift nameidata down into filename_parentat()
namei: make filename_lookup() reject ERR_PTR() passed as name
namei: shift nameidata inside filename_lookup()
namei: move putname() call into filename_lookup()
namei: pass the struct path to store the result down into path_lookupat()
namei: uninline set_root{,_rcu}()
namei: be careful with mountpoint crossings in follow_dotdot_rcu()
Documentation: remove outdated information from automount-support.txt
get rid of assorted nameidata-related debris
lustre: kill unused helper
lustre: kill unused macro (LOOKUP_CONTINUE)
...
It appears that, at some point last year, XFS made directory handling
changes which bring it into lockdep conflict with shmem_zero_setup():
it is surprising that mmap() can clone an inode while holding mmap_sem,
but that has been so for many years.
Since those few lockdep traces that I've seen all implicated selinux,
I'm hoping that we can use the __shmem_file_setup(,,,S_PRIVATE) which
v3.13's commit c727709092 ("security: shmem: implement kernel private
shmem inodes") introduced to avoid LSM checks on kernel-internal inodes:
the mmap("/dev/zero") cloned inode is indeed a kernel-internal detail.
This also covers the !CONFIG_SHMEM use of ramfs to support /dev/zero
(and MAP_SHARED|MAP_ANONYMOUS). I thought there were also drivers
which cloned inode in mmap(), but if so, I cannot locate them now.
Reported-and-tested-by: Prarit Bhargava <prarit@redhat.com>
Reported-and-tested-by: Daniel Wagner <wagi@monom.org>
Reported-and-tested-by: Morten Stevens <mstevens@fedoraproject.org>
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
a) instead of storing the symlink body (via nd_set_link()) and returning
an opaque pointer later passed to ->put_link(), ->follow_link() _stores_
that opaque pointer (into void * passed by address by caller) and returns
the symlink body. Returning ERR_PTR() on error, NULL on jump (procfs magic
symlinks) and pointer to symlink body for normal symlinks. Stored pointer
is ignored in all cases except the last one.
Storing NULL for opaque pointer (or not storing it at all) means no call
of ->put_link().
b) the body used to be passed to ->put_link() implicitly (via nameidata).
Now only the opaque pointer is. In the cases when we used the symlink body
to free stuff, ->follow_link() now should store it as opaque pointer in addition
to returning it.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
All places outside of core VFS that checked ->read and ->write for being NULL or
called the methods directly are gone now, so NULL {read,write} with non-NULL
{read,write}_iter will do the right thing in all cases.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
struct kiocb now is a generic I/O container, so move it to fs.h.
Also do a #include diet for aio.h while we're at it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Convert the following where appropriate:
(1) S_ISLNK(dentry->d_inode) to d_is_symlink(dentry).
(2) S_ISREG(dentry->d_inode) to d_is_reg(dentry).
(3) S_ISDIR(dentry->d_inode) to d_is_dir(dentry). This is actually more
complicated than it appears as some calls should be converted to
d_can_lookup() instead. The difference is whether the directory in
question is a real dir with a ->lookup op or whether it's a fake dir with
a ->d_automount op.
In some circumstances, we can subsume checks for dentry->d_inode not being
NULL into this, provided we the code isn't in a filesystem that expects
d_inode to be NULL if the dirent really *is* negative (ie. if we're going to
use d_inode() rather than d_backing_inode() to get the inode pointer).
Note that the dentry type field may be set to something other than
DCACHE_MISS_TYPE when d_inode is NULL in the case of unionmount, where the VFS
manages the fall-through from a negative dentry to a lower layer. In such a
case, the dentry type of the negative union dentry is set to the same as the
type of the lower dentry.
However, if you know d_inode is not NULL at the call site, then you can use
the d_is_xxx() functions even in a filesystem.
There is one further complication: a 0,0 chardev dentry may be labelled
DCACHE_WHITEOUT_TYPE rather than DCACHE_SPECIAL_TYPE. Strictly, this was
intended for special directory entry types that don't have attached inodes.
The following perl+coccinelle script was used:
use strict;
my @callers;
open($fd, 'git grep -l \'S_IS[A-Z].*->d_inode\' |') ||
die "Can't grep for S_ISDIR and co. callers";
@callers = <$fd>;
close($fd);
unless (@callers) {
print "No matches\n";
exit(0);
}
my @cocci = (
'@@',
'expression E;',
'@@',
'',
'- S_ISLNK(E->d_inode->i_mode)',
'+ d_is_symlink(E)',
'',
'@@',
'expression E;',
'@@',
'',
'- S_ISDIR(E->d_inode->i_mode)',
'+ d_is_dir(E)',
'',
'@@',
'expression E;',
'@@',
'',
'- S_ISREG(E->d_inode->i_mode)',
'+ d_is_reg(E)' );
my $coccifile = "tmp.sp.cocci";
open($fd, ">$coccifile") || die $coccifile;
print($fd "$_\n") || die $coccifile foreach (@cocci);
close($fd);
foreach my $file (@callers) {
chomp $file;
print "Processing ", $file, "\n";
system("spatch", "--sp-file", $coccifile, $file, "--in-place", "--no-show-diff") == 0 ||
die "spatch failed";
}
[AV: overlayfs parts skipped]
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pull backing device changes from Jens Axboe:
"This contains a cleanup of how the backing device is handled, in
preparation for a rework of the life time rules. In this part, the
most important change is to split the unrelated nommu mmap flags from
it, but also removing a backing_dev_info pointer from the
address_space (and inode), and a cleanup of other various minor bits.
Christoph did all the work here, I just fixed an oops with pages that
have a swap backing. Arnd fixed a missing export, and Oleg killed the
lustre backing_dev_info from staging. Last patch was from Al,
unexporting parts that are now no longer needed outside"
* 'for-3.20/bdi' of git://git.kernel.dk/linux-block:
Make super_blocks and sb_lock static
mtd: export new mtd_mmap_capabilities
fs: make inode_to_bdi() handle NULL inode
staging/lustre/llite: get rid of backing_dev_info
fs: remove default_backing_dev_info
fs: don't reassign dirty inodes to default_backing_dev_info
nfs: don't call bdi_unregister
ceph: remove call to bdi_unregister
fs: remove mapping->backing_dev_info
fs: export inode_to_bdi and use it in favor of mapping->backing_dev_info
nilfs2: set up s_bdi like the generic mount_bdev code
block_dev: get bdev inode bdi directly from the block device
block_dev: only write bdev inode on close
fs: introduce f_op->mmap_capabilities for nommu mmap support
fs: kill BDI_CAP_SWAP_BACKED
fs: deduplicate noop_backing_dev_info
The body of this function was removed by commit 0a31bc97c8 ("mm:
memcontrol: rewrite uncharge API").
Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
It has been reported that 965GM might trigger
VM_BUG_ON_PAGE(!lrucare && PageLRU(oldpage), oldpage)
in mem_cgroup_migrate when shmem wants to replace a swap cache page
because of shmem_should_replace_page (the page is allocated from an
inappropriate zone). shmem_replace_page expects that the oldpage is not
on LRU list and calls mem_cgroup_migrate without lrucare. This is
obviously incorrect because swapcache pages might be on the LRU list
(e.g. swapin readahead page).
Fix this by enabling lrucare for the migration in shmem_replace_page.
Also clarify that lrucare should be used even if one of the pages might
be on LRU list.
The BUG_ON will trigger only when CONFIG_DEBUG_VM is enabled but even
without that the migration code might leave the old page on an
inappropriate memcg' LRU which is not that critical because the page
would get removed with its last reference but it is still confusing.
Fixes: 0a31bc97c8 ("mm: memcontrol: rewrite uncharge API")
Signed-off-by: Michal Hocko <mhocko@suse.cz>
Reported-by: Chris Wilson <chris@chris-wilson.co.uk>
Reported-by: Dave Airlie <airlied@gmail.com>
Acked-by: Hugh Dickins <hughd@google.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: <stable@vger.kernel.org> [3.17+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Now that we never use the backing_dev_info pointer in struct address_space
we can simply remove it and save 4 to 8 bytes in every inode.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Reviewed-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
This bdi flag isn't too useful - we can determine that a vma is backed by
either swap or shmem trivially in the caller.
This also allows removing the backing_dev_info instaces for swap and shmem
in favor of noop_backing_dev_info.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
Allocate a dentry, initialize it with a whiteout and hash it in the place
of the old dentry. Later the old dentry will be moved away and the
whiteout will remain.
i_mutex protects agains concurrent readdir.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: Hugh Dickins <hughd@google.com>
Pull percpu updates from Tejun Heo:
"A lot of activities on percpu front. Notable changes are...
- percpu allocator now can take @gfp. If @gfp doesn't contain
GFP_KERNEL, it tries to allocate from what's already available to
the allocator and a work item tries to keep the reserve around
certain level so that these atomic allocations usually succeed.
This will replace the ad-hoc percpu memory pool used by
blk-throttle and also be used by the planned blkcg support for
writeback IOs.
Please note that I noticed a bug in how @gfp is interpreted while
preparing this pull request and applied the fix 6ae833c7fe
("percpu: fix how @gfp is interpreted by the percpu allocator")
just now.
- percpu_ref now uses longs for percpu and global counters instead of
ints. It leads to more sparse packing of the percpu counters on
64bit machines but the overhead should be negligible and this
allows using percpu_ref for refcnting pages and in-memory objects
directly.
- The switching between percpu and single counter modes of a
percpu_ref is made independent of putting the base ref and a
percpu_ref can now optionally be initialized in single or killed
mode. This allows avoiding percpu shutdown latency for cases where
the refcounted objects may be synchronously created and destroyed
in rapid succession with only a fraction of them reaching fully
operational status (SCSI probing does this when combined with
blk-mq support). It's also planned to be used to implement forced
single mode to detect underflow more timely for debugging.
There's a separate branch percpu/for-3.18-consistent-ops which cleans
up the duplicate percpu accessors. That branch causes a number of
conflicts with s390 and other trees. I'll send a separate pull
request w/ resolutions once other branches are merged"
* 'for-3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (33 commits)
percpu: fix how @gfp is interpreted by the percpu allocator
blk-mq, percpu_ref: start q->mq_usage_counter in atomic mode
percpu_ref: make INIT_ATOMIC and switch_to_atomic() sticky
percpu_ref: add PERCPU_REF_INIT_* flags
percpu_ref: decouple switching to percpu mode and reinit
percpu_ref: decouple switching to atomic mode and killing
percpu_ref: add PCPU_REF_DEAD
percpu_ref: rename things to prepare for decoupling percpu/atomic mode switch
percpu_ref: replace pcpu_ prefix with percpu_
percpu_ref: minor code and comment updates
percpu_ref: relocate percpu_ref_reinit()
Revert "blk-mq, percpu_ref: implement a kludge for SCSI blk-mq stall during probe"
Revert "percpu: free percpu allocation info for uniprocessor system"
percpu-refcount: make percpu_ref based on longs instead of ints
percpu-refcount: improve WARN messages
percpu: fix locking regression in the failure path of pcpu_alloc()
percpu-refcount: add @gfp to percpu_ref_init()
proportions: add @gfp to init functions
percpu_counter: add @gfp to percpu_counter_init()
percpu_counter: make percpu_counters_lock irq-safe
...
This is designed to avoid a few ifdefs in .c files but it's obnoxious
because it can cause unsuspecting "migrate_page" symbols to get turned into
"NULL".
Just nuke it and use the ifdefs.
Cc: Konstantin Khlebnikov <k.khlebnikov@samsung.com>
Cc: Rafael Aquini <aquini@redhat.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If overwriting an empty directory with rename, then need to drop the extra
nlink.
Test prog:
#include <stdio.h>
#include <fcntl.h>
#include <err.h>
#include <sys/stat.h>
int main(void)
{
const char *test_dir1 = "test-dir1";
const char *test_dir2 = "test-dir2";
int res;
int fd;
struct stat statbuf;
res = mkdir(test_dir1, 0777);
if (res == -1)
err(1, "mkdir(\"%s\")", test_dir1);
res = mkdir(test_dir2, 0777);
if (res == -1)
err(1, "mkdir(\"%s\")", test_dir2);
fd = open(test_dir2, O_RDONLY);
if (fd == -1)
err(1, "open(\"%s\")", test_dir2);
res = rename(test_dir1, test_dir2);
if (res == -1)
err(1, "rename(\"%s\", \"%s\")", test_dir1, test_dir2);
res = fstat(fd, &statbuf);
if (res == -1)
err(1, "fstat(%i)", fd);
if (statbuf.st_nlink != 0) {
fprintf(stderr, "nlink is %lu, should be 0\n", statbuf.st_nlink);
return 1;
}
return 0;
}
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Percpu allocator now supports allocation mask. Add @gfp to
percpu_counter_init() so that !GFP_KERNEL allocation masks can be used
with percpu_counters too.
We could have left percpu_counter_init() alone and added
percpu_counter_init_gfp(); however, the number of users isn't that
high and introducing _gfp variants to all percpu data structures would
be quite ugly, so let's just do the conversion. This is the one with
the most users. Other percpu data structures are a lot easier to
convert.
This patch doesn't make any functional difference.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Jan Kara <jack@suse.cz>
Acked-by: "David S. Miller" <davem@davemloft.net>
Cc: x86@kernel.org
Cc: Jens Axboe <axboe@kernel.dk>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Pull vfs updates from Al Viro:
"Stuff in here:
- acct.c fixes and general rework of mnt_pin mechanism. That allows
to go for delayed-mntput stuff, which will permit mntput() on deep
stack without worrying about stack overflows - fs shutdown will
happen on shallow stack. IOW, we can do Eric's umount-on-rmdir
series without introducing tons of stack overflows on new mntput()
call chains it introduces.
- Bruce's d_splice_alias() patches
- more Miklos' rename() stuff.
- a couple of regression fixes (stable fodder, in the end of branch)
and a fix for API idiocy in iov_iter.c.
There definitely will be another pile, maybe even two. I'd like to
get Eric's series in this time, but even if we miss it, it'll go right
in the beginning of for-next in the next cycle - the tricky part of
prereqs is in this pile"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (40 commits)
fix copy_tree() regression
__generic_file_write_iter(): fix handling of sync error after DIO
switch iov_iter_get_pages() to passing maximal number of pages
fs: mark __d_obtain_alias static
dcache: d_splice_alias should detect loops
exportfs: update Exporting documentation
dcache: d_find_alias needn't recheck IS_ROOT && DCACHE_DISCONNECTED
dcache: remove unused d_find_alias parameter
dcache: d_obtain_alias callers don't all want DISCONNECTED
dcache: d_splice_alias should ignore DCACHE_DISCONNECTED
dcache: d_splice_alias mustn't create directory aliases
dcache: close d_move race in d_splice_alias
dcache: move d_splice_alias
namei: trivial fix to vfs_rename_dir comment
VFS: allow ->d_manage() to declare -EISDIR in rcu_walk mode.
cifs: support RENAME_NOREPLACE
hostfs: support rename flags
shmem: support RENAME_EXCHANGE
shmem: support RENAME_NOREPLACE
btrfs: add RENAME_NOREPLACE
...
If we set SEAL_WRITE on a file, we must make sure there cannot be any
ongoing write-operations on the file. For write() calls, we simply lock
the inode mutex, for mmap() we simply verify there're no writable
mappings. However, there might be pages pinned by AIO, Direct-IO and
similar operations via GUP. We must make sure those do not write to the
memfd file after we set SEAL_WRITE.
As there is no way to notify GUP users to drop pages or to wait for them
to be done, we implement the wait ourself: When setting SEAL_WRITE, we
check all pages for their ref-count. If it's bigger than 1, we know
there's some user of the page. We then mark the page and wait for up to
150ms for those ref-counts to be dropped. If the ref-counts are not
dropped in time, we refuse the seal operation.
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Ryan Lortie <desrt@desrt.ca>
Cc: Lennart Poettering <lennart@poettering.net>
Cc: Daniel Mack <zonque@gmail.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
memfd_create() is similar to mmap(MAP_ANON), but returns a file-descriptor
that you can pass to mmap(). It can support sealing and avoids any
connection to user-visible mount-points. Thus, it's not subject to quotas
on mounted file-systems, but can be used like malloc()'ed memory, but with
a file-descriptor to it.
memfd_create() returns the raw shmem file, so calls like ftruncate() can
be used to modify the underlying inode. Also calls like fstat() will
return proper information and mark the file as regular file. If you want
sealing, you can specify MFD_ALLOW_SEALING. Otherwise, sealing is not
supported (like on all other regular files).
Compared to O_TMPFILE, it does not require a tmpfs mount-point and is not
subject to a filesystem size limit. It is still properly accounted to
memcg limits, though, and to the same overcommit or no-overcommit
accounting as all user memory.
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Ryan Lortie <desrt@desrt.ca>
Cc: Lennart Poettering <lennart@poettering.net>
Cc: Daniel Mack <zonque@gmail.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If two processes share a common memory region, they usually want some
guarantees to allow safe access. This often includes:
- one side cannot overwrite data while the other reads it
- one side cannot shrink the buffer while the other accesses it
- one side cannot grow the buffer beyond previously set boundaries
If there is a trust-relationship between both parties, there is no need
for policy enforcement. However, if there's no trust relationship (eg.,
for general-purpose IPC) sharing memory-regions is highly fragile and
often not possible without local copies. Look at the following two
use-cases:
1) A graphics client wants to share its rendering-buffer with a
graphics-server. The memory-region is allocated by the client for
read/write access and a second FD is passed to the server. While
scanning out from the memory region, the server has no guarantee that
the client doesn't shrink the buffer at any time, requiring rather
cumbersome SIGBUS handling.
2) A process wants to perform an RPC on another process. To avoid huge
bandwidth consumption, zero-copy is preferred. After a message is
assembled in-memory and a FD is passed to the remote side, both sides
want to be sure that neither modifies this shared copy, anymore. The
source may have put sensible data into the message without a separate
copy and the target may want to parse the message inline, to avoid a
local copy.
While SIGBUS handling, POSIX mandatory locking and MAP_DENYWRITE provide
ways to achieve most of this, the first one is unproportionally ugly to
use in libraries and the latter two are broken/racy or even disabled due
to denial of service attacks.
This patch introduces the concept of SEALING. If you seal a file, a
specific set of operations is blocked on that file forever. Unlike locks,
seals can only be set, never removed. Hence, once you verified a specific
set of seals is set, you're guaranteed that no-one can perform the blocked
operations on this file, anymore.
An initial set of SEALS is introduced by this patch:
- SHRINK: If SEAL_SHRINK is set, the file in question cannot be reduced
in size. This affects ftruncate() and open(O_TRUNC).
- GROW: If SEAL_GROW is set, the file in question cannot be increased
in size. This affects ftruncate(), fallocate() and write().
- WRITE: If SEAL_WRITE is set, no write operations (besides resizing)
are possible. This affects fallocate(PUNCH_HOLE), mmap() and
write().
- SEAL: If SEAL_SEAL is set, no further seals can be added to a file.
This basically prevents the F_ADD_SEAL operation on a file and
can be set to prevent others from adding further seals that you
don't want.
The described use-cases can easily use these seals to provide safe use
without any trust-relationship:
1) The graphics server can verify that a passed file-descriptor has
SEAL_SHRINK set. This allows safe scanout, while the client is
allowed to increase buffer size for window-resizing on-the-fly.
Concurrent writes are explicitly allowed.
2) For general-purpose IPC, both processes can verify that SEAL_SHRINK,
SEAL_GROW and SEAL_WRITE are set. This guarantees that neither
process can modify the data while the other side parses it.
Furthermore, it guarantees that even with writable FDs passed to the
peer, it cannot increase the size to hit memory-limits of the source
process (in case the file-storage is accounted to the source).
The new API is an extension to fcntl(), adding two new commands:
F_GET_SEALS: Return a bitset describing the seals on the file. This
can be called on any FD if the underlying file supports
sealing.
F_ADD_SEALS: Change the seals of a given file. This requires WRITE
access to the file and F_SEAL_SEAL may not already be set.
Furthermore, the underlying file must support sealing and
there may not be any existing shared mapping of that file.
Otherwise, EBADF/EPERM is returned.
The given seals are _added_ to the existing set of seals
on the file. You cannot remove seals again.
The fcntl() handler is currently specific to shmem and disabled on all
files. A file needs to explicitly support sealing for this interface to
work. A separate syscall is added in a follow-up, which creates files that
support sealing. There is no intention to support this on other
file-systems. Semantics are unclear for non-volatile files and we lack any
use-case right now. Therefore, the implementation is specific to shmem.
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Ryan Lortie <desrt@desrt.ca>
Cc: Lennart Poettering <lennart@poettering.net>
Cc: Daniel Mack <zonque@gmail.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The memcg uncharging code that is involved towards the end of a page's
lifetime - truncation, reclaim, swapout, migration - is impressively
complicated and fragile.
Because anonymous and file pages were always charged before they had their
page->mapping established, uncharges had to happen when the page type
could still be known from the context; as in unmap for anonymous, page
cache removal for file and shmem pages, and swap cache truncation for swap
pages. However, these operations happen well before the page is actually
freed, and so a lot of synchronization is necessary:
- Charging, uncharging, page migration, and charge migration all need
to take a per-page bit spinlock as they could race with uncharging.
- Swap cache truncation happens during both swap-in and swap-out, and
possibly repeatedly before the page is actually freed. This means
that the memcg swapout code is called from many contexts that make
no sense and it has to figure out the direction from page state to
make sure memory and memory+swap are always correctly charged.
- On page migration, the old page might be unmapped but then reused,
so memcg code has to prevent untimely uncharging in that case.
Because this code - which should be a simple charge transfer - is so
special-cased, it is not reusable for replace_page_cache().
But now that charged pages always have a page->mapping, introduce
mem_cgroup_uncharge(), which is called after the final put_page(), when we
know for sure that nobody is looking at the page anymore.
For page migration, introduce mem_cgroup_migrate(), which is called after
the migration is successful and the new page is fully rmapped. Because
the old page is no longer uncharged after migration, prevent double
charges by decoupling the page's memcg association (PCG_USED and
pc->mem_cgroup) from the page holding an actual charge. The new bits
PCG_MEM and PCG_MEMSW represent the respective charges and are transferred
to the new page during migration.
mem_cgroup_migrate() is suitable for replace_page_cache() as well,
which gets rid of mem_cgroup_replace_page_cache(). However, care
needs to be taken because both the source and the target page can
already be charged and on the LRU when fuse is splicing: grab the page
lock on the charge moving side to prevent changing pc->mem_cgroup of a
page under migration. Also, the lruvecs of both pages change as we
uncharge the old and charge the new during migration, and putback may
race with us, so grab the lru lock and isolate the pages iff on LRU to
prevent races and ensure the pages are on the right lruvec afterward.
Swap accounting is massively simplified: because the page is no longer
uncharged as early as swap cache deletion, a new mem_cgroup_swapout() can
transfer the page's memory+swap charge (PCG_MEMSW) to the swap entry
before the final put_page() in page reclaim.
Finally, page_cgroup changes are now protected by whatever protection the
page itself offers: anonymous pages are charged under the page table lock,
whereas page cache insertions, swapin, and migration hold the page lock.
Uncharging happens under full exclusion with no outstanding references.
Charging and uncharging also ensure that the page is off-LRU, which
serializes against charge migration. Remove the very costly page_cgroup
lock and set pc->flags non-atomically.
[mhocko@suse.cz: mem_cgroup_charge_statistics needs preempt_disable]
[vdavydov@parallels.com: fix flags definition]
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Vladimir Davydov <vdavydov@parallels.com>
Tested-by: Jet Chen <jet.chen@intel.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
Tested-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
These patches rework memcg charge lifetime to integrate more naturally
with the lifetime of user pages. This drastically simplifies the code and
reduces charging and uncharging overhead. The most expensive part of
charging and uncharging is the page_cgroup bit spinlock, which is removed
entirely after this series.
Here are the top-10 profile entries of a stress test that reads a 128G
sparse file on a freshly booted box, without even a dedicated cgroup (i.e.
executing in the root memcg). Before:
15.36% cat [kernel.kallsyms] [k] copy_user_generic_string
13.31% cat [kernel.kallsyms] [k] memset
11.48% cat [kernel.kallsyms] [k] do_mpage_readpage
4.23% cat [kernel.kallsyms] [k] get_page_from_freelist
2.38% cat [kernel.kallsyms] [k] put_page
2.32% cat [kernel.kallsyms] [k] __mem_cgroup_commit_charge
2.18% kswapd0 [kernel.kallsyms] [k] __mem_cgroup_uncharge_common
1.92% kswapd0 [kernel.kallsyms] [k] shrink_page_list
1.86% cat [kernel.kallsyms] [k] __radix_tree_lookup
1.62% cat [kernel.kallsyms] [k] __pagevec_lru_add_fn
After:
15.67% cat [kernel.kallsyms] [k] copy_user_generic_string
13.48% cat [kernel.kallsyms] [k] memset
11.42% cat [kernel.kallsyms] [k] do_mpage_readpage
3.98% cat [kernel.kallsyms] [k] get_page_from_freelist
2.46% cat [kernel.kallsyms] [k] put_page
2.13% kswapd0 [kernel.kallsyms] [k] shrink_page_list
1.88% cat [kernel.kallsyms] [k] __radix_tree_lookup
1.67% cat [kernel.kallsyms] [k] __pagevec_lru_add_fn
1.39% kswapd0 [kernel.kallsyms] [k] free_pcppages_bulk
1.30% cat [kernel.kallsyms] [k] kfree
As you can see, the memcg footprint has shrunk quite a bit.
text data bss dec hex filename
37970 9892 400 48262 bc86 mm/memcontrol.o.old
35239 9892 400 45531 b1db mm/memcontrol.o
This patch (of 4):
The memcg charge API charges pages before they are rmapped - i.e. have an
actual "type" - and so every callsite needs its own set of charge and
uncharge functions to know what type is being operated on. Worse,
uncharge has to happen from a context that is still type-specific, rather
than at the end of the page's lifetime with exclusive access, and so
requires a lot of synchronization.
Rewrite the charge API to provide a generic set of try_charge(),
commit_charge() and cancel_charge() transaction operations, much like
what's currently done for swap-in:
mem_cgroup_try_charge() attempts to reserve a charge, reclaiming
pages from the memcg if necessary.
mem_cgroup_commit_charge() commits the page to the charge once it
has a valid page->mapping and PageAnon() reliably tells the type.
mem_cgroup_cancel_charge() aborts the transaction.
This reduces the charge API and enables subsequent patches to
drastically simplify uncharging.
As pages need to be committed after rmap is established but before they
are added to the LRU, page_add_new_anon_rmap() must stop doing LRU
additions again. Revive lru_cache_add_active_or_unevictable().
[hughd@google.com: fix shmem_unuse]
[hughd@google.com: Add comments on the private use of -EAGAIN]
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: Tejun Heo <tj@kernel.org>
Cc: Vladimir Davydov <vdavydov@parallels.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is really simple in tmpfs since the VFS already takes care of
shuffling the dentries. Just adjust nlink on parent directories and touch
c & mtimes.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Acked-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The gfp arg is not used in shmem_add_to_page_cache. Remove this unused
arg.
Signed-off-by: Wang Sheng-Hui <shhuiw@gmail.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Do we really need an exported alias for __SetPageReferenced()? Its
callers better know what they're doing, in which case the page would not
be already marked referenced. Kill init_page_accessed(), just
__SetPageReferenced() inline.
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Prabhakar Lad <prabhakar.csengg@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
A shared anonymous mapping created without MAP_NORESERVE holds memory
reservation for whole range of shmem segment. Usually there is no way
to change its size, but /proc/<pid>/map_files/... (available if
CONFIG_CHECKPOINT_RESTORE=y) allows that.
This patch adjusts the memory reservation in shmem_setattr().
Signed-off-by: Konstantin Khlebnikov <koct9i@gmail.com>
Acked-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If __shmem_file_setup() fails on struct file allocation it uncharges
memory commitment twice: first by shmem_unacct_size() and second time
implicitly in shmem_evict_inode() when it kills the newly created inode.
This patch removes shmem_unacct_size() from error path if the inode was
already there.
Signed-off-by: Konstantin Khlebnikov <koct9i@gmail.com>
Acked-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
shmem_fault() is the actual culprit in trinity's hole-punch starvation,
and the most significant cause of such problems: since a page faulted is
one that then appears page_mapped(), needing unmap_mapping_range() and
i_mmap_mutex to be unmapped again.
But it is not the only way in which a page can be brought into a hole in
the radix_tree while that hole is being punched; and Vlastimil's testing
implies that if enough other processors are busy filling in the hole,
then shmem_undo_range() can be kept from completing indefinitely.
shmem_file_splice_read() is the main other user of SGP_CACHE, which can
instantiate shmem pagecache pages in the read-only case (without holding
i_mutex, so perhaps concurrently with a hole-punch). Probably it's
silly not to use SGP_READ already (using the ZERO_PAGE for holes): which
ought to be safe, but might bring surprises - not a change to be rushed.
shmem_read_mapping_page_gfp() is an internal interface used by
drivers/gpu/drm GEM (and next by uprobes): it should be okay. And
shmem_file_read_iter() uses the SGP_DIRTY variant of SGP_CACHE, when
called internally by the kernel (perhaps for a stacking filesystem,
which might rely on holes to be reserved): it's unclear whether it could
be provoked to keep hole-punch busy or not.
We could apply the same umbrella as now used in shmem_fault() to
shmem_file_splice_read() and the others; but it looks ugly, and use over
a range raises questions - should it actually be per page? can these get
starved themselves?
The origin of this part of the problem is my v3.1 commit d0823576bf
("mm: pincer in truncate_inode_pages_range"), once it was duplicated
into shmem.c. It seemed like a nice idea at the time, to ensure
(barring RCU lookup fuzziness) that there's an instant when the entire
hole is empty; but the indefinitely repeated scans to ensure that make
it vulnerable.
Revert that "enhancement" to hole-punch from shmem_undo_range(), but
retain the unproblematic rescanning when it's truncating; add a couple
of comments there.
Remove the "indices[0] >= end" test: that is now handled satisfactorily
by the inner loop, and mem_cgroup_uncharge_start()/end() are too light
to be worth avoiding here.
But if we do not always loop indefinitely, we do need to handle the case
of swap swizzled back to page before shmem_free_swap() gets it: add a
retry for that case, as suggested by Konstantin Khlebnikov; and for the
case of page swizzled back to swap, as suggested by Johannes Weiner.
Signed-off-by: Hugh Dickins <hughd@google.com>
Reported-by: Sasha Levin <sasha.levin@oracle.com>
Suggested-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Lukas Czerner <lczerner@redhat.com>
Cc: Dave Jones <davej@redhat.com>
Cc: <stable@vger.kernel.org> [3.1+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit f00cdc6df7 ("shmem: fix faulting into a hole while it's
punched") was buggy: Sasha sent a lockdep report to remind us that
grabbing i_mutex in the fault path is a no-no (write syscall may already
hold i_mutex while faulting user buffer).
We tried a completely different approach (see following patch) but that
proved inadequate: good enough for a rational workload, but not good
enough against trinity - which forks off so many mappings of the object
that contention on i_mmap_mutex while hole-puncher holds i_mutex builds
into serious starvation when concurrent faults force the puncher to fall
back to single-page unmap_mapping_range() searches of the i_mmap tree.
So return to the original umbrella approach, but keep away from i_mutex
this time. We really don't want to bloat every shmem inode with a new
mutex or completion, just to protect this unlikely case from trinity.
So extend the original with wait_queue_head on stack at the hole-punch
end, and wait_queue item on the stack at the fault end.
This involves further use of i_lock to guard against the races: lockdep
has been happy so far, and I see fs/inode.c:unlock_new_inode() holds
i_lock around wake_up_bit(), which is comparable to what we do here.
i_lock is more convenient, but we could switch to shmem's info->lock.
This issue has been tagged with CVE-2014-4171, which will require commit
f00cdc6df7 and this and the following patch to be backported: we
suggest to 3.1+, though in fact the trinity forkbomb effect might go
back as far as 2.6.16, when madvise(,,MADV_REMOVE) came in - or might
not, since much has changed, with i_mmap_mutex a spinlock before 3.0.
Anyone running trinity on 3.0 and earlier? I don't think we need care.
Signed-off-by: Hugh Dickins <hughd@google.com>
Reported-by: Sasha Levin <sasha.levin@oracle.com>
Tested-by: Sasha Levin <sasha.levin@oracle.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Lukas Czerner <lczerner@redhat.com>
Cc: Dave Jones <davej@redhat.com>
Cc: <stable@vger.kernel.org> [3.1+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Under shmem swapping load, I sometimes hit the VM_BUG_ON_PAGE(!PageLRU)
in isolate_lru_pages() at mm/vmscan.c:1281!
Commit 2457aec637 ("mm: non-atomically mark page accessed during page
cache allocation where possible") looks like interrupted work-in-progress.
mm/filemap.c's call to init_page_accessed() is fine, but not mm/shmem.c's
- shmem_write_begin() is clearly wrong to use it after shmem_getpage(),
when the page is always visible in radix_tree, and often already on LRU.
Revert change to shmem_write_begin(), and use init_page_accessed() or
mark_page_accessed() appropriately for SGP_WRITE in shmem_getpage_gfp().
SGP_WRITE also covers shmem_symlink(), which did not mark_page_accessed()
before; but since many other filesystems use [__]page_symlink(), which did
and does mark the page accessed, consider this as rectifying an oversight.
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Prabhakar Lad <prabhakar.csengg@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Trinity finds that mmap access to a hole while it's punched from shmem
can prevent the madvise(MADV_REMOVE) or fallocate(FALLOC_FL_PUNCH_HOLE)
from completing, until the reader chooses to stop; with the puncher's
hold on i_mutex locking out all other writers until it can complete.
It appears that the tmpfs fault path is too light in comparison with its
hole-punching path, lacking an i_data_sem to obstruct it; but we don't
want to slow down the common case.
Extend shmem_fallocate()'s existing range notification mechanism, so
shmem_fault() can refrain from faulting pages into the hole while it's
punched, waiting instead on i_mutex (when safe to sleep; or repeatedly
faulting when not).
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Hugh Dickins <hughd@google.com>
Reported-by: Sasha Levin <sasha.levin@oracle.com>
Tested-by: Sasha Levin <sasha.levin@oracle.com>
Cc: Dave Jones <davej@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
