* lsk-44/linux-linaro-lsk-v4.4:
Linux 4.4.3
modules: fix modparam async_probe request
module: wrapper for symbol name.
itimers: Handle relative timers with CONFIG_TIME_LOW_RES proper
posix-timers: Handle relative timers with CONFIG_TIME_LOW_RES proper
timerfd: Handle relative timers with CONFIG_TIME_LOW_RES proper
prctl: take mmap sem for writing to protect against others
xfs: log mount failures don't wait for buffers to be released
Revert "xfs: clear PF_NOFREEZE for xfsaild kthread"
xfs: inode recovery readahead can race with inode buffer creation
libxfs: pack the agfl header structure so XFS_AGFL_SIZE is correct
ovl: setattr: check permissions before copy-up
ovl: root: copy attr
ovl: check dentry positiveness in ovl_cleanup_whiteouts()
ovl: use a minimal buffer in ovl_copy_xattr
ovl: allow zero size xattr
futex: Drop refcount if requeue_pi() acquired the rtmutex
devm_memremap_release(): fix memremap'd addr handling
ipc/shm: handle removed segments gracefully in shm_mmap()
intel_scu_ipcutil: underflow in scu_reg_access()
mm,thp: khugepaged: call pte flush at the time of collapse
dump_stack: avoid potential deadlocks
radix-tree: fix oops after radix_tree_iter_retry
drivers/hwspinlock: fix race between radix tree insertion and lookup
radix-tree: fix race in gang lookup
MAINTAINERS: return arch/sh to maintained state, with new maintainers
memcg: only free spare array when readers are done
numa: fix /proc/<pid>/numa_maps for hugetlbfs on s390
fs/hugetlbfs/inode.c: fix bugs in hugetlb_vmtruncate_list()
scripts/bloat-o-meter: fix python3 syntax error
dma-debug: switch check from _text to _stext
m32r: fix m32104ut_defconfig build fail
xhci: Fix list corruption in urb dequeue at host removal
Revert "xhci: don't finish a TD if we get a short-transfer event mid TD"
iommu/vt-d: Clear PPR bit to ensure we get more page request interrupts
iommu/vt-d: Fix 64-bit accesses to 32-bit DMAR_GSTS_REG
iommu/vt-d: Fix mm refcounting to hold mm_count not mm_users
iommu/amd: Correct the wrong setting of alias DTE in do_attach
iommu/vt-d: Don't skip PCI devices when disabling IOTLB
Input: vmmouse - fix absolute device registration
string_helpers: fix precision loss for some inputs
Input: i8042 - add Fujitsu Lifebook U745 to the nomux list
Input: elantech - mark protocols v2 and v3 as semi-mt
mm: fix regression in remap_file_pages() emulation
mm: replace vma_lock_anon_vma with anon_vma_lock_read/write
mm: fix mlock accouting
libnvdimm: fix namespace object confusion in is_uuid_busy()
mm: soft-offline: check return value in second __get_any_page() call
perf kvm record/report: 'unprocessable sample' error while recording/reporting guest data
KVM: PPC: Fix ONE_REG AltiVec support
KVM: PPC: Fix emulation of H_SET_DABR/X on POWER8
KVM: arm/arm64: Fix reference to uninitialised VGIC
arm64: dma-mapping: fix handling of devices registered before arch_initcall
ARM: OMAP2+: Fix ppa_zero_params and ppa_por_params for rodata
ARM: OMAP2+: Fix save_secure_ram_context for rodata
ARM: OMAP2+: Fix l2dis_3630 for rodata
ARM: OMAP2+: Fix l2_inv_api_params for rodata
ARM: OMAP2+: Fix wait_dll_lock_timed for rodata
ARM: dts: at91: sama5d4ek: add phy address and IRQ for macb0
ARM: dts: at91: sama5d4 xplained: fix phy0 IRQ type
ARM: dts: at91: sama5d4: fix instance id of DBGU
ARM: dts: at91: sama5d4 xplained: properly mux phy interrupt
ARM: dts: omap5-board-common: enable rtc and charging of backup battery
ARM: dts: Fix omap5 PMIC control lines for RTC writes
ARM: dts: Fix wl12xx missing clocks that cause hangs
ARM: nomadik: fix up SD/MMC DT settings
ARM: 8517/1: ICST: avoid arithmetic overflow in icst_hz()
ARM: 8519/1: ICST: try other dividends than 1
arm64: mm: avoid calling apply_to_page_range on empty range
ARM: mvebu: remove duplicated regulator definition in Armada 388 GP
powerpc/ioda: Set "read" permission when "write" is set
powerpc/powernv: Fix stale PE primary bus
powerpc/eeh: Fix stale cached primary bus
powerpc/eeh: Fix PE location code
SUNRPC: Fixup socket wait for memory
udf: Check output buffer length when converting name to CS0
udf: Prevent buffer overrun with multi-byte characters
udf: limit the maximum number of indirect extents in a row
pNFS/flexfiles: Fix an XDR encoding bug in layoutreturn
nfs: Fix race in __update_open_stateid()
pNFS/flexfiles: Fix an Oopsable typo in ff_mirror_match_fh()
NFS: Fix attribute cache revalidation
cifs: fix erroneous return value
cifs_dbg() outputs an uninitialized buffer in cifs_readdir()
cifs: fix race between call_async() and reconnect()
cifs: Ratelimit kernel log messages
iio: inkern: fix a NULL dereference on error
iio: pressure: mpl115: fix temperature offset sign
iio: light: acpi-als: Report data as processed
iio: dac: mcp4725: set iio name property in sysfs
iio: add IIO_TRIGGER dependency to STK8BA50
iio: add HAS_IOMEM dependency to VF610_ADC
iio-light: Use a signed return type for ltr501_match_samp_freq()
iio:adc:ti_am335x_adc Fix buffered mode by identifying as software buffer.
iio: adis_buffer: Fix out-of-bounds memory access
scsi: fix soft lockup in scsi_remove_target() on module removal
SCSI: Add Marvell Console to VPD blacklist
scsi_dh_rdac: always retry MODE SELECT on command lock violation
drivers/scsi/sg.c: mark VMA as VM_IO to prevent migration
SCSI: fix crashes in sd and sr runtime PM
iscsi-target: Fix potential dead-lock during node acl delete
scsi: add Synology to 1024 sector blacklist
klist: fix starting point removed bug in klist iterators
tracepoints: Do not trace when cpu is offline
tracing: Fix freak link error caused by branch tracer
perf tools: tracepoint_error() can receive e=NULL, robustify it
tools lib traceevent: Fix output of %llu for 64 bit values read on 32 bit machines
ptrace: use fsuid, fsgid, effective creds for fs access checks
Btrfs: fix direct IO requests not reporting IO error to user space
Btrfs: fix hang on extent buffer lock caused by the inode_paths ioctl
Btrfs: fix page reading in extent_same ioctl leading to csum errors
Btrfs: fix invalid page accesses in extent_same (dedup) ioctl
btrfs: properly set the termination value of ctx->pos in readdir
Revert "btrfs: clear PF_NOFREEZE in cleaner_kthread()"
Btrfs: fix fitrim discarding device area reserved for boot loader's use
btrfs: handle invalid num_stripes in sys_array
ext4: don't read blocks from disk after extents being swapped
ext4: fix potential integer overflow
ext4: fix scheduling in atomic on group checksum failure
serial: omap: Prevent DoS using unprivileged ioctl(TIOCSRS485)
serial: 8250_pci: Add Intel Broadwell ports
tty: Add support for PCIe WCH382 2S multi-IO card
pty: make sure super_block is still valid in final /dev/tty close
pty: fix possible use after free of tty->driver_data
staging/speakup: Use tty_ldisc_ref() for paste kworker
phy: twl4030-usb: Fix unbalanced pm_runtime_enable on module reload
phy: twl4030-usb: Relase usb phy on unload
ALSA: seq: Fix double port list deletion
ALSA: seq: Fix leak of pool buffer at concurrent writes
ALSA: pcm: Fix rwsem deadlock for non-atomic PCM stream
ALSA: hda - Cancel probe work instead of flush at remove
x86/mm: Fix vmalloc_fault() to handle large pages properly
x86/uaccess/64: Handle the caching of 4-byte nocache copies properly in __copy_user_nocache()
x86/uaccess/64: Make the __copy_user_nocache() assembly code more readable
x86/mm/pat: Avoid truncation when converting cpa->numpages to address
x86/mm: Fix types used in pgprot cacheability flags translations
Linux 4.4.2
HID: multitouch: fix input mode switching on some Elan panels
mm, vmstat: fix wrong WQ sleep when memory reclaim doesn't make any progress
zsmalloc: fix migrate_zspage-zs_free race condition
zram: don't call idr_remove() from zram_remove()
zram: try vmalloc() after kmalloc()
zram/zcomp: use GFP_NOIO to allocate streams
rtlwifi: rtl8821ae: Fix 5G failure when EEPROM is incorrectly encoded
rtlwifi: rtl8821ae: Fix errors in parameter initialization
crypto: marvell/cesa - fix test in mv_cesa_dev_dma_init()
crypto: atmel-sha - remove calls of clk_prepare() from atomic contexts
crypto: atmel-sha - fix atmel_sha_remove()
crypto: algif_skcipher - Do not set MAY_BACKLOG on the async path
crypto: algif_skcipher - Do not dereference ctx without socket lock
crypto: algif_skcipher - Do not assume that req is unchanged
crypto: user - lock crypto_alg_list on alg dump
EVM: Use crypto_memneq() for digest comparisons
crypto: algif_hash - wait for crypto_ahash_init() to complete
crypto: shash - Fix has_key setting
crypto: chacha20-ssse3 - Align stack pointer to 64 bytes
crypto: caam - make write transactions bufferable on PPC platforms
crypto: algif_skcipher - sendmsg SG marking is off by one
crypto: algif_skcipher - Load TX SG list after waiting
crypto: crc32c - Fix crc32c soft dependency
crypto: algif_skcipher - Fix race condition in skcipher_check_key
crypto: algif_hash - Fix race condition in hash_check_key
crypto: af_alg - Forbid bind(2) when nokey child sockets are present
crypto: algif_skcipher - Remove custom release parent function
crypto: algif_hash - Remove custom release parent function
crypto: af_alg - Allow af_af_alg_release_parent to be called on nokey path
ahci: Intel DNV device IDs SATA
libata: disable forced PORTS_IMPL for >= AHCI 1.3
crypto: algif_skcipher - Add key check exception for cipher_null
crypto: skcipher - Add crypto_skcipher_has_setkey
crypto: algif_hash - Require setkey before accept(2)
crypto: hash - Add crypto_ahash_has_setkey
crypto: algif_skcipher - Add nokey compatibility path
crypto: af_alg - Add nokey compatibility path
crypto: af_alg - Fix socket double-free when accept fails
crypto: af_alg - Disallow bind/setkey/... after accept(2)
crypto: algif_skcipher - Require setkey before accept(2)
sched: Fix crash in sched_init_numa()
ext4 crypto: add missing locking for keyring_key access
iommu/io-pgtable-arm: Ensure we free the final level on teardown
tty: Fix unsafe ldisc reference via ioctl(TIOCGETD)
tty: Retry failed reopen if tty teardown in-progress
tty: Wait interruptibly for tty lock on reopen
n_tty: Fix unsafe reference to "other" ldisc
usb: xhci: apply XHCI_PME_STUCK_QUIRK to Intel Broxton-M platforms
usb: xhci: handle both SSIC ports in PME stuck quirk
usb: phy: msm: fix error handling in probe.
usb: cdc-acm: send zero packet for intel 7260 modem
usb: cdc-acm: handle unlinked urb in acm read callback
USB: option: fix Cinterion AHxx enumeration
USB: serial: option: Adding support for Telit LE922
USB: cp210x: add ID for IAI USB to RS485 adaptor
USB: serial: ftdi_sio: add support for Yaesu SCU-18 cable
usb: hub: do not clear BOS field during reset device
USB: visor: fix null-deref at probe
USB: serial: visor: fix crash on detecting device without write_urbs
ASoC: rt5645: fix the shift bit of IN1 boost
saa7134-alsa: Only frees registered sound cards
ALSA: dummy: Implement timer backend switching more safely
ALSA: hda - Fix bad dereference of jack object
ALSA: hda - Fix speaker output from VAIO AiO machines
Revert "ALSA: hda - Fix noise on Gigabyte Z170X mobo"
ALSA: hda - Fix static checker warning in patch_hdmi.c
ALSA: hda - Add fixup for Mac Mini 7,1 model
ALSA: timer: Fix race between stop and interrupt
ALSA: timer: Fix wrong instance passed to slave callbacks
ALSA: timer: Fix race at concurrent reads
ALSA: timer: Fix link corruption due to double start or stop
ALSA: timer: Fix leftover link at closing
ALSA: timer: Code cleanup
ALSA: seq: Fix lockdep warnings due to double mutex locks
ALSA: seq: Fix race at closing in virmidi driver
ALSA: seq: Fix yet another races among ALSA timer accesses
ASoC: dpcm: fix the BE state on hw_free
ALSA: pcm: Fix potential deadlock in OSS emulation
ALSA: hda/realtek - Support Dell headset mode for ALC225
ALSA: hda/realtek - Support headset mode for ALC225
ALSA: hda/realtek - New codec support of ALC225
ALSA: rawmidi: Fix race at copying & updating the position
ALSA: rawmidi: Remove kernel WARNING for NULL user-space buffer check
ALSA: rawmidi: Make snd_rawmidi_transmit() race-free
ALSA: seq: Degrade the error message for too many opens
ALSA: seq: Fix incorrect sanity check at snd_seq_oss_synth_cleanup()
ALSA: dummy: Disable switching timer backend via sysfs
ALSA: compress: Disable GET_CODEC_CAPS ioctl for some architectures
ALSA: hda - disable dynamic clock gating on Broxton before reset
ALSA: Add missing dependency on CONFIG_SND_TIMER
ALSA: bebob: Use a signed return type for get_formation_index
ALSA: usb-audio: avoid freeing umidi object twice
ALSA: usb-audio: Add native DSD support for PS Audio NuWave DAC
ALSA: usb-audio: Fix OPPO HA-1 vendor ID
ALSA: usb-audio: Add quirk for Microsoft LifeCam HD-6000
ALSA: usb-audio: Fix TEAC UD-501/UD-503/NT-503 usb delay
hrtimer: Handle remaining time proper for TIME_LOW_RES
md/raid: only permit hot-add of compatible integrity profiles
media: i2c: Don't export ir-kbd-i2c module alias
parisc: Fix __ARCH_SI_PREAMBLE_SIZE
parisc: Protect huge page pte changes with spinlocks
printk: do cond_resched() between lines while outputting to consoles
tracing/stacktrace: Show entire trace if passed in function not found
tracing: Fix stacktrace skip depth in trace_buffer_unlock_commit_regs()
PCI: Fix minimum allocation address overwrite
PCI: host: Mark PCIe/PCI (MSI) IRQ cascade handlers as IRQF_NO_THREAD
mtd: nand: assign reasonable default name for NAND drivers
wlcore/wl12xx: spi: fix NULL pointer dereference (Oops)
wlcore/wl12xx: spi: fix oops on firmware load
ocfs2/dlm: clear refmap bit of recovery lock while doing local recovery cleanup
ocfs2/dlm: ignore cleaning the migration mle that is inuse
ALSA: hda - Implement loopback control switch for Realtek and other codecs
block: fix bio splitting on max sectors
base/platform: Fix platform drivers with no probe callback
HID: usbhid: fix recursive deadlock
ocfs2: NFS hangs in __ocfs2_cluster_lock due to race with ocfs2_unblock_lock
block: split bios to max possible length
NFSv4.1/pnfs: Fixup an lo->plh_block_lgets imbalance in layoutreturn
crypto: sun4i-ss - add missing statesize
Linux 4.4.1
arm64: kernel: fix architected PMU registers unconditional access
arm64: kernel: enforce pmuserenr_el0 initialization and restore
arm64: mm: ensure that the zero page is visible to the page table walker
arm64: Clear out any singlestep state on a ptrace detach operation
powerpc/module: Handle R_PPC64_ENTRY relocations
scripts/recordmcount.pl: support data in text section on powerpc
powerpc: Make {cmp}xchg* and their atomic_ versions fully ordered
powerpc: Make value-returning atomics fully ordered
powerpc/tm: Check for already reclaimed tasks
batman-adv: Drop immediate orig_node free function
batman-adv: Drop immediate batadv_hard_iface free function
batman-adv: Drop immediate neigh_ifinfo free function
batman-adv: Drop immediate batadv_neigh_node free function
batman-adv: Drop immediate batadv_orig_ifinfo free function
batman-adv: Avoid recursive call_rcu for batadv_nc_node
batman-adv: Avoid recursive call_rcu for batadv_bla_claim
team: Replace rcu_read_lock with a mutex in team_vlan_rx_kill_vid
net/mlx5_core: Fix trimming down IRQ number
bridge: fix lockdep addr_list_lock false positive splat
ipv6: update skb->csum when CE mark is propagated
net: bpf: reject invalid shifts
phonet: properly unshare skbs in phonet_rcv()
dwc_eth_qos: Fix dma address for multi-fragment skbs
bonding: Prevent IPv6 link local address on enslaved devices
net: preserve IP control block during GSO segmentation
udp: disallow UFO for sockets with SO_NO_CHECK option
net: pktgen: fix null ptr deref in skb allocation
sched,cls_flower: set key address type when present
tcp_yeah: don't set ssthresh below 2
ipv6: tcp: add rcu locking in tcp_v6_send_synack()
net: sctp: prevent writes to cookie_hmac_alg from accessing invalid memory
vxlan: fix test which detect duplicate vxlan iface
unix: properly account for FDs passed over unix sockets
xhci: refuse loading if nousb is used
usb: core: lpm: fix usb3_hardware_lpm sysfs node
USB: cp210x: add ID for ELV Marble Sound Board 1
rtlwifi: fix memory leak for USB device
ASoC: compress: Fix compress device direction check
ASoC: wm5110: Fix PGA clear when disabling DRE
ALSA: timer: Handle disconnection more safely
ALSA: hda - Flush the pending probe work at remove
ALSA: hda - Fix missing module loading with model=generic option
ALSA: hda - Fix bass pin fixup for ASUS N550JX
ALSA: control: Avoid kernel warnings from tlv ioctl with numid 0
ALSA: hrtimer: Fix stall by hrtimer_cancel()
ALSA: pcm: Fix snd_pcm_hw_params struct copy in compat mode
ALSA: seq: Fix snd_seq_call_port_info_ioctl in compat mode
ALSA: hda - Add fixup for Dell Latitidue E6540
ALSA: timer: Fix double unlink of active_list
ALSA: timer: Fix race among timer ioctls
ALSA: hda - fix the headset mic detection problem for a Dell laptop
ALSA: timer: Harden slave timer list handling
ALSA: usb-audio: Fix mixer ctl regression of Native Instrument devices
ALSA: hda - Fix white noise on Dell Latitude E5550
ALSA: seq: Fix race at timer setup and close
ALSA: usb-audio: Avoid calling usb_autopm_put_interface() at disconnect
ALSA: seq: Fix missing NULL check at remove_events ioctl
ALSA: hda - Fixup inverted internal mic for Lenovo E50-80
ALSA: usb: Add native DSD support for Oppo HA-1
x86/mm: Improve switch_mm() barrier comments
x86/mm: Add barriers and document switch_mm()-vs-flush synchronization
x86/boot: Double BOOT_HEAP_SIZE to 64KB
x86/reboot/quirks: Add iMac10,1 to pci_reboot_dmi_table[]
kvm: x86: Fix vmwrite to SECONDARY_VM_EXEC_CONTROL
KVM: x86: correctly print #AC in traces
KVM: x86: expose MSR_TSC_AUX to userspace
x86/xen: don't reset vcpu_info on a cancelled suspend
KEYS: Fix keyring ref leak in join_session_keyring()
Conflicts:
arch/arm64/kernel/perf_event.c
drivers/scsi/sd.c
sound/core/compress_offload.c
Change-Id: I9f77fe42aaae249c24cd6e170202110ab1426878
Signed-off-by: Trilok Soni <tsoni@codeaurora.org>
commit 7162a1e87b3e380133dadc7909081bb70d0a7041 upstream.
Tetsuo Handa reported underflow of NR_MLOCK on munlock.
Testcase:
#include <stdio.h>
#include <stdlib.h>
#include <sys/mman.h>
#define BASE ((void *)0x400000000000)
#define SIZE (1UL << 21)
int main(int argc, char *argv[])
{
void *addr;
system("grep Mlocked /proc/meminfo");
addr = mmap(BASE, SIZE, PROT_READ | PROT_WRITE,
MAP_ANONYMOUS | MAP_PRIVATE | MAP_LOCKED | MAP_FIXED,
-1, 0);
if (addr == MAP_FAILED)
printf("mmap() failed\n"), exit(1);
munmap(addr, SIZE);
system("grep Mlocked /proc/meminfo");
return 0;
}
It happens on munlock_vma_page() due to unfortunate choice of nr_pages
data type:
__mod_zone_page_state(zone, NR_MLOCK, -nr_pages);
For unsigned int nr_pages, implicitly casted to long in
__mod_zone_page_state(), it becomes something around UINT_MAX.
munlock_vma_page() usually called for THP as small pages go though
pagevec.
Let's make nr_pages signed int.
Similar fixes in 6cdb18ad98 ("mm/vmstat: fix overflow in
mod_zone_page_state()") used `long' type, but `int' here is OK for a
count of the number of sub-pages in a huge page.
Fixes: ff6a6da60b ("mm: accelerate munlock() treatment of THP pages")
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Tested-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Michel Lespinasse <walken@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Userspace processes often have multiple allocators that each do
anonymous mmaps to get memory. When examining memory usage of
individual processes or systems as a whole, it is useful to be
able to break down the various heaps that were allocated by
each layer and examine their size, RSS, and physical memory
usage.
This patch adds a user pointer to the shared union in
vm_area_struct that points to a null terminated string inside
the user process containing a name for the vma. vmas that
point to the same address will be merged, but vmas that
point to equivalent strings at different addresses will
not be merged.
Userspace can set the name for a region of memory by calling
prctl(PR_SET_VMA, PR_SET_VMA_ANON_NAME, start, len, (unsigned long)name);
Setting the name to NULL clears it.
The names of named anonymous vmas are shown in /proc/pid/maps
as [anon:<name>] and in /proc/pid/smaps in a new "Name" field
that is only present for named vmas. If the userspace pointer
is no longer valid all or part of the name will be replaced
with "<fault>".
The idea to store a userspace pointer to reduce the complexity
within mm (at the expense of the complexity of reading
/proc/pid/mem) came from Dave Hansen. This results in no
runtime overhead in the mm subsystem other than comparing
the anon_name pointers when considering vma merging. The pointer
is stored in a union with fieds that are only used on file-backed
mappings, so it does not increase memory usage.
Includes fix from Jed Davis <jld@mozilla.com> for typo in
prctl_set_vma_anon_name, which could attempt to set the name
across two vmas at the same time due to a typo, which might
corrupt the vma list. Fix it to use tmp instead of end to limit
the name setting to a single vma at a time.
Change-Id: I9aa7b6b5ef536cd780599ba4e2fba8ceebe8b59f
Signed-off-by: Dmitry Shmidt <dimitrysh@google.com>
The previous patch introduced a flag that specified pages in a VMA should
be placed on the unevictable LRU, but they should not be made present when
the area is created. This patch adds the ability to set this state via
the new mlock system calls.
We add MLOCK_ONFAULT for mlock2 and MCL_ONFAULT for mlockall.
MLOCK_ONFAULT will set the VM_LOCKONFAULT modifier for VM_LOCKED.
MCL_ONFAULT should be used as a modifier to the two other mlockall flags.
When used with MCL_CURRENT, all current mappings will be marked with
VM_LOCKED | VM_LOCKONFAULT. When used with MCL_FUTURE, the mm->def_flags
will be marked with VM_LOCKED | VM_LOCKONFAULT. When used with both
MCL_CURRENT and MCL_FUTURE, all current mappings and mm->def_flags will be
marked with VM_LOCKED | VM_LOCKONFAULT.
Prior to this patch, mlockall() will unconditionally clear the
mm->def_flags any time it is called without MCL_FUTURE. This behavior is
maintained after adding MCL_ONFAULT. If a call to mlockall(MCL_FUTURE) is
followed by mlockall(MCL_CURRENT), the mm->def_flags will be cleared and
new VMAs will be unlocked. This remains true with or without MCL_ONFAULT
in either mlockall() invocation.
munlock() will unconditionally clear both vma flags. munlockall()
unconditionally clears for VMA flags on all VMAs and in the mm->def_flags
field.
Signed-off-by: Eric B Munson <emunson@akamai.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The cost of faulting in all memory to be locked can be very high when
working with large mappings. If only portions of the mapping will be used
this can incur a high penalty for locking.
For the example of a large file, this is the usage pattern for a large
statical language model (probably applies to other statical or graphical
models as well). For the security example, any application transacting in
data that cannot be swapped out (credit card data, medical records, etc).
This patch introduces the ability to request that pages are not
pre-faulted, but are placed on the unevictable LRU when they are finally
faulted in. The VM_LOCKONFAULT flag will be used together with VM_LOCKED
and has no effect when set without VM_LOCKED. Setting the VM_LOCKONFAULT
flag for a VMA will cause pages faulted into that VMA to be added to the
unevictable LRU when they are faulted or if they are already present, but
will not cause any missing pages to be faulted in.
Exposing this new lock state means that we cannot overload the meaning of
the FOLL_POPULATE flag any longer. Prior to this patch it was used to
mean that the VMA for a fault was locked. This means we need the new
FOLL_MLOCK flag to communicate the locked state of a VMA. FOLL_POPULATE
will now only control if the VMA should be populated and in the case of
VM_LOCKONFAULT, it will not be set.
Signed-off-by: Eric B Munson <emunson@akamai.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
With the refactored mlock code, introduce a new system call for mlock.
The new call will allow the user to specify what lock states are being
added. mlock2 is trivial at the moment, but a follow on patch will add a
new mlock state making it useful.
Signed-off-by: Eric B Munson <emunson@akamai.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mlock() allows a user to control page out of program memory, but this
comes at the cost of faulting in the entire mapping when it is allocated.
For large mappings where the entire area is not necessary this is not
ideal. Instead of forcing all locked pages to be present when they are
allocated, this set creates a middle ground. Pages are marked to be
placed on the unevictable LRU (locked) when they are first used, but they
are not faulted in by the mlock call.
This series introduces a new mlock() system call that takes a flags
argument along with the start address and size. This flags argument gives
the caller the ability to request memory be locked in the traditional way,
or to be locked after the page is faulted in. A new MCL flag is added to
mirror the lock on fault behavior from mlock() in mlockall().
There are two main use cases that this set covers. The first is the
security focussed mlock case. A buffer is needed that cannot be written
to swap. The maximum size is known, but on average the memory used is
significantly less than this maximum. With lock on fault, the buffer is
guaranteed to never be paged out without consuming the maximum size every
time such a buffer is created.
The second use case is focussed on performance. Portions of a large file
are needed and we want to keep the used portions in memory once accessed.
This is the case for large graphical models where the path through the
graph is not known until run time. The entire graph is unlikely to be
used in a given invocation, but once a node has been used it needs to stay
resident for further processing. Given these constraints we have a number
of options. We can potentially waste a large amount of memory by mlocking
the entire region (this can also cause a significant stall at startup as
the entire file is read in). We can mlock every page as we access them
without tracking if the page is already resident but this introduces large
overhead for each access. The third option is mapping the entire region
with PROT_NONE and using a signal handler for SIGSEGV to
mprotect(PROT_READ) and mlock() the needed page. Doing this page at a
time adds a significant performance penalty. Batching can be used to
mitigate this overhead, but in order to safely avoid trying to mprotect
pages outside of the mapping, the boundaries of each mapping to be used in
this way must be tracked and available to the signal handler. This is
precisely what the mm system in the kernel should already be doing.
For mlock(MLOCK_ONFAULT) the user is charged against RLIMIT_MEMLOCK as if
mlock(MLOCK_LOCKED) or mmap(MAP_LOCKED) was used, so when the VMA is
created not when the pages are faulted in. For mlockall(MCL_ONFAULT) the
user is charged as if MCL_FUTURE was used. This decision was made to keep
the accounting checks out of the page fault path.
To illustrate the benefit of this set I wrote a test program that mmaps a
5 GB file filled with random data and then makes 15,000,000 accesses to
random addresses in that mapping. The test program was run 20 times for
each setup. Results are reported for two program portions, setup and
execution. The setup phase is calling mmap and optionally mlock on the
entire region. For most experiments this is trivial, but it highlights
the cost of faulting in the entire region. Results are averages across
the 20 runs in milliseconds.
mmap with mlock(MLOCK_LOCKED) on entire range:
Setup avg: 8228.666
Processing avg: 8274.257
mmap with mlock(MLOCK_LOCKED) before each access:
Setup avg: 0.113
Processing avg: 90993.552
mmap with PROT_NONE and signal handler and batch size of 1 page:
With the default value in max_map_count, this gets ENOMEM as I attempt
to change the permissions, after upping the sysctl significantly I get:
Setup avg: 0.058
Processing avg: 69488.073
mmap with PROT_NONE and signal handler and batch size of 8 pages:
Setup avg: 0.068
Processing avg: 38204.116
mmap with PROT_NONE and signal handler and batch size of 16 pages:
Setup avg: 0.044
Processing avg: 29671.180
mmap with mlock(MLOCK_ONFAULT) on entire range:
Setup avg: 0.189
Processing avg: 17904.899
The signal handler in the batch cases faulted in memory in two steps to
avoid having to know the start and end of the faulting mapping. The first
step covers the page that caused the fault as we know that it will be
possible to lock. The second step speculatively tries to mlock and
mprotect the batch size - 1 pages that follow. There may be a clever way
to avoid this without having the program track each mapping to be covered
by this handeler in a globally accessible structure, but I could not find
it. It should be noted that with a large enough batch size this two step
fault handler can still cause the program to crash if it reaches far
beyond the end of the mapping.
These results show that if the developer knows that a majority of the
mapping will be used, it is better to try and fault it in at once,
otherwise mlock(MLOCK_ONFAULT) is significantly faster.
The performance cost of these patches are minimal on the two benchmarks I
have tested (stream and kernbench). The following are the average values
across 20 runs of stream and 10 runs of kernbench after a warmup run whose
results were discarded.
Avg throughput in MB/s from stream using 1000000 element arrays
Test 4.2-rc1 4.2-rc1+lock-on-fault
Copy: 10,566.5 10,421
Scale: 10,685 10,503.5
Add: 12,044.1 11,814.2
Triad: 12,064.8 11,846.3
Kernbench optimal load
4.2-rc1 4.2-rc1+lock-on-fault
Elapsed Time 78.453 78.991
User Time 64.2395 65.2355
System Time 9.7335 9.7085
Context Switches 22211.5 22412.1
Sleeps 14965.3 14956.1
This patch (of 6):
Extending the mlock system call is very difficult because it currently
does not take a flags argument. A later patch in this set will extend
mlock to support a middle ground between pages that are locked and faulted
in immediately and unlocked pages. To pave the way for the new system
call, the code needs some reorganization so that all the actual entry
point handles is checking input and translating to VMA flags.
Signed-off-by: Eric B Munson <emunson@akamai.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In mlockall syscall wrapper after out-label for goto code just doing
return. Remove goto out statements and return error values directly.
Also instead of rewriting ret variable before every if-check move returns
to 'error'-like path under if-check.
Objdump asm listing showed me reducing by few asm lines. Object file size
descreased from 220592 bytes to 220528 bytes for me (for aarch64).
Signed-off-by: Alexey Klimov <klimov.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
vma->vm_userfaultfd_ctx is yet another vma parameter that vma_merge
must be aware about so that we can merge vmas back like they were
originally before arming the userfaultfd on some memory range.
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Cc: Sanidhya Kashyap <sanidhya.gatech@gmail.com>
Cc: zhang.zhanghailiang@huawei.com
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Andres Lagar-Cavilla <andreslc@google.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Hugh Dickins <hughd@google.com>
Cc: Peter Feiner <pfeiner@google.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: "Huangpeng (Peter)" <peter.huangpeng@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
It's odd that we have populate_vma_page_range() and __mm_populate() in
mm/mlock.c. It's implementation of generic memory population and mlocking
is one of possible side effect, if VM_LOCKED is set.
__get_user_pages() is core of the implementation. Let's move the code
into mm/gup.c.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Michel Lespinasse <walken@google.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>
This is praparation to moving mm_populate()-related code out of
mm/mlock.c.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Michel Lespinasse <walken@google.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>
__mlock_vma_pages_range() doesn't necessarily mlock pages. It depends on
vma flags. The same codepath is used for MAP_POPULATE.
Let's rename __mlock_vma_pages_range() to populate_vma_page_range().
This patch also drops mlock_vma_pages_range() references from
documentation. It has gone in cea10a19b7 ("mm: directly use
__mlock_vma_pages_range() in find_extend_vma()").
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Michel Lespinasse <walken@google.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>
After commit a1fde08c74 ("VM: skip the stack guard page lookup in
get_user_pages only for mlock") FOLL_MLOCK has lost its original
meaning: we don't necessarily mlock the page if the flags is set -- we
also take VM_LOCKED into consideration.
Since we use the same codepath for __mm_populate(), let's rename
FOLL_MLOCK to FOLL_POPULATE.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Michel Lespinasse <walken@google.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>
A userspace call to mmap(MAP_LOCKED) may result in the successful locking
of memory while also producing a confusing audit log denial. can_do_mlock
checks capable and rlimit. If either of these return positive
can_do_mlock returns true. The capable check leads to an LSM hook used by
apparmour and selinux which produce the audit denial. Reordering so
rlimit is checked first eliminates the denial on success, only recording a
denial when the lock is unsuccessful as a result of the denial.
Signed-off-by: Jeff Vander Stoep <jeffv@google.com>
Acked-by: Nick Kralevich <nnk@google.com>
Cc: Jeff Vander Stoep <jeffv@google.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Paul Cassella <cassella@cray.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull RCU updates from Ingo Molnar:
"The main changes in this cycle were:
- changes related to No-CBs CPUs and NO_HZ_FULL
- RCU-tasks implementation
- torture-test updates
- miscellaneous fixes
- locktorture updates
- RCU documentation updates"
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (81 commits)
workqueue: Use cond_resched_rcu_qs macro
workqueue: Add quiescent state between work items
locktorture: Cleanup header usage
locktorture: Cannot hold read and write lock
locktorture: Fix __acquire annotation for spinlock irq
locktorture: Support rwlocks
rcu: Eliminate deadlock between CPU hotplug and expedited grace periods
locktorture: Document boot/module parameters
rcutorture: Rename rcutorture_runnable parameter
locktorture: Add test scenario for rwsem_lock
locktorture: Add test scenario for mutex_lock
locktorture: Make torture scripting account for new _runnable name
locktorture: Introduce torture context
locktorture: Support rwsems
locktorture: Add infrastructure for torturing read locks
torture: Address race in module cleanup
locktorture: Make statistics generic
locktorture: Teach about lock debugging
locktorture: Support mutexes
locktorture: Add documentation
...
Dump the contents of the relevant struct_mm when we hit the bug condition.
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Trivially convert a few VM_BUG_ON calls to VM_BUG_ON_VMA to extract
more information when they trigger.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Hugh Dickins <hughd@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Michel Lespinasse <walken@google.com>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
RCU-tasks requires the occasional voluntary context switch
from CPU-bound in-kernel tasks. In some cases, this requires
instrumenting cond_resched(). However, there is some reluctance
to countenance unconditionally instrumenting cond_resched() (see
http://lwn.net/Articles/603252/), so this commit creates a separate
cond_resched_rcu_qs() that may be used in place of cond_resched() in
locations prone to long-duration in-kernel looping.
This commit currently instruments only RCU-tasks. Future possibilities
include also instrumenting RCU, RCU-bh, and RCU-sched in order to reduce
IPI usage.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Add a comment describing the circumstances in which
__lock_page_or_retry() will or will not release the mmap_sem when
returning 0.
Add comments to lock_page_or_retry()'s callers (filemap_fault(),
do_swap_page()) noting the impact on VM_FAULT_RETRY returns.
Add comments on up the call tree, particularly replacing the false "We
return with mmap_sem still held" comments.
Signed-off-by: Paul Cassella <cassella@cray.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
A BUG_ON(!PageLocked) was triggered in mlock_vma_page() by Sasha Levin
fuzzing with trinity. The call site try_to_unmap_cluster() does not lock
the pages other than its check_page parameter (which is already locked).
The BUG_ON in mlock_vma_page() is not documented and its purpose is
somewhat unclear, but apparently it serializes against page migration,
which could otherwise fail to transfer the PG_mlocked flag. This would
not be fatal, as the page would be eventually encountered again, but
NR_MLOCK accounting would become distorted nevertheless. This patch adds
a comment to the BUG_ON in mlock_vma_page() and munlock_vma_page() to that
effect.
The call site try_to_unmap_cluster() is fixed so that for page !=
check_page, trylock_page() is attempted (to avoid possible deadlocks as we
already have check_page locked) and mlock_vma_page() is performed only
upon success. If the page lock cannot be obtained, the page is left
without PG_mlocked, which is again not a problem in the whole unevictable
memory design.
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Bob Liu <bob.liu@oracle.com>
Reported-by: Sasha Levin <sasha.levin@oracle.com>
Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Cc: Michel Lespinasse <walken@google.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Most of the VM_BUG_ON assertions are performed on a page. Usually, when
one of these assertions fails we'll get a BUG_ON with a call stack and
the registers.
I've recently noticed based on the requests to add a small piece of code
that dumps the page to various VM_BUG_ON sites that the page dump is
quite useful to people debugging issues in mm.
This patch adds a VM_BUG_ON_PAGE(cond, page) which beyond doing what
VM_BUG_ON() does, also dumps the page before executing the actual
BUG_ON.
[akpm@linux-foundation.org: fix up includes]
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Since commit ff6a6da60b ("mm: accelerate munlock() treatment of THP
pages") munlock skips tail pages of a munlocked THP page. There is some
attempt to prevent bad consequences of racing with a THP page split, but
code inspection indicates that there are two problems that may lead to a
non-fatal, yet wrong outcome.
First, __split_huge_page_refcount() copies flags including PageMlocked
from the head page to the tail pages. Clearing PageMlocked by
munlock_vma_page() in the middle of this operation might result in part
of tail pages left with PageMlocked flag. As the head page still
appears to be a THP page until all tail pages are processed,
munlock_vma_page() might think it munlocked the whole THP page and skip
all the former tail pages. Before ff6a6da60, those pages would be
cleared in further iterations of munlock_vma_pages_range(), but NR_MLOCK
would still become undercounted (related the next point).
Second, NR_MLOCK accounting is based on call to hpage_nr_pages() after
the PageMlocked is cleared. The accounting might also become
inconsistent due to race with __split_huge_page_refcount()
- undercount when HUGE_PMD_NR is subtracted, but some tail pages are
left with PageMlocked set and counted again (only possible before
ff6a6da60)
- overcount when hpage_nr_pages() sees a normal page (split has already
finished), but the parallel split has meanwhile cleared PageMlocked from
additional tail pages
This patch prevents both problems via extending the scope of lru_lock in
munlock_vma_page(). This is convenient because:
- __split_huge_page_refcount() takes lru_lock for its whole operation
- munlock_vma_page() typically takes lru_lock anyway for page isolation
As this becomes a second function where page isolation is done with
lru_lock already held, factor this out to a new
__munlock_isolate_lru_page() function and clean up the code around.
[akpm@linux-foundation.org: avoid a coding-style ugly]
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Michel Lespinasse <walken@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
All mlock related syscalls prepare lock limits, lengths and start
parameters with the mmap_sem held. Move this logic outside of the
critical region. For the case of mlock, continue incrementing the
amount already locked by mm->locked_vm with the rwsem taken.
Signed-off-by: Davidlohr Bueso <davidlohr@hp.com>
Cc: Rik van Riel <riel@redhat.com>
Reviewed-by: Michel Lespinasse <walken@google.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 7225522bb4 ("mm: munlock: batch non-THP page isolation and
munlock+putback using pagevec" introduced __munlock_pagevec() to speed
up munlock by holding lru_lock over multiple isolated pages. Pages that
fail to be isolated are put_page()d immediately, also within the lock.
This can lead to deadlock when __munlock_pagevec() becomes the holder of
the last page pin and put_page() leads to __page_cache_release() which
also locks lru_lock. The deadlock has been observed by Sasha Levin
using trinity.
This patch avoids the deadlock by deferring put_page() operations until
lru_lock is released. Another pagevec (which is also used by later
phases of the function is reused to gather the pages for put_page()
operation.
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reported-by: Sasha Levin <sasha.levin@oracle.com>
Cc: Michel Lespinasse <walken@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Since commit ff6a6da60b ("mm: accelerate munlock() treatment of THP
pages") munlock skips tail pages of a munlocked THP page. However, when
the head page already has PageMlocked unset, it will not skip the tail
pages.
Commit 7225522bb4 ("mm: munlock: batch non-THP page isolation and
munlock+putback using pagevec") has added a PageTransHuge() check which
contains VM_BUG_ON(PageTail(page)). Sasha Levin found this triggered
using trinity, on the first tail page of a THP page without PageMlocked
flag.
This patch fixes the issue by skipping tail pages also in the case when
PageMlocked flag is unset. There is still a possibility of race with
THP page split between clearing PageMlocked and determining how many
pages to skip. The race might result in former tail pages not being
skipped, which is however no longer a bug, as during the skip the
PageTail flags are cleared.
However this race also affects correctness of NR_MLOCK accounting, which
is to be fixed in a separate patch.
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reported-by: Sasha Levin <sasha.levin@oracle.com>
Cc: Michel Lespinasse <walken@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: Bob Liu <bob.liu@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The function __munlock_pagevec_fill() introduced in commit 7a8010cd36
("mm: munlock: manual pte walk in fast path instead of
follow_page_mask()") uses pmd_addr_end() for restricting its operation
within current page table.
This is insufficient on architectures/configurations where pmd is folded
and pmd_addr_end() just returns the end of the full range to be walked.
In this case, it allows pte++ to walk off the end of a page table
resulting in unpredictable behaviour.
This patch fixes the function by using pgd_addr_end() and pud_addr_end()
before pmd_addr_end(), which will yield correct page table boundary on
all configurations. This is similar to what existing page walkers do
when walking each level of the page table.
Additionaly, the patch clarifies a comment for get_locked_pte() call in the
function.
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Reviewed-by: Bob Liu <bob.liu@oracle.com>
Cc: Jörn Engel <joern@logfs.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michel Lespinasse <walken@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There is a loop in do_mlockall() that lacks a preemption point, which
means that the following can happen on non-preemptible builds of the
kernel. Dave Jones reports:
"My fuzz tester keeps hitting this. Every instance shows the non-irq
stack came in from mlockall. I'm only seeing this on one box, but
that has more ram (8gb) than my other machines, which might explain
it.
INFO: rcu_preempt self-detected stall on CPU { 3} (t=6500 jiffies g=470344 c=470343 q=0)
sending NMI to all CPUs:
NMI backtrace for cpu 3
CPU: 3 PID: 29664 Comm: trinity-child2 Not tainted 3.11.0-rc1+ #32
Call Trace:
lru_add_drain_all+0x15/0x20
SyS_mlockall+0xa5/0x1a0
tracesys+0xdd/0xe2"
This commit addresses this problem by inserting the required preemption
point.
Reported-by: Dave Jones <davej@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@gmail.com>
Cc: Michel Lespinasse <walken@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently munlock_vma_pages_range() calls follow_page_mask() to obtain
each individual struct page. This entails repeated full page table
translations and page table lock taken for each page separately.
This patch avoids the costly follow_page_mask() where possible, by
iterating over ptes within single pmd under single page table lock. The
first pte is obtained by get_locked_pte() for non-THP page acquired by the
initial follow_page_mask(). The rest of the on-stack pagevec for munlock
is filled up using pte_walk as long as pte_present() and vm_normal_page()
are sufficient to obtain the struct page.
After this patch, a 14% speedup was measured for munlocking a 56GB large
memory area with THP disabled.
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Jörn Engel <joern@logfs.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michel Lespinasse <walken@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The performance of the fast path in munlock_vma_range() can be further
improved by avoiding atomic ops of a redundant get_page()/put_page() pair.
When calling get_page() during page isolation, we already have the pin
from follow_page_mask(). This pin will be then returned by
__pagevec_lru_add(), after which we do not reference the pages anymore.
After this patch, an 8% speedup was measured for munlocking a 56GB large
memory area with THP disabled.
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Jörn Engel <joern@logfs.org>
Acked-by: Mel Gorman <mgorman@suse.de>
Cc: Michel Lespinasse <walken@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
After introducing batching by pagevecs into munlock_vma_range(), we can
further improve performance by bypassing the copying into per-cpu pagevec
and the get_page/put_page pair associated with that. Instead we perform
LRU putback directly from our pagevec. However, this is possible only for
single-mapped pages that are evictable after munlock. Unevictable pages
require rechecking after putting on the unevictable list, so for those we
fallback to putback_lru_page(), hich handles that.
After this patch, a 13% speedup was measured for munlocking a 56GB large
memory area with THP disabled.
[akpm@linux-foundation.org:clarify comment]
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Jörn Engel <joern@logfs.org>
Acked-by: Mel Gorman <mgorman@suse.de>
Cc: Michel Lespinasse <walken@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Depending on previous batch which introduced batched isolation in
munlock_vma_range(), we can batch also the updates of NR_MLOCK page stats.
After the whole pagevec is processed for page isolation, the stats are
updated only once with the number of successful isolations. There were
however no measurable perfomance gains.
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Jörn Engel <joern@logfs.org>
Acked-by: Mel Gorman <mgorman@suse.de>
Cc: Michel Lespinasse <walken@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently, munlock_vma_range() calls munlock_vma_page on each page in a
loop, which results in repeated taking and releasing of the lru_lock
spinlock for isolating pages one by one. This patch batches the munlock
operations using an on-stack pagevec, so that isolation is done under
single lru_lock. For THP pages, the old behavior is preserved as they
might be split while putting them into the pagevec. After this patch, a
9% speedup was measured for munlocking a 56GB large memory area with THP
disabled.
A new function __munlock_pagevec() is introduced that takes a pagevec and:
1) It clears PageMlocked and isolates all pages under lru_lock. Zone page
stats can be also updated using the variant which assumes disabled
interrupts. 2) It finishes the munlock and lru putback on all pages under
their lock_page. Note that previously, lock_page covered also the
PageMlocked clearing and page isolation, but it is not needed for those
operations.
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Jörn Engel <joern@logfs.org>
Acked-by: Mel Gorman <mgorman@suse.de>
Cc: Michel Lespinasse <walken@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In munlock_vma_range(), lru_add_drain() is currently called in a loop
before each munlock_vma_page() call.
This is suboptimal for performance when munlocking many pages. The
benefits of per-cpu pagevec for batching the LRU putback are removed since
the pagevec only holds at most one page from the previous loop's
iteration.
The lru_add_drain() call also does not serve any purposes for correctness
- it does not even drain pagavecs of all cpu's. The munlock code already
expects and handles situations where a page cannot be isolated from the
LRU (e.g. because it is on some per-cpu pagevec).
The history of the (not commented) call also suggest that it appears there
as an oversight rather than intentionally. Before commit ff6a6da6 ("mm:
accelerate munlock() treatment of THP pages") the call happened only once
upon entering the function. The commit has moved the call into the while
loope. So while the other changes in the commit improved munlock
performance for THP pages, it introduced the abovementioned suboptimal
per-cpu pagevec usage.
Further in history, before commit 408e82b7 ("mm: munlock use
follow_page"), munlock_vma_pages_range() was just a wrapper around
__mlock_vma_pages_range which performed both mlock and munlock depending
on a flag. However, before ba470de4 ("mmap: handle mlocked pages during
map, remap, unmap") the function handled only mlock, not munlock. The
lru_add_drain call thus comes from the implementation in commit b291f000
("mlock: mlocked pages are unevictable" and was intended only for
mlocking, not munlocking. The original intention of draining the LRU
pagevec at mlock time was to ensure the pages were on the LRU before the
lock operation so that they could be placed on the unevictable list
immediately. There is very little motivation to do the same in the
munlock path this, particularly for every single page.
This patch therefore removes the call completely. After removing the
call, a 10% speedup was measured for munlock() of a 56GB large memory area
with THP disabled.
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Jörn Engel <joern@logfs.org>
Acked-by: Mel Gorman <mgorman@suse.de>
Cc: Michel Lespinasse <walken@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This reverts commit 1869305009 ("mm: introduce VM_POPULATE flag to
better deal with racy userspace programs").
VM_POPULATE only has any effect when userspace plays racy games with
vmas by trying to unmap and remap memory regions that mmap or mlock are
operating on.
Also, the only effect of VM_POPULATE when userspace plays such games is
that it avoids populating new memory regions that get remapped into the
address range that was being operated on by the original mmap or mlock
calls.
Let's remove VM_POPULATE as there isn't any strong argument to mandate a
new vm_flag.
Signed-off-by: Michel Lespinasse <walken@google.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
munlock_vma_pages_range() was always incrementing addresses by PAGE_SIZE
at a time. When munlocking THP pages (or the huge zero page), this
resulted in taking the mm->page_table_lock 512 times in a row.
We can do better by making use of the page_mask returned by
follow_page_mask (for the huge zero page case), or the size of the page
munlock_vma_page() operated on (for the true THP page case).
Signed-off-by: Michel Lespinasse <walken@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use long type for page counts in mm_populate() so as to avoid integer
overflow when running the following test code:
int main(void) {
void *p = mmap(NULL, 0x100000000000, PROT_READ,
MAP_PRIVATE | MAP_ANON, -1, 0);
printf("p: %p\n", p);
mlockall(MCL_CURRENT);
printf("done\n");
return 0;
}
Signed-off-by: Michel Lespinasse <walken@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The fact that mlock calls get_user_pages, and get_user_pages might call
mlock when expanding a stack looks like a potential recursion.
However, mlock makes sure the requested range is already contained
within a vma, so no stack expansion will actually happen from mlock.
Should this ever change: the stack expansion mlocks only the newly
expanded range and so will not result in recursive expansion.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Hugh Dickins <hughd@google.com>
Acked-by: Michel Lespinasse <walken@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The vm_populate() code populates user mappings without constantly
holding the mmap_sem. This makes it susceptible to racy userspace
programs: the user mappings may change while vm_populate() is running,
and in this case vm_populate() may end up populating the new mapping
instead of the old one.
In order to reduce the possibility of userspace getting surprised by
this behavior, this change introduces the VM_POPULATE vma flag which
gets set on vmas we want vm_populate() to work on. This way
vm_populate() may still end up populating the new mapping after such a
race, but only if the new mapping is also one that the user has
requested (using MAP_SHARED, MAP_LOCKED or mlock) to be populated.
Signed-off-by: Michel Lespinasse <walken@google.com>
Acked-by: Rik van Riel <riel@redhat.com>
Tested-by: Andy Lutomirski <luto@amacapital.net>
Cc: Greg Ungerer <gregungerer@westnet.com.au>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In find_extend_vma(), we don't need mlock_vma_pages_range() to verify
the vma type - we know we're working with a stack. So, we can call
directly into __mlock_vma_pages_range(), and remove the last
make_pages_present() call site.
Note that we don't use mm_populate() here, so we can't release the
mmap_sem while allocating new stack pages. This is deemed acceptable,
because the stack vmas grow by a bounded number of pages at a time, and
these are anon pages so we don't have to read from disk to populate
them.
Signed-off-by: Michel Lespinasse <walken@google.com>
Acked-by: Rik van Riel <riel@redhat.com>
Tested-by: Andy Lutomirski <luto@amacapital.net>
Cc: Greg Ungerer <gregungerer@westnet.com.au>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When creating new mappings using the MAP_POPULATE / MAP_LOCKED flags (or
with MCL_FUTURE in effect), we want to populate the pages within the
newly created vmas. This may take a while as we may have to read pages
from disk, so ideally we want to do this outside of the write-locked
mmap_sem region.
This change introduces mm_populate(), which is used to defer populating
such mappings until after the mmap_sem write lock has been released.
This is implemented as a generalization of the former do_mlock_pages(),
which accomplished the same task but was using during mlock() /
mlockall().
Signed-off-by: Michel Lespinasse <walken@google.com>
Reported-by: Andy Lutomirski <luto@amacapital.net>
Acked-by: Rik van Riel <riel@redhat.com>
Tested-by: Andy Lutomirski <luto@amacapital.net>
Cc: Greg Ungerer <gregungerer@westnet.com.au>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
With commit 8e72033f2a ("thp: make MADV_HUGEPAGE check for
mm->def_flags") the VM_NOHUGEPAGE flag may be set on s390 in
mm->def_flags for certain processes, to prevent future thp mappings.
This would be overwritten by do_mlockall(), which sets it back to 0 with
an optional VM_LOCKED flag set.
To fix this, instead of overwriting mm->def_flags in do_mlockall(), only
the VM_LOCKED flag should be set or cleared.
Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Reported-by: Vivek Goyal <vgoyal@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We had thought that pages could no longer get freed while still marked as
mlocked; but Johannes Weiner posted this program to demonstrate that
truncating an mlocked private file mapping containing COWed pages is still
mishandled:
#include <sys/types.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <stdio.h>
int main(void)
{
char *map;
int fd;
system("grep mlockfreed /proc/vmstat");
fd = open("chigurh", O_CREAT|O_EXCL|O_RDWR);
unlink("chigurh");
ftruncate(fd, 4096);
map = mmap(NULL, 4096, PROT_WRITE, MAP_PRIVATE, fd, 0);
map[0] = 11;
mlock(map, sizeof(fd));
ftruncate(fd, 0);
close(fd);
munlock(map, sizeof(fd));
munmap(map, 4096);
system("grep mlockfreed /proc/vmstat");
return 0;
}
The anon COWed pages are not caught by truncation's clear_page_mlock() of
the pagecache pages; but unmap_mapping_range() unmaps them, so we ought to
look out for them there in page_remove_rmap(). Indeed, why should
truncation or invalidation be doing the clear_page_mlock() when removing
from pagecache? mlock is a property of mapping in userspace, not a
property of pagecache: an mlocked unmapped page is nonsensical.
Reported-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Rik van Riel <riel@redhat.com>
Cc: Michel Lespinasse <walken@google.com>
Cc: Ying Han <yinghan@google.com>
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>
A long time ago, in v2.4, VM_RESERVED kept swapout process off VMA,
currently it lost original meaning but still has some effects:
| effect | alternative flags
-+------------------------+---------------------------------------------
1| account as reserved_vm | VM_IO
2| skip in core dump | VM_IO, VM_DONTDUMP
3| do not merge or expand | VM_IO, VM_DONTEXPAND, VM_HUGETLB, VM_PFNMAP
4| do not mlock | VM_IO, VM_DONTEXPAND, VM_HUGETLB, VM_PFNMAP
This patch removes reserved_vm counter from mm_struct. Seems like nobody
cares about it, it does not exported into userspace directly, it only
reduces total_vm showed in proc.
Thus VM_RESERVED can be replaced with VM_IO or pair VM_DONTEXPAND | VM_DONTDUMP.
remap_pfn_range() and io_remap_pfn_range() set VM_IO|VM_DONTEXPAND|VM_DONTDUMP.
remap_vmalloc_range() set VM_DONTEXPAND | VM_DONTDUMP.
[akpm@linux-foundation.org: drivers/vfio/pci/vfio_pci.c fixup]
Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Carsten Otte <cotte@de.ibm.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Eric Paris <eparis@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Morris <james.l.morris@oracle.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Kentaro Takeda <takedakn@nttdata.co.jp>
Cc: Matt Helsley <matthltc@us.ibm.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Venkatesh Pallipadi <venki@google.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Several users of "find_vma_prev()" were not in fact interested in the
previous vma if there was no primary vma to be found either. And in
those cases, we're much better off just using the regular "find_vma()",
and then "prev" can be looked up by just checking vma->vm_prev.
The find_vma_prev() semantics are fairly subtle (see Mikulas' recent
commit 83cd904d27: "mm: fix find_vma_prev"), and the whole "return
prev by reference" means that it generates worse code too.
Thus this "let's avoid using this inconvenient and clearly too subtle
interface when we don't really have to" patch.
Cc: Mikulas Patocka <mpatocka@redhat.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux: (230 commits)
Revert "tracing: Include module.h in define_trace.h"
irq: don't put module.h into irq.h for tracking irqgen modules.
bluetooth: macroize two small inlines to avoid module.h
ip_vs.h: fix implicit use of module_get/module_put from module.h
nf_conntrack.h: fix up fallout from implicit moduleparam.h presence
include: replace linux/module.h with "struct module" wherever possible
include: convert various register fcns to macros to avoid include chaining
crypto.h: remove unused crypto_tfm_alg_modname() inline
uwb.h: fix implicit use of asm/page.h for PAGE_SIZE
pm_runtime.h: explicitly requires notifier.h
linux/dmaengine.h: fix implicit use of bitmap.h and asm/page.h
miscdevice.h: fix up implicit use of lists and types
stop_machine.h: fix implicit use of smp.h for smp_processor_id
of: fix implicit use of errno.h in include/linux/of.h
of_platform.h: delete needless include <linux/module.h>
acpi: remove module.h include from platform/aclinux.h
miscdevice.h: delete unnecessary inclusion of module.h
device_cgroup.h: delete needless include <linux/module.h>
net: sch_generic remove redundant use of <linux/module.h>
net: inet_timewait_sock doesnt need <linux/module.h>
...
Fix up trivial conflicts (other header files, and removal of the ab3550 mfd driver) in
- drivers/media/dvb/frontends/dibx000_common.c
- drivers/media/video/{mt9m111.c,ov6650.c}
- drivers/mfd/ab3550-core.c
- include/linux/dmaengine.h
A process spent 30 minutes exiting, just munlocking the pages of a large
anonymous area that had been alternately mprotected into page-sized vmas:
for every single page there's an anon_vma walk through all the other
little vmas to find the right one.
A general fix to that would be a lot more complicated (use prio_tree on
anon_vma?), but there's one very simple thing we can do to speed up the
common case: if a page to be munlocked is mapped only once, then it is our
vma that it is mapped into, and there's no need whatever to walk through
all the others.
Okay, there is a very remote race in munlock_vma_pages_range(), if between
its follow_page() and lock_page(), another process were to munlock the
same page, then page reclaim remove it from our vma, then another process
mlock it again. We would find it with page_mapcount 1, yet it's still
mlocked in another process. But never mind, that's much less likely than
the down_read_trylock() failure which munlocking already tolerates (in
try_to_unmap_one()): in due course page reclaim will discover and move the
page to unevictable instead.
[akpm@linux-foundation.org: add comment]
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Michel Lespinasse <walken@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
MCL_FUTURE does not move pages between lru list and draining the LRU per
cpu pagevecs is a nasty activity. Avoid doing it unecessarily.
Signed-off-by: Christoph Lameter <cl@gentwo.org>
Cc: David Rientjes <rientjes@google.com>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Acked-by: Johannes Weiner <jweiner@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The files changed within are only using the EXPORT_SYMBOL
macro variants. They are not using core modular infrastructure
and hence don't need module.h but only the export.h header.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
