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2016-03-23Merge remote-tracking branch 'lsk-44/linux-linaro-lsk-v4.4' into 44rc2David Keitel
* 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>
2016-02-25mm: fix regression in remap_file_pages() emulationKirill A. Shutemov
commit 48f7df329474b49d83d0dffec1b6186647f11976 upstream. Grazvydas Ignotas has reported a regression in remap_file_pages() emulation. Testcase: #define _GNU_SOURCE #include <assert.h> #include <stdlib.h> #include <stdio.h> #include <sys/mman.h> #define SIZE (4096 * 3) int main(int argc, char **argv) { unsigned long *p; long i; p = mmap(NULL, SIZE, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, -1, 0); if (p == MAP_FAILED) { perror("mmap"); return -1; } for (i = 0; i < SIZE / 4096; i++) p[i * 4096 / sizeof(*p)] = i; if (remap_file_pages(p, 4096, 0, 1, 0)) { perror("remap_file_pages"); return -1; } if (remap_file_pages(p, 4096 * 2, 0, 1, 0)) { perror("remap_file_pages"); return -1; } assert(p[0] == 1); munmap(p, SIZE); return 0; } The second remap_file_pages() fails with -EINVAL. The reason is that remap_file_pages() emulation assumes that the target vma covers whole area we want to over map. That assumption is broken by first remap_file_pages() call: it split the area into two vma. The solution is to check next adjacent vmas, if they map the same file with the same flags. Fixes: c8d78c1823f4 ("mm: replace remap_file_pages() syscall with emulation") Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Reported-by: Grazvydas Ignotas <notasas@gmail.com> Tested-by: Grazvydas Ignotas <notasas@gmail.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>
2016-02-25mm: replace vma_lock_anon_vma with anon_vma_lock_read/writeKonstantin Khlebnikov
commit 12352d3cae2cebe18805a91fab34b534d7444231 upstream. Sequence vma_lock_anon_vma() - vma_unlock_anon_vma() isn't safe if anon_vma appeared between lock and unlock. We have to check anon_vma first or call anon_vma_prepare() to be sure that it's here. There are only few users of these legacy helpers. Let's get rid of them. This patch fixes anon_vma lock imbalance in validate_mm(). Write lock isn't required here, read lock is enough. And reorders expand_downwards/expand_upwards: security_mmap_addr() and wrapping-around check don't have to be under anon vma lock. Link: https://lkml.kernel.org/r/CACT4Y+Y908EjM2z=706dv4rV6dWtxTLK9nFg9_7DhRMLppBo2g@mail.gmail.com Signed-off-by: Konstantin Khlebnikov <koct9i@gmail.com> Reported-by: Dmitry Vyukov <dvyukov@google.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Andrea Arcangeli <aarcange@redhat.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>
2016-02-16FROMLIST: mm: mmap: Add new /proc tunable for mmap_base ASLR.dcashman
(cherry picked from commit https://lkml.org/lkml/2015/12/21/337) ASLR only uses as few as 8 bits to generate the random offset for the mmap base address on 32 bit architectures. This value was chosen to prevent a poorly chosen value from dividing the address space in such a way as to prevent large allocations. This may not be an issue on all platforms. Allow the specification of a minimum number of bits so that platforms desiring greater ASLR protection may determine where to place the trade-off. Bug: 24047224 Signed-off-by: Daniel Cashman <dcashman@android.com> Signed-off-by: Daniel Cashman <dcashman@google.com> Change-Id: Ibf9ed3d4390e9686f5cc34f605d509a20d40e6c2
2016-02-16mm: add a field to store names for private anonymous memoryColin Cross
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>
2015-11-05mm: introduce VM_LOCKONFAULTEric B Munson
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>
2015-11-05mm/mmap.c: change __install_special_mapping() args orderChen Gang
Make __install_special_mapping() args order match the caller, so the caller can pass their register args directly to callee with no touch. For most of architectures, args (at least the first 5th args) are in registers, so this change will have effect on most of architectures. For -O2, __install_special_mapping() may be inlined under most of architectures, but for -Os, it should not. So this change can get a little better performance for -Os, at least. Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-05mm/mmap.c: do not initialize retval in mmap_pgoff()Chen Gang
When fget() fails we can return -EBADF directly. Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com> Acked-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-05mm/mmap.c: remove redundant statement "error = -ENOMEM"Chen Gang
It is still a little better to remove it, although it should be skipped by "-O2". Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>=0A= Acked-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-05mm: add the "struct mm_struct *mm" local intoOleg Nesterov
Cosmetic, but expand_upwards() and expand_downwards() overuse vma->vm_mm, a local variable makes sense imho. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Hugh Dickins <hughd@google.com> Cc: Andrey Konovalov <andreyknvl@google.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: "Kirill A. Shutemov" <kirill@shutemov.name> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-05mm: fix the racy mm->locked_vm change inOleg Nesterov
"mm->locked_vm += grow" and vm_stat_account() in acct_stack_growth() are not safe; multiple threads using the same ->mm can do this at the same time trying to expans different vma's under down_read(mmap_sem). This means that one of the "locked_vm += grow" changes can be lost and we can miss munlock_vma_pages_all() later. Move this code into the caller(s) under mm->page_table_lock. All other updates to ->locked_vm hold mmap_sem for writing. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Hugh Dickins <hughd@google.com> Cc: Andrey Konovalov <andreyknvl@google.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: "Kirill A. Shutemov" <kirill@shutemov.name> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-05mm/mmap: use offset_in_page macroAlexander Kuleshov
linux/mm.h provides offset_in_page() macro. Let's use already predefined macro instead of (addr & ~PAGE_MASK). Signed-off-by: Alexander Kuleshov <kuleshovmail@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-05mm/mmap.c: remove useless statement "vma = NULL" in find_vma()Chen Gang
Before the main loop, vma is already is NULL. There is no need to set it to NULL again. Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-22mm, dax: VMA with vm_ops->pfn_mkwrite wants to be write-notifiedKirill A. Shutemov
For VM_PFNMAP and VM_MIXEDMAP we use vm_ops->pfn_mkwrite instead of vm_ops->page_mkwrite to notify abort write access. This means we want vma->vm_page_prot to be write-protected if the VMA provides this vm_ops. A theoretical scenario that will cause these missed events is: On writable mapping with vm_ops->pfn_mkwrite, but without vm_ops->page_mkwrite: read fault followed by write access to the pfn. Writable pte will be set up on read fault and write fault will not be generated. I found it examining Dave's complaint on generic/080: http://lkml.kernel.org/g/20150831233803.GO3902@dastard Although I don't think it's the reason. It shouldn't be a problem for ext2/ext4 as they provide both pfn_mkwrite and page_mkwrite. [akpm@linux-foundation.org: add local vm_ops to avoid 80-cols mess] Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Yigal Korman <yigal@plexistor.com> Acked-by: Boaz Harrosh <boaz@plexistor.com> Cc: Matthew Wilcox <matthew.r.wilcox@intel.com> Cc: Jan Kara <jack@suse.cz> Cc: Dave Chinner <david@fromorbit.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-17revert "mm: make sure all file VMAs have ->vm_ops set"Andrew Morton
Revert commit 6dc296e7df4c "mm: make sure all file VMAs have ->vm_ops set". Will Deacon reports that it "causes some mmap regressions in LTP, which appears to use a MAP_PRIVATE mmap of /dev/zero as a way to get anonymous pages in some of its tests (specifically mmap10 [1])". William Shuman reports Oracle crashes. So revert the patch while we work out what to do. Reported-by: William Shuman <wshuman3@gmail.com> Reported-by: Will Deacon <will.deacon@arm.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-10mm: make sure all file VMAs have ->vm_ops setKirill A. Shutemov
We rely on vma->vm_ops == NULL to detect anonymous VMA: see vma_is_anonymous(), but some drivers doesn't set ->vm_ops. As a result we can end up with anonymous page in private file mapping. That should not lead to serious misbehaviour, but nevertheless is wrong. Let's fix by setting up dummy ->vm_ops for file mmapping if f_op->mmap() didn't set its own. The patch also adds sanity check into __vma_link_rb(). It will help catch broken VMAs which inserted directly into mm_struct via insert_vm_struct(). Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Minchan Kim <minchan@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-10mm, mpx: add "vm_flags_t vm_flags" arg to do_mmap_pgoff()Oleg Nesterov
Add the additional "vm_flags_t vm_flags" argument to do_mmap_pgoff(), rename it to do_mmap(), and re-introduce do_mmap_pgoff() as a simple wrapper on top of do_mmap(). Perhaps we should update the callers of do_mmap_pgoff() and kill it later. This way mpx_mmap() can simply call do_mmap(vm_flags => VM_MPX) and do not play with vm internals. After this change mmap_region() has a single user outside of mmap.c, arch/tile/mm/elf.c:arch_setup_additional_pages(). It would be nice to change arch/tile/ and unexport mmap_region(). [kirill@shutemov.name: fix build] [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Dave Hansen <dave.hansen@linux.intel.com> Tested-by: Dave Hansen <dave.hansen@linux.intel.com> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Ingo Molnar <mingo@elte.hu> Cc: Minchan Kim <minchan@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-08mm/mmap.c:insert_vm_struct(): check for failure before setting valuesChen Gang
There's no point in initializing vma->vm_pgoff if the insertion attempt will be failing anyway. Run the checks before performing the initialization. Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com> Cc: Michal Hocko <mhocko@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-08mm/mmap.c: simplify the failure return working flowChen Gang
__split_vma() doesn't need out_err label, neither need initializing err. copy_vma() can return NULL directly when kmem_cache_alloc() fails. Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-08mremap: fix the wrong !vma->vm_file check in copy_vma()Oleg Nesterov
Test-case: #define _GNU_SOURCE #include <stdio.h> #include <unistd.h> #include <stdlib.h> #include <string.h> #include <sys/mman.h> #include <assert.h> void *find_vdso_vaddr(void) { FILE *perl; char buf[32] = {}; perl = popen("perl -e 'open STDIN,qq|/proc/@{[getppid]}/maps|;" "/^(.*?)-.*vdso/ && print hex $1 while <>'", "r"); fread(buf, sizeof(buf), 1, perl); fclose(perl); return (void *)atol(buf); } #define PAGE_SIZE 4096 void *get_unmapped_area(void) { void *p = mmap(0, PAGE_SIZE, PROT_NONE, MAP_PRIVATE|MAP_ANONYMOUS, -1,0); assert(p != MAP_FAILED); munmap(p, PAGE_SIZE); return p; } char save[2][PAGE_SIZE]; int main(void) { void *vdso = find_vdso_vaddr(); void *page[2]; assert(vdso); memcpy(save, vdso, sizeof (save)); // force another fault on the next check assert(madvise(vdso, 2 * PAGE_SIZE, MADV_DONTNEED) == 0); page[0] = mremap(vdso, PAGE_SIZE, PAGE_SIZE, MREMAP_FIXED | MREMAP_MAYMOVE, get_unmapped_area()); page[1] = mremap(vdso + PAGE_SIZE, PAGE_SIZE, PAGE_SIZE, MREMAP_FIXED | MREMAP_MAYMOVE, get_unmapped_area()); assert(page[0] != MAP_FAILED && page[1] != MAP_FAILED); printf("match: %d %d\n", !memcmp(save[0], page[0], PAGE_SIZE), !memcmp(save[1], page[1], PAGE_SIZE)); return 0; } fails without this patch. Before the previous commit it gets the wrong page, now it segfaults (which is imho better). This is because copy_vma() wrongly assumes that if vma->vm_file == NULL is irrelevant until the first fault which will use do_anonymous_page(). This is obviously wrong for the special mapping. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Hugh Dickins <hughd@google.com> Cc: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-08mmap: fix the usage of ->vm_pgoff in special_mapping pathsOleg Nesterov
Test-case: #include <stdio.h> #include <unistd.h> #include <stdlib.h> #include <string.h> #include <sys/mman.h> #include <assert.h> void *find_vdso_vaddr(void) { FILE *perl; char buf[32] = {}; perl = popen("perl -e 'open STDIN,qq|/proc/@{[getppid]}/maps|;" "/^(.*?)-.*vdso/ && print hex $1 while <>'", "r"); fread(buf, sizeof(buf), 1, perl); fclose(perl); return (void *)atol(buf); } #define PAGE_SIZE 4096 int main(void) { void *vdso = find_vdso_vaddr(); assert(vdso); // of course they should differ, and they do so far printf("vdso pages differ: %d\n", !!memcmp(vdso, vdso + PAGE_SIZE, PAGE_SIZE)); // split into 2 vma's assert(mprotect(vdso, PAGE_SIZE, PROT_READ) == 0); // force another fault on the next check assert(madvise(vdso, 2 * PAGE_SIZE, MADV_DONTNEED) == 0); // now they no longer differ, the 2nd vm_pgoff is wrong printf("vdso pages differ: %d\n", !!memcmp(vdso, vdso + PAGE_SIZE, PAGE_SIZE)); return 0; } Output: vdso pages differ: 1 vdso pages differ: 0 This is because split_vma() correctly updates ->vm_pgoff, but the logic in insert_vm_struct() and special_mapping_fault() is absolutely broken, so the fault at vdso + PAGE_SIZE return the 1st page. The same happens if you simply unmap the 1st page. special_mapping_fault() does: pgoff = vmf->pgoff - vma->vm_pgoff; and this is _only_ correct if vma->vm_start mmaps the first page from ->vm_private_data array. vdso or any other user of install_special_mapping() is not anonymous, it has the "backing storage" even if it is just the array of pages. So we actually need to make vm_pgoff work as an offset in this array. Note: this also allows to fix another problem: currently gdb can't access "[vvar]" memory because in this case special_mapping_fault() doesn't work. Now that we can use ->vm_pgoff we can implement ->access() and fix this. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Hugh Dickins <hughd@google.com> Cc: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-04userfaultfd: teach vma_merge to merge across vma->vm_userfaultfd_ctxAndrea Arcangeli
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>
2015-07-10vfs: Commit to never having exectuables on proc and sysfs.Eric W. Biederman
Today proc and sysfs do not contain any executable files. Several applications today mount proc or sysfs without noexec and nosuid and then depend on there being no exectuables files on proc or sysfs. Having any executable files show on proc or sysfs would cause a user space visible regression, and most likely security problems. Therefore commit to never allowing executables on proc and sysfs by adding a new flag to mark them as filesystems without executables and enforce that flag. Test the flag where MNT_NOEXEC is tested today, so that the only user visible effect will be that exectuables will be treated as if the execute bit is cleared. The filesystems proc and sysfs do not currently incoporate any executable files so this does not result in any user visible effects. This makes it unnecessary to vet changes to proc and sysfs tightly for adding exectuable files or changes to chattr that would modify existing files, as no matter what the individual file say they will not be treated as exectuable files by the vfs. Not having to vet changes to closely is important as without this we are only one proc_create call (or another goof up in the implementation of notify_change) from having problematic executables on proc. Those mistakes are all too easy to make and would create a situation where there are security issues or the assumptions of some program having to be broken (and cause userspace regressions). Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-06-24mm/mmap.c: optimization of do_mmap_pgoff functionPiotr Kwapulinski
The simple check for zero length memory mapping may be performed earlier. So that in case of zero length memory mapping some unnecessary code is not executed at all. It does not make the code less readable and saves some CPU cycles. Signed-off-by: Piotr Kwapulinski <kwapulinski.piotr@gmail.com> Acked-by: Michal Hocko <mhocko@suse.cz> Acked-by: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-15mm/mmap.c: use while instead of if+gotoRasmus Villemoes
The creators of the C language gave us the while keyword. Let's use that instead of synthesizing it from if+goto. Made possible by 6597d783397a ("mm/mmap.c: replace find_vma_prepare() with clearer find_vma_links()"). [akpm@linux-foundation.org: fix 80-col overflows] Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Roman Gushchin <klamm@yandex-team.ru> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-15mm: remove rest of ACCESS_ONCE() usagesJason Low
We converted some of the usages of ACCESS_ONCE to READ_ONCE in the mm/ tree since it doesn't work reliably on non-scalar types. This patch removes the rest of the usages of ACCESS_ONCE, and use the new READ_ONCE API for the read accesses. This makes things cleaner, instead of using separate/multiple sets of APIs. Signed-off-by: Jason Low <jason.low2@hp.com> Acked-by: Michal Hocko <mhocko@suse.cz> Acked-by: Davidlohr Bueso <dave@stgolabs.net> Acked-by: Rik van Riel <riel@redhat.com> Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14mm: rename __mlock_vma_pages_range() to populate_vma_page_range()Kirill A. Shutemov
__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 cea10a19b797 ("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>
2015-03-25mm: fix anon_vma->degree underflow in anon_vma endless growing preventionLeon Yu
I have constantly stumbled upon "kernel BUG at mm/rmap.c:399!" after upgrading to 3.19 and had no luck with 4.0-rc1 neither. So, after looking into new logic introduced by commit 7a3ef208e662 ("mm: prevent endless growth of anon_vma hierarchy"), I found chances are that unlink_anon_vmas() is called without incrementing dst->anon_vma->degree in anon_vma_clone() due to allocation failure. If dst->anon_vma is not NULL in error path, its degree will be incorrectly decremented in unlink_anon_vmas() and eventually underflow when exiting as a result of another call to unlink_anon_vmas(). That's how "kernel BUG at mm/rmap.c:399!" is triggered for me. This patch fixes the underflow by dropping dst->anon_vma when allocation fails. It's safe to do so regardless of original value of dst->anon_vma because dst->anon_vma doesn't have valid meaning if anon_vma_clone() fails. Besides, callers don't care dst->anon_vma in such case neither. Also suggested by Michal Hocko, we can clean up vma_adjust() a bit as anon_vma_clone() now does the work. [akpm@linux-foundation.org: tweak comment] Fixes: 7a3ef208e662 ("mm: prevent endless growth of anon_vma hierarchy") Signed-off-by: Leon Yu <chianglungyu@gmail.com> Signed-off-by: Konstantin Khlebnikov <koct9i@gmail.com> Reviewed-by: Michal Hocko <mhocko@suse.cz> Acked-by: Rik van Riel <riel@redhat.com> Acked-by: David Rientjes <rientjes@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>
2015-02-11mm/mmap.c: fix arithmetic overflow in __vm_enough_memory()Roman Gushchin
I noticed, that "allowed" can easily overflow by falling below 0, because (total_vm / 32) can be larger than "allowed". The problem occurs in OVERCOMMIT_NONE mode. In this case, a huge allocation can success and overcommit the system (despite OVERCOMMIT_NONE mode). All subsequent allocations will fall (system-wide), so system become unusable. The problem was masked out by commit c9b1d0981fcc ("mm: limit growth of 3% hardcoded other user reserve"), but it's easy to reproduce it on older kernels: 1) set overcommit_memory sysctl to 2 2) mmap() large file multiple times (with VM_SHARED flag) 3) try to malloc() large amount of memory It also can be reproduced on newer kernels, but miss-configured sysctl_user_reserve_kbytes is required. Fix this issue by switching to signed arithmetic here. [akpm@linux-foundation.org: use min_t] Signed-off-by: Roman Gushchin <klamm@yandex-team.ru> Cc: Andrew Shewmaker <agshew@gmail.com> Cc: Rik van Riel <riel@redhat.com> Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Reviewed-by: Michal Hocko <mhocko@suse.cz> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-11mm: fix false-positive warning on exit due mm_nr_pmds(mm)Kirill A. Shutemov
The problem is that we check nr_ptes/nr_pmds in exit_mmap() which happens *before* pgd_free(). And if an arch does pte/pmd allocation in pgd_alloc() and frees them in pgd_free() we see offset in counters by the time of the checks. We tried to workaround this by offsetting expected counter value according to FIRST_USER_ADDRESS for both nr_pte and nr_pmd in exit_mmap(). But it doesn't work in some cases: 1. ARM with LPAE enabled also has non-zero USER_PGTABLES_CEILING, but upper addresses occupied with huge pmd entries, so the trick with offsetting expected counter value will get really ugly: we will have to apply it nr_pmds, but not nr_ptes. 2. Metag has non-zero FIRST_USER_ADDRESS, but doesn't do allocation pte/pmd page tables allocation in pgd_alloc(), just setup a pgd entry which is allocated at boot and shared accross all processes. The proposal is to move the check to check_mm() which happens *after* pgd_free() and do proper accounting during pgd_alloc() and pgd_free() which would bring counters to zero if nothing leaked. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Reported-by: Tyler Baker <tyler.baker@linaro.org> Tested-by: Tyler Baker <tyler.baker@linaro.org> Tested-by: Nishanth Menon <nm@ti.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: James Hogan <james.hogan@imgtec.com> Cc: Guan Xuetao <gxt@mprc.pku.edu.cn> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-11mm: account pmd page tables to the processKirill A. Shutemov
Dave noticed that unprivileged process can allocate significant amount of memory -- >500 MiB on x86_64 -- and stay unnoticed by oom-killer and memory cgroup. The trick is to allocate a lot of PMD page tables. Linux kernel doesn't account PMD tables to the process, only PTE. The use-cases below use few tricks to allocate a lot of PMD page tables while keeping VmRSS and VmPTE low. oom_score for the process will be 0. #include <errno.h> #include <stdio.h> #include <stdlib.h> #include <unistd.h> #include <sys/mman.h> #include <sys/prctl.h> #define PUD_SIZE (1UL << 30) #define PMD_SIZE (1UL << 21) #define NR_PUD 130000 int main(void) { char *addr = NULL; unsigned long i; prctl(PR_SET_THP_DISABLE); for (i = 0; i < NR_PUD ; i++) { addr = mmap(addr + PUD_SIZE, PUD_SIZE, PROT_WRITE|PROT_READ, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0); if (addr == MAP_FAILED) { perror("mmap"); break; } *addr = 'x'; munmap(addr, PMD_SIZE); mmap(addr, PMD_SIZE, PROT_WRITE|PROT_READ, MAP_ANONYMOUS|MAP_PRIVATE|MAP_FIXED, -1, 0); if (addr == MAP_FAILED) perror("re-mmap"), exit(1); } printf("PID %d consumed %lu KiB in PMD page tables\n", getpid(), i * 4096 >> 10); return pause(); } The patch addresses the issue by account PMD tables to the process the same way we account PTE. The main place where PMD tables is accounted is __pmd_alloc() and free_pmd_range(). But there're few corner cases: - HugeTLB can share PMD page tables. The patch handles by accounting the table to all processes who share it. - x86 PAE pre-allocates few PMD tables on fork. - Architectures with FIRST_USER_ADDRESS > 0. We need to adjust sanity check on exit(2). Accounting only happens on configuration where PMD page table's level is present (PMD is not folded). As with nr_ptes we use per-mm counter. The counter value is used to calculate baseline for badness score by oom-killer. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Reported-by: Dave Hansen <dave.hansen@linux.intel.com> Cc: Hugh Dickins <hughd@google.com> Reviewed-by: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Pavel Emelyanov <xemul@openvz.org> Cc: David Rientjes <rientjes@google.com> Tested-by: Sedat Dilek <sedat.dilek@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-10rmap: drop support of non-linear mappingsKirill A. Shutemov
We don't create non-linear mappings anymore. Let's drop code which handles them in rmap. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-10mm: replace remap_file_pages() syscall with emulationKirill A. Shutemov
remap_file_pages(2) was invented to be able efficiently map parts of huge file into limited 32-bit virtual address space such as in database workloads. Nonlinear mappings are pain to support and it seems there's no legitimate use-cases nowadays since 64-bit systems are widely available. Let's drop it and get rid of all these special-cased code. The patch replaces the syscall with emulation which creates new VMA on each remap_file_pages(), unless they it can be merged with an adjacent one. I didn't find *any* real code that uses remap_file_pages(2) to test emulation impact on. I've checked Debian code search and source of all packages in ALT Linux. No real users: libc wrappers, mentions in strace, gdb, valgrind and this kind of stuff. There are few basic tests in LTP for the syscall. They work just fine with emulation. To test performance impact, I've written small test case which demonstrate pretty much worst case scenario: map 4G shmfs file, write to begin of every page pgoff of the page, remap pages in reverse order, read every page. The test creates 1 million of VMAs if emulation is in use, so I had to set vm.max_map_count to 1100000 to avoid -ENOMEM. Before: 23.3 ( +- 4.31% ) seconds After: 43.9 ( +- 0.85% ) seconds Slowdown: 1.88x I believe we can live with that. Test case: #define _GNU_SOURCE #include <assert.h> #include <stdlib.h> #include <stdio.h> #include <sys/mman.h> #define MB (1024UL * 1024) #define SIZE (4096 * MB) int main(int argc, char **argv) { unsigned long *p; long i, pass; for (pass = 0; pass < 10; pass++) { p = mmap(NULL, SIZE, PROT_READ|PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, -1, 0); if (p == MAP_FAILED) { perror("mmap"); return -1; } for (i = 0; i < SIZE / 4096; i++) p[i * 4096 / sizeof(*p)] = i; for (i = 0; i < SIZE / 4096; i++) { if (remap_file_pages(p + i * 4096 / sizeof(*p), 4096, 0, (SIZE - 4096 * (i + 1)) >> 12, 0)) { perror("remap_file_pages"); return -1; } } for (i = SIZE / 4096 - 1; i >= 0; i--) assert(p[i * 4096 / sizeof(*p)] == SIZE / 4096 - i - 1); munmap(p, SIZE); } return 0; } [akpm@linux-foundation.org: fix spello] [sasha.levin@oracle.com: initialize populate before usage] [sasha.levin@oracle.com: grab file ref to prevent race while mmaping] Signed-off-by: "Kirill A. Shutemov" <kirill@shutemov.name> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Dave Jones <davej@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Armin Rigo <arigo@tunes.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-01-11mm: fix corner case in anon_vma endless growing preventionKonstantin Khlebnikov
Fix for BUG_ON(anon_vma->degree) splashes in unlink_anon_vmas() ("kernel BUG at mm/rmap.c:399!") caused by commit 7a3ef208e662 ("mm: prevent endless growth of anon_vma hierarchy") Anon_vma_clone() is usually called for a copy of source vma in destination argument. If source vma has anon_vma it should be already in dst->anon_vma. NULL in dst->anon_vma is used as a sign that it's called from anon_vma_fork(). In this case anon_vma_clone() finds anon_vma for reusing. Vma_adjust() calls it differently and this breaks anon_vma reusing logic: anon_vma_clone() links vma to old anon_vma and updates degree counters but vma_adjust() overrides vma->anon_vma right after that. As a result final unlink_anon_vmas() decrements degree for wrong anon_vma. This patch assigns ->anon_vma before calling anon_vma_clone(). Signed-off-by: Konstantin Khlebnikov <koct9i@gmail.com> Reported-and-tested-by: Chris Clayton <chris2553@googlemail.com> Reported-and-tested-by: Oded Gabbay <oded.gabbay@amd.com> Reported-and-tested-by: Chih-Wei Huang <cwhuang@android-x86.org> Acked-by: Rik van Riel <riel@redhat.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Daniel Forrest <dan.forrest@ssec.wisc.edu> Cc: Michal Hocko <mhocko@suse.cz> Cc: stable@vger.kernel.org # to match back-porting of 7a3ef208e662 Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-01-11mm: Don't count the stack guard page towards RLIMIT_STACKLinus Torvalds
Commit fee7e49d4514 ("mm: propagate error from stack expansion even for guard page") made sure that we return the error properly for stack growth conditions. It also theorized that counting the guard page towards the stack limit might break something, but also said "Let's see if anybody notices". Somebody did notice. Apparently android-x86 sets the stack limit very close to the limit indeed, and including the guard page in the rlimit check causes the android 'zygote' process problems. So this adds the (fairly trivial) code to make the stack rlimit check be against the actual real stack size, rather than the size of the vma that includes the guard page. Reported-and-tested-by: Chih-Wei Huang <cwhuang@android-x86.org> Cc: Jay Foad <jay.foad@gmail.com> Cc: stable@kernel.org # to match back-porting of fee7e49d4514 Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-12-13mm: export find_extend_vma() and handle_mm_fault() for driver useJesse Barnes
This lets drivers like the AMD IOMMUv2 driver handle faults a bit more simply, rather than doing tricks with page refs and get_user_pages(). Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org> Cc: Oded Gabbay <oded.gabbay@amd.com> Cc: Joerg Roedel <jroedel@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-12-13mm: convert i_mmap_mutex to rwsemDavidlohr Bueso
The i_mmap_mutex is a close cousin of the anon vma lock, both protecting similar data, one for file backed pages and the other for anon memory. To this end, this lock can also be a rwsem. In addition, there are some important opportunities to share the lock when there are no tree modifications. This conversion is straightforward. For now, all users take the write lock. [sfr@canb.auug.org.au: update fremap.c] Signed-off-by: Davidlohr Bueso <dbueso@suse.de> Reviewed-by: Rik van Riel <riel@redhat.com> Acked-by: "Kirill A. Shutemov" <kirill@shutemov.name> Acked-by: Hugh Dickins <hughd@google.com> Cc: Oleg Nesterov <oleg@redhat.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Acked-by: Mel Gorman <mgorman@suse.de> Signed-off-by: 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>
2014-12-13mm: use new helper functions around the i_mmap_mutexDavidlohr Bueso
Convert all open coded mutex_lock/unlock calls to the i_mmap_[lock/unlock]_write() helpers. Signed-off-by: Davidlohr Bueso <dbueso@suse.de> Acked-by: Rik van Riel <riel@redhat.com> Acked-by: "Kirill A. Shutemov" <kirill@shutemov.name> Acked-by: Hugh Dickins <hughd@google.com> Cc: Oleg Nesterov <oleg@redhat.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Acked-by: Mel Gorman <mgorman@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-12-10Merge branch 'x86-mpx-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 MPX support from Thomas Gleixner: "This enables support for x86 MPX. MPX is a new debug feature for bound checking in user space. It requires kernel support to handle the bound tables and decode the bound violating instruction in the trap handler" * 'x86-mpx-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: asm-generic: Remove asm-generic arch_bprm_mm_init() mm: Make arch_unmap()/bprm_mm_init() available to all architectures x86: Cleanly separate use of asm-generic/mm_hooks.h x86 mpx: Change return type of get_reg_offset() fs: Do not include mpx.h in exec.c x86, mpx: Add documentation on Intel MPX x86, mpx: Cleanup unused bound tables x86, mpx: On-demand kernel allocation of bounds tables x86, mpx: Decode MPX instruction to get bound violation information x86, mpx: Add MPX-specific mmap interface x86, mpx: Introduce VM_MPX to indicate that a VMA is MPX specific x86, mpx: Add MPX to disabled features ia64: Sync struct siginfo with general version mips: Sync struct siginfo with general version mpx: Extend siginfo structure to include bound violation information x86, mpx: Rename cfg_reg_u and status_reg x86: mpx: Give bndX registers actual names x86: Remove arbitrary instruction size limit in instruction decoder
2014-12-03mm: fix anon_vma_clone() error treatmentDaniel Forrest
Andrew Morton noticed that the error return from anon_vma_clone() was being dropped and replaced with -ENOMEM (which is not itself a bug because the only error return value from anon_vma_clone() is -ENOMEM). I did an audit of callers of anon_vma_clone() and discovered an actual bug where the error return was being lost. In __split_vma(), between Linux 3.11 and 3.12 the code was changed so the err variable is used before the call to anon_vma_clone() and the default initial value of -ENOMEM is overwritten. So a failure of anon_vma_clone() will return success since err at this point is now zero. Below is a patch which fixes this bug and also propagates the error return value from anon_vma_clone() in all cases. Fixes: ef0855d334e1 ("mm: mempolicy: turn vma_set_policy() into vma_dup_policy()") Signed-off-by: Daniel Forrest <dan.forrest@ssec.wisc.edu> Reviewed-by: Michal Hocko <mhocko@suse.cz> Cc: Konstantin Khlebnikov <koct9i@gmail.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Rik van Riel <riel@redhat.com> Cc: Tim Hartrick <tim@edgecast.com> Cc: Hugh Dickins <hughd@google.com> Cc: Michel Lespinasse <walken@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: <stable@vger.kernel.org> [3.12+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-11-18x86, mpx: Cleanup unused bound tablesDave Hansen
The previous patch allocates bounds tables on-demand. As noted in an earlier description, these can add up to *HUGE* amounts of memory. This has caused OOMs in practice when running tests. This patch adds support for freeing bounds tables when they are no longer in use. There are two types of mappings in play when unmapping tables: 1. The mapping with the actual data, which userspace is munmap()ing or brk()ing away, etc... 2. The mapping for the bounds table *backing* the data (is tagged with VM_MPX, see the patch "add MPX specific mmap interface"). If userspace use the prctl() indroduced earlier in this patchset to enable the management of bounds tables in kernel, when it unmaps the first type of mapping with the actual data, the kernel needs to free the mapping for the bounds table backing the data. This patch hooks in at the very end of do_unmap() to do so. We look at the addresses being unmapped and find the bounds directory entries and tables which cover those addresses. If an entire table is unused, we clear associated directory entry and free the table. Once we unmap the bounds table, we would have a bounds directory entry pointing at empty address space. That address space might now be allocated for some other (random) use, and the MPX hardware might now try to walk it as if it were a bounds table. That would be bad. So any unmapping of an enture bounds table has to be accompanied by a corresponding write to the bounds directory entry to invalidate it. That write to the bounds directory can fault, which causes the following problem: Since we are doing the freeing from munmap() (and other paths like it), we hold mmap_sem for write. If we fault, the page fault handler will attempt to acquire mmap_sem for read and we will deadlock. To avoid the deadlock, we pagefault_disable() when touching the bounds directory entry and use a get_user_pages() to resolve the fault. The unmapping of bounds tables happends under vm_munmap(). We also (indirectly) call vm_munmap() to _do_ the unmapping of the bounds tables. We avoid unbounded recursion by disallowing freeing of bounds tables *for* bounds tables. This would not occur normally, so should not have any practical impact. Being strict about it here helps ensure that we do not have an exploitable stack overflow. Based-on-patch-by: Qiaowei Ren <qiaowei.ren@intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Cc: linux-mm@kvack.org Cc: linux-mips@linux-mips.org Cc: Dave Hansen <dave@sr71.net> Link: http://lkml.kernel.org/r/20141114151831.E4531C4A@viggo.jf.intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-10-29mm, thp: fix collapsing of hugepages on madviseDavid Rientjes
If an anonymous mapping is not allowed to fault thp memory and then madvise(MADV_HUGEPAGE) is used after fault, khugepaged will never collapse this memory into thp memory. This occurs because the madvise(2) handler for thp, hugepage_madvise(), clears VM_NOHUGEPAGE on the stack and it isn't stored in vma->vm_flags until the final action of madvise_behavior(). This causes the khugepaged_enter_vma_merge() to be a no-op in hugepage_madvise() when the vma had previously had VM_NOHUGEPAGE set. Fix this by passing the correct vma flags to the khugepaged mm slot handler. There's no chance khugepaged can run on this vma until after madvise_behavior() returns since we hold mm->mmap_sem. It would be possible to clear VM_NOHUGEPAGE directly from vma->vm_flags in hugepage_advise(), but I didn't want to introduce special case behavior into madvise_behavior(). I think it's best to just let it always set vma->vm_flags itself. Signed-off-by: David Rientjes <rientjes@google.com> Reported-by: Suleiman Souhlal <suleiman@google.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-10-14mm: softdirty: enable write notifications on VMAs after VM_SOFTDIRTY clearedPeter Feiner
For VMAs that don't want write notifications, PTEs created for read faults have their write bit set. If the read fault happens after VM_SOFTDIRTY is cleared, then the PTE's softdirty bit will remain clear after subsequent writes. Here's a simple code snippet to demonstrate the bug: char* m = mmap(NULL, getpagesize(), PROT_READ | PROT_WRITE, MAP_ANONYMOUS | MAP_SHARED, -1, 0); system("echo 4 > /proc/$PPID/clear_refs"); /* clear VM_SOFTDIRTY */ assert(*m == '\0'); /* new PTE allows write access */ assert(!soft_dirty(x)); *m = 'x'; /* should dirty the page */ assert(soft_dirty(x)); /* fails */ With this patch, write notifications are enabled when VM_SOFTDIRTY is cleared. Furthermore, to avoid unnecessary faults, write notifications are disabled when VM_SOFTDIRTY is set. As a side effect of enabling and disabling write notifications with care, this patch fixes a bug in mprotect where vm_page_prot bits set by drivers were zapped on mprotect. An analogous bug was fixed in mmap by commit c9d0bf241451 ("mm: uncached vma support with writenotify"). Signed-off-by: Peter Feiner <pfeiner@google.com> Reported-by: Peter Feiner <pfeiner@google.com> Suggested-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Pavel Emelyanov <xemul@parallels.com> Cc: Jamie Liu <jamieliu@google.com> Cc: Hugh Dickins <hughd@google.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-10-10Merge branch 'for-3.18' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu 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 6ae833c7fe0c ("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 ...
2014-10-09mm: use VM_BUG_ON_MM where possibleSasha Levin
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>
2014-10-09mm/mmap.c: clean up CONFIG_DEBUG_VM_RB checksAndrew Morton
- be consistent in printing the test which failed - one message was actually wrong (a<b != b>a) - don't print second bogus warning if browse_rb() failed Cc: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-10-09mm: convert a few VM_BUG_ON callers to VM_BUG_ON_VMASasha Levin
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>
2014-10-09mm: use may_adjust_brk helperCyrill Gorcunov
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Kees Cook <keescook@chromium.org> Cc: Tejun Heo <tj@kernel.org> Cc: Andrew Vagin <avagin@openvz.org> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: H. Peter Anvin <hpa@zytor.com> Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Cc: Pavel Emelyanov <xemul@parallels.com> Cc: Vasiliy Kulikov <segoon@openwall.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Michael Kerrisk <mtk.manpages@gmail.com> Cc: Julien Tinnes <jln@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-10-09mm/mmap.c: whitespace fixesvishnu.ps
Signed-off-by: vishnu.ps <vishnu.ps@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-09-24Merge branch 'for-linus' of ↵Tejun Heo
git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux-block into for-3.18 This is to receive 0a30288da1ae ("blk-mq, percpu_ref: implement a kludge for SCSI blk-mq stall during probe") which implements __percpu_ref_kill_expedited() to work around SCSI blk-mq stall. The commit reverted and patches to implement proper fix will be added. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Kent Overstreet <kmo@daterainc.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Christoph Hellwig <hch@lst.de>
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