summaryrefslogtreecommitdiff
path: root/mm/page_ext.c (follow)
Commit message (Collapse)AuthorAge
* Merge android-4.4.179 (aab9adb) into msm-4.4Srinivasarao P2019-05-02
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * refs/heads/tmp-aab9adb Linux 4.4.179 kernel/sysctl.c: fix out-of-bounds access when setting file-max Revert "locking/lockdep: Add debug_locks check in __lock_downgrade()" ALSA: info: Fix racy addition/deletion of nodes mm/vmstat.c: fix /proc/vmstat format for CONFIG_DEBUG_TLBFLUSH=y CONFIG_SMP=n device_cgroup: fix RCU imbalance in error case sched/fair: Limit sched_cfs_period_timer() loop to avoid hard lockup Revert "kbuild: use -Oz instead of -Os when using clang" mac80211: do not call driver wake_tx_queue op during reconfig kprobes: Fix error check when reusing optimized probes kprobes: Mark ftrace mcount handler functions nokprobe x86/kprobes: Verify stack frame on kretprobe arm64: futex: Restore oldval initialization to work around buggy compilers crypto: x86/poly1305 - fix overflow during partial reduction ALSA: core: Fix card races between register and disconnect staging: comedi: ni_usb6501: Fix possible double-free of ->usb_rx_buf staging: comedi: ni_usb6501: Fix use of uninitialized mutex staging: comedi: vmk80xx: Fix possible double-free of ->usb_rx_buf staging: comedi: vmk80xx: Fix use of uninitialized semaphore io: accel: kxcjk1013: restore the range after resume. iio: adc: at91: disable adc channel interrupt in timeout case iio: ad_sigma_delta: select channel when reading register iio/gyro/bmg160: Use millidegrees for temperature scale KVM: x86: Don't clear EFER during SMM transitions for 32-bit vCPU tpm/tpm_i2c_atmel: Return -E2BIG when the transfer is incomplete modpost: file2alias: check prototype of handler modpost: file2alias: go back to simple devtable lookup crypto: crypto4xx - properly set IV after de- and encrypt ipv4: ensure rcu_read_lock() in ipv4_link_failure() ipv4: recompile ip options in ipv4_link_failure tcp: tcp_grow_window() needs to respect tcp_space() net: fou: do not use guehdr after iptunnel_pull_offloads in gue_udp_recv net: bridge: multicast: use rcu to access port list from br_multicast_start_querier net: atm: Fix potential Spectre v1 vulnerabilities bonding: fix event handling for stacked bonds appletalk: Fix compile regression ovl: fix uid/gid when creating over whiteout tpm/tpm_crb: Avoid unaligned reads in crb_recv() include/linux/swap.h: use offsetof() instead of custom __swapoffset macro lib/div64.c: off by one in shift appletalk: Fix use-after-free in atalk_proc_exit ARM: 8839/1: kprobe: make patch_lock a raw_spinlock_t iommu/dmar: Fix buffer overflow during PCI bus notification crypto: sha512/arm - fix crash bug in Thumb2 build crypto: sha256/arm - fix crash bug in Thumb2 build cifs: fallback to older infolevels on findfirst queryinfo retry ACPI / SBS: Fix GPE storm on recent MacBookPro's ARM: samsung: Limit SAMSUNG_PM_CHECK config option to non-Exynos platforms serial: uartps: console_setup() can't be placed to init section f2fs: fix to do sanity check with current segment number 9p locks: add mount option for lock retry interval 9p: do not trust pdu content for stat item size rsi: improve kernel thread handling to fix kernel panic ext4: prohibit fstrim in norecovery mode fix incorrect error code mapping for OBJECTID_NOT_FOUND x86/hw_breakpoints: Make default case in hw_breakpoint_arch_parse() return an error iommu/vt-d: Check capability before disabling protected memory x86/cpu/cyrix: Use correct macros for Cyrix calls on Geode processors x86/hpet: Prevent potential NULL pointer dereference perf tests: Fix a memory leak in test__perf_evsel__tp_sched_test() perf tests: Fix a memory leak of cpu_map object in the openat_syscall_event_on_all_cpus test perf evsel: Free evsel->counts in perf_evsel__exit() perf top: Fix error handling in cmd_top() tools/power turbostat: return the exit status of a command thermal/int340x_thermal: fix mode setting thermal/int340x_thermal: Add additional UUIDs ALSA: opl3: fix mismatch between snd_opl3_drum_switch definition and declaration mmc: davinci: remove extraneous __init annotation IB/mlx4: Fix race condition between catas error reset and aliasguid flows ALSA: sb8: add a check for request_region ALSA: echoaudio: add a check for ioremap_nocache ext4: report real fs size after failed resize ext4: add missing brelse() in add_new_gdb_meta_bg() perf/core: Restore mmap record type correctly PCI: Add function 1 DMA alias quirk for Marvell 9170 SATA controller xtensa: fix return_address sched/fair: Do not re-read ->h_load_next during hierarchical load calculation xen: Prevent buffer overflow in privcmd ioctl arm64: futex: Fix FUTEX_WAKE_OP atomic ops with non-zero result value ARM: dts: at91: Fix typo in ISC_D0 on PC9 genirq: Respect IRQCHIP_SKIP_SET_WAKE in irq_chip_set_wake_parent() block: do not leak memory in bio_copy_user_iov() ASoC: fsl_esai: fix channel swap issue when stream starts include/linux/bitrev.h: fix constant bitrev ALSA: seq: Fix OOB-reads from strlcpy ip6_tunnel: Match to ARPHRD_TUNNEL6 for dev type net: ethtool: not call vzalloc for zero sized memory request netns: provide pure entropy for net_hash_mix() tcp: Ensure DCTCP reacts to losses sctp: initialize _pad of sockaddr_in before copying to user memory qmi_wwan: add Olicard 600 openvswitch: fix flow actions reallocation net: rds: force to destroy connection if t_sock is NULL in rds_tcp_kill_sock(). ipv6: sit: reset ip header pointer in ipip6_rcv ipv6: Fix dangling pointer when ipv6 fragment tty: ldisc: add sysctl to prevent autoloading of ldiscs tty: mark Siemens R3964 line discipline as BROKEN lib/string.c: implement a basic bcmp x86/vdso: Drop implicit common-page-size linker flag x86: vdso: Use $LD instead of $CC to link x86/build: Specify elf_i386 linker emulation explicitly for i386 objects kbuild: clang: choose GCC_TOOLCHAIN_DIR not on LD binfmt_elf: switch to new creds when switching to new mm drm/dp/mst: Configure no_stop_bit correctly for remote i2c xfers dmaengine: tegra: avoid overflow of byte tracking x86/build: Mark per-CPU symbols as absolute explicitly for LLD wlcore: Fix memory leak in case wl12xx_fetch_firmware failure regulator: act8865: Fix act8600_sudcdc_voltage_ranges setting media: s5p-jpeg: Check for fmt_ver_flag when doing fmt enumeration netfilter: physdev: relax br_netfilter dependency dmaengine: imx-dma: fix warning comparison of distinct pointer types hpet: Fix missing '=' character in the __setup() code of hpet_mmap_enable soc/tegra: fuse: Fix illegal free of IO base address hwrng: virtio - Avoid repeated init of completion media: mt9m111: set initial frame size other than 0x0 tty: increase the default flip buffer limit to 2*640K ARM: avoid Cortex-A9 livelock on tight dmb loops mt7601u: bump supported EEPROM version soc: qcom: gsbi: Fix error handling in gsbi_probe() ASoC: fsl-asoc-card: fix object reference leaks in fsl_asoc_card_probe cdrom: Fix race condition in cdrom_sysctl_register fbdev: fbmem: fix memory access if logo is bigger than the screen bcache: improve sysfs_strtoul_clamp() bcache: fix input overflow to sequential_cutoff bcache: fix input overflow to cache set sysfs file io_error_halflife ALSA: PCM: check if ops are defined before suspending PCM ARM: 8833/1: Ensure that NEON code always compiles with Clang kprobes: Prohibit probing on bsearch() leds: lp55xx: fix null deref on firmware load failure media: mx2_emmaprp: Correct return type for mem2mem buffer helpers media: s5p-g2d: Correct return type for mem2mem buffer helpers media: s5p-jpeg: Correct return type for mem2mem buffer helpers media: sh_veu: Correct return type for mem2mem buffer helpers SoC: imx-sgtl5000: add missing put_device() perf test: Fix failure of 'evsel-tp-sched' test on s390 scsi: megaraid_sas: return error when create DMA pool failed IB/mlx4: Increase the timeout for CM cache e1000e: Fix -Wformat-truncation warnings mmc: omap: fix the maximum timeout setting ARM: 8840/1: use a raw_spinlock_t in unwind coresight: etm4x: Add support to enable ETMv4.2 scsi: core: replace GFP_ATOMIC with GFP_KERNEL in scsi_scan.c usb: chipidea: Grab the (legacy) USB PHY by phandle first tools lib traceevent: Fix buffer overflow in arg_eval fs: fix guard_bio_eod to check for real EOD errors cifs: Fix NULL pointer dereference of devname dm thin: add sanity checks to thin-pool and external snapshot creation cifs: use correct format characters fs/file.c: initialize init_files.resize_wait f2fs: do not use mutex lock in atomic context ocfs2: fix a panic problem caused by o2cb_ctl mm/slab.c: kmemleak no scan alien caches mm/vmalloc.c: fix kernel BUG at mm/vmalloc.c:512! mm/page_ext.c: fix an imbalance with kmemleak mm/cma.c: cma_declare_contiguous: correct err handling enic: fix build warning without CONFIG_CPUMASK_OFFSTACK sysctl: handle overflow for file-max gpio: gpio-omap: fix level interrupt idling tracing: kdb: Fix ftdump to not sleep h8300: use cc-cross-prefix instead of hardcoding h8300-unknown-linux- CIFS: fix POSIX lock leak and invalid ptr deref tty/serial: atmel: RS485 HD w/DMA: enable RX after TX is stopped Bluetooth: Fix decrementing reference count twice in releasing socket i2c: core-smbus: prevent stack corruption on read I2C_BLOCK_DATA mm: mempolicy: make mbind() return -EIO when MPOL_MF_STRICT is specified tty/serial: atmel: Add is_half_duplex helper lib/int_sqrt: optimize initial value compute ext4: cleanup bh release code in ext4_ind_remove_space() arm64: debug: Ensure debug handlers check triggering exception level arm64: debug: Don't propagate UNKNOWN FAR into si_code for debug signals Make arm64 serial port config compatible with crosvm Fix merge issue with 4.4.178 Fix merge issue with 4.4.177 ANDROID: cuttlefish_defconfig: Enable CONFIG_OVERLAY_FS Change-Id: I0d6e7b00f0198867803d5fe305ce13e205cc7518 Signed-off-by: Srinivasarao P <spathi@codeaurora.org>
| * mm/page_ext.c: fix an imbalance with kmemleakQian Cai2019-04-27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 0c81585499601acd1d0e1cbf424cabfaee60628c ] After offlining a memory block, kmemleak scan will trigger a crash, as it encounters a page ext address that has already been freed during memory offlining. At the beginning in alloc_page_ext(), it calls kmemleak_alloc(), but it does not call kmemleak_free() in free_page_ext(). BUG: unable to handle kernel paging request at ffff888453d00000 PGD 128a01067 P4D 128a01067 PUD 128a04067 PMD 47e09e067 PTE 800ffffbac2ff060 Oops: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN PTI CPU: 1 PID: 1594 Comm: bash Not tainted 5.0.0-rc8+ #15 Hardware name: HP ProLiant DL180 Gen9/ProLiant DL180 Gen9, BIOS U20 10/25/2017 RIP: 0010:scan_block+0xb5/0x290 Code: 85 6e 01 00 00 48 b8 00 00 30 f5 81 88 ff ff 48 39 c3 0f 84 5b 01 00 00 48 89 d8 48 c1 e8 03 42 80 3c 20 00 0f 85 87 01 00 00 <4c> 8b 3b e8 f3 0c fa ff 4c 39 3d 0c 6b 4c 01 0f 87 08 01 00 00 4c RSP: 0018:ffff8881ec57f8e0 EFLAGS: 00010082 RAX: 0000000000000000 RBX: ffff888453d00000 RCX: ffffffffa61e5a54 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff888453d00000 RBP: ffff8881ec57f920 R08: fffffbfff4ed588d R09: fffffbfff4ed588c R10: fffffbfff4ed588c R11: ffffffffa76ac463 R12: dffffc0000000000 R13: ffff888453d00ff9 R14: ffff8881f80cef48 R15: ffff8881f80cef48 FS: 00007f6c0e3f8740(0000) GS:ffff8881f7680000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffff888453d00000 CR3: 00000001c4244003 CR4: 00000000001606a0 Call Trace: scan_gray_list+0x269/0x430 kmemleak_scan+0x5a8/0x10f0 kmemleak_write+0x541/0x6ca full_proxy_write+0xf8/0x190 __vfs_write+0xeb/0x980 vfs_write+0x15a/0x4f0 ksys_write+0xd2/0x1b0 __x64_sys_write+0x73/0xb0 do_syscall_64+0xeb/0xaaa entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f6c0dad73b8 Code: 89 02 48 c7 c0 ff ff ff ff eb b3 0f 1f 80 00 00 00 00 f3 0f 1e fa 48 8d 05 65 63 2d 00 8b 00 85 c0 75 17 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 58 c3 0f 1f 80 00 00 00 00 41 54 49 89 d4 55 RSP: 002b:00007ffd5b863cb8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007f6c0dad73b8 RDX: 0000000000000005 RSI: 000055a9216e1710 RDI: 0000000000000001 RBP: 000055a9216e1710 R08: 000000000000000a R09: 00007ffd5b863840 R10: 000000000000000a R11: 0000000000000246 R12: 00007f6c0dda9780 R13: 0000000000000005 R14: 00007f6c0dda4740 R15: 0000000000000005 Modules linked in: nls_iso8859_1 nls_cp437 vfat fat kvm_intel kvm irqbypass efivars ip_tables x_tables xfs sd_mod ahci libahci igb i2c_algo_bit libata i2c_core dm_mirror dm_region_hash dm_log dm_mod efivarfs CR2: ffff888453d00000 ---[ end trace ccf646c7456717c5 ]--- Kernel panic - not syncing: Fatal exception Shutting down cpus with NMI Kernel Offset: 0x24c00000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff) ---[ end Kernel panic - not syncing: Fatal exception ]--- Link: http://lkml.kernel.org/r/20190227173147.75650-1-cai@lca.pw Signed-off-by: Qian Cai <cai@lca.pw> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
* | platform: msm: resolve NULL pointer dereference issueYao Jiang2018-08-16
| | | | | | | | | | | | | | Fix some null pointer dereference flaw and parameter not init issues. change-Id: I0ed5f3f62c3794775bf97d353c4e50dd8ceb32da Signed-off-by: Yao Jiang <yaojia@codeaurora.org>
* | Merge android-4.4.101 (f0b9d2d) into msm-4.4Srinivasarao P2017-12-26
|\| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * refs/heads/tmp-f0b9d2d Linux 4.4.101 mm/pagewalk.c: report holes in hugetlb ranges mm/page_ext.c: check if page_ext is not prepared mm: check the return value of lookup_page_ext for all call sites coda: fix 'kernel memory exposure attempt' in fsync mm/page_alloc.c: broken deferred calculation ipmi: fix unsigned long underflow ocfs2: should wait dio before inode lock in ocfs2_setattr() nvme: Fix memory order on async queue deletion arm64: fix dump_instr when PAN and UAO are in use serial: omap: Fix EFR write on RTS deassertion ima: do not update security.ima if appraisal status is not INTEGRITY_PASS net/sctp: Always set scope_id in sctp_inet6_skb_msgname fealnx: Fix building error on MIPS sctp: do not peel off an assoc from one netns to another one af_netlink: ensure that NLMSG_DONE never fails in dumps vlan: fix a use-after-free in vlan_device_event() bonding: discard lowest hash bit for 802.3ad layer3+4 netfilter/ipvs: clear ipvs_property flag when SKB net namespace changed tcp: do not mangle skb->cb[] in tcp_make_synack() Conflicts: mm/debug-pagealloc.c mm/page_ext.c mm/page_owner.c Change-Id: I551aff1b4c8a0d72f64a234abb8ac88990fbc9e5 Signed-off-by: Srinivasarao P <spathi@codeaurora.org>
| * mm/page_ext.c: check if page_ext is not preparedJaewon Kim2017-11-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit e492080e640c2d1235ddf3441cae634cfffef7e1 upstream. online_page_ext() and page_ext_init() allocate page_ext for each section, but they do not allocate if the first PFN is !pfn_present(pfn) or !pfn_valid(pfn). Then section->page_ext remains as NULL. lookup_page_ext checks NULL only if CONFIG_DEBUG_VM is enabled. For a valid PFN, __set_page_owner will try to get page_ext through lookup_page_ext. Without CONFIG_DEBUG_VM lookup_page_ext will misuse NULL pointer as value 0. This incurrs invalid address access. This is the panic example when PFN 0x100000 is not valid but PFN 0x13FC00 is being used for page_ext. section->page_ext is NULL, get_entry returned invalid page_ext address as 0x1DFA000 for a PFN 0x13FC00. To avoid this panic, CONFIG_DEBUG_VM should be removed so that page_ext will be checked at all times. Unable to handle kernel paging request at virtual address 01dfa014 ------------[ cut here ]------------ Kernel BUG at ffffff80082371e0 [verbose debug info unavailable] Internal error: Oops: 96000045 [#1] PREEMPT SMP Modules linked in: PC is at __set_page_owner+0x48/0x78 LR is at __set_page_owner+0x44/0x78 __set_page_owner+0x48/0x78 get_page_from_freelist+0x880/0x8e8 __alloc_pages_nodemask+0x14c/0xc48 __do_page_cache_readahead+0xdc/0x264 filemap_fault+0x2ac/0x550 ext4_filemap_fault+0x3c/0x58 __do_fault+0x80/0x120 handle_mm_fault+0x704/0xbb0 do_page_fault+0x2e8/0x394 do_mem_abort+0x88/0x124 Pre-4.7 kernels also need commit f86e4271978b ("mm: check the return value of lookup_page_ext for all call sites"). Link: http://lkml.kernel.org/r/20171107094131.14621-1-jaewon31.kim@samsung.com Fixes: eefa864b701d ("mm/page_ext: resurrect struct page extending code for debugging") Signed-off-by: Jaewon Kim <jaewon31.kim@samsung.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Minchan Kim <minchan@kernel.org> Cc: Joonsoo Kim <js1304@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | mm: enable page poisoning early at bootVinayak Menon2017-04-14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On SPARSEMEM systems page poisoning is enabled after buddy is up, because of the dependency on page extension init. This causes the pages released by free_all_bootmem not to be poisoned. This either delays or misses the identification of some issues because the pages have to undergo another cycle of alloc-free-alloc for any corruption to be detected. Enable page poisoning early by getting rid of the PAGE_EXT_DEBUG_POISON flag. Since all the free pages will now be poisoned, the flag need not be verified before checking the poison during an alloc. Link: http://lkml.kernel.org/r/1490358246-11001-1-git-send-email-vinmenon@codeaurora.org Acked-by: Laura Abbott <labbott@redhat.com> Tested-by: Laura Abbott <labbott@redhat.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Akinobu Mita <akinobu.mita@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> [vinmenon@codeaurora.org: resolve trivial merge conflicts. Remove the redundant free pages RO feature from the page_poison.c file which is the reason for conflicts + squash the addendum commit 40961ef8d65f51093bc94de110b97b590b6b9275 ('mm-enable-page-poisoning-early-at-boot-v2')] Git-commit: c5b7cd344fd6341e6db79e55c0f1f4d1d9c67a7e Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git Change-Id: I1bb1f99d3a2e1135131911905e0916c837ba9d8a Signed-off-by: Vinayak Menon <vinmenon@codeaurora.org>
* | mm/page_poisoning.c: allow for zero poisoningLaura Abbott2017-04-14
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | By default, page poisoning uses a poison value (0xaa) on free. If this is changed to 0, the page is not only sanitized but zeroing on alloc with __GFP_ZERO can be skipped as well. The tradeoff is that detecting corruption from the poisoning is harder to detect. This feature also cannot be used with hibernation since pages are not guaranteed to be zeroed after hibernation. Credit to Grsecurity/PaX team for inspiring this work Change-Id: If7116e6bff246abbafc38bdfeb3601d3ea063ad2 Signed-off-by: Laura Abbott <labbott@fedoraproject.org> Acked-by: Rafael J. Wysocki <rjw@rjwysocki.net> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Michal Hocko <mhocko@suse.com> Cc: Kees Cook <keescook@chromium.org> Cc: Mathias Krause <minipli@googlemail.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Jianyu Zhan <nasa4836@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Git-commit: 1414c7f4f7d72d138fff35f00151d15749b5beda Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git Signed-off-by: Vinayak Menon <vinmenon@codeaurora.org>
* mm: introduce idle page trackingVladimir Davydov2015-09-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Knowing the portion of memory that is not used by a certain application or memory cgroup (idle memory) can be useful for partitioning the system efficiently, e.g. by setting memory cgroup limits appropriately. Currently, the only means to estimate the amount of idle memory provided by the kernel is /proc/PID/{clear_refs,smaps}: the user can clear the access bit for all pages mapped to a particular process by writing 1 to clear_refs, wait for some time, and then count smaps:Referenced. However, this method has two serious shortcomings: - it does not count unmapped file pages - it affects the reclaimer logic To overcome these drawbacks, this patch introduces two new page flags, Idle and Young, and a new sysfs file, /sys/kernel/mm/page_idle/bitmap. A page's Idle flag can only be set from userspace by setting bit in /sys/kernel/mm/page_idle/bitmap at the offset corresponding to the page, and it is cleared whenever the page is accessed either through page tables (it is cleared in page_referenced() in this case) or using the read(2) system call (mark_page_accessed()). Thus by setting the Idle flag for pages of a particular workload, which can be found e.g. by reading /proc/PID/pagemap, waiting for some time to let the workload access its working set, and then reading the bitmap file, one can estimate the amount of pages that are not used by the workload. The Young page flag is used to avoid interference with the memory reclaimer. A page's Young flag is set whenever the Access bit of a page table entry pointing to the page is cleared by writing to the bitmap file. If page_referenced() is called on a Young page, it will add 1 to its return value, therefore concealing the fact that the Access bit was cleared. Note, since there is no room for extra page flags on 32 bit, this feature uses extended page flags when compiled on 32 bit. [akpm@linux-foundation.org: fix build] [akpm@linux-foundation.org: kpageidle requires an MMU] [akpm@linux-foundation.org: decouple from page-flags rework] Signed-off-by: Vladimir Davydov <vdavydov@parallels.com> Reviewed-by: Andres Lagar-Cavilla <andreslc@google.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Greg Thelen <gthelen@google.com> Cc: Michel Lespinasse <walken@google.com> Cc: David Rientjes <rientjes@google.com> Cc: Pavel Emelyanov <xemul@parallels.com> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/page_owner: keep track of page ownersJoonsoo Kim2014-12-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is the page owner tracking code which is introduced so far ago. It is resident on Andrew's tree, though, nobody tried to upstream so it remain as is. Our company uses this feature actively to debug memory leak or to find a memory hogger so I decide to upstream this feature. This functionality help us to know who allocates the page. When allocating a page, we store some information about allocation in extra memory. Later, if we need to know status of all pages, we can get and analyze it from this stored information. In previous version of this feature, extra memory is statically defined in struct page, but, in this version, extra memory is allocated outside of struct page. It enables us to turn on/off this feature at boottime without considerable memory waste. Although we already have tracepoint for tracing page allocation/free, using it to analyze page owner is rather complex. We need to enlarge the trace buffer for preventing overlapping until userspace program launched. And, launched program continually dump out the trace buffer for later analysis and it would change system behaviour with more possibility rather than just keeping it in memory, so bad for debug. Moreover, we can use page_owner feature further for various purposes. For example, we can use it for fragmentation statistics implemented in this patch. And, I also plan to implement some CMA failure debugging feature using this interface. I'd like to give the credit for all developers contributed this feature, but, it's not easy because I don't know exact history. Sorry about that. Below is people who has "Signed-off-by" in the patches in Andrew's tree. Contributor: Alexander Nyberg <alexn@dsv.su.se> Mel Gorman <mgorman@suse.de> Dave Hansen <dave@linux.vnet.ibm.com> Minchan Kim <minchan@kernel.org> Michal Nazarewicz <mina86@mina86.com> Andrew Morton <akpm@linux-foundation.org> Jungsoo Son <jungsoo.son@lge.com> Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Dave Hansen <dave@sr71.net> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Jungsoo Son <jungsoo.son@lge.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/debug-pagealloc: prepare boottime configurable on/offJoonsoo Kim2014-12-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Until now, debug-pagealloc needs extra flags in struct page, so we need to recompile whole source code when we decide to use it. This is really painful, because it takes some time to recompile and sometimes rebuild is not possible due to third party module depending on struct page. So, we can't use this good feature in many cases. Now, we have the page extension feature that allows us to insert extra flags to outside of struct page. This gets rid of third party module issue mentioned above. And, this allows us to determine if we need extra memory for this page extension in boottime. With these property, we can avoid using debug-pagealloc in boottime with low computational overhead in the kernel built with CONFIG_DEBUG_PAGEALLOC. This will help our development process greatly. This patch is the preparation step to achive above goal. debug-pagealloc originally uses extra field of struct page, but, after this patch, it will use field of struct page_ext. Because memory for page_ext is allocated later than initialization of page allocator in CONFIG_SPARSEMEM, we should disable debug-pagealloc feature temporarily until initialization of page_ext. This patch implements this. Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Dave Hansen <dave@sr71.net> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Jungsoo Son <jungsoo.son@lge.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/page_ext: resurrect struct page extending code for debuggingJoonsoo Kim2014-12-13
When we debug something, we'd like to insert some information to every page. For this purpose, we sometimes modify struct page itself. But, this has drawbacks. First, it requires re-compile. This makes us hesitate to use the powerful debug feature so development process is slowed down. And, second, sometimes it is impossible to rebuild the kernel due to third party module dependency. At third, system behaviour would be largely different after re-compile, because it changes size of struct page greatly and this structure is accessed by every part of kernel. Keeping this as it is would be better to reproduce errornous situation. This feature is intended to overcome above mentioned problems. This feature allocates memory for extended data per page in certain place rather than the struct page itself. This memory can be accessed by the accessor functions provided by this code. During the boot process, it checks whether allocation of huge chunk of memory is needed or not. If not, it avoids allocating memory at all. With this advantage, we can include this feature into the kernel in default and can avoid rebuild and solve related problems. Until now, memcg uses this technique. But, now, memcg decides to embed their variable to struct page itself and it's code to extend struct page has been removed. I'd like to use this code to develop debug feature, so this patch resurrect it. To help these things to work well, this patch introduces two callbacks for clients. One is the need callback which is mandatory if user wants to avoid useless memory allocation at boot-time. The other is optional, init callback, which is used to do proper initialization after memory is allocated. Detailed explanation about purpose of these functions is in code comment. Please refer it. Others are completely same with previous extension code in memcg. Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Dave Hansen <dave@sr71.net> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Jungsoo Son <jungsoo.son@lge.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>