mtd: nand: s3c2410: fix bug in s3c2410_nand_correct_data()
If there is only one bit difference in the ECC, the function should
return 1.
The result of "diff0 & ~(1<<fls(diff0))" is equal to diff0, so the
function actually returns -1.
Signed-off-by: Zhaoxiu Zeng <zhaoxiu.zeng@gmail.com> Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Raghav Dogra [Wed, 17 Feb 2016 11:24:18 +0000 (16:54 +0530)]
mtd/ifc: Add support for IFC controller version 2.0
The new IFC controller version 2.0 has a different memory map page.
Upto IFC 1.4 PAGE size is 4 KB and from IFC2.0 PAGE size is 64KB.
This patch segregates the IFC global and runtime registers to appropriate
PAGE sizes.
Signed-off-by: Jaiprakash Singh <b44839@freescale.com> Signed-off-by: Raghav Dogra <raghav@freescale.com> Acked-by: Li Yang <leoyang.li@nxp.com> Signed-off-by: Raghav Dogra <raghav.dogra@nxp.com> Acked-by: Scott Wood <oss@buserror.net> Acked-by: Brian Norris <computersforpeace@gmail.com> Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Ezequiel García [Fri, 1 Apr 2016 21:29:24 +0000 (18:29 -0300)]
mtd: nand: Remove BUG() abuse in nand_scan_tail
There's no reason to BUG() when parameters are being
validated. Drivers can get things wrong, and it's much nicer
to just throw a noisy warn and fail gracefully, than calling
BUG() and throwing the whole system down the drain.
Signed-off-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar> Reviewed-by: Richard Weinberger <richard@nod.at> Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
fix the raw_buffer pointer double free issue found by coverify.
CID 18344 (#2 of 2): Double free (USE_AFTER_FREE)
3. double_free: Calling gpmi_alloc_dma_buffer frees pointer
this->raw_buffer which has already been freed
Signed-off-by: Han Xu <han.xu@nxp.com> Reviewed-by: Richard Weinberger <richard@nod.at> Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Florian Fainelli [Thu, 10 Mar 2016 23:34:16 +0000 (15:34 -0800)]
mtd: brcmnand: Add support for v6.2 controllers
Document and match the brcm,brcmnand-v6.2 compatible string, the controller has
a register layout identical to the v6.0 version and supports prefetch. Update the
command shift logic to account for v6.2 controller which are the first ones to
use a shift of 0 (6.1 used a shift of 24).
Signed-off-by: Kamal Dasu <kdasu.kdev@gmail.com> Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Acked-by: Rob Herring <robh@kernel.org> Acked-by: Brian Norris <computersforpeace@gmail.com> Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Boris Brezillon [Fri, 1 Apr 2016 12:26:35 +0000 (14:26 +0200)]
mtd: nand: document the NAND controller/NAND chip DT representation
Standardize the NAND controller/NAND chip DT representation. Now, all new
NAND controller drivers should comply with this representation, even if
they are only supporting a single NAND chip.
Existing drivers can keep support for the old representation (where only
the NAND chip was described), but are encouraged to also support the new
one.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Acked-by: Brian Norris <computersforpeace@gmail.com> Acked-by: Rob Herring <robh@kernel.org>
Boris Brezillon [Tue, 1 Mar 2016 13:11:52 +0000 (14:11 +0100)]
mtd: nand: atmel: correct bitflips in erased pages for pre-sama5d4 SoCs
New atmel SoCs are able to fix bitflips in erased pages, but old ones
are still impacted by this problem. Use nand_check_erased_ecc_chunk() to
handle this case.
Rafał Miłecki [Wed, 23 Mar 2016 10:19:01 +0000 (11:19 +0100)]
of: mtd: prepare helper reading NAND ECC algo from DT
NAND subsystem is being slightly reworked to store ECC details in
separated fields. In future we'll want to add support for more DT
properties as specifying every possible setup with a single
"nand-ecc-mode" is a pretty bad idea.
To allow this let's add a helper that will support something like
"nand-ecc-algo" in future. Right now we use it for keeping backward
compatibility.
Signed-off-by: Rafał Miłecki <zajec5@gmail.com> Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Rafał Miłecki [Wed, 23 Mar 2016 10:19:00 +0000 (11:19 +0100)]
mtd: nand: add new enum for storing ECC algorithm
Our nand_ecc_modes_t is already a bit abused by value NAND_ECC_SOFT_BCH.
This enum should store ECC mode only and putting algorithm details there
is a bad idea. It would result in too many values impossible to support
in a sane way.
To solve this problem let's add a new enum. We'll have to modify all
drivers to set it properly but once it's done it'll be possible to drop
NAND_ECC_SOFT_BCH. That will result in a cleaner design and more
possibilities like setting ECC algorithm for hardware ECC mode.
Signed-off-by: Rafał Miłecki <zajec5@gmail.com> Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Boris Brezillon [Tue, 19 Apr 2016 19:44:11 +0000 (21:44 +0200)]
Merge branch 'mtd-nand-trigger' of git://git.kernel.org/pub/scm/linux/kernel/git/j.anaszewski/linux-leds into nand/next
Pull leds-trigger changes from Jacek Anaszewski.
Create a generic mtd led-trigger to replace the exisitng nand led-trigger
implementation.
* 'mtd-nand-trigger' of git://git.kernel.org/pub/scm/linux/kernel/git/j.anaszewski/linux-leds:
mtd: Hook I/O activity to the MTD LED trigger
mtd: nand: Remove the "nand-disk" LED trigger
leds: trigger: Introduce a MTD (NAND/NOR) trigger
mtd: Uninline mtd_write_oob and move it to mtdcore.c
leds: trigger: Introduce a kernel panic LED trigger
Boris Brezillon [Tue, 19 Apr 2016 19:39:22 +0000 (21:39 +0200)]
Merge branch 'for-v4.7/gpmc-mtd-common' of github.com:rogerq/linux into nand/next
Pull NAND/GPMC updates from Roger Quadros:
"We do a couple of things in this series which result in cleaner device
tree implementation, faster perfomance and multi-platform support. As
an added bonus we get to use the GPMC_WAIT pins as GPI/Interrupts.
- Establish a custom interface between NAND and GPMC driver. This is
needed because all of the NAND registers sit in the GPMC register
space.
- Clean up device tree support so that omap-gpmc IP and the omap2 NAND
driver can be used on non-OMAP platforms. e.g. Keystone.
- Implement GPIOCHIP for the GPMC WAITPINS. SoCs can contain 2 to 4 of
these and most of them would be unused otherwise. It also allows a
cleaner implementation of NAND Ready pin status for the NAND driver.
- Implement GPMC IRQ domain to proivde the 2 NAND events and GPMC
WAITPIN edge interrupts.
- Implement GPIOlib based NAND ready pin checking for OMAP NAND driver.
On dra7-evm, Read speed increases from 13768 KiB/ to 17246 KiB/s.
Write speed was unchanged at 7123 KiB/s."
* 'for-v4.7/gpmc-mtd-common' of github.com:rogerq/linux:
mtd: nand: omap2: Implement NAND ready using gpiolib
memory: omap-gpmc: Prevent GPMC_STATUS from being accessed via gpmc_regs
memory: omap-gpmc: Support WAIT pin edge interrupts
memory: omap-gpmc: Reserve WAITPIN if needed for WAIT monitoring
memory: omap-gpmc: Support general purpose input for WAITPINs
memory: omap-gpmc: Move device tree binding to correct location
memory: omap-gpmc: Prevent mapping into 1st 16MB
mtd: nand: omap: Update DT binding documentation
mtd: nand: omap: Clean up device tree support
mtd: nand: omap: Copy platform data parameters to omap_nand_info data
mtd: nand: omap: Switch to using GPMC-NAND ops for writebuffer empty check
mtd: nand: omap: Use gpmc_omap_get_nand_ops() to get NAND registers
memory: omap-gpmc: Implement IRQ domain for NAND IRQs
memory: omap-gpmc: Add GPMC-NAND ops to get writebufferempty status
memory: omap-gpmc: Introduce GPMC to NAND interface
ARM: OMAP2+: gpmc: Add gpmc timings and settings to platform data
ARM: OMAP2+: gpmc: Add platform data
Roger Quadros [Thu, 6 Aug 2015 14:39:35 +0000 (17:39 +0300)]
mtd: nand: omap2: Implement NAND ready using gpiolib
The GPMC WAIT pin status are now available over gpiolib.
Update the omap_dev_ready() function to use gpio instead of
directly accessing GPMC register space.
Signed-off-by: Roger Quadros <rogerq@ti.com> Acked-by: Brian Norris <computersforpeace@gmail.com> Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com> Acked-by: Tony Lindgren <tony@atomide.com>
Roger Quadros [Mon, 26 May 2014 08:54:45 +0000 (11:54 +0300)]
mtd: nand: omap: Update DT binding documentation
Add compatible id and interrupts. The NAND interrupts are
provided by the GPMC controller node.
Signed-off-by: Roger Quadros <rogerq@ti.com> Acked-by: Rob Herring <robh@kernel.org> Acked-by: Brian Norris <computersforpeace@gmail.com> Acked-by: Tony Lindgren <tony@atomide.com>
Roger Quadros [Tue, 20 May 2014 19:29:28 +0000 (22:29 +0300)]
mtd: nand: omap: Copy platform data parameters to omap_nand_info data
Copy all the platform data parameters to the driver's local data
structure 'omap_nand_info' and use it in the entire driver. This will
make it easer for device tree migration.
Signed-off-by: Roger Quadros <rogerq@ti.com> Acked-by: Brian Norris <computersforpeace@gmail.com> Acked-by: Tony Lindgren <tony@atomide.com>
Roger Quadros [Wed, 5 Aug 2015 10:36:43 +0000 (13:36 +0300)]
mtd: nand: omap: Switch to using GPMC-NAND ops for writebuffer empty check
Instead of accessing the gpmc_status register directly start
using the gpmc_nand_ops->nand_writebuffer_empty() helper
to check write buffer empty status.
Signed-off-by: Roger Quadros <rogerq@ti.com> Acked-by: Brian Norris <computersforpeace@gmail.com> Acked-by: Tony Lindgren <tony@atomide.com>
Roger Quadros [Thu, 30 Jul 2015 11:49:23 +0000 (14:49 +0300)]
memory: omap-gpmc: Implement IRQ domain for NAND IRQs
GPMC provides 2 interrupts for NAND use. i.e. fifoevent and termcount.
Use IRQ domain for this. NAND device tree node can then
get the necessary interrupts by using gpmc as the interrupt parent.
Legacy boot uses gpmc_get_client_irq to get the
NAND interrupts from the GPMC IRQ domain.
Get rid of custom bitmasks and use IRQ domain for that
as well.
Signed-off-by: Roger Quadros <rogerq@ti.com> Acked-by: Rob Herring <robh@kernel.org> Acked-by: Tony Lindgren <tony@atomide.com>
Roger Quadros [Wed, 5 Aug 2015 10:58:01 +0000 (13:58 +0300)]
memory: omap-gpmc: Introduce GPMC to NAND interface
The OMAP GPMC module has certain registers dedicated for NAND
access and some NAND bits mixed with other GPMC functionality.
For the NAND dedicated registers we have the struct gpmc_nand_regs.
The NAND driver needs to access NAND specific bits from the
following non-dedicated registers
- EMPTYWRITEBUFFERSTATUS from GPMC_STATUS
For accessing these bits we introduce the struct gpmc_nand_ops.
Add gpmc_omap_get_nand_ops() that returns the gpmc_nand_ops along
with updating the gpmc_nand_regs. This API will be called by the
OMAP NAND driver to access the necessary bits in GPMC register space.
Signed-off-by: Roger Quadros <rogerq@ti.com> Acked-by: Tony Lindgren <tony@atomide.com>
Roger Quadros [Fri, 10 Jul 2015 12:23:28 +0000 (15:23 +0300)]
ARM: OMAP2+: gpmc: Add platform data
Add a platform data structure for GPMC. It contains all the necessary
platform information that needs to be passed from platform init code
to GPMC driver.
Signed-off-by: Roger Quadros <rogerq@ti.com> Acked-by: Tony Lindgren <tony@atomide.com>
This commit removes the "nand-disk" LED trigger from the
NAND code.
A trigger with the same name is already available selecting
LEDS_TRIGGER_MTD. Note that "nand-disk" trigger is being
deprecated in favor of the "mtd" trigger.
Signed-off-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar> Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
This commit introduces a MTD trigger for flash (NAND/NOR) device
activity. The implementation is copied from IDE disk.
This trigger deprecates the "nand-disk" LED trigger, but for backwards
compatibility, we still keep the "nand-disk" trigger around.
The motivation for deprecating the "nand-disk" LED trigger is that
it only works for NAND drivers, whereas the "mtd" LED trigger
is more generic (in fact, "nand-disk" currently only works for
certain NAND drivers).
Signed-off-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar> Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Ezequiel Garcia [Tue, 29 Mar 2016 20:35:47 +0000 (17:35 -0300)]
leds: trigger: Introduce a kernel panic LED trigger
This commit introduces a new LED trigger which allows to configure
a LED to blink on a kernel panic (through panic_blink).
Notice that currently the Openmoko FreeRunner (GTA02) mach code
sets panic_blink to blink a hard-coded LED. The new trigger is
meant to introduce a generic mechanism to achieve this.
Signed-off-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar> Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Linus Torvalds [Sat, 26 Mar 2016 22:53:16 +0000 (15:53 -0700)]
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client
Pull Ceph updates from Sage Weil:
"There is quite a bit here, including some overdue refactoring and
cleanup on the mon_client and osd_client code from Ilya, scattered
writeback support for CephFS and a pile of bug fixes from Zheng, and a
few random cleanups and fixes from others"
[ I already decided not to pull this because of it having been rebased
recently, but ended up changing my mind after all. Next time I'll
really hold people to it. Oh well. - Linus ]
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: (34 commits)
libceph: use KMEM_CACHE macro
ceph: use kmem_cache_zalloc
rbd: use KMEM_CACHE macro
ceph: use lookup request to revalidate dentry
ceph: kill ceph_get_dentry_parent_inode()
ceph: fix security xattr deadlock
ceph: don't request vxattrs from MDS
ceph: fix mounting same fs multiple times
ceph: remove unnecessary NULL check
ceph: avoid updating directory inode's i_size accidentally
ceph: fix race during filling readdir cache
libceph: use sizeof_footer() more
ceph: kill ceph_empty_snapc
ceph: fix a wrong comparison
ceph: replace CURRENT_TIME by current_fs_time()
ceph: scattered page writeback
libceph: add helper that duplicates last extent operation
libceph: enable large, variable-sized OSD requests
libceph: osdc->req_mempool should be backed by a slab pool
libceph: make r_request msg_size calculation clearer
...
Linus Torvalds [Sat, 26 Mar 2016 19:59:04 +0000 (12:59 -0700)]
Merge tag 'ofs-pull-tag-1' of git://git.kernel.org/pub/scm/linux/kernel/git/hubcap/linux
Pull orangefs filesystem from Mike Marshall.
This finally merges the long-pending orangefs filesystem, which has been
much cleaned up with input from Al Viro over the last six months. From
the documentation file:
"OrangeFS is an LGPL userspace scale-out parallel storage system. It
is ideal for large storage problems faced by HPC, BigData, Streaming
Video, Genomics, Bioinformatics.
Orangefs, originally called PVFS, was first developed in 1993 by Walt
Ligon and Eric Blumer as a parallel file system for Parallel Virtual
Machine (PVM) as part of a NASA grant to study the I/O patterns of
parallel programs.
Orangefs features include:
- Distributes file data among multiple file servers
- Supports simultaneous access by multiple clients
- Stores file data and metadata on servers using local file system
and access methods
- Userspace implementation is easy to install and maintain
- Direct MPI support
- Stateless"
see Documentation/filesystems/orangefs.txt for more in-depth details.
* tag 'ofs-pull-tag-1' of git://git.kernel.org/pub/scm/linux/kernel/git/hubcap/linux: (174 commits)
orangefs: fix orangefs_superblock locking
orangefs: fix do_readv_writev() handling of error halfway through
orangefs: have ->kill_sb() evict the VFS side of things first
orangefs: sanitize ->llseek()
orangefs-bufmap.h: trim unused junk
orangefs: saner calling conventions for getting a slot
orangefs_copy_{to,from}_bufmap(): don't pass bufmap pointer
orangefs: get rid of readdir_handle_s
ornagefs: ensure that truncate has an up to date inode size
orangefs: move code which sets i_link to orangefs_inode_getattr
orangefs: remove needless wrapper around GFP_KERNEL
orangefs: remove wrapper around mutex_lock(&inode->i_mutex)
orangefs: refactor inode type or link_target change detection
orangefs: use new getattr for revalidate and remove old getattr
orangefs: use new getattr in inode getattr and permission
orangefs: use new orangefs_inode_getattr to get size in write and llseek
orangefs: use new orangefs_inode_getattr to create new inodes
orangefs: rename orangefs_inode_getattr to orangefs_inode_old_getattr
orangefs: remove inode->i_lock wrapper
orangefs: put register_chrdev immediately before register_filesystem
...
Linus Torvalds [Sat, 26 Mar 2016 18:37:42 +0000 (11:37 -0700)]
Merge tag 'ntb-4.6' of git://github.com/jonmason/ntb
Pull NTB bug fixes from Jon Mason:
"NTB bug fixes for tasklet from spinning forever, link errors,
translation window setup, NULL ptr dereference, and ntb-perf errors.
Also, a modification to the driver API that makes _addr functions
optional"
* tag 'ntb-4.6' of git://github.com/jonmason/ntb:
NTB: Remove _addr functions from ntb_hw_amd
NTB: Make _addr functions optional in the API
NTB: Fix incorrect clean up routine in ntb_perf
NTB: Fix incorrect return check in ntb_perf
ntb: fix possible NULL dereference
ntb: add missing setup of translation window
ntb: stop link work when we do not have memory
ntb: stop tasklet from spinning forever during shutdown.
ntb: perf test: fix address space confusion
Linus Torvalds [Sat, 26 Mar 2016 18:31:01 +0000 (11:31 -0700)]
Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull more SCSI updates from James Bottomley:
"The only new stuff which missed the first pull request is an update to
the UFS driver.
The rest is an assortment of bug fixes and minor tweaks which appeared
recently (some are fixes for recent code and some are stuff spotted
recently by the checkers or the new gcc-6 compiler [most of Arnd's
stuff])"
* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (32 commits)
scsi_common: do not clobber fixed sense information
scsi: ufs: select CONFIG_NLS
scsi: fc: use get/put_unaligned64 for wwn access
fnic: move printk()s outside of the critical code section.
qla2xxx: avoid maybe_uninitialized warning
megaraid_sas: add missing curly braces in ioctl handler
lpfc: fix misleading indentation
scsi_transport_sas: add 'scsi_target_id' sysfs attribute
scsi_dh_alua: uninitialized variable in alua_check_vpd()
scsi: ufs-qcom: add printouts of testbus debug registers
scsi: ufs-qcom: enable/disable the device ref clock
scsi: ufs-qcom: set PA_Local_TX_LCC_Enable before link startup
scsi: ufs: add device quirk delay before putting UFS rails in LPM
scsi: ufs: fix leakage during link off state
scsi: ufs: tune UniPro parameters to optimize hibern8 exit time
scsi: ufs: handle non spec compliant bkops behaviour by device
scsi: ufs: add retry for query descriptors
scsi: ufs: add error recovery after DL NAC error
scsi: ufs: make error handling bit faster
scsi: ufs: disable vccq if it's not needed by UFS device
...
Linus Torvalds [Sat, 26 Mar 2016 17:13:05 +0000 (10:13 -0700)]
f2fs/crypto: fix xts_tweak initialization
Commit 0b81d07790726 ("fs crypto: move per-file encryption from f2fs
tree to fs/crypto") moved the f2fs crypto files to fs/crypto/ and
renamed the symbol prefixes from "f2fs_" to "fscrypt_" (and from "F2FS_"
to just "FS" for preprocessor symbols).
Because of the symbol renaming, it's a bit hard to see it as a file
move: use
to lower the rename detection to just 30% similarity and make git show
the files as renamed (the header file won't be shown as a rename even
then - since all it contains is symbol definitions, it looks almost
completely different).
Even with the renames showing as renames, the diffs are not all that
easy to read, since so much is just the renames. But Eric Biggers
noticed that it's not just all renames: the initialization of the
xts_tweak had been broken too, using the inode number rather than the
page offset.
That's not right - it makes the xfs_tweak the same for all pages of each
inode. It _might_ make sense to make the xfs_tweak contain both the
offset _and_ the inode number, but not just the inode number.
Reported-by: Eric Biggers <ebiggers3@gmail.com> Cc: Jaegeuk Kim <jaegeuk@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Allen Hubbe [Mon, 21 Mar 2016 08:53:14 +0000 (04:53 -0400)]
NTB: Remove _addr functions from ntb_hw_amd
Kernel zero day testing warned about address space confusion. A virtual
iomem address was used where a physical address is expected. The
offending functions implement an optional part of the api, so they are
removed. They can be added later, after testing.
Fixes: a1b3695820aa490e58915d720a1438069813008b Signed-off-by: Allen Hubbe <Allen.Hubbe@emc.com> Acked-by: Xiangliang Yu <Xiangliang.Yu@amd.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
Al Viro [Fri, 25 Mar 2016 23:56:34 +0000 (19:56 -0400)]
orangefs: fix orangefs_superblock locking
* switch orangefs_remount() to taking ORANGEFS_SB(sb) instead of sb
* remove from the list _before_ orangefs_unmount() - request_mutex
in the latter will make sure that nothing observed in the loop in
ORANGEFS_DEV_REMOUNT_ALL handling will get freed until the end
of loop
* on removal, keep the forward pointer and zero the back one. That
way we can drop and regain the spinlock in the loop body (again,
ORANGEFS_DEV_REMOUNT_ALL one) and still be able to get to the
rest of the list.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Mike Marshall <hubcap@omnibond.com>
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (42 commits)
thp: fix typo in khugepaged_scan_pmd()
MAINTAINERS: fill entries for KASAN
mm/filemap: generic_file_read_iter(): check for zero reads unconditionally
kasan: test fix: warn if the UAF could not be detected in kmalloc_uaf2
mm, kasan: stackdepot implementation. Enable stackdepot for SLAB
arch, ftrace: for KASAN put hard/soft IRQ entries into separate sections
mm, kasan: add GFP flags to KASAN API
mm, kasan: SLAB support
kasan: modify kmalloc_large_oob_right(), add kmalloc_pagealloc_oob_right()
include/linux/oom.h: remove undefined oom_kills_count()/note_oom_kill()
mm/page_alloc: prevent merging between isolated and other pageblocks
drivers/memstick/host/r592.c: avoid gcc-6 warning
ocfs2: extend enough credits for freeing one truncate record while replaying truncate records
ocfs2: extend transaction for ocfs2_remove_rightmost_path() and ocfs2_update_edge_lengths() before to avoid inconsistency between inode and et
ocfs2/dlm: move lock to the tail of grant queue while doing in-place convert
ocfs2: solve a problem of crossing the boundary in updating backups
ocfs2: fix occurring deadlock by changing ocfs2_wq from global to local
ocfs2/dlm: fix BUG in dlm_move_lockres_to_recovery_list
ocfs2/dlm: fix race between convert and recovery
ocfs2: fix a deadlock issue in ocfs2_dio_end_io_write()
...
Linus Torvalds [Fri, 25 Mar 2016 23:55:37 +0000 (16:55 -0700)]
Merge tag 'pm+acpi-4.6-rc1-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management fixlet from Rafael Wysocki:
"One of commits in my previous pull request changed the permissions of
drivers/power/avs/rockchip-io-domain.c to executable by mistake"
* tag 'pm+acpi-4.6-rc1-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
Fix permissions of drivers/power/avs/rockchip-io-domain.c
Linus Torvalds [Fri, 25 Mar 2016 23:39:05 +0000 (16:39 -0700)]
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
Pull more input updates from Dmitry Torokhov:
"Second round of updates for the input subsystem.
The BYD PS/2 protocol driver now uses absolute reporting mode and
should behave more like other touchpads; Synaptics driver needed to
extend one of its quirks to a newer firmware version, and a few USB
drivers got tightened up checks for the contents of their descriptors"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
Input: sur40 - fix DMA on stack
Input: ati_remote2 - fix crashes on detecting device with invalid descriptor
Input: synaptics - handle spurious release of trackstick buttons, again
Input: synaptics-rmi4 - remove check of Non-NULL array
Input: byd - enable absolute mode
Input: ims-pcu - sanity check against missing interfaces
Input: melfas_mip4 - add hw_version sysfs attribute
Nicolai Stange [Fri, 25 Mar 2016 21:22:14 +0000 (14:22 -0700)]
mm/filemap: generic_file_read_iter(): check for zero reads unconditionally
If
- generic_file_read_iter() gets called with a zero read length,
- the read offset is at a page boundary,
- IOCB_DIRECT is not set
- and the page in question hasn't made it into the page cache yet,
then do_generic_file_read() will trigger a readahead with a req_size hint
of zero.
Since roundup_pow_of_two(0) is undefined, UBSAN reports
UBSAN: Undefined behaviour in include/linux/log2.h:63:13
shift exponent 64 is too large for 64-bit type 'long unsigned int'
CPU: 3 PID: 1017 Comm: sa1 Tainted: G L 4.5.0-next-20160318+ #14
[...]
Call Trace:
[...]
[<ffffffff813ef61a>] ondemand_readahead+0x3aa/0x3d0
[<ffffffff813ef61a>] ? ondemand_readahead+0x3aa/0x3d0
[<ffffffff813c73bd>] ? find_get_entry+0x2d/0x210
[<ffffffff813ef9c3>] page_cache_sync_readahead+0x63/0xa0
[<ffffffff813cc04d>] do_generic_file_read+0x80d/0xf90
[<ffffffff813cc955>] generic_file_read_iter+0x185/0x420
[...]
[<ffffffff81510b06>] __vfs_read+0x256/0x3d0
[...]
when get_init_ra_size() gets called from ondemand_readahead().
The net effect is that the initial readahead size is arch dependent for
requested read lengths of zero: for example, since
1UL << (sizeof(unsigned long) * 8)
evaluates to 1 on x86 while its result is 0 on ARMv7, the initial readahead
size becomes 4 on the former and 0 on the latter.
What's more, whether or not the file access timestamp is updated for zero
length reads is decided differently for the two cases of IOCB_DIRECT
being set or cleared: in the first case, generic_file_read_iter()
explicitly skips updating that timestamp while in the latter case, it is
always updated through the call to do_generic_file_read().
According to POSIX, zero length reads "do not modify the last data access
timestamp" and thus, the IOCB_DIRECT behaviour is POSIXly correct.
Let generic_file_read_iter() unconditionally check the requested read
length at its entry and return immediately with success if it is zero.
Signed-off-by: Nicolai Stange <nicstange@gmail.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mm, kasan: stackdepot implementation. Enable stackdepot for SLAB
Implement the stack depot and provide CONFIG_STACKDEPOT. Stack depot
will allow KASAN store allocation/deallocation stack traces for memory
chunks. The stack traces are stored in a hash table and referenced by
handles which reside in the kasan_alloc_meta and kasan_free_meta
structures in the allocated memory chunks.
IRQ stack traces are cut below the IRQ entry point to avoid unnecessary
duplication.
Right now stackdepot support is only enabled in SLAB allocator. Once
KASAN features in SLAB are on par with those in SLUB we can switch SLUB
to stackdepot as well, thus removing the dependency on SLUB stack
bookkeeping, which wastes a lot of memory.
This patch is based on the "mm: kasan: stack depots" patch originally
prepared by Dmitry Chernenkov.
Joonsoo has said that he plans to reuse the stackdepot code for the
mm/page_owner.c debugging facility.
[akpm@linux-foundation.org: s/depot_stack_handle/depot_stack_handle_t]
[aryabinin@virtuozzo.com: comment style fixes] Signed-off-by: Alexander Potapenko <glider@google.com> Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Andrey Konovalov <adech.fo@gmail.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Konstantin Serebryany <kcc@google.com> Cc: Dmitry Chernenkov <dmitryc@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
arch, ftrace: for KASAN put hard/soft IRQ entries into separate sections
KASAN needs to know whether the allocation happens in an IRQ handler.
This lets us strip everything below the IRQ entry point to reduce the
number of unique stack traces needed to be stored.
Move the definition of __irq_entry to <linux/interrupt.h> so that the
users don't need to pull in <linux/ftrace.h>. Also introduce the
__softirq_entry macro which is similar to __irq_entry, but puts the
corresponding functions to the .softirqentry.text section.
Signed-off-by: Alexander Potapenko <glider@google.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Andrey Konovalov <adech.fo@gmail.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Konstantin Serebryany <kcc@google.com> Cc: Dmitry Chernenkov <dmitryc@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Unlike SLUB, SLAB doesn't store allocation/deallocation stacks for heap
objects, therefore we reimplement this feature in mm/kasan/stackdepot.c.
The intention is to ultimately switch SLUB to use this implementation as
well, which will save a lot of memory (right now SLUB bloats each object
by 256 bytes to store the allocation/deallocation stacks).
Also neither SLUB nor SLAB delay the reuse of freed memory chunks, which
is necessary for better detection of use-after-free errors. We
introduce memory quarantine (mm/kasan/quarantine.c), which allows
delayed reuse of deallocated memory.
This patch (of 7):
Rename kmalloc_large_oob_right() to kmalloc_pagealloc_oob_right(), as
the test only checks the page allocator functionality. Also reimplement
kmalloc_large_oob_right() so that the test allocates a large enough
chunk of memory that still does not trigger the page allocator fallback.
Signed-off-by: Alexander Potapenko <glider@google.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Andrey Konovalov <adech.fo@gmail.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Konstantin Serebryany <kcc@google.com> Cc: Dmitry Chernenkov <dmitryc@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Vlastimil Babka [Fri, 25 Mar 2016 21:21:50 +0000 (14:21 -0700)]
mm/page_alloc: prevent merging between isolated and other pageblocks
Hanjun Guo has reported that a CMA stress test causes broken accounting of
CMA and free pages:
> Before the test, I got:
> -bash-4.3# cat /proc/meminfo | grep Cma
> CmaTotal: 204800 kB
> CmaFree: 195044 kB
>
>
> After running the test:
> -bash-4.3# cat /proc/meminfo | grep Cma
> CmaTotal: 204800 kB
> CmaFree: 6602584 kB
>
> So the freed CMA memory is more than total..
>
> Also the the MemFree is more than mem total:
>
> -bash-4.3# cat /proc/meminfo
> MemTotal: 16342016 kB
> MemFree: 22367268 kB
> MemAvailable: 22370528 kB
Laura Abbott has confirmed the issue and suspected the freepage accounting
rewrite around 3.18/4.0 by Joonsoo Kim. Joonsoo had a theory that this is
caused by unexpected merging between MIGRATE_ISOLATE and MIGRATE_CMA
pageblocks:
> CMA isolates MAX_ORDER aligned blocks, but, during the process,
> partialy isolated block exists. If MAX_ORDER is 11 and
> pageblock_order is 9, two pageblocks make up MAX_ORDER
> aligned block and I can think following scenario because pageblock
> (un)isolation would be done one by one.
>
> (each character means one pageblock. 'C', 'I' means MIGRATE_CMA,
> MIGRATE_ISOLATE, respectively.
>
> CC -> IC -> II (Isolation)
> II -> CI -> CC (Un-isolation)
>
> If some pages are freed at this intermediate state such as IC or CI,
> that page could be merged to the other page that is resident on
> different type of pageblock and it will cause wrong freepage count.
This was supposed to be prevented by CMA operating on MAX_ORDER blocks,
but since it doesn't hold the zone->lock between pageblocks, a race
window does exist.
It's also likely that unexpected merging can occur between
MIGRATE_ISOLATE and non-CMA pageblocks. This should be prevented in
__free_one_page() since commit 3c605096d315 ("mm/page_alloc: restrict
max order of merging on isolated pageblock"). However, we only check
the migratetype of the pageblock where buddy merging has been initiated,
not the migratetype of the buddy pageblock (or group of pageblocks)
which can be MIGRATE_ISOLATE.
Joonsoo has suggested checking for buddy migratetype as part of
page_is_buddy(), but that would add extra checks in allocator hotpath
and bloat-o-meter has shown significant code bloat (the function is
inline).
This patch reduces the bloat at some expense of more complicated code.
The buddy-merging while-loop in __free_one_page() is initially bounded
to pageblock_border and without any migratetype checks. The checks are
placed outside, bumping the max_order if merging is allowed, and
returning to the while-loop with a statement which can't be possibly
considered harmful.
This fixes the accounting bug and also removes the arguably weird state
in the original commit 3c605096d315 where buddies could be left
unmerged.
Fixes: 3c605096d315 ("mm/page_alloc: restrict max order of merging on isolated pageblock") Link: https://lkml.org/lkml/2016/3/2/280 Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Reported-by: Hanjun Guo <guohanjun@huawei.com> Tested-by: Hanjun Guo <guohanjun@huawei.com> Acked-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Debugged-by: Laura Abbott <labbott@redhat.com> Debugged-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: "Kirill A. Shutemov" <kirill@shutemov.name> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com> Cc: <stable@vger.kernel.org> [3.18+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Arnd Bergmann [Fri, 25 Mar 2016 21:21:47 +0000 (14:21 -0700)]
drivers/memstick/host/r592.c: avoid gcc-6 warning
The r592 driver relies on behavior of the DMA mapping API that is
normally observed but not guaranteed by the API. Instead it uses a
runtime check to fail transfers if the API ever behaves
When CONFIG_NEED_SG_DMA_LENGTH is not set, one of the checks turns into a
comparison of a variable with itself, which gcc-6.0 now warns about:
drivers/memstick/host/r592.c: In function 'r592_transfer_fifo_dma':
drivers/memstick/host/r592.c:302:31: error: self-comparison always evaluates to false [-Werror=tautological-compare]
(sg_dma_len(&dev->req->sg) < dev->req->sg.length)) {
^
The check itself is not a problem, so this patch just rephrases the
condition in a way that gcc does not consider an indication of a mistake.
We already know that dev->req->sg.length was initially R592_LFIFO_SIZE, so
we can compare it to that constant again.
Xue jiufei [Fri, 25 Mar 2016 21:21:44 +0000 (14:21 -0700)]
ocfs2: extend enough credits for freeing one truncate record while replaying truncate records
Now function ocfs2_replay_truncate_records() first modifies tl_used,
then calls ocfs2_extend_trans() to extend transactions for gd and alloc
inode used for freeing clusters. jbd2_journal_restart() may be called
and it may happen that tl_used in truncate log is decreased but the
clusters are not freed, which means these clusters are lost. So we
should avoid extending transactions in these two operations.
Signed-off-by: joyce.xue <xuejiufei@huawei.com> Reviewed-by: Mark Fasheh <mfasheh@suse.de> Acked-by: Joseph Qi <joseph.qi@huawei.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Junxiao Bi <junxiao.bi@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Xue jiufei [Fri, 25 Mar 2016 21:21:41 +0000 (14:21 -0700)]
ocfs2: extend transaction for ocfs2_remove_rightmost_path() and ocfs2_update_edge_lengths() before to avoid inconsistency between inode and et
I found that jbd2_journal_restart() is called in some places without
keeping things consistently before. However, jbd2_journal_restart() may
commit the handle's transaction and restart another one. If the first
transaction is committed successfully while another not, it may cause
filesystem inconsistency or read only. This is an effort to fix this
kind of problems.
This patch (of 3):
The following functions will be called while truncating an extent:
ocfs2_remove_btree_range
-> ocfs2_start_trans
-> ocfs2_remove_extent
-> ocfs2_truncate_rec
-> ocfs2_extend_rotate_transaction
-> jbd2_journal_restart if jbd2_journal_extend fail
-> ocfs2_rotate_tree_left
-> ocfs2_remove_rightmost_path
-> ocfs2_extend_rotate_transaction
-> ocfs2_unlink_subtree
-> ocfs2_update_edge_lengths
-> ocfs2_extend_trans
-> jbd2_journal_restart if jbd2_journal_extend fail
-> ocfs2_et_update_clusters
-> ocfs2_commit_trans
jbd2_journal_restart() may be called and it may happened that the buffers
dirtied in ocfs2_truncate_rec() are committed while buffers dirtied in
ocfs2_et_update_clusters() are not, the total clusters on extent tree and
i_clusters in ocfs2_dinode is inconsistency. So the clusters got from
ocfs2_dinode is incorrect, and it also cause read-only problem when call
ocfs2_commit_truncate() with the error message: "Inode %llu has empty
extent block at %llu".
We should extend enough credits for function ocfs2_remove_rightmost_path
and ocfs2_update_edge_lengths to avoid this inconsistency.
Signed-off-by: joyce.xue <xuejiufei@huawei.com> Acked-by: Joseph Qi <joseph.qi@huawei.com> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
xuejiufei [Fri, 25 Mar 2016 21:21:38 +0000 (14:21 -0700)]
ocfs2/dlm: move lock to the tail of grant queue while doing in-place convert
We have found a bug when two nodes doing umount one after another.
1) Node 1 migrate a lockres that has 3 locks in grant queue such as
N2(PR)<->N3(NL)<->N4(PR) to N2. After migration, lvb of the lock
N3(NL) and N4(PR) are empty on node 2 because migration target do not
copy lvb to these two lock.
2) Node 3 want to convert to PR, it can be granted in
__dlmconvert_master(), and the order of these locks is unchanged. The
lvb of the lock N3(PR) on node 2 is copyed from lockres in function
dlm_update_lvb() while the lvb of lock N4(PR) is still empty.
3) Node 2 want to leave domain, it will migrate this lockres to node 3.
Then node 2 will trigger the BUG in dlm_prepare_lvb_for_migration()
when adding the lock N4(PR) to mres with the following message because
the lvb of mres is already copied from lock N3(PR), but the lvb of lock
N4(PR) is empty.
"Mismatched lvb in lock cookie=%u:%llu, name=%.*s, node=%u"
[akpm@linux-foundation.org: tweak comment] Signed-off-by: xuejiufei <xuejiufei@huawei.com> Acked-by: Joseph Qi <joseph.qi@huawei.com> Cc: Mark Fasheh <mfasheh@suse.de> Cc: Joel Becker <jlbec@evilplan.org> Cc: Junxiao Bi <junxiao.bi@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
jiangyiwen [Fri, 25 Mar 2016 21:21:35 +0000 (14:21 -0700)]
ocfs2: solve a problem of crossing the boundary in updating backups
In update_backups() there exists a problem of crossing the boundary as
follows:
we assume that lun will be resized to 1TB(cluster_size is 32kb), it will
include 0~33554431 cluster, in update_backups func, it will backup super
block in location of 1TB which is the 33554432th cluster, so the
phenomenon of crossing the boundary happens.
Signed-off-by: Yiwen Jiang <jiangyiwen@huawei.com> Reviewed-by: Joseph Qi <joseph.qi@huawei.com> Cc: Xue jiufei <xuejiufei@huawei.com> Cc: Mark Fasheh <mfasheh@suse.de> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
jiangyiwen [Fri, 25 Mar 2016 21:21:32 +0000 (14:21 -0700)]
ocfs2: fix occurring deadlock by changing ocfs2_wq from global to local
This patch fixes a deadlock, as follows:
Node 1 Node 2 Node 3
1)volume a and b are only mount vol a only mount vol b
mounted
2) start to mount b start to mount a
3) check hb of Node 3 check hb of Node 2
in vol a, qs_holds++ in vol b, qs_holds++
4) -------------------- all nodes' network down --------------------
5) progress of mount b the same situation as
failed, and then call Node 2
ocfs2_dismount_volume.
but the process is hung,
since there is a work
in ocfs2_wq cannot beo
completed. This work is
about vol a, because
ocfs2_wq is global wq.
BTW, this work which is
scheduled in ocfs2_wq is
ocfs2_orphan_scan_work,
and the context in this work
needs to take inode lock
of orphan_dir, because
lockres owner are Node 1 and
all nodes' nework has been down
at the same time, so it can't
get the inode lock.
6) Why can't this node be fenced
when network disconnected?
Because the process of
mount is hung what caused qs_holds
is not equal 0.
Because all works in the ocfs2_wq are relative to the super block.
The solution is to change the ocfs2_wq from global to local. In other
words, move it into struct ocfs2_super.
Signed-off-by: Yiwen Jiang <jiangyiwen@huawei.com> Reviewed-by: Joseph Qi <joseph.qi@huawei.com> Cc: Xue jiufei <xuejiufei@huawei.com> Cc: Mark Fasheh <mfasheh@suse.de> Cc: Joel Becker <jlbec@evilplan.org> Cc: Cc: Junxiao Bi <junxiao.bi@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Joseph Qi [Fri, 25 Mar 2016 21:21:29 +0000 (14:21 -0700)]
ocfs2/dlm: fix BUG in dlm_move_lockres_to_recovery_list
When master handles convert request, it queues ast first and then
returns status. This may happen that the ast is sent before the request
status because the above two messages are sent by two threads. And
right after the ast is sent, if master down, it may trigger BUG in
dlm_move_lockres_to_recovery_list in the requested node because ast
handler moves it to grant list without clear lock->convert_pending. So
remove BUG_ON statement and check if the ast is processed in
dlmconvert_remote.
Signed-off-by: Joseph Qi <joseph.qi@huawei.com> Reported-by: Yiwen Jiang <jiangyiwen@huawei.com> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Mark Fasheh <mfasheh@suse.de> Cc: Joel Becker <jlbec@evilplan.org> Cc: Tariq Saeed <tariq.x.saeed@oracle.com> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Joseph Qi [Fri, 25 Mar 2016 21:21:26 +0000 (14:21 -0700)]
ocfs2/dlm: fix race between convert and recovery
There is a race window between dlmconvert_remote and
dlm_move_lockres_to_recovery_list, which will cause a lock with
OCFS2_LOCK_BUSY in grant list, thus system hangs.
status = dlm_send_remote_convert_request();
>>>>>> race window, master has queued ast and return DLM_NORMAL,
and then down before sending ast.
this node detects master down and calls
dlm_move_lockres_to_recovery_list, which will revert the
lock to grant list.
Then OCFS2_LOCK_BUSY won't be cleared as new master won't
send ast any more because it thinks already be authorized.
In this case, check if res->state has DLM_LOCK_RES_RECOVERING bit set
(res is still in recovering) or res master changed (new master has
finished recovery), reset the status to DLM_RECOVERING, then it will
retry convert.
Signed-off-by: Joseph Qi <joseph.qi@huawei.com> Reported-by: Yiwen Jiang <jiangyiwen@huawei.com> Reviewed-by: Junxiao Bi <junxiao.bi@oracle.com> Cc: Mark Fasheh <mfasheh@suse.de> Cc: Joel Becker <jlbec@evilplan.org> Cc: Tariq Saeed <tariq.x.saeed@oracle.com> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ryan Ding [Fri, 25 Mar 2016 21:21:23 +0000 (14:21 -0700)]
ocfs2: fix a deadlock issue in ocfs2_dio_end_io_write()
The code should call ocfs2_free_alloc_context() to free meta_ac &
data_ac before calling ocfs2_run_deallocs(). Because
ocfs2_run_deallocs() will acquire the system inode's i_mutex hold by
meta_ac. So try to release the lock before ocfs2_run_deallocs().
Fixes: af1310367f41 ("ocfs2: fix sparse file & data ordering issue in direct io.") Signed-off-by: Ryan Ding <ryan.ding@oracle.com> Acked-by: Junxiao Bi <junxiao.bi@oracle.com> Cc: Joseph Qi <joseph.qi@huawei.com> Cc: Mark Fasheh <mfasheh@suse.de> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ryan Ding [Fri, 25 Mar 2016 21:21:20 +0000 (14:21 -0700)]
ocfs2: fix disk file size and memory file size mismatch
When doing append direct write in an already allocated cluster, and fast
path in ocfs2_dio_get_block() is triggered, function
ocfs2_dio_end_io_write() will be skipped as there is no context
allocated.
As a result, the disk file size will not be changed as it should be.
The solution is to skip fast path when we are about to change file size.
Fixes: af1310367f41 ("ocfs2: fix sparse file & data ordering issue in direct io.") Signed-off-by: Ryan Ding <ryan.ding@oracle.com> Acked-by: Junxiao Bi <junxiao.bi@oracle.com> Cc: Joseph Qi <joseph.qi@huawei.com> Cc: Mark Fasheh <mfasheh@suse.de> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ryan Ding [Fri, 25 Mar 2016 21:21:18 +0000 (14:21 -0700)]
ocfs2: take ip_alloc_sem in ocfs2_dio_get_block & ocfs2_dio_end_io_write
Take ip_alloc_sem to prevent concurrent access to extent tree, which may
cause the extent tree in an unstable state.
Signed-off-by: Ryan Ding <ryan.ding@oracle.com> Reviewed-by: Junxiao Bi <junxiao.bi@oracle.com> Cc: Joseph Qi <joseph.qi@huawei.com> Cc: Mark Fasheh <mfasheh@suse.de> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ryan Ding [Fri, 25 Mar 2016 21:21:15 +0000 (14:21 -0700)]
ocfs2: fix ip_unaligned_aio deadlock with dio work queue
In the current implementation of unaligned aio+dio, lock order behave as
follow:
in user process context:
-> call io_submit()
-> get i_mutex
<== window1
-> get ip_unaligned_aio
-> submit direct io to block device
-> release i_mutex
-> io_submit() return
in dio work queue context(the work queue is created in __blockdev_direct_IO):
-> release ip_unaligned_aio
<== window2
-> get i_mutex
-> clear unwritten flag & change i_size
-> release i_mutex
There is a limitation to the thread number of dio work queue. 256 at
default. If all 256 thread are in the above 'window2' stage, and there
is a user process in the 'window1' stage, the system will became
deadlock. Since the user process hold i_mutex to wait ip_unaligned_aio
lock, while there is a direct bio hold ip_unaligned_aio mutex who is
waiting for a dio work queue thread to be schedule. But all the dio
work queue thread is waiting for i_mutex lock in 'window2'.
This case only happened in a test which send a large number(more than
256) of aio at one io_submit() call.
My design is to remove ip_unaligned_aio lock. Change it to a sync io
instead. Just like ip_unaligned_aio lock, serialize the unaligned aio
dio.
[akpm@linux-foundation.org: remove OCFS2_IOCB_UNALIGNED_IO, per Junxiao Bi] Signed-off-by: Ryan Ding <ryan.ding@oracle.com> Reviewed-by: Junxiao Bi <junxiao.bi@oracle.com> Cc: Joseph Qi <joseph.qi@huawei.com> Cc: Mark Fasheh <mfasheh@suse.de> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ryan Ding [Fri, 25 Mar 2016 21:21:12 +0000 (14:21 -0700)]
ocfs2: code clean up for direct io
Clean up ocfs2_file_write_iter & ocfs2_prepare_inode_for_write:
* remove append dio check: it will be checked in ocfs2_direct_IO()
* remove file hole check: file hole is supported for now
* remove inline data check: it will be checked in ocfs2_direct_IO()
* remove the full_coherence check when append dio: we will get the
inode_lock in ocfs2_dio_get_block, there is no need to fall back to
buffer io to ensure the coherence semantics.
Now the drop dio procedure is gone. :)
[akpm@linux-foundation.org: remove unused label] Signed-off-by: Ryan Ding <ryan.ding@oracle.com> Reviewed-by: Junxiao Bi <junxiao.bi@oracle.com> Cc: Joseph Qi <joseph.qi@huawei.com> Cc: Mark Fasheh <mfasheh@suse.de> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ryan Ding [Fri, 25 Mar 2016 21:21:09 +0000 (14:21 -0700)]
ocfs2: fix sparse file & data ordering issue in direct io
There are mainly three issues in the direct io code path after commit 24c40b329e03 ("ocfs2: implement ocfs2_direct_IO_write"):
* Does not support sparse file.
* Does not support data ordering. eg: when write to a file hole, it
will alloc extent first. If system crashed before io finished, data
will corrupt.
* Potential risk when doing aio+dio. The -EIOCBQUEUED return value is
likely to be ignored by ocfs2_direct_IO_write().
To resolve above problems, re-design direct io code with following ideas:
* Use buffer io to fill in holes. And this will make better
performance also.
* Clear unwritten after direct write finished. So we can make sure
meta data changes after data write to disk. (Unwritten extent is
invisible to user, from user's view, meta data is not changed when
allocate an unwritten extent.)
* Clear ocfs2_direct_IO_write(). Do all ending work in end_io.
This patch has passed fs,dio,ltp-aiodio.part1,ltp-aiodio.part2,ltp-aiodio.part4
test cases of ltp.
For performance improvement, see following test result:
ocfs2 cluster size 1MB, ocfs2 volume is mounted on /mnt/.
The original way:
+ rm /mnt/test.img -f
+ dd if=/dev/zero of=/mnt/test.img bs=4K count=1048576 oflag=direct 1048576+0 records in 1048576+0 records out 4294967296 bytes (4.3 GB) copied, 1707.83 s, 2.5 MB/s
+ rm /mnt/test.img -f
+ dd if=/dev/zero of=/mnt/test.img bs=256K count=16384 oflag=direct
16384+0 records in
16384+0 records out 4294967296 bytes (4.3 GB) copied, 582.705 s, 7.4 MB/s
After this patch:
+ rm /mnt/test.img -f
+ dd if=/dev/zero of=/mnt/test.img bs=4K count=1048576 oflag=direct 1048576+0 records in 1048576+0 records out 4294967296 bytes (4.3 GB) copied, 64.6412 s, 66.4 MB/s
+ rm /mnt/test.img -f
+ dd if=/dev/zero of=/mnt/test.img bs=256K count=16384 oflag=direct
16384+0 records in
16384+0 records out 4294967296 bytes (4.3 GB) copied, 34.7611 s, 124 MB/s
Signed-off-by: Ryan Ding <ryan.ding@oracle.com> Reviewed-by: Junxiao Bi <junxiao.bi@oracle.com> Cc: Joseph Qi <joseph.qi@huawei.com> Cc: Mark Fasheh <mfasheh@suse.de> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ryan Ding [Fri, 25 Mar 2016 21:21:06 +0000 (14:21 -0700)]
ocfs2: record UNWRITTEN extents when populate write desc
To support direct io in ocfs2_write_begin_nolock & ocfs2_write_end_nolock.
There is still one issue in the direct write procedure.
phase 1: alloc extent with UNWRITTEN flag
phase 2: submit direct data to disk, add zero page to page cache
phase 3: clear UNWRITTEN flag when data has been written to disk
When there are 2 direct write A(0~3KB),B(4~7KB) writing to the same
cluster 0~7KB (cluster size 8KB). Write request A arrive phase 2 first,
it will zero the region (4~7KB). Before request A enter to phase 3,
request B arrive phase 2, it will zero region (0~3KB). This is just like
request B steps request A.
To resolve this issue, we should let request B knows this cluster is already
under zero, to prevent it from steps the previous write request.
This patch will add function ocfs2_unwritten_check() to do this job. It
will record all clusters that are under direct write(it will be recorded
in the 'ip_unwritten_list' member of inode info), and prevent the later
direct write writing to the same cluster to do the zero work again.
Signed-off-by: Ryan Ding <ryan.ding@oracle.com> Reviewed-by: Junxiao Bi <junxiao.bi@oracle.com> Cc: Joseph Qi <joseph.qi@huawei.com> Cc: Mark Fasheh <mfasheh@suse.de> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ryan Ding [Fri, 25 Mar 2016 21:21:03 +0000 (14:21 -0700)]
ocfs2: return the physical address in ocfs2_write_cluster
To support direct io in ocfs2_write_begin_nolock & ocfs2_write_end_nolock.
Direct io needs to get the physical address from write_begin, to map the
user page. This patch is to change the arg 'phys' of
ocfs2_write_cluster to a pointer, so it can be retrieved to write_begin.
And we can retrieve it to the direct io procedure.
Signed-off-by: Ryan Ding <ryan.ding@oracle.com> Reviewed-by: Junxiao Bi <junxiao.bi@oracle.com> Cc: Joseph Qi <joseph.qi@huawei.com> Cc: Mark Fasheh <mfasheh@suse.de> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ryan Ding [Fri, 25 Mar 2016 21:21:01 +0000 (14:21 -0700)]
ocfs2: do not change i_size in write_end for direct io
To support direct io in ocfs2_write_begin_nolock & ocfs2_write_end_nolock.
Append direct io do not change i_size in get block phase. It only move
to orphan when starting write. After data is written to disk, it will
delete itself from orphan and update i_size. So skip i_size change
section in write_begin for direct io.
And when there is no extents alloc, no meta data changes needed for
direct io (since write_begin start trans for 2 reason: alloc extents &
change i_size. Now none of them needed). So we can skip start trans
procedure.
Signed-off-by: Ryan Ding <ryan.ding@oracle.com> Reviewed-by: Junxiao Bi <junxiao.bi@oracle.com> Cc: Joseph Qi <joseph.qi@huawei.com> Cc: Mark Fasheh <mfasheh@suse.de> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ryan Ding [Fri, 25 Mar 2016 21:20:58 +0000 (14:20 -0700)]
ocfs2: test target page before change it
To support direct io in ocfs2_write_begin_nolock & ocfs2_write_end_nolock.
Direct io data will not appear in buffer. The w_target_page member will
not be filled by direct io. So avoid to use it when it's NULL. Unlinke
buffer io and mmap, direct io will call write_begin with more than 1
page a time. So the target_index is not sufficient to describe the
actual data. change it to a range start at target_index, end in
end_index.
Signed-off-by: Ryan Ding <ryan.ding@oracle.com> Reviewed-by: Junxiao Bi <junxiao.bi@oracle.com> Cc: Joseph Qi <joseph.qi@huawei.com> Cc: Mark Fasheh <mfasheh@suse.de> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ryan Ding [Fri, 25 Mar 2016 21:20:55 +0000 (14:20 -0700)]
ocfs2: use c_new to indicate newly allocated extents
To support direct io in ocfs2_write_begin_nolock & ocfs2_write_end_nolock.
There is a problem in ocfs2's direct io implement: if system crashed
after extents allocated, and before data return, we will get a extent
with dirty data on disk. This problem violate the journal=order
semantics, which means meta changes take effect after data written to
disk. To resolve this issue, direct write can use the UNWRITTEN flag to
describe a extent during direct data writeback. The direct write
procedure should act in the following order:
phase 1: alloc extent with UNWRITTEN flag
phase 2: submit direct data to disk, add zero page to page cache
phase 3: clear UNWRITTEN flag when data has been written to disk
This patch is to change the 'c_unwritten' member of
ocfs2_write_cluster_desc to 'c_clear_unwritten'. Means whether to clear
the unwritten flag. It do not care if a extent is allocated or not.
And use 'c_new' to specify a newly allocated extent. So the direct io
procedure can use c_clear_unwritten to control the UNWRITTEN bit on
extent.
Signed-off-by: Ryan Ding <ryan.ding@oracle.com> Reviewed-by: Junxiao Bi <junxiao.bi@oracle.com> Cc: Joseph Qi <joseph.qi@huawei.com> Cc: Mark Fasheh <mfasheh@suse.de> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ryan Ding [Fri, 25 Mar 2016 21:20:52 +0000 (14:20 -0700)]
ocfs2: add ocfs2_write_type_t type to identify the caller of write
Patchset: fix ocfs2 direct io code patch to support sparse file and data
ordering semantics
The idea is to use buffer io(more precisely use the interface
ocfs2_write_begin_nolock & ocfs2_write_end_nolock) to do the zero work
beyond block size. And clear UNWRITTEN flag until direct io data has
been written to disk, which can prevent data corruption when system
crashed during direct write.
And we will also archive a better performance: eg. dd direct write new
file with block size 4KB: before this patchset:
2.5 MB/s
after this patchset:
66.4 MB/s
This patch (of 8):
To support direct io in ocfs2_write_begin_nolock &
ocfs2_write_end_nolock.
Remove unused args filp & flags. Add new arg type. The type is one of
buffer/direct/mmap. Indicate 3 way to perform write. buffer/mmap type
has implemented. direct type will be implemented later.
Signed-off-by: Ryan Ding <ryan.ding@oracle.com> Reviewed-by: Junxiao Bi <junxiao.bi@oracle.com> Cc: Joseph Qi <joseph.qi@huawei.com> Cc: Mark Fasheh <mfasheh@suse.de> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Andrew Morton [Fri, 25 Mar 2016 21:20:47 +0000 (14:20 -0700)]
drivers/input: eliminate INPUT_COMPAT_TEST macro
INPUT_COMPAT_TEST became much simpler after commit f4056b52845283
("input: redefine INPUT_COMPAT_TEST as in_compat_syscall()") so we can
cleanly eliminate it altogether.
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andy Lutomirski <luto@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Tetsuo Handa [Fri, 25 Mar 2016 21:20:44 +0000 (14:20 -0700)]
oom, oom_reaper: protect oom_reaper_list using simpler way
"oom, oom_reaper: disable oom_reaper for oom_kill_allocating_task" tried
to protect oom_reaper_list using MMF_OOM_KILLED flag. But we can do it
by simply checking tsk->oom_reaper_list != NULL.
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Michal Hocko [Fri, 25 Mar 2016 21:20:41 +0000 (14:20 -0700)]
oom: make oom_reaper freezable
After "oom: clear TIF_MEMDIE after oom_reaper managed to unmap the
address space" oom_reaper will call exit_oom_victim on the target task
after it is done. This might however race with the PM freezer:
which breaks the oom_killer_disable semantic. We no longer have a
guarantee that the oom victim won't interfere with the freezer because
it might be anywhere on the way to do_exit while the freezer thinks the
task has already terminated. It might trigger IO or touch devices which
are frozen already.
In order to close this race, make the oom_reaper thread freezable. This
will work because
a) already running oom_reaper will block freezer to enter the
quiescent state
b) wake_oom_reaper will not wake up the reaper after it has been
frozen
c) the only way to call exit_oom_victim after try_to_freeze_tasks
is from the oom victim's context when we know the further
interference shouldn't be possible
Signed-off-by: Michal Hocko <mhocko@suse.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: David Rientjes <rientjes@google.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Hugh Dickins <hughd@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>
Michal Hocko [Fri, 25 Mar 2016 21:20:36 +0000 (14:20 -0700)]
oom, oom_reaper: disable oom_reaper for oom_kill_allocating_task
Tetsuo has reported that oom_kill_allocating_task=1 will cause
oom_reaper_list corruption because oom_kill_process doesn't follow
standard OOM exclusion (aka ignores TIF_MEMDIE) and allows to enqueue
the same task multiple times - e.g. by sacrificing the same child
multiple times.
This patch fixes the issue by introducing a new MMF_OOM_KILLED mm flag
which is set in oom_kill_process atomically and oom reaper is disabled
if the flag was already set.
Signed-off-by: Michal Hocko <mhocko@suse.com> Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: David Rientjes <rientjes@google.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Hugh Dickins <hughd@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>
Michal Hocko [Fri, 25 Mar 2016 21:20:33 +0000 (14:20 -0700)]
mm, oom_reaper: implement OOM victims queuing
wake_oom_reaper has allowed only 1 oom victim to be queued. The main
reason for that was the simplicity as other solutions would require some
way of queuing. The current approach is racy and that was deemed
sufficient as the oom_reaper is considered a best effort approach to
help with oom handling when the OOM victim cannot terminate in a
reasonable time. The race could lead to missing an oom victim which can
get stuck
This race requires 2 OOM invocations in a short time period which is not
very likely but certainly not impossible. E.g. the original victim
might have not released a lot of memory for some reason.
The situation would improve considerably if wake_oom_reaper used a more
robust queuing. This is what this patch implements. This means adding
oom_reaper_list list_head into task_struct (eat a hole before embeded
thread_struct for that purpose) and a oom_reaper_lock spinlock for
queuing synchronization. wake_oom_reaper will then add the task on the
queue and oom_reaper will dequeue it.
Signed-off-by: Michal Hocko <mhocko@suse.com> Cc: Vladimir Davydov <vdavydov@virtuozzo.com> Cc: Andrea Argangeli <andrea@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Hugh Dickins <hughd@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Mel Gorman <mgorman@suse.de> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Rik van Riel <riel@redhat.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Michal Hocko [Fri, 25 Mar 2016 21:20:27 +0000 (14:20 -0700)]
oom: clear TIF_MEMDIE after oom_reaper managed to unmap the address space
When oom_reaper manages to unmap all the eligible vmas there shouldn't
be much of the freable memory held by the oom victim left anymore so it
makes sense to clear the TIF_MEMDIE flag for the victim and allow the
OOM killer to select another task.
The lack of TIF_MEMDIE also means that the victim cannot access memory
reserves anymore but that shouldn't be a problem because it would get
the access again if it needs to allocate and hits the OOM killer again
due to the fatal_signal_pending resp. PF_EXITING check. We can safely
hide the task from the OOM killer because it is clearly not a good
candidate anymore as everyhing reclaimable has been torn down already.
This patch will allow to cap the time an OOM victim can keep TIF_MEMDIE
and thus hold off further global OOM killer actions granted the oom
reaper is able to take mmap_sem for the associated mm struct. This is
not guaranteed now but further steps should make sure that mmap_sem for
write should be blocked killable which will help to reduce such a lock
contention. This is not done by this patch.
Note that exit_oom_victim might be called on a remote task from
__oom_reap_task now so we have to check and clear the flag atomically
otherwise we might race and underflow oom_victims or wake up waiters too
early.
Signed-off-by: Michal Hocko <mhocko@suse.com> Suggested-by: Johannes Weiner <hannes@cmpxchg.org> Suggested-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Andrea Argangeli <andrea@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Hugh Dickins <hughd@google.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Oleg Nesterov <oleg@redhat.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>
Michal Hocko [Fri, 25 Mar 2016 21:20:24 +0000 (14:20 -0700)]
mm, oom: introduce oom reaper
This patch (of 5):
This is based on the idea from Mel Gorman discussed during LSFMM 2015
and independently brought up by Oleg Nesterov.
The OOM killer currently allows to kill only a single task in a good
hope that the task will terminate in a reasonable time and frees up its
memory. Such a task (oom victim) will get an access to memory reserves
via mark_oom_victim to allow a forward progress should there be a need
for additional memory during exit path.
It has been shown (e.g. by Tetsuo Handa) that it is not that hard to
construct workloads which break the core assumption mentioned above and
the OOM victim might take unbounded amount of time to exit because it
might be blocked in the uninterruptible state waiting for an event (e.g.
lock) which is blocked by another task looping in the page allocator.
This patch reduces the probability of such a lockup by introducing a
specialized kernel thread (oom_reaper) which tries to reclaim additional
memory by preemptively reaping the anonymous or swapped out memory owned
by the oom victim under an assumption that such a memory won't be needed
when its owner is killed and kicked from the userspace anyway. There is
one notable exception to this, though, if the OOM victim was in the
process of coredumping the result would be incomplete. This is
considered a reasonable constrain because the overall system health is
more important than debugability of a particular application.
A kernel thread has been chosen because we need a reliable way of
invocation so workqueue context is not appropriate because all the
workers might be busy (e.g. allocating memory). Kswapd which sounds
like another good fit is not appropriate as well because it might get
blocked on locks during reclaim as well.
oom_reaper has to take mmap_sem on the target task for reading so the
solution is not 100% because the semaphore might be held or blocked for
write but the probability is reduced considerably wrt. basically any
lock blocking forward progress as described above. In order to prevent
from blocking on the lock without any forward progress we are using only
a trylock and retry 10 times with a short sleep in between. Users of
mmap_sem which need it for write should be carefully reviewed to use
_killable waiting as much as possible and reduce allocations requests
done with the lock held to absolute minimum to reduce the risk even
further.
The API between oom killer and oom reaper is quite trivial.
wake_oom_reaper updates mm_to_reap with cmpxchg to guarantee only
NULL->mm transition and oom_reaper clear this atomically once it is done
with the work. This means that only a single mm_struct can be reaped at
the time. As the operation is potentially disruptive we are trying to
limit it to the ncessary minimum and the reaper blocks any updates while
it operates on an mm. mm_struct is pinned by mm_count to allow parallel
exit_mmap and a race is detected by atomic_inc_not_zero(mm_users).
Fix permissions of drivers/power/avs/rockchip-io-domain.c
The permissions of this file were modified by commit (f447671b9e4f PM /
AVS: rockchip-io: add io selectors and supplies for rk3399) by mistake,
so fix them.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
projects / linux-beck.git / log