Now sctp GSO uses skb_gro_receive() to append the data into head
skb frag_list. However it actually only needs very few code from
skb_gro_receive(). Besides, NAPI_GRO_CB has to be set while most
of its members are not needed here.
This patch is to add sctp_packet_gso_append() to build GSO frames
instead of skb_gro_receive(), and it would avoid many unnecessary
checks and make the code clearer.
Note that sctp will use page frags instead of frag_list to build
GSO frames in another patch. But it may take time, as sctp's GSO
frames may have different size. skb_segment() can only split it
into the frags with the same size, which would break the border
of sctp chunks.
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently, we use check_hlist() for garbage colleciton. However, we
use the ‘zone’ from the counted entry to query the existence of
existing entries in the hlist. This could be wrong when they are in
different zones, and this patch fixes this issue.
Fixes: e59ea3df3f ("netfilter: xt_connlimit: honor conntrack zone if available")
Signed-off-by: Yi-Hung Wei <yihung.wei@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
NFT_SET_EVAL is signalling the kernel that this sets can be updated from
the evaluation path, even if there are no expressions attached to the
element. Otherwise, set updates with no expressions fail. Update
description to describe the right semantics.
Fixes: 22fe54d5fe ("netfilter: nf_tables: add support for dynamic set updates")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
While hacking on kTLS, I ran into the following panic from an
unprivileged netserver / netperf TCP session:
BUG: unable to handle kernel NULL pointer dereference at 0000000000000000
PGD 800000037f378067 P4D 800000037f378067 PUD 3c0e61067 PMD 0
Oops: 0010 [#1] SMP KASAN PTI
CPU: 1 PID: 2289 Comm: netserver Not tainted 4.17.0+ #139
Hardware name: LENOVO 20FBCTO1WW/20FBCTO1WW, BIOS N1FET47W (1.21 ) 11/28/2016
RIP: 0010: (null)
Code: Bad RIP value.
RSP: 0018:ffff88036abcf740 EFLAGS: 00010246
RAX: dffffc0000000000 RBX: ffff88036f5f6800 RCX: 1ffff1006debed26
RDX: ffff88036abcf920 RSI: ffff8803cb1a4f00 RDI: ffff8803c258c280
RBP: ffff8803c258c280 R08: ffff8803c258c280 R09: ffffed006f559d48
R10: ffff88037aacea43 R11: ffffed006f559d49 R12: ffff8803c258c280
R13: ffff8803cb1a4f20 R14: 00000000000000db R15: ffffffffc168a350
FS: 00007f7e631f4700(0000) GS:ffff8803d1c80000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 00000003ccf64005 CR4: 00000000003606e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
? tls_sw_poll+0xa4/0x160 [tls]
? sock_poll+0x20a/0x680
? do_select+0x77b/0x11a0
? poll_schedule_timeout.constprop.12+0x130/0x130
? pick_link+0xb00/0xb00
? read_word_at_a_time+0x13/0x20
? vfs_poll+0x270/0x270
? deref_stack_reg+0xad/0xe0
? __read_once_size_nocheck.constprop.6+0x10/0x10
[...]
Debugging further, it turns out that calling into ctx->sk_poll() is
invalid since sk_poll itself is NULL which was saved from the original
TCP socket in order for tls_sw_poll() to invoke it.
Looks like the recent conversion from poll to poll_mask callback started
in 1525242310 ("net: add support for ->poll_mask in proto_ops") missed
to eventually convert kTLS, too: TCP's ->poll was converted over to the
->poll_mask in commit 2c7d3daceb ("net/tcp: convert to ->poll_mask")
and therefore kTLS wrongly saved the ->poll old one which is now NULL.
Convert kTLS over to use ->poll_mask instead. Also instead of POLLIN |
POLLRDNORM use the proper EPOLLIN | EPOLLRDNORM bits as the case in
tcp_poll_mask() as well that is mangled here.
Fixes: 2c7d3daceb ("net/tcp: convert to ->poll_mask")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dave Watson <davejwatson@fb.com>
Tested-by: Dave Watson <davejwatson@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pablo Neira Ayuso says:
====================
Netfilter/IPVS fixes for net
The following patchset contains Netfilter/IPVS fixes for your net tree:
1) Reject non-null terminated helper names from xt_CT, from Gao Feng.
2) Fix KASAN splat due to out-of-bound access from commit phase, from
Alexey Kodanev.
3) Missing conntrack hook registration on IPVS FTP helper, from Julian
Anastasov.
4) Incorrect skbuff allocation size in bridge nft_reject, from Taehee Yoo.
5) Fix inverted check on packet xmit to non-local addresses, also from
Julian.
6) Fix ebtables alignment compat problems, from Alin Nastac.
7) Hook mask checks are not correct in xt_set, from Serhey Popovych.
8) Fix timeout listing of element in ipsets, from Jozsef.
9) Cap maximum timeout value in ipset, also from Jozsef.
10) Don't allow family option for hash:mac sets, from Florent Fourcot.
11) Restrict ebtables to work with NFPROTO_BRIDGE targets only, this
Florian.
12) Another bug reported by KASAN in the rbtree set backend, from
Taehee Yoo.
13) Missing __IPS_MAX_BIT update doesn't include IPS_OFFLOAD_BIT.
From Gao Feng.
14) Missing initialization of match/target in ebtables, from Florian
Westphal.
15) Remove useless nft_dup.h file in include path, from C. Labbe.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull networking fixes from David Miller:
1) Fix several bpfilter/UMH bugs, in particular make the UMH build not
depend upon X86 specific Kconfig symbols. From Alexei Starovoitov.
2) Fix handling of modified context pointer in bpf verifier, from
Daniel Borkmann.
3) Kill regression in ifdown/ifup sequences for hv_netvsc driver, from
Dexuan Cui.
4) When the bonding primary member name changes, we have to re-evaluate
the bond->force_primary setting, from Xiangning Yu.
5) Eliminate possible padding beyone end of SKB in cdc_ncm driver, from
Bjørn Mork.
6) RX queue length reported for UDP sockets in procfs and socket diag
are inaccurate, from Paolo Abeni.
7) Fix br_fdb_find_port() locking, from Petr Machata.
8) Limit sk_rcvlowat values properly in TCP, from Soheil Hassas
Yeganeh.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (23 commits)
tcp: limit sk_rcvlowat by the maximum receive buffer
net: phy: dp83822: use BMCR_ANENABLE instead of BMSR_ANEGCAPABLE for DP83620
socket: close race condition between sock_close() and sockfs_setattr()
net: bridge: Fix locking in br_fdb_find_port()
udp: fix rx queue len reported by diag and proc interface
cdc_ncm: avoid padding beyond end of skb
net/sched: act_simple: fix parsing of TCA_DEF_DATA
net: fddi: fix a possible null-ptr-deref
net: aquantia: fix unsigned numvecs comparison with less than zero
net: stmmac: fix build failure due to missing COMMON_CLK dependency
bpfilter: fix race in pipe access
bpf, xdp: fix crash in xdp_umem_unaccount_pages
xsk: Fix umem fill/completion queue mmap on 32-bit
tools/bpf: fix selftest get_cgroup_id_user
bpfilter: fix OUTPUT_FORMAT
umh: fix race condition
net: mscc: ocelot: Fix uninitialized error in ocelot_netdevice_event()
bonding: re-evaluate force_primary when the primary slave name changes
ip_tunnel: Fix name string concatenate in __ip_tunnel_create()
hv_netvsc: Fix a network regression after ifdown/ifup
...
Pull RTC updates from Alexandre Belloni:
"Setting the supported range from drivers for RTCs failing soon has
started. A few fixes are developed along the way. Some drivers have
been switched to SPDX by their maintainers.
Subsystem:
- rework of the rtc-test driver which allows to test the core more
thoroughly
- rtc_set_alarm() now fails early when alarms are not supported
Drivers:
- mktime() is now replaced by mktime64()
- RTC range added for 88pm80x, ab-b5ze-s3, at91rm9200,
brcmstb-waketimer, ds1685, ftrtc010, ls1x, mxc_v2, rx8581, sprd,
st-lpc, tps6586x, tps65910 and vr41xx
- fixed a possible race condition in probe functions
- pxa: fix the probe function that is broken since v4.3
- stm32: now supports stm32mp1"
* tag 'rtc-4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux: (78 commits)
rtc: pxa: fix probe function
rtc: cros-ec: Switch to SPDX identifier.
rtc: cros-ec: Make license text and module license match.
rtc: ensure rtc_set_alarm fails when alarms are not supported
rtc: test: remove alarm support from the first device
rtc: test: convert to devm_rtc_allocate_device
rtc: ftrtc010: let the core handle range
rtc: ftrtc010: handle dates after 2106
rtc: ftrtc010: switch to devm_rtc_allocate_device
rtc: mrst: switch to devm functions
rtc: sunxi: fix possible race condition
rtc: test: remove irq sysfs file
rtc: test: emulate alarms using timers
rtc: test: store time as an offset to system time
rtc: test: allow registering many devices
rtc: test: remove useless proc info
rtc: ds1685: Add range
rtc: ds1685: fix possible race condition
rtc: sprd: Add new RTC power down check method
rtc: sun6i: Fix bit_idx value for clk_register_gate
...
Pull SCSI updates from James Bottomley:
"This is mostly updates to the usual drivers: ufs, qedf, mpt3sas, lpfc,
xfcp, hisi_sas, cxlflash, qla2xxx.
In the absence of Nic, we're also taking target updates which are
mostly minor except for the tcmu refactor.
The only real core change to worry about is the removal of high page
bouncing (in sas, storvsc and iscsi). This has been well tested and no
problems have shown up so far"
* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (268 commits)
scsi: lpfc: update driver version to 12.0.0.4
scsi: lpfc: Fix port initialization failure.
scsi: lpfc: Fix 16gb hbas failing cq create.
scsi: lpfc: Fix crash in blk_mq layer when executing modprobe -r lpfc
scsi: lpfc: correct oversubscription of nvme io requests for an adapter
scsi: lpfc: Fix MDS diagnostics failure (Rx < Tx)
scsi: hisi_sas: Mark PHY as in reset for nexus reset
scsi: hisi_sas: Fix return value when get_free_slot() failed
scsi: hisi_sas: Terminate STP reject quickly for v2 hw
scsi: hisi_sas: Add v2 hw force PHY function for internal ATA command
scsi: hisi_sas: Include TMF elements in struct hisi_sas_slot
scsi: hisi_sas: Try wait commands before before controller reset
scsi: hisi_sas: Init disks after controller reset
scsi: hisi_sas: Create a scsi_host_template per HW module
scsi: hisi_sas: Reset disks when discovered
scsi: hisi_sas: Add LED feature for v3 hw
scsi: hisi_sas: Change common allocation mode of device id
scsi: hisi_sas: change slot index allocation mode
scsi: hisi_sas: Introduce hisi_sas_phy_set_linkrate()
scsi: hisi_sas: fix a typo in hisi_sas_task_prep()
...
Pull restartable sequence support from Thomas Gleixner:
"The restartable sequences syscall (finally):
After a lot of back and forth discussion and massive delays caused by
the speculative distraction of maintainers, the core set of
restartable sequences has finally reached a consensus.
It comes with the basic non disputed core implementation along with
support for arm, powerpc and x86 and a full set of selftests
It was exposed to linux-next earlier this week, so it does not fully
comply with the merge window requirements, but there is really no
point to drag it out for yet another cycle"
* 'core-rseq-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
rseq/selftests: Provide Makefile, scripts, gitignore
rseq/selftests: Provide parametrized tests
rseq/selftests: Provide basic percpu ops test
rseq/selftests: Provide basic test
rseq/selftests: Provide rseq library
selftests/lib.mk: Introduce OVERRIDE_TARGETS
powerpc: Wire up restartable sequences system call
powerpc: Add syscall detection for restartable sequences
powerpc: Add support for restartable sequences
x86: Wire up restartable sequence system call
x86: Add support for restartable sequences
arm: Wire up restartable sequences system call
arm: Add syscall detection for restartable sequences
arm: Add restartable sequences support
rseq: Introduce restartable sequences system call
uapi/headers: Provide types_32_64.h
Pull x86 updates and fixes from Thomas Gleixner:
- Fix the (late) fallout from the vector management rework causing
hlist corruption and irq descriptor reference leaks caused by a
missing sanity check.
The straight forward fix triggered another long standing issue to
surface. The pre rework code hid the issue due to being way slower,
but now the chance that user space sees an EBUSY error return when
updating irq affinities is way higher, though quite a bunch of
userspace tools do not handle it properly despite the fact that EBUSY
could be returned for at least 10 years.
It turned out that the EBUSY return can be avoided completely by
utilizing the existing delayed affinity update mechanism for irq
remapped scenarios as well. That's a bit more error handling in the
kernel, but avoids fruitless fingerpointing discussions with tool
developers.
- Decouple PHYSICAL_MASK from AMD SME as its going to be required for
the upcoming Intel memory encryption support as well.
- Handle legacy device ACPI detection properly for newer platforms
- Fix the wrong argument ordering in the vector allocation tracepoint
- Simplify the IDT setup code for the APIC=n case
- Use the proper string helpers in the MTRR code
- Remove a stale unused VDSO source file
- Convert the microcode update lock to a raw spinlock as its used in
atomic context.
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/intel_rdt: Enable CMT and MBM on new Skylake stepping
x86/apic/vector: Print APIC control bits in debugfs
genirq/affinity: Defer affinity setting if irq chip is busy
x86/platform/uv: Use apic_ack_irq()
x86/ioapic: Use apic_ack_irq()
irq_remapping: Use apic_ack_irq()
x86/apic: Provide apic_ack_irq()
genirq/migration: Avoid out of line call if pending is not set
genirq/generic_pending: Do not lose pending affinity update
x86/apic/vector: Prevent hlist corruption and leaks
x86/vector: Fix the args of vector_alloc tracepoint
x86/idt: Simplify the idt_setup_apic_and_irq_gates()
x86/platform/uv: Remove extra parentheses
x86/mm: Decouple dynamic __PHYSICAL_MASK from AMD SME
x86: Mark native_set_p4d() as __always_inline
x86/microcode: Make the late update update_lock a raw lock for RT
x86/mtrr: Convert to use strncpy_from_user() helper
x86/mtrr: Convert to use match_string() helper
x86/vdso: Remove unused file
x86/i8237: Register device based on FADT legacy boot flag
Pull core fixes from Thomas Gleixner:
"A small set of core updates:
- Make objtool cope with GCC8 oddities some more
- Remove a stale local_irq_save/restore sequence in the signal code
along with the stale comment in the RCU code. The underlying issue
which led to this has been solved long time ago, but nobody cared
to cleanup the hackarounds"
* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
signal: Remove no longer required irqsave/restore
rcu: Update documentation of rcu_read_unlock()
objtool: Fix GCC 8 cold subfunction detection for aliased functions
Pull power supply and reset updates from Sebastian Reichel:
- bq27xxx: Add BQ27426 support
- ab8500: Drop AB8540/9540 support
- Introduced new usb_type property
- Properly document the power-supply ABI
- misc. cleanups and fixes
* tag 'for-v4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/sre/linux-power-supply:
MAINTAINERS: add entry for LEGO MINDSTORMS EV3
power: supply: ab8500_charger: fix spelling mistake: "faile" -> "failed"
power: supply: axp288_fuel_gauge: Remove polling from the driver
power: supply: axp288_fuelguage: Do not bind when the fg function is not used
power: supply: axp288_charger: Do not bind when the charge function is not used
power: supply: axp288_charger: Support 3500 and 4000 mA input current limit
power: supply: s3c-adc-battery: fix driver data initialization
power: supply: charger-manager: Verify polling interval only when polling requested
power: supply: sysfs: Use enum to specify property
power: supply: ab8500: Drop AB8540/9540 support
power: supply: ab8500_fg: fix spelling mistake: "Disharge" -> "Discharge"
power: supply: simplify getting .drvdata
power: supply: bq27xxx: Add support for BQ27426
gpio-poweroff: Use gpiod_set_value_cansleep
Pull clk updates from Stephen Boyd:
"This time we have a good set of changes to the core framework that do
some general cleanups, but nothing too major. The majority of the diff
goes to two SoCs, Actions Semi and Qualcomm. A brand new driver is
introduced for Actions Semi so it takes up some lines to add all the
different types, and the Qualcomm diff is there because we add support
for two SoCs and it's quite a bit of data.
Otherwise the big driver updates are on TI Davinci and Amlogic
platforms. And then the long tail of driver updates for various fixes
and stuff follows after that.
Core:
- debugfs cleanups removing error checking and an unused provider API
- Removal of a clk init typedef that isn't used
- Usage of match_string() to simplify parent string name matching
- OF clk helpers moved to their own file (linux/of_clk.h)
- Make clk warnings more readable across kernel versions
New Drivers:
- Qualcomm SDM845 GCC and Video clk controllers
- Qualcomm MSM8998 GCC
- Actions Semi S900 SoC support
- Nuvoton npcm750 microcontroller clks
- Amlogic axg AO clock controller
Removed Drivers:
- Deprecated Rockchip clk-gate driver
Updates:
- debugfs functions stopped checking return values
- Support for the MSIOF module clocks on Rensas R-Car M3-N
- Support for the new Rensas RZ/G1C and R-Car E3 SoCs
- Qualcomm GDSC, RCG, and PLL updates for clk changes in new SoCs
- Berlin and Amlogic SPDX tagging
- Usage of of_clk_get_parent_count() in more places
- Proper implementation of the CDEV1/2 clocks on Tegra20
- Allwinner H6 PRCM clock support and R40 EMAC support
- Add critical flag to meson8b's fdiv2 as temporary fixup for ethernet
- Round closest support for meson's mpll driver
- Support for meson8b nand clocks and gxbb video decoder clocks
- Mediatek mali clks
- STM32MP1 fixes
- Uniphier LD11/LD20 stream demux system clock"
* tag 'clk-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux: (134 commits)
clk: qcom: Export clk_fabia_pll_configure()
clk: bcm: Update and add Stingray clock entries
dt-bindings: clk: Update Stingray binding doc
clk-si544: Properly round requested frequency to nearest match
clk: ingenic: jz4770: Add 150us delay after enabling VPU clock
clk: ingenic: jz4770: Enable power of AHB1 bus after ungating VPU clock
clk: ingenic: jz4770: Modify C1CLK clock to disable CPU clock stop on idle
clk: ingenic: jz4770: Change OTG from custom to standard gated clock
clk: ingenic: Support specifying "wait for clock stable" delay
clk: ingenic: Add support for clocks whose gate bit is inverted
clk: use match_string() helper
clk: bcm2835: use match_string() helper
clk: Return void from debug_init op
clk: remove clk_debugfs_add_file()
clk: tegra: no need to check return value of debugfs_create functions
clk: davinci: no need to check return value of debugfs_create functions
clk: bcm2835: no need to check return value of debugfs_create functions
clk: no need to check return value of debugfs_create functions
clk: imx6: add EPIT clock support
clk: mvebu: use correct bit for 98DX3236 NAND
...
Pull staging/IIO updates from Greg KH:
"Here is the big staging and IIO driver update for 4.18-rc1.
It was delayed as I wanted to make sure the final driver deletions did
not cause any major merge issues, and all now looks good.
There are a lot of patches here, just over 1000. The diffstat summary
shows the major changes here:
1007 files changed, 16828 insertions(+), 227770 deletions(-)
Because of this, we might be close to shrinking the overall kernel
source code size for two releases in a row.
There was loads of work in this release cycle, primarily:
- tons of ks7010 driver cleanups
- lots of mt7621 driver fixes and cleanups
- most driver cleanups
- wilc1000 fixes and cleanups
- lots and lots of IIO driver cleanups and new additions
- debugfs cleanups for all staging drivers
- lots of other staging driver cleanups and fixes, the shortlog has
the full details.
but the big user-visable things here are the removal of 3 chunks of
code:
- ncpfs and ipx were removed on schedule, no one has cared about this
code since it moved to staging last year, and if it needs to come
back, it can be reverted.
- lustre file system is removed.
I've ranted at the lustre developers about once a year for the past
5 years, with no real forward progress at all to clean things up
and get the code into the "real" part of the kernel.
Given that the lustre developers continue to work on an external
tree and try to port those changes to the in-kernel tree every once
in a while, this whole thing really really is not working out at
all. So I'm deleting it so that the developers can spend the time
working in their out-of-tree location and get things cleaned up
properly to get merged into the tree correctly at a later date.
Because of these file removals, you will have merge issues on some of
these files (2 in the ipx code, 1 in the ncpfs code, and 1 in the
atomisp driver). Just delete those files, it's a simple merge :)
All of this has been in linux-next for a while with no reported
problems"
* tag 'staging-4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (1011 commits)
staging: ipx: delete it from the tree
ncpfs: remove uapi .h files
ncpfs: remove Documentation
ncpfs: remove compat functionality
staging: ncpfs: delete it
staging: lustre: delete the filesystem from the tree.
staging: vc04_services: no need to save the log debufs dentries
staging: vc04_services: vchiq_debugfs_log_entry can be a void *
staging: vc04_services: remove struct vchiq_debugfs_info
staging: vc04_services: move client dbg directory into static variable
staging: vc04_services: remove odd vchiq_debugfs_top() wrapper
staging: vc04_services: no need to check debugfs return values
staging: mt7621-gpio: reorder includes alphabetically
staging: mt7621-gpio: change gc_map to don't use pointers
staging: mt7621-gpio: use GPIOF_DIR_OUT and GPIOF_DIR_IN macros instead of custom values
staging: mt7621-gpio: change 'to_mediatek_gpio' to make just a one line return
staging: mt7621-gpio: dt-bindings: update documentation for #interrupt-cells property
staging: mt7621-gpio: update #interrupt-cells for the gpio node
staging: mt7621-gpio: dt-bindings: complete documentation for the gpio
staging: mt7621-dts: add missing properties to gpio node
...
Pull libnvdimm updates from Dan Williams:
"This adds a user for the new 'bytes-remaining' updates to
memcpy_mcsafe() that you already received through Ingo via the
x86-dax- for-linus pull.
Not included here, but still targeting this cycle, is support for
handling memory media errors (poison) consumed via userspace dax
mappings.
Summary:
- DAX broke a fundamental assumption of truncate of file mapped
pages. The truncate path assumed that it is safe to disconnect a
pinned page from a file and let the filesystem reclaim the physical
block. With DAX the page is equivalent to the filesystem block.
Introduce dax_layout_busy_page() to enable filesystems to wait for
pinned DAX pages to be released. Without this wait a filesystem
could allocate blocks under active device-DMA to a new file.
- DAX arranges for the block layer to be bypassed and uses
dax_direct_access() + copy_to_iter() to satisfy read(2) calls.
However, the memcpy_mcsafe() facility is available through the pmem
block driver. In order to safely handle media errors, via the DAX
block-layer bypass, introduce copy_to_iter_mcsafe().
- Fix cache management policy relative to the ACPI NFIT Platform
Capabilities Structure to properly elide cache flushes when they
are not necessary. The table indicates whether CPU caches are
power-fail protected. Clarify that a deep flush is always performed
on REQ_{FUA,PREFLUSH} requests"
* tag 'libnvdimm-for-4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (21 commits)
dax: Use dax_write_cache* helpers
libnvdimm, pmem: Do not flush power-fail protected CPU caches
libnvdimm, pmem: Unconditionally deep flush on *sync
libnvdimm, pmem: Complete REQ_FLUSH => REQ_PREFLUSH
acpi, nfit: Remove ecc_unit_size
dax: dax_insert_mapping_entry always succeeds
libnvdimm, e820: Register all pmem resources
libnvdimm: Debug probe times
linvdimm, pmem: Preserve read-only setting for pmem devices
x86, nfit_test: Add unit test for memcpy_mcsafe()
pmem: Switch to copy_to_iter_mcsafe()
dax: Report bytes remaining in dax_iomap_actor()
dax: Introduce a ->copy_to_iter dax operation
uio, lib: Fix CONFIG_ARCH_HAS_UACCESS_MCSAFE compilation
xfs, dax: introduce xfs_break_dax_layouts()
xfs: prepare xfs_break_layouts() for another layout type
xfs: prepare xfs_break_layouts() to be called with XFS_MMAPLOCK_EXCL
mm, fs, dax: handle layout changes to pinned dax mappings
mm: fix __gup_device_huge vs unmap
mm: introduce MEMORY_DEVICE_FS_DAX and CONFIG_DEV_PAGEMAP_OPS
...
After commit 6b229cf77d ("udp: add batching to udp_rmem_release()")
the sk_rmem_alloc field does not measure exactly anymore the
receive queue length, because we batch the rmem release. The issue
is really apparent only after commit 0d4a6608f6 ("udp: do rmem bulk
free even if the rx sk queue is empty"): the user space can easily
check for an empty socket with not-0 queue length reported by the 'ss'
tool or the procfs interface.
We need to use a custom UDP helper to report the correct queue length,
taking into account the forward allocation deficit.
Reported-by: trevor.francis@46labs.com
Fixes: 6b229cf77d ("UDP: add batching to udp_rmem_release()")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull block fixes from Jens Axboe:
"A few fixes for this merge window, where some of them should go in
sooner rather than later, hence a new pull this week. This pull
request contains:
- Set of NVMe fixes, mostly follow up cleanups/fixes to the queue
changes, but also teardown/removal and misc changes (Christop/Dan/
Johannes/Sagi/Steve).
- Two lightnvm fixes for issues that showed up in this window
(Colin/Wei).
- Failfast/driver flags inheritance for flush requests (Hannes).
- The md device put sanitization and fix (Kent).
- dm bio_set inheritance fix (me).
- nbd discard granularity fix (Josef).
- nbd consistency in command printing (Kevin).
- Loop recursion validation fix (Ted).
- Partition overlap check (Wang)"
[ .. and now my build is warning-free again thanks to the md fix - Linus ]
* tag 'for-linus-20180608' of git://git.kernel.dk/linux-block: (22 commits)
nvme: cleanup double shift issue
nvme-pci: make CMB SQ mod-param read-only
nvme-pci: unquiesce dead controller queues
nvme-pci: remove HMB teardown on reset
nvme-pci: queue creation fixes
nvme-pci: remove unnecessary completion doorbell check
nvme-pci: remove unnecessary nested locking
nvmet: filter newlines from user input
nvme-rdma: correctly check for target keyed sgl support
nvme: don't hold nvmf_transports_rwsem for more than transport lookups
nvmet: return all zeroed buffer when we can't find an active namespace
md: Unify mddev destruction paths
dm: use bioset_init_from_src() to copy bio_set
block: add bioset_init_from_src() helper
block: always set partition number to '0' in blk_partition_remap()
block: pass failfast and driver-specific flags to flush requests
nbd: set discard_alignment to the granularity
nbd: Consistently use request pointer in debug messages.
block: add verifier for cmdline partition
lightnvm: pblk: fix resource leak of invalid_bitmap
...
Pull regulator updates from Mark Brown:
"Quite a lot of core work this time around, though not 100% successful.
We gained support for runtime mode changes thanks to David Collins and
improved support for write only regulators (ones where we can't read
back the configuration) from Douglas Anderson.
There's been quite a bit of work from Linus Walleij on converting from
specfying GPIOs by numbers to descriptors. Sadly the testing turned
out to be less good than we had hoped and so a lot of this had to be
reverted.
We also have the start of updates to use coupled regulators from
Maciej Purski, unfortunately there are further problems there so the
last couple of patches have been reverted.
We also have new drivers for BD71837 and SY8106A devices, SAW
regulators on Qualcomm SPMI and dropped support for some preproduction
chips that never made it to market from the AB8500 driver"
* tag 'regulator-v4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator: (57 commits)
regulator: gpio: Revert
ARM: pxa, regulator: fix building ezx e680
regulator: Revert coupled regulator support again
regulator: wm8994: Fix shared GPIOs
regulator: max77686: Fix shared GPIOs
regulator: bd71837: BD71837 PMIC regulator driver
regulator: bd71837: Devicetree bindings for BD71837 regulators
regulator: gpio: Get enable GPIO using GPIO descriptor
regulator: fixed: Convert to use GPIO descriptor only
regulator: s2mps11: Fix boot on Odroid XU3
dt-bindings: qcom_spmi: Document SAW support
regulator: qcom_spmi: Add support for SAW
regulator: tps65090: Pass descriptor instead of GPIO number
regulator: s5m8767: Pass descriptor instead of GPIO number
regulator: pfuze100: Delete reference to ena_gpio
regulator: max8952: Pass descriptor instead of GPIO number
regulator: lp8788-ldo: Pass descriptor instead of GPIO number
regulator: lm363x: Pass descriptor instead of GPIO number
regulator: max8973: Pass descriptor instead of GPIO number
regulator: mc13xxx-core: Switch to SPDX identifier
...
Pull arm64 updates from Catalin Marinas:
"Apart from the core arm64 and perf changes, the Spectre v4 mitigation
touches the arm KVM code and the ACPI PPTT support touches drivers/
(acpi and cacheinfo). I should have the maintainers' acks in place.
Summary:
- Spectre v4 mitigation (Speculative Store Bypass Disable) support
for arm64 using SMC firmware call to set a hardware chicken bit
- ACPI PPTT (Processor Properties Topology Table) parsing support and
enable the feature for arm64
- Report signal frame size to user via auxv (AT_MINSIGSTKSZ). The
primary motivation is Scalable Vector Extensions which requires
more space on the signal frame than the currently defined
MINSIGSTKSZ
- ARM perf patches: allow building arm-cci as module, demote
dev_warn() to dev_dbg() in arm-ccn event_init(), miscellaneous
cleanups
- cmpwait() WFE optimisation to avoid some spurious wakeups
- L1_CACHE_BYTES reverted back to 64 (for performance reasons that
have to do with some network allocations) while keeping
ARCH_DMA_MINALIGN to 128. cache_line_size() returns the actual
hardware Cache Writeback Granule
- Turn LSE atomics on by default in Kconfig
- Kernel fault reporting tidying
- Some #include and miscellaneous cleanups"
* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (53 commits)
arm64: Fix syscall restarting around signal suppressed by tracer
arm64: topology: Avoid checking numa mask for scheduler MC selection
ACPI / PPTT: fix build when CONFIG_ACPI_PPTT is not enabled
arm64: cpu_errata: include required headers
arm64: KVM: Move VCPU_WORKAROUND_2_FLAG macros to the top of the file
arm64: signal: Report signal frame size to userspace via auxv
arm64/sve: Thin out initialisation sanity-checks for sve_max_vl
arm64: KVM: Add ARCH_WORKAROUND_2 discovery through ARCH_FEATURES_FUNC_ID
arm64: KVM: Handle guest's ARCH_WORKAROUND_2 requests
arm64: KVM: Add ARCH_WORKAROUND_2 support for guests
arm64: KVM: Add HYP per-cpu accessors
arm64: ssbd: Add prctl interface for per-thread mitigation
arm64: ssbd: Introduce thread flag to control userspace mitigation
arm64: ssbd: Restore mitigation status on CPU resume
arm64: ssbd: Skip apply_ssbd if not using dynamic mitigation
arm64: ssbd: Add global mitigation state accessor
arm64: Add 'ssbd' command-line option
arm64: Add ARCH_WORKAROUND_2 probing
arm64: Add per-cpu infrastructure to call ARCH_WORKAROUND_2
arm64: Call ARCH_WORKAROUND_2 on transitions between EL0 and EL1
...
Pull dmaengine updates from Vinod Koul:
- updates to sprd, bam_dma, stm drivers
- remove VLAs in dmatest
- move TI drivers to their own subdir
- switch to SPDX tags for ima/mxs dma drivers
- simplify getting .drvdata on bunch of drivers by Wolfram Sang
* tag 'dmaengine-4.18-rc1' of git://git.infradead.org/users/vkoul/slave-dma: (32 commits)
dmaengine: sprd: Add Spreadtrum DMA configuration
dmaengine: sprd: Optimize the sprd_dma_prep_dma_memcpy()
dmaengine: imx-dma: Switch to SPDX identifier
dmaengine: mxs-dma: Switch to SPDX identifier
dmaengine: imx-sdma: Switch to SPDX identifier
dmaengine: usb-dmac: Document R8A7799{0,5} bindings
dmaengine: qcom: bam_dma: fix some doc warnings.
dmaengine: qcom: bam_dma: fix invalid assignment warning
dmaengine: sprd: fix an NULL vs IS_ERR() bug
dmaengine: sprd: Use devm_ioremap_resource() to map memory
dmaengine: sprd: Fix potential NULL dereference in sprd_dma_probe()
dmaengine: pl330: flush before wait, and add dev burst support.
dmaengine: axi-dmac: Request IRQ with IRQF_SHARED
dmaengine: stm32-mdma: fix spelling mistake: "avalaible" -> "available"
dmaengine: rcar-dmac: Document R-Car D3 bindings
dmaengine: sprd: Move DMA request mode and interrupt type into head file
dmaengine: sprd: Define the DMA data width type
dmaengine: sprd: Define the DMA transfer step type
dmaengine: ti: New directory for Texas Instruments DMA drivers
dmaengine: shdmac: Change platform check to CONFIG_ARCH_RENESAS
...
Pull IOMMU updates from Joerg Roedel:
"Nothing big this time. In particular:
- Debugging code for Tegra-GART
- Improvement in Intel VT-d fault printing to prevent soft-lockups
when on fault storms
- Improvements in AMD IOMMU event reporting
- NUMA aware allocation in io-pgtable code for ARM
- Various other small fixes and cleanups all over the place"
* tag 'iommu-updates-v4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
iommu/io-pgtable-arm: Make allocations NUMA-aware
iommu/amd: Prevent possible null pointer dereference and infinite loop
iommu/amd: Fix grammar of comments
iommu: Clean up the comments for iommu_group_alloc
iommu/vt-d: Remove unnecessary parentheses
iommu/vt-d: Clean up pasid quirk for pre-production devices
iommu/vt-d: Clean up unused variable in find_or_alloc_domain
iommu/vt-d: Fix iotlb psi missing for mappings
iommu/vt-d: Introduce __mapping_notify_one()
iommu: Remove extra NULL check when call strtobool()
iommu/amd: Update logging information for new event type
iommu/amd: Update the PASID information printed to the system log
iommu/tegra: gart: Fix gart_iommu_unmap()
iommu/tegra: gart: Add debugging facility
iommu/io-pgtable-arm: Use for_each_set_bit to simplify code
iommu/qcom: Simplify getting .drvdata
iommu: Remove depends on HAS_DMA in case of platform dependency
iommu/vt-d: Ratelimit each dmar fault printing
Pull MTD updates from Boris Brezillon:
"Core changes:
- Add a sysfs attribute to expose available OOB size
Driver changes:
- Remove HAS_DMA dependency on various drivers
- Use dev_get_drvdata() instead of platform_get_drvdata() in docg3
- Replace msleep by usleep_range() in the dataflash driver
- Avoid VLA usage in nftl layers
- Remove useless .owner assignment in pismo
- Fix various issues in the CFI driver
- Improve TRX partition handling expose a DT compat for this part
parser
- Clarify OFFSET_CONTINUOUS meaning
NAND core changes:
- Add Miquel as a NAND maintainer
- Add access mode to the nand_page_io_req struct
- Fix kernel-doc in rawnand.h
- Support bit-wise majority to recover from corrupted ONFI parameter
pages
- Stop checking FAIL bit after a SET_FEATURES, as documented in the
ONFI spec
Raw NAND Driver changes:
- Fix and cleanup the error path of many NAND controller drivers
- GPMI:
+ Cleanup/simplification of a few aspects in the driver
+ Take ECC setup specified in the DT into account
- sunxi: remove support for GPIO-based R/B polling
- MTK:
+ Use of_device_get_match_data() instead of of_match_device()
+ Add an entry in MAINTAINERS for this driver
+ Fix nand-ecc-step-size and nand-ecc-strength description in the
DT bindings doc
- fsl_ifc: fix ->cmdfunc() to read more than one ONFI parameter page
OneNAND driver changes:
- samsung: use dev_get_drvdata() instead of platform_get_drvdata()
SPI NOR core changes:
- Add support for a bunch of SPI NOR chips
- Clear EAR reg when switching to 3-byte addressing mode on Winbond
chips
SPI NOR controller driver changes:
- cadence: Add DMA support for direct mode reads
- hisi: Prefix a few functions with hisi_
- intel:
+ Mark the driver as "dangerous" in Kconfig
+ Fix atomic sequence handling
+ Pass a 40us delay (instead of 0us) to readl_poll_timeout()
- fsl:
+ fix a typo in a function name
+ add support for IP variants embedded in the ls2080a and ls1080a
SoCs
- stm32: request exclusive control of the reset line"
* tag 'mtd/for-4.18' of git://git.infradead.org/linux-mtd: (66 commits)
mtd: nand: Pass mode information to nand_page_io_req
mtd: cfi_cmdset_0002: Change erase one block to enable XIP once
mtd: cfi_cmdset_0002: Change erase functions to check chip good only
mtd: cfi_cmdset_0002: Change erase functions to retry for error
mtd: cfi_cmdset_0002: Change definition naming to retry write operation
mtd: cfi_cmdset_0002: Change write buffer to check correct value
mtd: cmdlinepart: Update comment for introduction of OFFSET_CONTINUOUS
mtd: bcm47xxpart: add of_match_table with a new DT binding
dt-bindings: mtd: document Broadcom's BCM47xx partitions
mtd: spi-nor: Add support for EN25QH32
mtd: spi-nor: Add support for is25wp series chips
mtd: spi-nor: Add Winbond w25q32jv support
mtd: spi-nor: fsl-quadspi: add support for ls2080a/ls1080a
mtd: spi-nor: stm32-quadspi: explicitly request exclusive reset control
mtd: spi-nor: intel: provide a range for poll_timout
mtd: spi-nor: fsl-quadspi: fix api naming typo _init_ahb_read
mtd: spi-nor: intel-spi: Explicitly mark the driver as dangerous in Kconfig
mtd: spi-nor: intel-spi: Fix atomic sequence handling
mtd: rawnand: Do not check FAIL bit when executing a SET_FEATURES op
mtd: rawnand: use bit-wise majority to recover the ONFI param page
...
Pull GPIO updates from Linus Walleij:
"This is the bulk of GPIO changes for the v4.18 development cycle.
Core changes:
- We have killed off VLA from the core library and all drivers.
The background should be clear for everyone at this point:
https://lwn.net/Articles/749064/
Also I just don't like VLA's, kernel developers hate it when
compilers do things behind their back. It's as simple as that.
I'm sorry that they even slipped in to begin with. Kudos to Laura
Abbott for exorcising them.
- Support GPIO hogs in machines/board files.
New drivers and chip support:
- R-Car r8a77470 (RZ/G1C)
- R-Car r8a77965 (M3-N)
- R-Car r8a77990 (E3)
- PCA953x driver improvements to accomodate more variants.
Improvements and new features:
- Support one interrupt per line on port A in the DesignWare dwapb
driver.
Misc:
- Random cleanups, right header files in the drivers, some size
optimizations etc"
* tag 'gpio-v4.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (73 commits)
gpio: davinci: fix build warning when !CONFIG_OF
gpio: dwapb: Fix rework support for 1 interrupt per port A GPIO
gpio: pxa: Include the right header
gpio: pl061: Include the right header
gpio: pch: Include the right header
gpio: pcf857x: Include the right header
gpio: pca953x: Include the right header
gpio: palmas: Include the right header
gpio: omap: Include the right header
gpio: octeon: Include the right header
gpio: mxs: Switch to SPDX identifier
gpio: Remove VLA from stmpe driver
gpio: mxc: Switch to SPDX identifier
gpio: mxc: add clock operation
gpio: Remove VLA from gpiolib
gpio: aspeed: Use a cache of output data registers
gpio: aspeed: Set output latch before changing direction
gpio: pca953x: fix address calculation for pcal6524
gpio: pca953x: define masks for addressing common and extended registers
gpio: pca953x: set the PCA_PCAL flag also when matching by DT
...
Pull HID updates from Jiri Kosina:
- Valve Steam Controller support from Rodrigo Rivas Costa
- Redragon Asura support from Robert Munteanu
- improvement of duplicate usage handling in generic hid-input from
Benjamin Tissoires
- Win 8.1 precisioun touchpad spec implementation from Benjamin
Tissoires
- Support for "In Range" flag for Wacom Intuos/Bamboo devices from
Jason Gerecke
- other various assorted smaller fixes and improvements
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid: (27 commits)
HID: rmi: use HID_QUIRK_NO_INPUT_SYNC
HID: multitouch: fix calculation of last slot field in multi-touch reports
HID: quirks: remove Delcom Visual Signal Indicator from hid_have_special_driver[]
HID: steam: select CONFIG_POWER_SUPPLY
HID: i2c-hid: remove i2c_hid_open_mut
HID: wacom: Support "in range" for Intuos/Bamboo tablets where possible
HID: core: fix hid_hw_open() comment
HID: hid-plantronics: Re-resend Update to map button for PTT products
HID: multitouch: fix types returned from mt_need_to_apply_feature()
HID: i2c-hid: check if device is there before really probing
HID: steam: add missing fields in client initialization
HID: steam: add battery device.
HID: add driver for Valve Steam Controller
HID: alps: Fix some style in 't4_read_write_register()'
HID: alps: Check errors returned by 't4_read_write_register()'
HID: alps: Save a memory allocation in 't4_read_write_register()' when writing data
HID: alps: Report an error if we receive invalid data in 't4_read_write_register()'
HID: multitouch: implement precision touchpad latency and switches
HID: multitouch: simplify the settings of the various features
HID: multitouch: make use of HID_QUIRK_INPUT_PER_APP
...
Pull aio iopriority support from Al Viro:
"The rest of aio stuff for this cycle - Adam's aio ioprio series"
* 'work.aio' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
fs: aio ioprio use ioprio_check_cap ret val
fs: aio ioprio add explicit block layer dependence
fs: iomap dio set bio prio from kiocb prio
fs: blkdev set bio prio from kiocb prio
fs: Add aio iopriority support
fs: Convert kiocb rw_hint from enum to u16
block: add ioprio_check_cap function
Pull xen updates from Juergen Gross:
"This contains some minor code cleanups (fixing return types of
functions), some fixes for Linux running as Xen PVH guest, and adding
of a new guest resource mapping feature for Xen tools"
* tag 'for-linus-4.18-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
xen/PVH: Make GDT selectors PVH-specific
xen/PVH: Set up GS segment for stack canary
xen/store: do not store local values in xen_start_info
xen-netfront: fix xennet_start_xmit()'s return type
xen/privcmd: add IOCTL_PRIVCMD_MMAP_RESOURCE
xen: Change return type to vm_fault_t
include/net/netfilter/nft_dup.h was introduced in d877f07112 ("netfilter: nf_tables: add nft_dup expression")
but was never user since this date.
Furthermore, the only struct in this file is unused elsewhere.
Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
- improvement of duplicate usage handling in hid-input from Benjamin Tissoires
- Win 8.1 precisioun touchpad spec implementation from Benjamin Tissoires
Merge updates from Andrew Morton:
- a few misc things
- ocfs2 updates
- v9fs updates
- MM
- procfs updates
- lib/ updates
- autofs updates
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (118 commits)
autofs: small cleanup in autofs_getpath()
autofs: clean up includes
autofs: comment on selinux changes needed for module autoload
autofs: update MAINTAINERS entry for autofs
autofs: use autofs instead of autofs4 in documentation
autofs: rename autofs documentation files
autofs: create autofs Kconfig and Makefile
autofs: delete fs/autofs4 source files
autofs: update fs/autofs4/Makefile
autofs: update fs/autofs4/Kconfig
autofs: copy autofs4 to autofs
autofs4: use autofs instead of autofs4 everywhere
autofs4: merge auto_fs.h and auto_fs4.h
fs/binfmt_misc.c: do not allow offset overflow
checkpatch: improve patch recognition
lib/ucs2_string.c: add MODULE_LICENSE()
lib/mpi: headers cleanup
lib/percpu_ida.c: use _irqsave() instead of local_irq_save() + spin_lock
lib/idr.c: remove simple_ida_lock
lib/bitmap.c: micro-optimization for __bitmap_complement()
...
The LKP robot found a 27% will-it-scale/page_fault3 performance
regression regarding commit e27be240df53("mm: memcg: make sure
memory.events is uptodate when waking pollers").
What the test does is:
1 mkstemp() a 128M file on a tmpfs;
2 start $nr_cpu processes, each to loop the following:
2.1 mmap() this file in shared write mode;
2.2 write 0 to this file in a PAGE_SIZE step till the end of the file;
2.3 unmap() this file and repeat this process.
3 After 5 minutes, check how many loops they managed to complete, the
higher the better.
The commit itself looks innocent enough as it merely changed some event
counting mechanism and this test didn't trigger those events at all.
Perf shows increased cycles spent on accessing root_mem_cgroup->stat_cpu
in count_memcg_event_mm()(called by handle_mm_fault()) and in
__mod_memcg_state() called by page_add_file_rmap(). So it's likely due
to the changed layout of 'struct mem_cgroup' that either make stat_cpu
falling into a constantly modifying cacheline or some hot fields stop
being in the same cacheline.
I verified this by moving memory_events[] back to where it was:
: --- a/include/linux/memcontrol.h
: +++ b/include/linux/memcontrol.h
: @@ -205,7 +205,6 @@ struct mem_cgroup {
: int oom_kill_disable;
:
: /* memory.events */
: - atomic_long_t memory_events[MEMCG_NR_MEMORY_EVENTS];
: struct cgroup_file events_file;
:
: /* protect arrays of thresholds */
: @@ -238,6 +237,7 @@ struct mem_cgroup {
: struct mem_cgroup_stat_cpu __percpu *stat_cpu;
: atomic_long_t stat[MEMCG_NR_STAT];
: atomic_long_t events[NR_VM_EVENT_ITEMS];
: + atomic_long_t memory_events[MEMCG_NR_MEMORY_EVENTS];
:
: unsigned long socket_pressure;
And performance restored.
Later investigation found that as long as the following 3 fields
moving_account, move_lock_task and stat_cpu are in the same cacheline,
performance will be good. To avoid future performance surprise by other
commits changing the layout of 'struct mem_cgroup', this patch makes
sure the 3 fields stay in the same cacheline.
One concern of this approach is, moving_account and move_lock_task could
be modified when a process changes memory cgroup while stat_cpu is a
always read field, it might hurt to place them in the same cacheline. I
assume it is rare for a process to change memory cgroup so this should
be OK.
Link: https://lkml.kernel.org/r/20180528114019.GF9904@yexl-desktop
Link: http://lkml.kernel.org/r/20180601071115.GA27302@intel.com
Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Reported-by: kernel test robot <xiaolong.ye@intel.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If a process monitored with userfaultfd changes it's memory mappings or
forks() at the same time as uffd monitor fills the process memory with
UFFDIO_COPY, the actual creation of page table entries and copying of
the data in mcopy_atomic may happen either before of after the memory
mapping modifications and there is no way for the uffd monitor to
maintain consistent view of the process memory layout.
For instance, let's consider fork() running in parallel with
userfaultfd_copy():
process | uffd monitor
---------------------------------+------------------------------
fork() | userfaultfd_copy()
... | ...
dup_mmap() | down_read(mmap_sem)
down_write(mmap_sem) | /* create PTEs, copy data */
dup_uffd() | up_read(mmap_sem)
copy_page_range() |
up_write(mmap_sem) |
dup_uffd_complete() |
/* notify monitor */ |
If the userfaultfd_copy() takes the mmap_sem first, the new page(s) will
be present by the time copy_page_range() is called and they will appear
in the child's memory mappings. However, if the fork() is the first to
take the mmap_sem, the new pages won't be mapped in the child's address
space.
If the pages are not present and child tries to access them, the monitor
will get page fault notification and everything is fine. However, if
the pages *are present*, the child can access them without uffd
noticing. And if we copy them into child it'll see the wrong data.
Since we are talking about background copy, we'd need to decide whether
the pages should be copied or not regardless #PF notifications.
Since userfaultfd monitor has no way to determine what was the order,
let's disallow userfaultfd_copy in parallel with the non-cooperative
events. In such case we return -EAGAIN and the uffd monitor can
understand that userfaultfd_copy() clashed with a non-cooperative event
and take an appropriate action.
Link: http://lkml.kernel.org/r/1527061324-19949-1-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Acked-by: Pavel Emelyanov <xemul@virtuozzo.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Andrei Vagin <avagin@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
