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Merge 4.9.188 into android-4.9-q
Changes in 4.9.188
ARM: riscpc: fix DMA
ARM: dts: rockchip: Make rk3288-veyron-minnie run at hs200
ARM: dts: rockchip: Make rk3288-veyron-mickey's emmc work again
ARM: dts: rockchip: Mark that the rk3288 timer might stop in suspend
ftrace: Enable trampoline when rec count returns back to one
kernel/module.c: Only return -EEXIST for modules that have finished loading
MIPS: lantiq: Fix bitfield masking
dmaengine: rcar-dmac: Reject zero-length slave DMA requests
fs/adfs: super: fix use-after-free bug
btrfs: fix minimum number of chunk errors for DUP
ceph: fix improper use of smp_mb__before_atomic()
ceph: return -ERANGE if virtual xattr value didn't fit in buffer
scsi: zfcp: fix GCC compiler warning emitted with -Wmaybe-uninitialized
ACPI: fix false-positive -Wuninitialized warning
be2net: Signal that the device cannot transmit during reconfiguration
x86/apic: Silence -Wtype-limits compiler warnings
x86: math-emu: Hide clang warnings for 16-bit overflow
mm/cma.c: fail if fixed declaration can't be honored
coda: add error handling for fget
coda: fix build using bare-metal toolchain
uapi linux/coda_psdev.h: move upc_req definition from uapi to kernel side headers
drivers/rapidio/devices/rio_mport_cdev.c: NUL terminate some strings
ipc/mqueue.c: only perform resource calculation if user valid
x86/kvm: Don't call kvm_spurious_fault() from .fixup
x86, boot: Remove multiple copy of static function sanitize_boot_params()
kbuild: initialize CLANG_FLAGS correctly in the top Makefile
Btrfs: fix incremental send failure after deduplication
mmc: dw_mmc: Fix occasional hang after tuning on eMMC
gpiolib: fix incorrect IRQ requesting of an active-low lineevent
selinux: fix memory leak in policydb_init()
s390/dasd: fix endless loop after read unit address configuration
drivers/perf: arm_pmu: Fix failure path in PM notifier
xen/swiotlb: fix condition for calling xen_destroy_contiguous_region()
IB/mlx5: Fix RSS Toeplitz setup to be aligned with the HW specification
coredump: fix race condition between mmget_not_zero()/get_task_mm() and core dumping
infiniband: fix race condition between infiniband mlx4, mlx5 driver and core dumping
coredump: fix race condition between collapse_huge_page() and core dumping
eeprom: at24: make spd world-readable again
Backport minimal compiler_attributes.h to support GCC 9
include/linux/module.h: copy __init/__exit attrs to init/cleanup_module
objtool: Support GCC 9 cold subfunction naming scheme
x86, mm, gup: prevent get_page() race with munmap in paravirt guest
Linux 4.9.188
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
This adds support for __copy to v4.9.y so that we can use it in
init/exit_module to avoid -Werror=missing-attributes errors on GCC 9.
Link: https://lore.kernel.org/lkml/259986242.BvXPX32bHu@devpool35/
Cc: <stable@vger.kernel.org>
Suggested-by: Rolf Eike Beer <eb@emlix.com>
Signed-off-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge 4.9.187 into android-4.9-q
Changes in 4.9.187
MIPS: ath79: fix ar933x uart parity mode
MIPS: fix build on non-linux hosts
arm64/efi: Mark __efistub_stext_offset as an absolute symbol explicitly
dmaengine: imx-sdma: fix use-after-free on probe error path
ath10k: Do not send probe response template for mesh
ath9k: Check for errors when reading SREV register
ath6kl: add some bounds checking
ath: DFS JP domain W56 fixed pulse type 3 RADAR detection
batman-adv: fix for leaked TVLV handler.
media: dvb: usb: fix use after free in dvb_usb_device_exit
crypto: talitos - fix skcipher failure due to wrong output IV
media: marvell-ccic: fix DMA s/g desc number calculation
media: vpss: fix a potential NULL pointer dereference
media: media_device_enum_links32: clean a reserved field
net: stmmac: dwmac1000: Clear unused address entries
net: stmmac: dwmac4/5: Clear unused address entries
signal/pid_namespace: Fix reboot_pid_ns to use send_sig not force_sig
af_key: fix leaks in key_pol_get_resp and dump_sp.
xfrm: Fix xfrm sel prefix length validation
media: mc-device.c: don't memset __user pointer contents
media: staging: media: davinci_vpfe: - Fix for memory leak if decoder initialization fails.
net: phy: Check against net_device being NULL
crypto: talitos - properly handle split ICV.
crypto: talitos - Align SEC1 accesses to 32 bits boundaries.
tua6100: Avoid build warnings.
locking/lockdep: Fix merging of hlocks with non-zero references
media: wl128x: Fix some error handling in fm_v4l2_init_video_device()
cpupower : frequency-set -r option misses the last cpu in related cpu list
net: fec: Do not use netdev messages too early
net: axienet: Fix race condition causing TX hang
s390/qdio: handle PENDING state for QEBSM devices
perf cs-etm: Properly set the value of 'old' and 'head' in snapshot mode
perf test 6: Fix missing kvm module load for s390
gpio: omap: fix lack of irqstatus_raw0 for OMAP4
gpio: omap: ensure irq is enabled before wakeup
regmap: fix bulk writes on paged registers
bpf: silence warning messages in core
rcu: Force inlining of rcu_read_lock()
blkcg, writeback: dead memcgs shouldn't contribute to writeback ownership arbitration
xfrm: fix sa selector validation
perf evsel: Make perf_evsel__name() accept a NULL argument
vhost_net: disable zerocopy by default
ipoib: correcly show a VF hardware address
EDAC/sysfs: Fix memory leak when creating a csrow object
ipsec: select crypto ciphers for xfrm_algo
media: i2c: fix warning same module names
ntp: Limit TAI-UTC offset
timer_list: Guard procfs specific code
acpi/arm64: ignore 5.1 FADTs that are reported as 5.0
media: coda: fix mpeg2 sequence number handling
media: coda: increment sequence offset for the last returned frame
mt7601u: do not schedule rx_tasklet when the device has been disconnected
x86/build: Add 'set -e' to mkcapflags.sh to delete broken capflags.c
mt7601u: fix possible memory leak when the device is disconnected
ath10k: fix PCIE device wake up failed
perf tools: Increase MAX_NR_CPUS and MAX_CACHES
libata: don't request sense data on !ZAC ATA devices
clocksource/drivers/exynos_mct: Increase priority over ARM arch timer
rslib: Fix decoding of shortened codes
rslib: Fix handling of of caller provided syndrome
ixgbe: Check DDM existence in transceiver before access
crypto: asymmetric_keys - select CRYPTO_HASH where needed
EDAC: Fix global-out-of-bounds write when setting edac_mc_poll_msec
bcache: check c->gc_thread by IS_ERR_OR_NULL in cache_set_flush()
iwlwifi: mvm: Drop large non sta frames
net: usb: asix: init MAC address buffers
gpiolib: Fix references to gpiod_[gs]et_*value_cansleep() variants
Bluetooth: hci_bcsp: Fix memory leak in rx_skb
Bluetooth: 6lowpan: search for destination address in all peers
Bluetooth: Check state in l2cap_disconnect_rsp
Bluetooth: validate BLE connection interval updates
gtp: fix Illegal context switch in RCU read-side critical section.
gtp: fix use-after-free in gtp_newlink()
xen: let alloc_xenballooned_pages() fail if not enough memory free
scsi: NCR5380: Reduce goto statements in NCR5380_select()
scsi: NCR5380: Always re-enable reselection interrupt
scsi: mac_scsi: Increase PIO/PDMA transfer length threshold
crypto: ghash - fix unaligned memory access in ghash_setkey()
crypto: arm64/sha1-ce - correct digest for empty data in finup
crypto: arm64/sha2-ce - correct digest for empty data in finup
crypto: chacha20poly1305 - fix atomic sleep when using async algorithm
crypto: crypto4xx - fix a potential double free in ppc4xx_trng_probe
Input: gtco - bounds check collection indent level
regulator: s2mps11: Fix buck7 and buck8 wrong voltages
arm64: tegra: Update Jetson TX1 GPU regulator timings
iwlwifi: pcie: don't service an interrupt that was masked
tracing/snapshot: Resize spare buffer if size changed
NFSv4: Handle the special Linux file open access mode
lib/scatterlist: Fix mapping iterator when sg->offset is greater than PAGE_SIZE
ALSA: seq: Break too long mutex context in the write loop
ALSA: hda/realtek: apply ALC891 headset fixup to one Dell machine
media: v4l2: Test type instead of cfg->type in v4l2_ctrl_new_custom()
media: coda: Remove unbalanced and unneeded mutex unlock
KVM: x86/vPMU: refine kvm_pmu err msg when event creation failed
arm64: tegra: Fix AGIC register range
fs/proc/proc_sysctl.c: fix the default values of i_uid/i_gid on /proc/sys inodes.
drm/nouveau/i2c: Enable i2c pads & busses during preinit
padata: use smp_mb in padata_reorder to avoid orphaned padata jobs
9p/virtio: Add cleanup path in p9_virtio_init
PCI: Do not poll for PME if the device is in D3cold
Btrfs: add missing inode version, ctime and mtime updates when punching hole
libnvdimm/pfn: fix fsdax-mode namespace info-block zero-fields
take floppy compat ioctls to sodding floppy.c
floppy: fix div-by-zero in setup_format_params
floppy: fix out-of-bounds read in next_valid_format
floppy: fix invalid pointer dereference in drive_name
floppy: fix out-of-bounds read in copy_buffer
coda: pass the host file in vma->vm_file on mmap
gpu: ipu-v3: ipu-ic: Fix saturation bit offset in TPMEM
crypto: ccp - Validate the the error value used to index error messages
PCI: hv: Delete the device earlier from hbus->children for hot-remove
PCI: hv: Fix a use-after-free bug in hv_eject_device_work()
crypto: caam - limit output IV to CBC to work around CTR mode DMA issue
um: Allow building and running on older hosts
um: Fix FP register size for XSTATE/XSAVE
parisc: Ensure userspace privilege for ptraced processes in regset functions
parisc: Fix kernel panic due invalid values in IAOQ0 or IAOQ1
powerpc/32s: fix suspend/resume when IBATs 4-7 are used
powerpc/watchpoint: Restore NV GPRs while returning from exception
eCryptfs: fix a couple type promotion bugs
intel_th: msu: Fix single mode with disabled IOMMU
Bluetooth: Add SMP workaround Microsoft Surface Precision Mouse bug
usb: Handle USB3 remote wakeup for LPM enabled devices correctly
dm bufio: fix deadlock with loop device
compiler.h, kasan: Avoid duplicating __read_once_size_nocheck()
compiler.h: Add read_word_at_a_time() function.
lib/strscpy: Shut up KASAN false-positives in strscpy()
ext4: allow directory holes
bnx2x: Prevent load reordering in tx completion processing
bnx2x: Prevent ptp_task to be rescheduled indefinitely
caif-hsi: fix possible deadlock in cfhsi_exit_module()
igmp: fix memory leak in igmpv3_del_delrec()
ipv4: don't set IPv6 only flags to IPv4 addresses
net: bcmgenet: use promisc for unsupported filters
net: dsa: mv88e6xxx: wait after reset deactivation
net: neigh: fix multiple neigh timer scheduling
net: openvswitch: fix csum updates for MPLS actions
nfc: fix potential illegal memory access
rxrpc: Fix send on a connected, but unbound socket
sky2: Disable MSI on ASUS P6T
vrf: make sure skb->data contains ip header to make routing
macsec: fix use-after-free of skb during RX
macsec: fix checksumming after decryption
netrom: fix a memory leak in nr_rx_frame()
netrom: hold sock when setting skb->destructor
bonding: validate ip header before check IPPROTO_IGMP
tcp: Reset bytes_acked and bytes_received when disconnecting
net: bridge: mcast: fix stale nsrcs pointer in igmp3/mld2 report handling
net: bridge: mcast: fix stale ipv6 hdr pointer when handling v6 query
net: bridge: stp: don't cache eth dest pointer before skb pull
perf/x86/amd/uncore: Rename 'L2' to 'LLC'
perf/x86/amd/uncore: Get correct number of cores sharing last level cache
perf/events/amd/uncore: Fix amd_uncore_llc ID to use pre-defined cpu_llc_id
NFSv4: Fix open create exclusive when the server reboots
nfsd: increase DRC cache limit
nfsd: give out fewer session slots as limit approaches
nfsd: fix performance-limiting session calculation
nfsd: Fix overflow causing non-working mounts on 1 TB machines
drm/panel: simple: Fix panel_simple_dsi_probe
usb: core: hub: Disable hub-initiated U1/U2
tty: max310x: Fix invalid baudrate divisors calculator
pinctrl: rockchip: fix leaked of_node references
tty: serial: cpm_uart - fix init when SMC is relocated
drm/bridge: tc358767: read display_props in get_modes()
drm/bridge: sii902x: pixel clock unit is 10kHz instead of 1kHz
memstick: Fix error cleanup path of memstick_init
tty/serial: digicolor: Fix digicolor-usart already registered warning
tty: serial: msm_serial: avoid system lockup condition
serial: 8250: Fix TX interrupt handling condition
drm/virtio: Add memory barriers for capset cache.
phy: renesas: rcar-gen2: Fix memory leak at error paths
drm/rockchip: Properly adjust to a true clock in adjusted_mode
tty: serial_core: Set port active bit in uart_port_activate
usb: gadget: Zero ffs_io_data
powerpc/pci/of: Fix OF flags parsing for 64bit BARs
PCI: sysfs: Ignore lockdep for remove attribute
kbuild: Add -Werror=unknown-warning-option to CLANG_FLAGS
PCI: xilinx-nwl: Fix Multi MSI data programming
iio: iio-utils: Fix possible incorrect mask calculation
recordmcount: Fix spurious mcount entries on powerpc
mfd: core: Set fwnode for created devices
mfd: arizona: Fix undefined behavior
mfd: hi655x-pmic: Fix missing return value check for devm_regmap_init_mmio_clk
um: Silence lockdep complaint about mmap_sem
powerpc/4xx/uic: clear pending interrupt after irq type/pol change
RDMA/i40iw: Set queue pair state when being queried
serial: sh-sci: Terminate TX DMA during buffer flushing
serial: sh-sci: Fix TX DMA buffer flushing and workqueue races
kallsyms: exclude kasan local symbols on s390
perf test mmap-thread-lookup: Initialize variable to suppress memory sanitizer warning
RDMA/rxe: Fill in wc byte_len with IB_WC_RECV_RDMA_WITH_IMM
powerpc/boot: add {get, put}_unaligned_be32 to xz_config.h
f2fs: avoid out-of-range memory access
mailbox: handle failed named mailbox channel request
powerpc/eeh: Handle hugepages in ioremap space
sh: prevent warnings when using iounmap
mm/kmemleak.c: fix check for softirq context
9p: pass the correct prototype to read_cache_page
mm/mmu_notifier: use hlist_add_head_rcu()
locking/lockdep: Fix lock used or unused stats error
locking/lockdep: Hide unused 'class' variable
usb: wusbcore: fix unbalanced get/put cluster_id
usb: pci-quirks: Correct AMD PLL quirk detection
x86/sysfb_efi: Add quirks for some devices with swapped width and height
x86/speculation/mds: Apply more accurate check on hypervisor platform
hpet: Fix division by zero in hpet_time_div()
ALSA: line6: Fix wrong altsetting for LINE6_PODHD500_1
ALSA: hda - Add a conexant codec entry to let mute led work
powerpc/tm: Fix oops on sigreturn on systems without TM
access: avoid the RCU grace period for the temporary subjective credentials
ipv6: check sk sk_type and protocol early in ip_mroute_set/getsockopt
tcp: reset sk_send_head in tcp_write_queue_purge
arm64: dts: marvell: Fix A37xx UART0 register size
i2c: qup: fixed releasing dma without flush operation completion
arm64: compat: Provide definition for COMPAT_SIGMINSTKSZ
ISDN: hfcsusb: checking idx of ep configuration
media: au0828: fix null dereference in error path
media: cpia2_usb: first wake up, then free in disconnect
media: radio-raremono: change devm_k*alloc to k*alloc
Bluetooth: hci_uart: check for missing tty operations
sched/fair: Don't free p->numa_faults with concurrent readers
drivers/pps/pps.c: clear offset flags in PPS_SETPARAMS ioctl
ceph: hold i_ceph_lock when removing caps for freeing inode
Linux 4.9.187
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
[ Upstream commit 7f1e541fc8d57a143dd5df1d0a1276046e08c083 ]
Sometimes we know that it's safe to do potentially out-of-bounds access
because we know it won't cross a page boundary. Still, KASAN will
report this as a bug.
Add read_word_at_a_time() function which is supposed to be used in such
cases. In read_word_at_a_time() KASAN performs relaxed check - only the
first byte of access is validated.
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit bdb5ac801af3d81d36732c2f640d6a1d3df83826 ]
Instead of having two identical __read_once_size_nocheck() functions
with different attributes, consolidate all the difference in new macro
__no_kasan_or_inline and use it. No functional changes.
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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Merge 4.9.185 into android-4.9-q
Changes in 4.9.185
tracing: Silence GCC 9 array bounds warning
gcc-9: silence 'address-of-packed-member' warning
scsi: ufs: Avoid runtime suspend possibly being blocked forever
usb: chipidea: udc: workaround for endpoint conflict issue
IB/hfi1: Silence txreq allocation warnings
Input: uinput - add compat ioctl number translation for UI_*_FF_UPLOAD
apparmor: enforce nullbyte at end of tag string
ARC: fix build warnings with !CONFIG_KPROBES
parport: Fix mem leak in parport_register_dev_model
parisc: Fix compiler warnings in float emulation code
IB/rdmavt: Fix alloc_qpn() WARN_ON()
IB/hfi1: Insure freeze_work work_struct is canceled on shutdown
IB/{qib, hfi1, rdmavt}: Correct ibv_devinfo max_mr value
MIPS: uprobes: remove set but not used variable 'epc'
net: dsa: mv88e6xxx: avoid error message on remove from VLAN 0
net: hns: Fix loopback test failed at copper ports
sparc: perf: fix updated event period in response to PERF_EVENT_IOC_PERIOD
net: ethernet: mediatek: Use hw_feature to judge if HWLRO is supported
net: ethernet: mediatek: Use NET_IP_ALIGN to judge if HW RX_2BYTE_OFFSET is enabled
drm/arm/hdlcd: Allow a bit of clock tolerance
scripts/checkstack.pl: Fix arm64 wrong or unknown architecture
scsi: ufs: Check that space was properly alloced in copy_query_response
s390/qeth: fix VLAN attribute in bridge_hostnotify udev event
hwmon: (pmbus/core) Treat parameters as paged if on multiple pages
nvme: Fix u32 overflow in the number of namespace list calculation
btrfs: start readahead also in seed devices
can: flexcan: fix timeout when set small bitrate
can: purge socket error queue on sock destruct
powerpc/bpf: use unsigned division instruction for 64-bit operations
ARM: imx: cpuidle-imx6sx: Restrict the SW2ISO increase to i.MX6SX
Bluetooth: Align minimum encryption key size for LE and BR/EDR connections
Bluetooth: Fix regression with minimum encryption key size alignment
cfg80211: fix memory leak of wiphy device name
mac80211: drop robust management frames from unknown TA
mac80211: Do not use stack memory with scatterlist for GMAC
IB/hfi1: Avoid hardlockup with flushlist_lock
perf ui helpline: Use strlcpy() as a shorter form of strncpy() + explicit set nul
perf help: Remove needless use of strncpy()
perf header: Fix unchecked usage of strncpy()
9p/rdma: do not disconnect on down_interruptible EAGAIN
9p: acl: fix uninitialized iattr access
9p/rdma: remove useless check in cm_event_handler
9p: p9dirent_read: check network-provided name length
net/9p: include trans_common.h to fix missing prototype warning.
fs/proc/array.c: allow reporting eip/esp for all coredumping threads
fs/binfmt_flat.c: make load_flat_shared_library() work
mm/page_idle.c: fix oops because end_pfn is larger than max_pfn
scsi: vmw_pscsi: Fix use-after-free in pvscsi_queue_lck()
x86/speculation: Allow guests to use SSBD even if host does not
NFS/flexfiles: Use the correct TCP timeout for flexfiles I/O
cpu/speculation: Warn on unsupported mitigations= parameter
af_packet: Block execution of tasks waiting for transmit to complete in AF_PACKET
net: stmmac: fixed new system time seconds value calculation
sctp: change to hold sk after auth shkey is created successfully
tipc: change to use register_pernet_device
tipc: check msg->req data len in tipc_nl_compat_bearer_disable
tun: wake up waitqueues after IFF_UP is set
team: Always enable vlan tx offload
bonding: Always enable vlan tx offload
ipv4: Use return value of inet_iif() for __raw_v4_lookup in the while loop
net: check before dereferencing netdev_ops during busy poll
bpf: udp: Avoid calling reuseport's bpf_prog from udp_gro
bpf: udp: ipv6: Avoid running reuseport's bpf_prog from __udp6_lib_err
tipc: pass tunnel dev as NULL to udp_tunnel(6)_xmit_skb
Bluetooth: Fix faulty expression for minimum encryption key size check
ASoC : cs4265 : readable register too low
ASoC: soc-pcm: BE dai needs prepare when pause release after resume
spi: bitbang: Fix NULL pointer dereference in spi_unregister_master
drm/mediatek: fix unbind functions
ASoC: max98090: remove 24-bit format support if RJ is 0
usb: gadget: fusb300_udc: Fix memory leak of fusb300->ep[i]
usb: gadget: udc: lpc32xx: allocate descriptor with GFP_ATOMIC
scsi: hpsa: correct ioaccel2 chaining
scripts/decode_stacktrace.sh: prefix addr2line with $CROSS_COMPILE
mm/mlock.c: change count_mm_mlocked_page_nr return type
MIPS: math-emu: do not use bools for arithmetic
MIPS: netlogic: xlr: Remove erroneous check in nlm_fmn_send()
mfd: omap-usb-tll: Fix register offsets
ARC: fix allnoconfig build warning
bug.h: work around GCC PR82365 in BUG()
ARC: handle gcc generated __builtin_trap for older compiler
clk: sunxi: fix uninitialized access
KVM: x86: degrade WARN to pr_warn_ratelimited
drm/i915/dmc: protect against reading random memory
MIPS: Workaround GCC __builtin_unreachable reordering bug
ptrace: Fix ->ptracer_cred handling for PTRACE_TRACEME
crypto: user - prevent operating on larval algorithms
ALSA: seq: fix incorrect order of dest_client/dest_ports arguments
ALSA: firewire-lib/fireworks: fix miss detection of received MIDI messages
ALSA: line6: Fix write on zero-sized buffer
ALSA: usb-audio: fix sign unintended sign extension on left shifts
lib/mpi: Fix karactx leak in mpi_powm
drm/imx: notify drm core before sending event during crtc disable
drm/imx: only send event on crtc disable if kept disabled
btrfs: Ensure replaced device doesn't have pending chunk allocation
tty: rocket: fix incorrect forward declaration of 'rp_init()'
arm64, vdso: Define vdso_{start,end} as array
KVM: LAPIC: Fix pending interrupt in IRR blocked by software disable LAPIC
IB/hfi1: Close PSM sdma_progress sleep window
MIPS: Add missing EHB in mtc0 -> mfc0 sequence.
dmaengine: imx-sdma: remove BD_INTR for channel0
arm64: kaslr: keep modules inside module region when KASAN is enabled
Linux 4.9.185
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
[ Upstream commit 173a3efd3edb2ef6ef07471397c5f542a360e9c1 ]
Looking at functions with large stack frames across all architectures
led me discovering that BUG() suffers from the same problem as
fortify_panic(), which I've added a workaround for already.
In short, variables that go out of scope by calling a noreturn function
or __builtin_unreachable() keep using stack space in functions
afterwards.
A workaround that was identified is to insert an empty assembler
statement just before calling the function that doesn't return. I'm
adding a macro "barrier_before_unreachable()" to document this, and
insert calls to that in all instances of BUG() that currently suffer
from this problem.
The files that saw the largest change from this had these frame sizes
before, and much less with my patch:
fs/ext4/inode.c:82:1: warning: the frame size of 1672 bytes is larger than 800 bytes [-Wframe-larger-than=]
fs/ext4/namei.c:434:1: warning: the frame size of 904 bytes is larger than 800 bytes [-Wframe-larger-than=]
fs/ext4/super.c:2279:1: warning: the frame size of 1160 bytes is larger than 800 bytes [-Wframe-larger-than=]
fs/ext4/xattr.c:146:1: warning: the frame size of 1168 bytes is larger than 800 bytes [-Wframe-larger-than=]
fs/f2fs/inode.c:152:1: warning: the frame size of 1424 bytes is larger than 800 bytes [-Wframe-larger-than=]
net/netfilter/ipvs/ip_vs_core.c:1195:1: warning: the frame size of 1068 bytes is larger than 800 bytes [-Wframe-larger-than=]
net/netfilter/ipvs/ip_vs_core.c:395:1: warning: the frame size of 1084 bytes is larger than 800 bytes [-Wframe-larger-than=]
net/netfilter/ipvs/ip_vs_ftp.c:298:1: warning: the frame size of 928 bytes is larger than 800 bytes [-Wframe-larger-than=]
net/netfilter/ipvs/ip_vs_ftp.c:418:1: warning: the frame size of 908 bytes is larger than 800 bytes [-Wframe-larger-than=]
net/netfilter/ipvs/ip_vs_lblcr.c:718:1: warning: the frame size of 960 bytes is larger than 800 bytes [-Wframe-larger-than=]
drivers/net/xen-netback/netback.c:1500:1: warning: the frame size of 1088 bytes is larger than 800 bytes [-Wframe-larger-than=]
In case of ARC and CRIS, it turns out that the BUG() implementation
actually does return (or at least the compiler thinks it does),
resulting in lots of warnings about uninitialized variable use and
leaving noreturn functions, such as:
block/cfq-iosched.c: In function 'cfq_async_queue_prio':
block/cfq-iosched.c:3804:1: error: control reaches end of non-void function [-Werror=return-type]
include/linux/dmaengine.h: In function 'dma_maxpq':
include/linux/dmaengine.h:1123:1: error: control reaches end of non-void function [-Werror=return-type]
This makes them call __builtin_trap() instead, which should normally
dump the stack and kill the current process, like some of the other
architectures already do.
I tried adding barrier_before_unreachable() to panic() and
fortify_panic() as well, but that had very little effect, so I'm not
submitting that patch.
Vineet said:
: For ARC, it is double win.
:
: 1. Fixes 3 -Wreturn-type warnings
:
: | ../net/core/ethtool.c:311:1: warning: control reaches end of non-void function
: [-Wreturn-type]
: | ../kernel/sched/core.c:3246:1: warning: control reaches end of non-void function
: [-Wreturn-type]
: | ../include/linux/sunrpc/svc_xprt.h:180:1: warning: control reaches end of
: non-void function [-Wreturn-type]
:
: 2. bloat-o-meter reports code size improvements as gcc elides the
: generated code for stack return.
Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82365
Link: http://lkml.kernel.org/r/20171219114112.939391-1-arnd@arndb.de
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Vineet Gupta <vgupta@synopsys.com> [arch/arc]
Tested-by: Vineet Gupta <vgupta@synopsys.com> [arch/arc]
Cc: Mikael Starvik <starvik@axis.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Christopher Li <sparse@chrisli.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: "Steven Rostedt (VMware)" <rostedt@goodmis.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[removed cris chunks - gregkh]
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge 4.9.111 into android-4.9
Changes in 4.9.111
x86/spectre_v1: Disable compiler optimizations over array_index_mask_nospec()
x86/mce: Improve error message when kernel cannot recover
x86/mce: Check for alternate indication of machine check recovery on Skylake
x86/mce: Fix incorrect "Machine check from unknown source" message
x86/mce: Do not overwrite MCi_STATUS in mce_no_way_out()
x86: Call fixup_exception() before notify_die() in math_error()
m68k/mm: Adjust VM area to be unmapped by gap size for __iounmap()
serial: sh-sci: Use spin_{try}lock_irqsave instead of open coding version
signal/xtensa: Consistenly use SIGBUS in do_unaligned_user
usb: do not reset if a low-speed or full-speed device timed out
1wire: family module autoload fails because of upper/lower case mismatch.
ASoC: dapm: delete dapm_kcontrol_data paths list before freeing it
ASoC: cirrus: i2s: Fix LRCLK configuration
ASoC: cirrus: i2s: Fix {TX|RX}LinCtrlData setup
clk: renesas: cpg-mssr: Stop using printk format %pCr
lib/vsprintf: Remove atomic-unsafe support for %pCr
mips: ftrace: fix static function graph tracing
branch-check: fix long->int truncation when profiling branches
ipmi:bt: Set the timeout before doing a capabilities check
Bluetooth: hci_qca: Avoid missing rampatch failure with userspace fw loader
fuse: atomic_o_trunc should truncate pagecache
fuse: don't keep dead fuse_conn at fuse_fill_super().
fuse: fix control dir setup and teardown
powerpc/mm/hash: Add missing isync prior to kernel stack SLB switch
powerpc/ptrace: Fix setting 512B aligned breakpoints with PTRACE_SET_DEBUGREG
powerpc/ptrace: Fix enforcement of DAWR constraints
powerpc/powernv/ioda2: Remove redundant free of TCE pages
cpuidle: powernv: Fix promotion from snooze if next state disabled
powerpc/fadump: Unregister fadump on kexec down path.
ARM: 8764/1: kgdb: fix NUMREGBYTES so that gdb_regs[] is the correct size
arm64: kpti: Use early_param for kpti= command-line option
arm64: mm: Ensure writes to swapper are ordered wrt subsequent cache maintenance
of: unittest: for strings, account for trailing \0 in property length field
IB/qib: Fix DMA api warning with debug kernel
IB/{hfi1, qib}: Add handling of kernel restart
IB/mlx5: Fetch soft WQE's on fatal error state
IB/isert: Fix for lib/dma_debug check_sync warning
IB/isert: fix T10-pi check mask setting
RDMA/mlx4: Discard unknown SQP work requests
mtd: cfi_cmdset_0002: Change write buffer to check correct value
mtd: cfi_cmdset_0002: Use right chip in do_ppb_xxlock()
mtd: cfi_cmdset_0002: fix SEGV unlocking multiple chips
mtd: cfi_cmdset_0002: Fix unlocking requests crossing a chip boudary
mtd: cfi_cmdset_0002: Avoid walking all chips when unlocking.
MIPS: BCM47XX: Enable 74K Core ExternalSync for PCIe erratum
PCI: Add ACS quirk for Intel 7th & 8th Gen mobile
PCI: Add ACS quirk for Intel 300 series
PCI: pciehp: Clear Presence Detect and Data Link Layer Status Changed on resume
printk: fix possible reuse of va_list variable
MIPS: io: Add barrier after register read in inX()
time: Make sure jiffies_to_msecs() preserves non-zero time periods
X.509: unpack RSA signatureValue field from BIT STRING
Btrfs: fix return value on rename exchange failure
Btrfs: fix unexpected cow in run_delalloc_nocow
iio:buffer: make length types match kfifo types
scsi: qla2xxx: Fix setting lower transfer speed if GPSC fails
scsi: zfcp: fix missing SCSI trace for result of eh_host_reset_handler
scsi: zfcp: fix missing SCSI trace for retry of abort / scsi_eh TMF
scsi: zfcp: fix misleading REC trigger trace where erp_action setup failed
scsi: zfcp: fix missing REC trigger trace on terminate_rport_io early return
scsi: zfcp: fix missing REC trigger trace on terminate_rport_io for ERP_FAILED
scsi: zfcp: fix missing REC trigger trace for all objects in ERP_FAILED
scsi: zfcp: fix missing REC trigger trace on enqueue without ERP thread
linvdimm, pmem: Preserve read-only setting for pmem devices
clk: at91: PLL recalc_rate() now using cached MUL and DIV values
md: fix two problems with setting the "re-add" device state.
rpmsg: smd: do not use mananged resources for endpoints and channels
ubi: fastmap: Cancel work upon detach
ubi: fastmap: Correctly handle interrupted erasures in EBA
UBIFS: Fix potential integer overflow in allocation
backlight: as3711_bl: Fix Device Tree node lookup
backlight: max8925_bl: Fix Device Tree node lookup
backlight: tps65217_bl: Fix Device Tree node lookup
mfd: intel-lpss: Program REMAP register in PIO mode
perf tools: Fix symbol and object code resolution for vdso32 and vdsox32
perf intel-pt: Fix sync_switch INTEL_PT_SS_NOT_TRACING
perf intel-pt: Fix decoding to accept CBR between FUP and corresponding TIP
perf intel-pt: Fix MTC timing after overflow
perf intel-pt: Fix "Unexpected indirect branch" error
perf intel-pt: Fix packet decoding of CYC packets
media: v4l2-compat-ioctl32: prevent go past max size
media: cx231xx: Add support for AverMedia DVD EZMaker 7
media: dvb_frontend: fix locking issues at dvb_frontend_get_event()
nfsd: restrict rd_maxcount to svc_max_payload in nfsd_encode_readdir
NFSv4: Fix possible 1-byte stack overflow in nfs_idmap_read_and_verify_message
NFSv4: Revert commit 5f83d86cf5 ("NFSv4.x: Fix wraparound issues..")
video: uvesafb: Fix integer overflow in allocation
Input: elan_i2c - add ELAN0618 (Lenovo v330 15IKB) ACPI ID
pwm: lpss: platform: Save/restore the ctrl register over a suspend/resume
rbd: flush rbd_dev->watch_dwork after watch is unregistered
mm: fix devmem_is_allowed() for sub-page System RAM intersections
xen: Remove unnecessary BUG_ON from __unbind_from_irq()
udf: Detect incorrect directory size
Input: elan_i2c_smbus - fix more potential stack buffer overflows
Input: elantech - enable middle button of touchpads on ThinkPad P52
Input: elantech - fix V4 report decoding for module with middle key
ALSA: hda/realtek - Fix pop noise on Lenovo P50 & co
ALSA: hda/realtek - Add a quirk for FSC ESPRIMO U9210
block: Fix transfer when chunk sectors exceeds max
dm thin: handle running out of data space vs concurrent discard
cdc_ncm: avoid padding beyond end of skb
Linux 4.9.111
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
commit 2026d35741f2c3ece73c11eb7e4a15d7c2df9ebe upstream.
The function __builtin_expect returns long type (see the gcc
documentation), and so do macros likely and unlikely. Unfortunatelly, when
CONFIG_PROFILE_ANNOTATED_BRANCHES is selected, the macros likely and
unlikely expand to __branch_check__ and __branch_check__ truncates the
long type to int. This unintended truncation may cause bugs in various
kernel code (we found a bug in dm-writecache because of it), so it's
better to fix __branch_check__ to return long.
Link: http://lkml.kernel.org/r/alpine.LRH.2.02.1805300818140.24812@file01.intranet.prod.int.rdu2.redhat.com
Cc: Ingo Molnar <mingo@redhat.com>
Cc: stable@vger.kernel.org
Fixes: 1f0d69a9fc ("tracing: profile likely and unlikely annotations")
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This change adds the CONFIG_CFI_CLANG option, CFI error handling,
and a faster look-up table for cross module CFI checks.
Bug: 67506682
Change-Id: Ic009f0a629b552a0eb16e6d89808c7029e91447d
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
With CONFIG_LTO_CLANG enabled, LLVM IR won't be compiled into object
files until modpost_link. This change postpones calls to recordmcount
until after this step.
In order to exclude ftrace_process_locs from inspection, we add a new
code section .text..ftrace, which we tell recordmcount to ignore, and
a __norecordmcount attribute for moving functions to this section.
Bug: 62093296
Bug: 67506682
Change-Id: Iba2c053968206acf533fadab1eb34a743b5088ee
(am from https://patchwork.kernel.org/patch/10060327/)
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
commit df5d45aa08f848b79caf395211b222790534ccc7 upstream.
Create a new function attribute __optimize, which allows to specify an
optimization level on a per-function basis.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
extract as much possible uncertainty from a running system at boot time as
possible, hoping to capitalize on any possible variation in CPU operation
(due to runtime data differences, hardware differences, SMP ordering,
thermal timing variation, cache behavior, etc).
At the very least, this plugin is a much more comprehensive example for
how to manipulate kernel code using the gcc plugin internals.
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Merge tag 'gcc-plugins-v4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull gcc plugins update from Kees Cook:
"This adds a new gcc plugin named "latent_entropy". It is designed to
extract as much possible uncertainty from a running system at boot
time as possible, hoping to capitalize on any possible variation in
CPU operation (due to runtime data differences, hardware differences,
SMP ordering, thermal timing variation, cache behavior, etc).
At the very least, this plugin is a much more comprehensive example
for how to manipulate kernel code using the gcc plugin internals"
* tag 'gcc-plugins-v4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
latent_entropy: Mark functions with __latent_entropy
gcc-plugins: Add latent_entropy plugin
Pull kbuild updates from Michal Marek:
- EXPORT_SYMBOL for asm source by Al Viro.
This does bring a regression, because genksyms no longer generates
checksums for these symbols (CONFIG_MODVERSIONS). Nick Piggin is
working on a patch to fix this.
Plus, we are talking about functions like strcpy(), which rarely
change prototypes.
- Fixes for PPC fallout of the above by Stephen Rothwell and Nick
Piggin
- fixdep speedup by Alexey Dobriyan.
- preparatory work by Nick Piggin to allow architectures to build with
-ffunction-sections, -fdata-sections and --gc-sections
- CONFIG_THIN_ARCHIVES support by Stephen Rothwell
- fix for filenames with colons in the initramfs source by me.
* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild: (22 commits)
initramfs: Escape colons in depfile
ppc: there is no clear_pages to export
powerpc/64: whitelist unresolved modversions CRCs
kbuild: -ffunction-sections fix for archs with conflicting sections
kbuild: add arch specific post-link Makefile
kbuild: allow archs to select link dead code/data elimination
kbuild: allow architectures to use thin archives instead of ld -r
kbuild: Regenerate genksyms lexer
kbuild: genksyms fix for typeof handling
fixdep: faster CONFIG_ search
ia64: move exports to definitions
sparc32: debride memcpy.S a bit
[sparc] unify 32bit and 64bit string.h
sparc: move exports to definitions
ppc: move exports to definitions
arm: move exports to definitions
s390: move exports to definitions
m68k: move exports to definitions
alpha: move exports to actual definitions
x86: move exports to actual definitions
...
The __latent_entropy gcc attribute can be used only on functions and
variables. If it is on a function then the plugin will instrument it for
gathering control-flow entropy. If the attribute is on a variable then
the plugin will initialize it with random contents. The variable must
be an integer, an integer array type or a structure with integer fields.
These specific functions have been selected because they are init
functions (to help gather boot-time entropy), are called at unpredictable
times, or they have variable loops, each of which provide some level of
latent entropy.
Signed-off-by: Emese Revfy <re.emese@gmail.com>
[kees: expanded commit message]
Signed-off-by: Kees Cook <keescook@chromium.org>
Introduce LD_DEAD_CODE_DATA_ELIMINATION option for architectures to
select to build with -ffunction-sections, -fdata-sections, and link
with --gc-sections. It requires some work (documented) to ensure all
unreferenced entrypoints are live, and requires toolchain and build
verification, so it is made a per-arch option for now.
On a random powerpc64le build, this yelds a significant size saving,
it boots and runs fine, but there is a lot I haven't tested as yet, so
these savings may be reduced if there are bugs in the link.
text data bss dec filename
11169741 1180744 1923176 14273661 vmlinux
10445269 1004127 1919707 13369103 vmlinux.dce
~700K text, ~170K data, 6% removed from kernel image size.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
My previous commit:
112dc0c806 ("locking/barriers: Suppress sparse warnings in lockless_dereference()")
caused sparse to complain that (in radix-tree.h) we use sizeof(void)
since that rcu_dereference()s a void *.
Really, all we need is to have the expression *p in here somewhere
to make sure p is a pointer type, and sizeof(*p) was the thing that
came to my mind first to make sure that's done without really doing
anything at runtime.
Another thing I had considered was using typeof(*p), but obviously
we can't just declare a typeof(*p) variable either, since that may
end up being void. Declaring a variable as typeof(*p)* gets around
that, and still checks that typeof(*p) is valid, so do that. This
type construction can't be done for _________p1 because that will
actually be used and causes sparse address space warnings, so keep
a separate unused variable for it.
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E . McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kbuild-all@01.org
Fixes: 112dc0c806 ("locking/barriers: Suppress sparse warnings in lockless_dereference()")
Link: http://lkml.kernel.org/r/1472192160-4049-1-git-send-email-johannes@sipsolutions.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
After Peter's commit:
331b6d8c7a ("locking/barriers: Validate lockless_dereference() is used on a pointer type")
... we get a lot of sparse warnings (one for every rcu_dereference, and more)
since the expression here is assigning to the wrong address space.
Instead of validating that 'p' is a pointer this way, instead make
it fail compilation when it's not by using sizeof(*(p)). This will
not cause any sparse warnings (tested, likely since the address
space is irrelevant for sizeof), and will fail compilation when
'p' isn't a pointer type.
Tested-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 331b6d8c7a ("locking/barriers: Validate lockless_dereference() is used on a pointer type")
Link: http://lkml.kernel.org/r/1470909022-687-2-git-send-email-johannes@sipsolutions.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
1/ Replace pcommit with ADR / directed-flushing:
The pcommit instruction, which has not shipped on any product, is
deprecated. Instead, the requirement is that platforms implement either
ADR, or provide one or more flush addresses per nvdimm. ADR
(Asynchronous DRAM Refresh) flushes data in posted write buffers to the
memory controller on a power-fail event. Flush addresses are defined in
ACPI 6.x as an NVDIMM Firmware Interface Table (NFIT) sub-structure:
"Flush Hint Address Structure". A flush hint is an mmio address that
when written and fenced assures that all previous posted writes
targeting a given dimm have been flushed to media.
2/ On-demand ARS (address range scrub):
Linux uses the results of the ACPI ARS commands to track bad blocks
in pmem devices. When latent errors are detected we re-scrub the media
to refresh the bad block list, userspace can also request a re-scrub at
any time.
3/ Support for the Microsoft DSM (device specific method) command format.
4/ Support for EDK2/OVMF virtual disk device memory ranges.
5/ Various fixes and cleanups across the subsystem.
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Merge tag 'libnvdimm-for-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
Pull libnvdimm updates from Dan Williams:
- Replace pcommit with ADR / directed-flushing.
The pcommit instruction, which has not shipped on any product, is
deprecated. Instead, the requirement is that platforms implement
either ADR, or provide one or more flush addresses per nvdimm.
ADR (Asynchronous DRAM Refresh) flushes data in posted write buffers
to the memory controller on a power-fail event.
Flush addresses are defined in ACPI 6.x as an NVDIMM Firmware
Interface Table (NFIT) sub-structure: "Flush Hint Address Structure".
A flush hint is an mmio address that when written and fenced assures
that all previous posted writes targeting a given dimm have been
flushed to media.
- On-demand ARS (address range scrub).
Linux uses the results of the ACPI ARS commands to track bad blocks
in pmem devices. When latent errors are detected we re-scrub the
media to refresh the bad block list, userspace can also request a
re-scrub at any time.
- Support for the Microsoft DSM (device specific method) command
format.
- Support for EDK2/OVMF virtual disk device memory ranges.
- Various fixes and cleanups across the subsystem.
* tag 'libnvdimm-for-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (41 commits)
libnvdimm-btt: Delete an unnecessary check before the function call "__nd_device_register"
nfit: do an ARS scrub on hitting a latent media error
nfit: move to nfit/ sub-directory
nfit, libnvdimm: allow an ARS scrub to be triggered on demand
libnvdimm: register nvdimm_bus devices with an nd_bus driver
pmem: clarify a debug print in pmem_clear_poison
x86/insn: remove pcommit
Revert "KVM: x86: add pcommit support"
nfit, tools/testing/nvdimm/: unify shutdown paths
libnvdimm: move ->module to struct nvdimm_bus_descriptor
nfit: cleanup acpi_nfit_init calling convention
nfit: fix _FIT evaluation memory leak + use after free
tools/testing/nvdimm: add manufacturing_{date|location} dimm properties
tools/testing/nvdimm: add virtual ramdisk range
acpi, nfit: treat virtual ramdisk SPA as pmem region
pmem: kill __pmem address space
pmem: kill wmb_pmem()
libnvdimm, pmem: use nvdimm_flush() for namespace I/O writes
fs/dax: remove wmb_pmem()
libnvdimm, pmem: flush posted-write queues on shutdown
...
The __pmem address space was meant to annotate codepaths that touch
persistent memory and need to coordinate a call to wmb_pmem(). Now that
wmb_pmem() is gone, there is little need to keep this annotation.
Cc: Christoph Hellwig <hch@lst.de>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Since all asm/barrier.h should/must include asm-generic/barrier.h the
latter is a good place for generic infrastructure like this.
This also allows archs to override the new smp_acquire__after_ctrl_dep().
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Introduce smp_acquire__after_ctrl_dep(), this construct is not
uncommon, but the lack of this barrier is.
Use it to better express smp_rmb() uses in WRITE_ONCE(), the IPC
semaphore code and the qspinlock code.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This new form allows using hardware assisted waiting.
Some hardware (ARM64 and x86) allow monitoring an address for changes,
so by providing a pointer we can use this to replace the cpu_relax()
with hardware optimized methods in the future.
Requested-by: Will Deacon <will.deacon@arm.com>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Use the type to validate the argument @p is indeed a pointer type.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20160522104827.GP3193@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
gcc as far back as at least 3.04 documents the function attribute
__malloc__. Add a shorthand for attaching that to a function
declaration. This was also suggested by Andi Kleen way back in 2002
[1], but didn't get applied, perhaps because gcc at that time generated
the exact same code with and without this attribute.
This attribute tells the compiler that the return value (if non-NULL)
can be assumed not to alias any other valid pointers at the time of the
call.
Please note that the documentation for a range of gcc versions (starting
from around 4.7) contained a somewhat confusing and self-contradicting
text:
The malloc attribute is used to tell the compiler that a function may
be treated as if any non-NULL pointer it returns cannot alias any other
pointer valid when the function returns and *that the memory has
undefined content*. [...] Standard functions with this property include
malloc and *calloc*.
(emphasis mine). The intended meaning has later been clarified [2]:
This tells the compiler that a function is malloc-like, i.e., that the
pointer P returned by the function cannot alias any other pointer valid
when the function returns, and moreover no pointers to valid objects
occur in any storage addressed by P.
What this means is that we can apply the attribute to kmalloc and
friends, and it is ok for the returned memory to have well-defined
contents (__GFP_ZERO). But it is not ok to apply it to kmemdup(), nor
to other functions which both allocate and possibly initialize the
memory with existing pointers. So unless someone is doing something
pretty perverted kstrdup() should also be a fine candidate.
[1] http://thread.gmane.org/gmane.linux.kernel/57172
[2] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=56955
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
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: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In C programming language, we don't have a easy way to privatize a
member of a structure. However in kernel, sometimes there is a need to
privatize a member in case of potential bugs or misuses.
Fortunately, the noderef attribute of sparse is a way to privatize a
member, as by defining a member as noderef, the address-of operator on
the member will produce a noderef pointer to that member, and if anyone
wants to dereference that kind of pointers to read or modify the member,
sparse will yell.
Based on this, __private modifier and related operation ACCESS_PRIVATE()
are introduced, which could help detect undesigned public uses of
private members of structs. Here is an example of sparse's output if it
detect an undersigned public use:
| kernel/rcu/tree.c:4453:25: warning: incorrect type in argument 1 (different modifiers)
| kernel/rcu/tree.c:4453:25: expected struct raw_spinlock [usertype] *lock
| kernel/rcu/tree.c:4453:25: got struct raw_spinlock [noderef] *<noident>
Also, this patch improves compiler.h a little bit by adding comments for
"#else" and "#endif".
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
In my randconfig tests, I came across a bug that involves several
components:
* gcc-4.9 through at least 5.3
* CONFIG_GCOV_PROFILE_ALL enabling -fprofile-arcs for all files
* CONFIG_PROFILE_ALL_BRANCHES overriding every if()
* The optimized implementation of do_div() that tries to
replace a library call with an division by multiplication
* code in drivers/media/dvb-frontends/zl10353.c doing
u32 adc_clock = 450560; /* 45.056 MHz */
if (state->config.adc_clock)
adc_clock = state->config.adc_clock;
do_div(value, adc_clock);
In this case, gcc fails to determine whether the divisor
in do_div() is __builtin_constant_p(). In particular, it
concludes that __builtin_constant_p(adc_clock) is false, while
__builtin_constant_p(!!adc_clock) is true.
That in turn throws off the logic in do_div() that also uses
__builtin_constant_p(), and instead of picking either the
constant- optimized division, and the code in ilog2() that uses
__builtin_constant_p() to figure out whether it knows the answer at
compile time. The result is a link error from failing to find
multiple symbols that should never have been called based on
the __builtin_constant_p():
dvb-frontends/zl10353.c:138: undefined reference to `____ilog2_NaN'
dvb-frontends/zl10353.c:138: undefined reference to `__aeabi_uldivmod'
ERROR: "____ilog2_NaN" [drivers/media/dvb-frontends/zl10353.ko] undefined!
ERROR: "__aeabi_uldivmod" [drivers/media/dvb-frontends/zl10353.ko] undefined!
This patch avoids the problem by changing __trace_if() to check
whether the condition is known at compile-time to be nonzero, rather
than checking whether it is actually a constant.
I see this one link error in roughly one out of 1600 randconfig builds
on ARM, and the patch fixes all known instances.
Link: http://lkml.kernel.org/r/1455312410-1058841-1-git-send-email-arnd@arndb.de
Acked-by: Nicolas Pitre <nico@linaro.org>
Fixes: ab3c9c686e ("branch tracer, intel-iommu: fix build with CONFIG_BRANCH_TRACER=y")
Cc: stable@vger.kernel.org # v2.6.30+
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
The comment is out of data. Also point out the performance drawback
of the barrier();__builtin_memcpy(); barrier() followed by another
copy from stack (__u) to lvalue;
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1453757600-11441-1-git-send-email-konrad.wilk@oracle.com
[ Made it a bit more readable. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Introduce smp_cond_acquire() which combines a control dependency and a
read barrier to form acquire semantics.
This primitive has two benefits:
- it documents control dependencies,
- its typically cheaper than using smp_load_acquire() in a loop.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
gcc 4.9 added the function attribute assume_aligned, indicating to the
caller that the returned pointer may be assumed to have a certain minimal
alignment. This is useful if, for example, the return value is passed to
memset(). Add a shorthand macro for that.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull s390 updates from Martin Schwidefsky:
"There is only one new feature in this pull for the 4.4 merge window,
most of it is small enhancements, cleanup and bug fixes:
- Add the s390 backend for the software dirty bit tracking. This
adds two new pgtable functions pte_clear_soft_dirty and
pmd_clear_soft_dirty which is why there is a hit to
arch/x86/include/asm/pgtable.h in this pull request.
- A series of cleanup patches for the AP bus, this includes the
removal of the support for two outdated crypto cards (PCICC and
PCICA).
- The irq handling / signaling on buffer full in the runtime
instrumentation code is dropped.
- Some micro optimizations: remove unnecessary memory barriers for a
couple of functions: [smb_]rmb, [smb_]wmb, atomics, bitops, and for
spin_unlock. Use the builtin bswap if available and make
test_and_set_bit_lock more cache friendly.
- Statistics and a tracepoint for the diagnose calls to the
hypervisor.
- The CPU measurement facility support to sample KVM guests is
improved.
- The vector instructions are now always enabled for user space
processes if the hardware has the vector facility. This simplifies
the FPU handling code. The fpu-internal.h header is split into fpu
internals, api and types just like x86.
- Cleanup and improvements for the common I/O layer.
- Rework udelay to solve a problem with kprobe. udelay has busy loop
semantics but still uses an idle processor state for the wait"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (66 commits)
s390: remove runtime instrumentation interrupts
s390/cio: de-duplicate subchannel validation
s390/css: unneeded initialization in for_each_subchannel
s390/Kconfig: use builtin bswap
s390/dasd: fix disconnected device with valid path mask
s390/dasd: fix invalid PAV assignment after suspend/resume
s390/dasd: fix double free in dasd_eckd_read_conf
s390/kernel: fix ptrace peek/poke for floating point registers
s390/cio: move ccw_device_stlck functions
s390/cio: move ccw_device_call_handler
s390/topology: reduce per_cpu() invocations
s390/nmi: reduce size of percpu variable
s390/nmi: fix terminology
s390/nmi: remove casts
s390/nmi: remove pointless error strings
s390: don't store registers on disabled wait anymore
s390: get rid of __set_psw_mask()
s390/fpu: split fpu-internal.h into fpu internals, api, and type headers
s390/dasd: fix list_del corruption after lcu changes
s390/spinlock: remove unneeded serializations at unlock
...
This seems to be a mis-reading of how alpha memory ordering works, and
is not backed up by the alpha architecture manual. The helper functions
don't do anything special on any other architectures, and the arguments
that support them being safe on other architectures also argue that they
are safe on alpha.
Basically, the "control dependency" is between a previous read and a
subsequent write that is dependent on the value read. Even if the
subsequent write is actually done speculatively, there is no way that
such a speculative write could be made visible to other cpu's until it
has been committed, which requires validating the speculation.
Note that most weakely ordered architectures (very much including alpha)
do not guarantee any ordering relationship between two loads that depend
on each other on a control dependency:
read A
if (val == 1)
read B
because the conditional may be predicted, and the "read B" may be
speculatively moved up to before reading the value A. So we require the
user to insert a smp_rmb() between the two accesses to be correct:
read A;
if (A == 1)
smp_rmb()
read B
Alpha is further special in that it can break that ordering even if the
*address* of B depends on the read of A, because the cacheline that is
read later may be stale unless you have a memory barrier in between the
pointer read and the read of the value behind a pointer:
read ptr
read offset(ptr)
whereas all other weakly ordered architectures guarantee that the data
dependency (as opposed to just a control dependency) will order the two
accesses. As a result, alpha needs a "smp_read_barrier_depends()" in
between those two reads for them to be ordered.
The coontrol dependency that "READ_ONCE_CTRL()" and "atomic_read_ctrl()"
had was a control dependency to a subsequent *write*, however, and
nobody can finalize such a subsequent write without having actually done
the read. And were you to write such a value to a "stale" cacheline
(the way the unordered reads came to be), that would seem to lose the
write entirely.
So the things that make alpha able to re-order reads even more
aggressively than other weak architectures do not seem to be relevant
for a subsequent write. Alpha memory ordering may be strange, but
there's no real indication that it is *that* strange.
Also, the alpha architecture reference manual very explicitly talks
about the definition of "Dependence Constraints" in section 5.6.1.7,
where a preceding read dominates a subsequent write.
Such a dependence constraint admittedly does not impose a BEFORE (alpha
architecture term for globally visible ordering), but it does guarantee
that there can be no "causal loop". I don't see how you could avoid
such a loop if another cpu could see the stored value and then impact
the value of the first read. Put another way: the read and the write
could not be seen as being out of order wrt other cpus.
So I do not see how these "x_ctrl()" functions can currently be necessary.
I may have to eat my words at some point, but in the absense of clear
proof that alpha actually needs this, or indeed even an explanation of
how alpha could _possibly_ need it, I do not believe these functions are
called for.
And if it turns out that alpha really _does_ need a barrier for this
case, that barrier still should not be "smp_read_barrier_depends()".
We'd have to make up some new speciality barrier just for alpha, along
with the documentation for why it really is necessary.
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul E McKenney <paulmck@us.ibm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Some code may perform racy by design memory reads. This could be
harmless, yet such code may produce KASAN warnings.
To hide such accesses from KASAN this patch introduces
READ_ONCE_NOCHECK() macro. KASAN will not check the memory
accessed by READ_ONCE_NOCHECK(). The KernelThreadSanitizer
(KTSAN) is going to ignore it as well.
This patch creates __read_once_size_nocheck() a clone of
__read_once_size(). The only difference between them is
'no_sanitized_address' attribute appended to '*_nocheck'
function. This attribute tells the compiler that instrumentation
of memory accesses should not be applied to that function. We
declare it as static '__maybe_unsed' because GCC is not capable
to inline such function:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67368
With KASAN=n READ_ONCE_NOCHECK() is just a clone of READ_ONCE().
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Kostya Serebryany <kcc@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wolfram Gloger <wmglo@dent.med.uni-muenchen.de>
Cc: kasan-dev <kasan-dev@googlegroups.com>
Link: http://lkml.kernel.org/r/1445243838-17763-2-git-send-email-aryabinin@virtuozzo.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
sparse does not understand the s390 specific hotpatch attribute and
floods the log with messages like
include/uapi/linux/swab.h:92:8: error: attribute 'hotpatch': unknown attribute
Let's just dont use it, if __CHECKER__ is defined.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The kernel build bot showed a new warning triggered by commit:
76695af20c ("locking, arch: use WRITE_ONCE()/READ_ONCE() in smp_store_release()/smp_load_acquire()")
because Sparse does not like WRITE_ONCE() accessing elements
from the (sparse) RCU address space:
fs/afs/inode.c:448:9: sparse: incorrect type in initializer (different address spaces)
fs/afs/inode.c:448:9: expected struct afs_permits *__val
fs/afs/inode.c:448:9: got void [noderef] <asn:4>*<noident>
Solution is to force cast away the sparse attributes for the initializer
of the union in WRITE_ONCE().
(And as this now gets too long, also split the macro into multiple lines.)
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1438674948-38310-2-git-send-email-borntraeger@de.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull libnvdimm fixes from Dan Williams:
"1) Fixes for a handful of smatch reports (Thanks Dan C.!) and minor
bug fixes (patches 1-6)
2) Correctness fixes to the BLK-mode nvdimm driver (patches 7-10).
Granted these are slightly large for a -rc update. They have been
out for review in one form or another since the end of May and were
deferred from the merge window while we settled on the "PMEM API"
for the PMEM-mode nvdimm driver (ie memremap_pmem, memcpy_to_pmem,
and wmb_pmem).
Now that those apis are merged we implement them in the BLK driver
to guarantee that mmio aperture moves stay ordered with respect to
incoming read/write requests, and that writes are flushed through
those mmio-windows and platform-buffers to be persistent on media.
These pass the sub-system unit tests with the updates to
tools/testing/nvdimm, and have received a successful build-report from
the kbuild robot (468 configs).
With acks from Rafael for the touches to drivers/acpi/"
* 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/nvdimm:
nfit: add support for NVDIMM "latch" flag
nfit: update block I/O path to use PMEM API
tools/testing/nvdimm: add mock acpi_nfit_flush_address entries to nfit_test
tools/testing/nvdimm: fix return code for unimplemented commands
tools/testing/nvdimm: mock ioremap_wt
pmem: add maintainer for include/linux/pmem.h
nfit: fix smatch "use after null check" report
nvdimm: Fix return value of nvdimm_bus_init() if class_create() fails
libnvdimm: smatch cleanups in __nd_ioctl
sparse: fix misplaced __pmem definition
Main excitement here is Peter Zijlstra's lockless rbtree optimization to
speed module address lookup. He found some abusers of the module lock
doing that too.
A little bit of parameter work here too; including Dan Streetman's breaking
up the big param mutex so writing a parameter can load another module (yeah,
really). Unfortunately that broke the usual suspects, !CONFIG_MODULES and
!CONFIG_SYSFS, so those fixes were appended too.
Cheers,
Rusty.
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Merge tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux
Pull module updates from Rusty Russell:
"Main excitement here is Peter Zijlstra's lockless rbtree optimization
to speed module address lookup. He found some abusers of the module
lock doing that too.
A little bit of parameter work here too; including Dan Streetman's
breaking up the big param mutex so writing a parameter can load
another module (yeah, really). Unfortunately that broke the usual
suspects, !CONFIG_MODULES and !CONFIG_SYSFS, so those fixes were
appended too"
* tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (26 commits)
modules: only use mod->param_lock if CONFIG_MODULES
param: fix module param locks when !CONFIG_SYSFS.
rcu: merge fix for Convert ACCESS_ONCE() to READ_ONCE() and WRITE_ONCE()
module: add per-module param_lock
module: make perm const
params: suppress unused variable error, warn once just in case code changes.
modules: clarify CONFIG_MODULE_COMPRESS help, suggest 'N'.
kernel/module.c: avoid ifdefs for sig_enforce declaration
kernel/workqueue.c: remove ifdefs over wq_power_efficient
kernel/params.c: export param_ops_bool_enable_only
kernel/params.c: generalize bool_enable_only
kernel/module.c: use generic module param operaters for sig_enforce
kernel/params: constify struct kernel_param_ops uses
sysfs: tightened sysfs permission checks
module: Rework module_addr_{min,max}
module: Use __module_address() for module_address_lookup()
module: Make the mod_tree stuff conditional on PERF_EVENTS || TRACING
module: Optimize __module_address() using a latched RB-tree
rbtree: Implement generic latch_tree
seqlock: Introduce raw_read_seqcount_latch()
...
Move the definition of __pmem outside of CONFIG_SPARSE_RCU_POINTER to fix:
drivers/nvdimm/pmem.c:198:17: sparse: too many arguments for function __builtin_expect
drivers/nvdimm/pmem.c:36:33: sparse: expected ; at end of declaration
drivers/nvdimm/pmem.c:48:21: sparse: void declaration
...due to __pmem failing to be defined in some configurations when
CONFIG_SPARSE_RCU_POINTER=y.
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
4 drivers / enabling modules:
NFIT:
Instantiates an "nvdimm bus" with the core and registers memory devices
(NVDIMMs) enumerated by the ACPI 6.0 NFIT (NVDIMM Firmware Interface
table). After registering NVDIMMs the NFIT driver then registers
"region" devices. A libnvdimm-region defines an access mode and the
boundaries of persistent memory media. A region may span multiple
NVDIMMs that are interleaved by the hardware memory controller. In
turn, a libnvdimm-region can be carved into a "namespace" device and
bound to the PMEM or BLK driver which will attach a Linux block device
(disk) interface to the memory.
PMEM:
Initially merged in v4.1 this driver for contiguous spans of persistent
memory address ranges is re-worked to drive PMEM-namespaces emitted by
the libnvdimm-core. In this update the PMEM driver, on x86, gains the
ability to assert that writes to persistent memory have been flushed all
the way through the caches and buffers in the platform to persistent
media. See memcpy_to_pmem() and wmb_pmem().
BLK:
This new driver enables access to persistent memory media through "Block
Data Windows" as defined by the NFIT. The primary difference of this
driver to PMEM is that only a small window of persistent memory is
mapped into system address space at any given point in time. Per-NVDIMM
windows are reprogrammed at run time, per-I/O, to access different
portions of the media. BLK-mode, by definition, does not support DAX.
BTT:
This is a library, optionally consumed by either PMEM or BLK, that
converts a byte-accessible namespace into a disk with atomic sector
update semantics (prevents sector tearing on crash or power loss). The
sinister aspect of sector tearing is that most applications do not know
they have a atomic sector dependency. At least today's disk's rarely
ever tear sectors and if they do one almost certainly gets a CRC error
on access. NVDIMMs will always tear and always silently. Until an
application is audited to be robust in the presence of sector-tearing
the usage of BTT is recommended.
Thanks to: Ross Zwisler, Jeff Moyer, Vishal Verma, Christoph Hellwig,
Ingo Molnar, Neil Brown, Boaz Harrosh, Robert Elliott, Matthew Wilcox,
Andy Rudoff, Linda Knippers, Toshi Kani, Nicholas Moulin, Rafael
Wysocki, and Bob Moore.
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Merge tag 'libnvdimm-for-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/nvdimm
Pull libnvdimm subsystem from Dan Williams:
"The libnvdimm sub-system introduces, in addition to the
libnvdimm-core, 4 drivers / enabling modules:
NFIT:
Instantiates an "nvdimm bus" with the core and registers memory
devices (NVDIMMs) enumerated by the ACPI 6.0 NFIT (NVDIMM Firmware
Interface table).
After registering NVDIMMs the NFIT driver then registers "region"
devices. A libnvdimm-region defines an access mode and the
boundaries of persistent memory media. A region may span multiple
NVDIMMs that are interleaved by the hardware memory controller. In
turn, a libnvdimm-region can be carved into a "namespace" device and
bound to the PMEM or BLK driver which will attach a Linux block
device (disk) interface to the memory.
PMEM:
Initially merged in v4.1 this driver for contiguous spans of
persistent memory address ranges is re-worked to drive
PMEM-namespaces emitted by the libnvdimm-core.
In this update the PMEM driver, on x86, gains the ability to assert
that writes to persistent memory have been flushed all the way
through the caches and buffers in the platform to persistent media.
See memcpy_to_pmem() and wmb_pmem().
BLK:
This new driver enables access to persistent memory media through
"Block Data Windows" as defined by the NFIT. The primary difference
of this driver to PMEM is that only a small window of persistent
memory is mapped into system address space at any given point in
time.
Per-NVDIMM windows are reprogrammed at run time, per-I/O, to access
different portions of the media. BLK-mode, by definition, does not
support DAX.
BTT:
This is a library, optionally consumed by either PMEM or BLK, that
converts a byte-accessible namespace into a disk with atomic sector
update semantics (prevents sector tearing on crash or power loss).
The sinister aspect of sector tearing is that most applications do
not know they have a atomic sector dependency. At least today's
disk's rarely ever tear sectors and if they do one almost certainly
gets a CRC error on access. NVDIMMs will always tear and always
silently. Until an application is audited to be robust in the
presence of sector-tearing the usage of BTT is recommended.
Thanks to: Ross Zwisler, Jeff Moyer, Vishal Verma, Christoph Hellwig,
Ingo Molnar, Neil Brown, Boaz Harrosh, Robert Elliott, Matthew Wilcox,
Andy Rudoff, Linda Knippers, Toshi Kani, Nicholas Moulin, Rafael
Wysocki, and Bob Moore"
* tag 'libnvdimm-for-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/nvdimm: (33 commits)
arch, x86: pmem api for ensuring durability of persistent memory updates
libnvdimm: Add sysfs numa_node to NVDIMM devices
libnvdimm: Set numa_node to NVDIMM devices
acpi: Add acpi_map_pxm_to_online_node()
libnvdimm, nfit: handle unarmed dimms, mark namespaces read-only
pmem: flag pmem block devices as non-rotational
libnvdimm: enable iostat
pmem: make_request cleanups
libnvdimm, pmem: fix up max_hw_sectors
libnvdimm, blk: add support for blk integrity
libnvdimm, btt: add support for blk integrity
fs/block_dev.c: skip rw_page if bdev has integrity
libnvdimm: Non-Volatile Devices
tools/testing/nvdimm: libnvdimm unit test infrastructure
libnvdimm, nfit, nd_blk: driver for BLK-mode access persistent memory
nd_btt: atomic sector updates
libnvdimm: infrastructure for btt devices
libnvdimm: write blk label set
libnvdimm: write pmem label set
libnvdimm: blk labels and namespace instantiation
...
Based on an original patch by Ross Zwisler [1].
Writes to persistent memory have the potential to be posted to cpu
cache, cpu write buffers, and platform write buffers (memory controller)
before being committed to persistent media. Provide apis,
memcpy_to_pmem(), wmb_pmem(), and memremap_pmem(), to write data to
pmem and assert that it is durable in PMEM (a persistent linear address
range). A '__pmem' attribute is added so sparse can track proper usage
of pointers to pmem.
This continues the status quo of pmem being x86 only for 4.2, but
reworks to ioremap, and wider implementation of memremap() will enable
other archs in 4.3.
[1]: https://lists.01.org/pipermail/linux-nvdimm/2015-May/000932.html
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
[djbw: various reworks]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
This mirrors the change introduced by 7d0ae8086b of same title
in Linus' tree; it's not obvious as a merge resolution since we moved
the function.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Pull locking updates from Ingo Molnar:
"The main changes are:
- 'qspinlock' support, enabled on x86: queued spinlocks - these are
now the spinlock variant used by x86 as they outperform ticket
spinlocks in every category. (Waiman Long)
- 'pvqspinlock' support on x86: paravirtualized variant of queued
spinlocks. (Waiman Long, Peter Zijlstra)
- 'qrwlock' support, enabled on x86: queued rwlocks. Similar to
queued spinlocks, they are now the variant used by x86:
CONFIG_ARCH_USE_QUEUED_SPINLOCKS=y
CONFIG_QUEUED_SPINLOCKS=y
CONFIG_ARCH_USE_QUEUED_RWLOCKS=y
CONFIG_QUEUED_RWLOCKS=y
- various lockdep fixlets
- various locking primitives cleanups, further WRITE_ONCE()
propagation"
* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits)
locking/lockdep: Remove hard coded array size dependency
locking/qrwlock: Don't contend with readers when setting _QW_WAITING
lockdep: Do not break user-visible string
locking/arch: Rename set_mb() to smp_store_mb()
locking/arch: Add WRITE_ONCE() to set_mb()
rtmutex: Warn if trylock is called from hard/softirq context
arch: Remove __ARCH_HAVE_CMPXCHG
locking/rtmutex: Drop usage of __HAVE_ARCH_CMPXCHG
locking/qrwlock: Rename QUEUE_RWLOCK to QUEUED_RWLOCKS
locking/pvqspinlock: Rename QUEUED_SPINLOCK to QUEUED_SPINLOCKS
locking/pvqspinlock: Replace xchg() by the more descriptive set_mb()
locking/pvqspinlock, x86: Enable PV qspinlock for Xen
locking/pvqspinlock, x86: Enable PV qspinlock for KVM
locking/pvqspinlock, x86: Implement the paravirt qspinlock call patching
locking/pvqspinlock: Implement simple paravirt support for the qspinlock
locking/qspinlock: Revert to test-and-set on hypervisors
locking/qspinlock: Use a simple write to grab the lock
locking/qspinlock: Optimize for smaller NR_CPUS
locking/qspinlock: Extract out code snippets for the next patch
locking/qspinlock: Add pending bit
...
I want to use lockless_dereference() from seqlock.h, which would mean
including rcupdate.h from it, however rcupdate.h already includes
seqlock.h.
Avoid this by moving lockless_dereference() into compiler.h. This is
somewhat tricky since it uses smp_read_barrier_depends() which isn't
available there, but its a CPP macro so we can get away with it.
The alternative would be moving it into asm/barrier.h, but that would
be updating each arch (I can do if people feel that is more
appropriate).
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
The current formulation of control dependencies fails on DEC Alpha,
which does not respect dependencies of any kind unless an explicit
memory barrier is provided. This means that the current fomulation of
control dependencies fails on Alpha. This commit therefore creates a
READ_ONCE_CTRL() that has the same overhead on non-Alpha systems, but
causes Alpha to produce the needed ordering. This commit also applies
READ_ONCE_CTRL() to the one known use of control dependencies.
Use of READ_ONCE_CTRL() also has the beneficial effect of adding a bit
of self-documentation to control dependencies.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Since we assume set_mb() to result in a single store followed by a
full memory barrier, employ WRITE_ONCE().
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Looks like commit :
43239cbe79 ("kernel: Change ASSIGN_ONCE(val, x) to WRITE_ONCE(x, val)")
left behind a reference to ASSIGN_ONCE(). Update this to WRITE_ONCE().
Signed-off-by: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: borntraeger@de.ibm.com
Cc: dave@stgolabs.net
Cc: paulmck@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/20150430115721.22278.94082.stgit@preeti.in.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
In commit 0b053c9518 ("lib: memzero_explicit: use barrier instead
of OPTIMIZER_HIDE_VAR"), we made memzero_explicit() more robust in
case LTO would decide to inline memzero_explicit() and eventually
find out it could be elimiated as dead store.
While using barrier() works well for the case of gcc, recent efforts
from LLVMLinux people suggest to use llvm as an alternative to gcc,
and there, Stephan found in a simple stand-alone user space example
that llvm could nevertheless optimize and thus elimitate the memset().
A similar issue has been observed in the referenced llvm bug report,
which is regarded as not-a-bug.
Based on some experiments, icc is a bit special on its own, while it
doesn't seem to eliminate the memset(), it could do so with an own
implementation, and then result in similar findings as with llvm.
The fix in this patch now works for all three compilers (also tested
with more aggressive optimization levels). Arguably, in the current
kernel tree it's more of a theoretical issue, but imho, it's better
to be pedantic about it.
It's clearly visible with gcc/llvm though, with the below code: if we
would have used barrier() only here, llvm would have omitted clearing,
not so with barrier_data() variant:
static inline void memzero_explicit(void *s, size_t count)
{
memset(s, 0, count);
barrier_data(s);
}
int main(void)
{
char buff[20];
memzero_explicit(buff, sizeof(buff));
return 0;
}
$ gcc -O2 test.c
$ gdb a.out
(gdb) disassemble main
Dump of assembler code for function main:
0x0000000000400400 <+0>: lea -0x28(%rsp),%rax
0x0000000000400405 <+5>: movq $0x0,-0x28(%rsp)
0x000000000040040e <+14>: movq $0x0,-0x20(%rsp)
0x0000000000400417 <+23>: movl $0x0,-0x18(%rsp)
0x000000000040041f <+31>: xor %eax,%eax
0x0000000000400421 <+33>: retq
End of assembler dump.
$ clang -O2 test.c
$ gdb a.out
(gdb) disassemble main
Dump of assembler code for function main:
0x00000000004004f0 <+0>: xorps %xmm0,%xmm0
0x00000000004004f3 <+3>: movaps %xmm0,-0x18(%rsp)
0x00000000004004f8 <+8>: movl $0x0,-0x8(%rsp)
0x0000000000400500 <+16>: lea -0x18(%rsp),%rax
0x0000000000400505 <+21>: xor %eax,%eax
0x0000000000400507 <+23>: retq
End of assembler dump.
As gcc, clang, but also icc defines __GNUC__, it's sufficient to define
this in compiler-gcc.h only to be picked up. For a fallback or otherwise
unsupported compiler, we define it as a barrier. Similarly, for ecc which
does not support gcc inline asm.
Reference: https://llvm.org/bugs/show_bug.cgi?id=15495
Reported-by: Stephan Mueller <smueller@chronox.de>
Tested-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Stephan Mueller <smueller@chronox.de>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: mancha security <mancha1@zoho.com>
Cc: Mark Charlebois <charlebm@gmail.com>
Cc: Behan Webster <behanw@converseincode.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The fact that volatile allows for atomic load/stores is a special case
not a requirement for {READ,WRITE}_ONCE(). Their primary purpose is to
force the compiler to emit load/stores _once_.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
