Objtool is failing to build with GCC 4.4.7 due to the following
warnings:
cc1: warnings being treated as errors
In file included from orc.h:21,
from orc_gen.c:21:
orc_types.h:86: error: packed attribute is unnecessary for ‘sp_offset’
orc_types.h:87: error: packed attribute is unnecessary for ‘bp_offset’
orc_types.h:88: error: packed attribute is unnecessary for ‘sp_reg’
I suspect those warnings are a GCC bug. But -Wpacked isn't very useful
anyway, so just disable it.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 627fce1480 ("objtool: Add ORC unwind table generation")
Link: http://lkml.kernel.org/r/76d85d7b5a87566465095c500bce222ff5d7b146.1501188854.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Arnd reported some false positive warnings with GCC 7:
drivers/hid/wacom_wac.o: warning: objtool: wacom_bpt3_touch()+0x2a5: stack state mismatch: cfa1=7+8 cfa2=6+16
drivers/iio/adc/vf610_adc.o: warning: objtool: vf610_adc_calculate_rates() falls through to next function vf610_adc_sample_set()
drivers/pwm/pwm-hibvt.o: warning: objtool: hibvt_pwm_get_state() falls through to next function hibvt_pwm_remove()
drivers/pwm/pwm-mediatek.o: warning: objtool: mtk_pwm_config() falls through to next function mtk_pwm_enable()
drivers/spi/spi-bcm2835.o: warning: objtool: .text: unexpected end of section
drivers/spi/spi-bcm2835aux.o: warning: objtool: .text: unexpected end of section
drivers/watchdog/digicolor_wdt.o: warning: objtool: dc_wdt_get_timeleft() falls through to next function dc_wdt_restart()
When GCC 7 detects a potential divide-by-zero condition, it sometimes
inserts a UD2 instruction for the case where the divisor is zero,
instead of letting the hardware trap on the divide instruction.
Objtool doesn't consider UD2 to be fatal unless it's annotated with
unreachable(). So it considers the GCC-generated UD2 to be non-fatal,
and it tries to follow the control flow past the UD2 and gets
confused.
Previously, objtool *did* assume UD2 was always a dead end. That
changed with the following commit:
d1091c7fa3 ("objtool: Improve detection of BUG() and other dead ends")
The motivation behind that change was that Peter was planning on using
UD2 for __WARN(), which is *not* a dead end. However, it turns out
that some emulators rely on UD2 being fatal, so he ended up using
'ud0' instead:
9a93848fe7 ("x86/debug: Implement __WARN() using UD0")
For GCC 4.5+, it should be safe to go back to the previous assumption
that UD2 is fatal, even when it's not annotated with unreachable().
But for pre-4.5 versions of GCC, the unreachable() macro isn't
supported, so such cases of UD2 need to be explicitly annotated as
reachable.
Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: d1091c7fa3 ("objtool: Improve detection of BUG() and other dead ends")
Link: http://lkml.kernel.org/r/e57fa9dfede25f79487da8126ee9cdf7b856db65.1501188854.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Currently flush_tmregs_to_thread() does not save the TM SPRs (TFHAR,
TFIAR, TEXASR) to the thread struct, unless the process is currently
inside a suspended transaction.
If the process is core dumping, and the TM SPRs have changed since the
last time the process was context switched, then we will save stale
values of the TM SPRs to the core dump.
Fix it by saving the live register state to the thread struct in that
case.
Fixes: 08e1c01d6a ("powerpc/ptrace: Enable support for TM SPR state")
Cc: stable@vger.kernel.org # v4.8+
Signed-off-by: Gustavo Romero <gromero@linux.vnet.ibm.com>
Reviewed-by: Cyril Bur <cyrilbur@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The Radix MMU translation tree as defined in ISA v3.0 contains two
different types of entry, directories and leaves. Leaves are
identified by _PAGE_PTE being set.
The formats of the two entries are different, with the directory
entries containing no spare bits for use by software. In particular
the bit we use for _PAGE_DEVMAP is not reserved for software, and is
part of the NLB (Next Level Base) field, essentially the address of
the next level in the tree.
Note that the Linux pte_t is not == _PAGE_PTE. A huge page pmd
entry (or devmap!) is also a leaf and so has _PAGE_PTE set, even
though we use a pmd_t for it in Linux.
The fix is to ensure that the pmd/pte_devmap() confirm they are
looking at a leaf entry (_PAGE_PTE) as well as checking _PAGE_DEVMAP.
Fixes: ebd3119793 ("powerpc/mm: Add devmap support for ppc64")
Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Tested-by: Laurent Vivier <lvivier@redhat.com>
Tested-by: Jose Ricardo Ziviani <joserz@linux.vnet.ibm.com>
Reviewed-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
[mpe: Add a comment in the code and flesh out change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
dtc recently added PCI bus checks. Fix these warnings.
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
The SSI_LOG macros already add __func__ to log messages, so remove
log message that add them a second time in the log message itself.
Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This is a patch to the rtw_mlme_ext.c file that fixes up a brace error
found by the checkpatch.pl tool
Signed-off-by: Armin Schoenlieb <armetallica@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The cfg_action bit comes from the high bit of pmsg[4] so the
current mask and shift are in correct and always result in
zero. Fix this by using the correct mask and shif to get the
correct cfg_action bit value.
Detected by CoverityScan, CID#142890 ("Operands don't affect result")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fix an error detected by checkpatch.pl on line 75 and move the opening
brace after the function signature to a new line.
Signed-off-by: Munir Contractor <munircontractor@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
checkpatch.pl line over 80 characters so fix the formatting
for coding style compliance.
Signed-off-by: Deb McLemore <debmc@linux.vnet.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Unnecessary platform_set_drvdata() has been removed since the driver
core clears the driver data to NULL after device release or on
probe failure. There is no need to manually clear the device
driver data to NULL.
The Coccinelle semantic patch used to make this change is as follows:
//<smpl>
@@
struct platform_device *pdev;
@@
- platform_set_drvdata(pdev, NULL);
//</smpl>
Signed-off-by: Amitoj Kaur Chawla <amitoj1606@gmail.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
attribute_group are not supposed to change at runtime. All functions
working with attribute_group provided by <linux/sysfs.h> work
with const attribute_group. So mark the non-const structs as const.
Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Jonathan writes:
First round of IIO new device support, features and cleanups for the 4.14 cycle.
4 completely new drivers in this set and plenty of other stuff.
One ABI change due to a silly mistake a long time back. Hopefully no
one will notice. It effects the numerical order of consumer device
channels which was the reverse of the obvious. It's going the slow
way to allow us some margin to spot if we have broken userspace or
not (seems unlikely)
New Device Support
* ccs811
- new driver for the Volatile Organic Compounds (VOC) sensor.
* dln2 adc
- new driver for the ADC on this flexible usb board.
* EP93xx
- new driver for this Cirrus logic SoC ADC.
* ltc2471
- new ADC driver support the ltc2471 and ltc2473
* st_accel
- add trivial table entries to support H3LIS331DL, LIS331DL, LIS3LV02DL.
* st_gyro
- add L3GD20H support (again) having fixed the various things that were
broken in the first try. Includes devicetree binding.
* stm32 dac
- add support for the DACs in the STM32F4 series
Features
* Documentation
- add missing power attribute documentation to the ABI docs.
* at91-sama5d2
- add hardware trigger and buffered capture support with bindings.
- suspend and resume functionality.
* bmc150
- support for the BOSC0200 ACPI device id seen on some tablets.
* hdc100x
- devicetree bindings
- document supported devices
- match table and device ids.
* hts221
- support active low interrupts (with bindings)
- open drain mode with bindings.
* htu21
- OF match table and bindings.
* lsm6dsx
- open drain mode with bindings
* ltc2497
- add support for board file based consumer mapping.
* ms5367
- OF match table and bindings.
* mt7622
- binding document and OF match table.
- suspend and resume support.
* rpr0521
- triggered buffer support.
* tsys01
- OF match table and bindings.
Cleanups and minor fixes
* core
- fix ordering of IIO channels to entry numbers when using
iio_map_array_register rather than reversing them.
- use the new %pOF format specifier rather than full name for the
device tree nodes.
* ad7280a
- fix potential issue with macro argument reuse.
* ad7766
- drop a pointless NULL value check as it's done in the gpiod code.
* adis16400
- unsigned -> unsigned int.
* at91 adc
- make some init data static to reduce code size.
* at91-sama5d2 ADC
- make some init data static to reduce code size.
* da311
- make some init data static to reduce code size.
* hid-sensor-rotation
- drop an unnecessary static.
* hts221
- refactor the write_with_mask code.
- move the BDU configuration to probe time as there is no reason for it
to change.
- avoid overwriting reserved data during power-down. This is a fix, but
the infrastructure need was too invasive to send it to mainline except
in a merge window. It's not a regression as it was always wrong.
- avoid reconfigure the sampling frequency multiple times by just
doing it in the write_raw function directly.
- refactor the power_on/off calls into a set_enable.
- move the dry-enable logic into trig_set_state as that is the only
place it was used.
* ina219
- fix polling of ina226 conversion ready flag.
* imx7d
- add vendor name in kconfig for consistency with similar parts.
* mcp3422
- Change initial channel to 0 as it feels more logical.
- Check for some errors in probe.
* meson-saradc
- add a check of of_match_device return value.
* mpu3050
- allow open drain for any interrupt type.
* rockchip adc
- add check on of_match_device return value.
* sca3000
- drop a trailing whitespace.
* stm32 adc
- make array stm32h7_adc_ckmodes_spec static.
* stm32 dac
- fix an error message.
* stm32 timers
- fix clock name in docs to match reality after changes.
* st_accel
- explicit OF table (spi).
- add missing entries to OF table (i2c).
- rename of_device_id table to drop the part name.
- adding missing lis3l02dq entry to bindings.
- rename H3LIS331DL_DRIVER_NAME to line up with similar entries in driver.
* st_gyro
- explicit OF table (spi).
* st_magn
- explicit OF table (spi).
- enable multiread for lis3mdl.
* st_pressure
- explicit OF table (spi).
* st_sensors common.
- move st_sensors_of_i2c_probe and rename to make it available for spi
drivers.
* tsc3472
- don't write an extra byte when writing the ATIME register.
- add a link to the datasheet.
* tsl2x7x - continued staging cleanups
- add of_match_table.
- drop redundant power_state sysfs attribute.
- drop wrapper tsl2x7x_i2c_read.
- clean up i2c calls made in tsl2x7x_als_calibrate.
- refactor the read and write _event_value callbacks to handle additional
elements.
- use usleep_range instead of mdelay.
- check return value from tsl2x7x_invoke_change.
* zpa2326
- add some newline to the end of logging macros.
The hardware spinlock drivers now depend on HWSPINLOCK (instead of
selecting it), so we need to explicitly enable it after commit
35fc8a07d7 ("Make HWSPINLOCK a menuconfig to ease disabling")
Without HWSPINLOCK, various drivers are left with unsatisfied
dependencies and Qcom boards using shared memory based communication
to request regulators are failing to boot and mount rootfs.
Fix this by explicitly enabling HWSPINLOCK in defconfig.
Signed-off-by: Georgi Djakov <georgi.djakov@linaro.org>
Signed-off-by: Andy Gross <andy.gross@linaro.org>
Pull drm fixes from Dave Airlie:
"These iare the fixes for 4.13-rc3: vmwgfx, exynos, i915, amdgpu,
nouveau, host1x and displayport fixes.
As expected people woke up this week, i915 didn't do an -rc2 pull so
got a bumper -rc3 pull, and Ben resurfaced on nouveau and fixed a
bunch of major crashers seen on Fedora 26, and there are a few vmwgfx
fixes as well.
Otherwise exynos had some regression fixes/cleanups, and amdgpu has an
rcu locking regression fix and a couple of minor fixes"
* tag 'drm-fixes-for-v4.13-rc3' of git://people.freedesktop.org/~airlied/linux: (44 commits)
drm/i915: Fix bad comparison in skl_compute_plane_wm.
drm/i915: Force CPU synchronisation even if userspace requests ASYNC
drm/i915: Only skip updating execobject.offset after error
drm/i915: Only mark the execobject as pinned on success
drm/i915: Remove assertion from raw __i915_vma_unpin()
drm/i915/cnl: Fix loadgen select programming on ddi vswing sequence
drm/i915: Fix scaler init during CRTC HW state readout
drm/i915/selftests: Fix an error handling path in 'mock_gem_device()'
drm/i915: Unbreak gpu reset vs. modeset locking
gpu: host1x: Free the IOMMU domain when there is no device to attach
drm/i915: Fix cursor updates on some platforms
drm/i915: Fix user ptr check size in eb_relocate_vma()
drm: exynos: mark pm functions as __maybe_unused
drm/exynos: select CEC_CORE if CEC_NOTIFIER
drm/exynos/hdmi: fix disable sequence
drm/exynos: mic: add a bridge at probe
drm/exynos/dsi: Remove error handling for bridge_node DT parsing
drm/exynos: dsi: do not try to find bridge
drm: exynos: hdmi: make of_device_ids const.
drm: exynos: constify mixer_match_types and *_mxr_drv_data.
...
Summary:
- fix probing fail issue of dsi driver without bridge device.
- fix disable sequence of hdmi driver.
- trivial cleanups.
* tag 'exynos-drm-fixes-for-v4.13-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/daeinki/drm-exynos:
drm: exynos: mark pm functions as __maybe_unused
drm/exynos: select CEC_CORE if CEC_NOTIFIER
drm/exynos/hdmi: fix disable sequence
drm/exynos: mic: add a bridge at probe
drm/exynos/dsi: Remove error handling for bridge_node DT parsing
drm/exynos: dsi: do not try to find bridge
drm: exynos: hdmi: make of_device_ids const.
drm: exynos: constify mixer_match_types and *_mxr_drv_data.
exynos_drm: Clean up duplicated assignment in exynos_drm_driver
Rick Farrington says:
====================
liquidio: standardization and cleanup
This patchset corrects some non-standard macro usage.
1. Replaced custom MIN macro with use of standard 'min_t'.
2. Removed cryptic and misleading macro 'CAST_ULL'.
change log:
V1 -> V2:
1. Add driver cleanup of macro 'CAST_ULL'.
V2 -> V3:
1. Remove extra parentheses from previous usage of macro 'CAST_ULL'.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Since commit a390d1f379 ("phylib: convert state_queue work to
delayed_work"), the PHYLIB state machine was converted to use delayed
workqueues, yet some functions were still referencing the PHY library
timer in their comments, fix that and remove the now unused
linux/timer.h include.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Jakub Kicinski says:
====================
nfp: extend firmware request logic
We have been pondering for some time how to support loading different
application firmwares onto NFP. We want to support both users selecting
one of the firmware images provided by Netronome (which are optimized
for different use cases each) as well as firmware images created by
users themselves or other companies.
In the end we decided to go with the simplest solution - depending on
the right firmware image being placed in /lib/firmware. This vastly
simplifies driver logic and also doesn't require any new API.
Different NICs on one system may want to run different applications
therefore we first try to load firmware specific to the device (by
serial number of PCI slot) and if not present try the device model
based name we have been using so far.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
request_firmware() will fallback to user space helper and may cause
long delays when driver is loaded if udev doesn't correctly handle
FW requests. Since we never really made use of the user space
helper functionality switch to the simpler request_firmware_direct()
call. The side effect of this change is that no warning will be
printed when the FW image does not exists. To help users figure
out which FW file is missing print a info message when we request
each file.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We generally look up firmware by card type, but that doesn't allow
users who have more than one card of the same type in their system
to select firmware per adapter.
Unfortunately user space firmware helper seems fraught with
difficulties and to be on its way out. In particular support for
handling firmware uevents have been dropped from systemd and most
distributions don't enable the FW fallback by default any more.
To allow users selecting firmware for a particular device look up
firmware names by serial and pci_name(). Use the direct lookup to
disable generating uevents when enabled in Kconfig and not print
any warnings to logs if adapter-specific files are missing. Users
can place in /lib/firmware/netronome files named:
pci-${pci_name}.nffw
serial-${serial}.nffw
to target a specific card. E.g.:
pci-0000:04:00.0.nffw
pci-0000:82:00.0.nffw
serial-00-aa-bb-11-22-33-10-ff.nffw
We use the full serial number including the interface id, as it
appears in lspci output (bytes separated by '-').
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We use a hack to defer probe when firmware was not pre-loaded
or found on disk. This helps in case users forgot to include
firmware in initramfs, the driver will most likely get another
shot at probing after real root is mounted.
This is not for what EPROBE_DEFER is supposed to be used, and
when FW is completely missing every time new device is probed
NFP will reprobe spamming kernel logs.
Remove this hack, users will now have to make sure the right
firmware image is present in initramfs if nfp.ko is placed
there or built in.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The driver attempts to 'select MDIO_DEVICE', but the code
is actually a loadable module when PHYLIB=m:
drivers/phy/broadcom/phy-bcm-ns-usb3.o: In function `bcm_ns_usb3_mdiodev_phy_write':
phy-bcm-ns-usb3.c:(.text.bcm_ns_usb3_mdiodev_phy_write+0x28): undefined reference to `mdiobus_write'
drivers/phy/broadcom/phy-bcm-ns-usb3.o: In function `bcm_ns_usb3_module_exit':
phy-bcm-ns-usb3.c:(.exit.text+0x18): undefined reference to `mdio_driver_unregister'
drivers/phy/broadcom/phy-bcm-ns-usb3.o: In function `bcm_ns_usb3_module_init':
phy-bcm-ns-usb3.c:(.init.text+0x18): undefined reference to `mdio_driver_register'
phy-bcm-ns-usb3.c:(.init.text+0x38): undefined reference to `mdio_driver_unregister'
Using 'depends on MDIO_BUS' instead will avoid the link error.
Fixes: af850e14a7 ("phy: bcm-ns-usb3: add MDIO driver using proper bus layer")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
I still see build errors in randconfig builds and have had this
patch for a while to locally work around it:
drivers/built-in.o: In function `xgene_mdio_probe':
mux-core.c:(.text+0x352154): undefined reference to `of_mdiobus_register'
mux-core.c:(.text+0x352168): undefined reference to `mdiobus_free'
mux-core.c:(.text+0x3521c0): undefined reference to `mdiobus_alloc_size'
The idea is that CONFIG_MDIO_BUS now reflects whether the mdio_bus
code is built-in or a module, and other drivers that use the core
code can simply depend on that, instead of having a complex
dependency line.
Fixes: 90eff9096c ("net: phy: Allow splitting MDIO bus/device support from PHYs")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
i915 fixes for -rc3
Bit more than usual since we missed -rc2. 4x cc: stable, 2 gvt
patches, but all fairly minor stuff. Last minute rebase was to add a
few missing cc: stable, I did prep the pull this morning already and
made sure CI approves.
* tag 'drm-intel-fixes-2017-07-27' of git://anongit.freedesktop.org/git/drm-intel:
drm/i915: Fix bad comparison in skl_compute_plane_wm.
drm/i915: Force CPU synchronisation even if userspace requests ASYNC
drm/i915: Only skip updating execobject.offset after error
drm/i915: Only mark the execobject as pinned on success
drm/i915: Remove assertion from raw __i915_vma_unpin()
drm/i915/cnl: Fix loadgen select programming on ddi vswing sequence
drm/i915: Fix scaler init during CRTC HW state readout
drm/i915/selftests: Fix an error handling path in 'mock_gem_device()'
drm/i915: Unbreak gpu reset vs. modeset locking
drm/i915: Fix cursor updates on some platforms
drm/i915: Fix user ptr check size in eb_relocate_vma()
drm/i915/gvt: Extend KBL platform support in GVT-g
drm/i915/gvt: Fix the vblank timer close issue after shutdown VMs in reverse
Core Changes:
- dp: A few fixes in drm_dp_downstream_debug() (Chris)
- rockchip: sanitize the Kconfig dependencies (fallout from EXTCON) (Arnd)
- host1x: Free the iommu domain when attach_device fails (Paul)
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Paul Kocialkowski <contact@paulk.fr>
* tag 'drm-misc-fixes-2017-07-27' of git://anongit.freedesktop.org/git/drm-misc:
gpu: host1x: Free the IOMMU domain when there is no device to attach
drm/rockchip: fix Kconfig dependencies
drm/dp: Don't trust drm_dp_downstream_id()
drm/dp: Fix read pointer for drm_dp_downsteam_debug()
This enables the creation of ADC platform device on EDB93xx series of Cirrus
Logic evaluation boards. The driver for this device must be enabled separately,
either as built-in, or a module.
Signed-off-by: Alexander Sverdlin <alexander.sverdlin@gmail.com>
Newly provided ep93xx_register_adc() could be used by machine-specific code
to create ADC platform device on Cirrus Logic EP93xx SoC-based machines.
Signed-off-by: Alexander Sverdlin <alexander.sverdlin@gmail.com>
ADC and keypad controller clocks share the same control register, so use the
existing infrastructure to add ADC clock support for Cirrus Logic EP93xx SoCs.
Signed-off-by: Alexander Sverdlin <alexander.sverdlin@gmail.com>
Tree RCU guarantees that every online CPU has a memory barrier between
any given grace period and any of that CPU's RCU read-side sections that
must be ordered against that grace period. Since RCU doesn't always
know where read-side critical sections are, the actual implementation
guarantees order against prior and subsequent non-idle non-offline code,
whether in an RCU read-side critical section or not. As a result, there
does not need to be a memory barrier at the end of synchronize_rcu()
and friends because the ordering internal to the grace period has
ordered every CPU's post-grace-period execution against each CPU's
pre-grace-period execution, again for all non-idle online CPUs.
In contrast, SRCU can have non-idle online CPUs that are completely
uninvolved in a given SRCU grace period, for example, a CPU that
never runs any SRCU read-side critical sections and took no part in
the grace-period processing. It is in theory possible for a given
synchronize_srcu()'s wakeup to be delivered to a CPU that was completely
uninvolved in the prior SRCU grace period, which could mean that the
code following that synchronize_srcu() would end up being unordered with
respect to both the grace period and any pre-existing SRCU read-side
critical sections.
This commit therefore adds an smp_mb() to the end of __synchronize_srcu(),
which prevents this scenario from occurring.
Reported-by: Lance Roy <ldr709@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Lance Roy <ldr709@gmail.com>
Cc: <stable@vger.kernel.org> # 4.12.x
Pull ACPI fixes from Rafael Wysocki:
"These are two fixups for the suspend-to-idle handling in the ACPI
subsystem after recent changes in that area and two simple fixes of
the ACPI NUMA code.
Specifics:
- Add an ACPI module parameter to allow users to override the new
default behavior on some systems where the EC GPE is not disabled
during suspend-to-idle in case the EC on their systems generates
excessive wakeup events and they want to sacrifice some
functionality (like power button wakeups) for extra battery life
while suspended (Rafael Wysocki).
- Fix flushing of the outstanding EC work in the ACPI core
suspend-to-idle code (Rafael Wysocki).
- Add a missing include and fix a messed-up comment in the ACPI NUMA
code (Ross Zwisler)"
* tag 'acpi-4.13-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
ACPI: NUMA: Fix typo in the full name of SRAT
ACPI: NUMA: add missing include in acpi_numa.h
ACPI / PM / EC: Flush all EC work in acpi_freeze_sync()
ACPI / EC: Add parameter to force disable the GPE on suspend
Since commit a8636c8964 (PM / Runtime: Don't allow to suspend a
device with an active child) it is no longer permitted to set
RPM_SUSPENDED state for a device with active children unless
power.ignore_children is set.
Update the documentation to reflect this.
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Add a description of the cpuinfo_cur_freq policy attribute in sysfs
to the cpufreq documentation under Documentation/admin-guide/pm/ as
it is missing after commit 2a0e492798 (cpufreq: User/admin
documentation update and consolidation) that overlooked it.
Fixes: 2a0e492798 (cpufreq: User/admin documentation update and consolidation)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
The ->get callback in the intel_pstate structure was mostly there
for the scaling_cur_freq sysfs attribute to work, but after commit
f8475cef90 (x86: use common aperfmperf_khz_on_cpu() to calculate
KHz using APERF/MPERF) that attribute uses arch_freq_get_on_cpu()
provided by the x86 arch code on all processors supported by
intel_pstate, so it doesn't need the ->get callback from the
driver any more.
Moreover, the very presence of the ->get callback in the intel_pstate
structure causes the cpuinfo_cur_freq attribute to be present when
intel_pstate operates in the active mode, which is bogus, because
the role of that attribute is to return the current CPU frequency
as seen by the hardware. For intel_pstate, though, this is just an
average frequency and not really current, but computed for the
previous sampling interval (the actual current frequency may be
way different at the point this value is obtained by reading from
cpuinfo_cur_freq), and after commit 82b4e03e01 (intel_pstate: skip
scheduler hook when in "performance" mode) the value in
cpuinfo_cur_freq may be stale or just 0, depending on the driver's
operation mode. In fact, however, on the hardware supported by
intel_pstate there is no way to read the current CPU frequency
from it, so the cpuinfo_cur_freq attribute should not be present
at all when this driver is in use.
For this reason, drop intel_pstate_get() and clear the ->get
callback pointer pointing to it, so that the cpuinfo_cur_freq is
not present for intel_pstate in the active mode any more.
Fixes: 82b4e03e01 (intel_pstate: skip scheduler hook when in "performance" mode)
Reported-by: Huaisheng Ye <yehs1@lenovo.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
* acpi-pm:
ACPI / PM / EC: Flush all EC work in acpi_freeze_sync()
ACPI / EC: Add parameter to force disable the GPE on suspend
* acpi-numa:
ACPI: NUMA: Fix typo in the full name of SRAT
ACPI: NUMA: add missing include in acpi_numa.h
