Byte count is more helpful to know than vector count.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
nfsd-1915 [003] 77915.780959: write_opened:
[FAILED TO PARSE] xid=3286130958 fh=0 offset=154624 len=1
nfsd-1915 [003] 77915.780960: write_io_done:
[FAILED TO PARSE] xid=3286130958 fh=0 offset=154624 len=1
nfsd-1915 [003] 77915.780964: write_done:
[FAILED TO PARSE] xid=3286130958 fh=0 offset=154624 len=1
Byte swapping and knfsd_fh_hash() are not available in "trace-cmd
report", where the print format string is actually used. These
data transformations have to be done during the TP_fast_assign step.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Record the time between when a rqstp is enqueued on a transport
and when it is dequeued. This includes how long the rqstp waits on
the queue and how long it takes the kernel scheduler to wake a
nfsd thread to service it.
The svc_xprt_dequeue trace point is altered to include the number
of microseconds between xprt_enqueue and xprt_dequeue.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Introduce a mechanism to report the server-side execution latency of
each RPC. The goal is to enable user space to filter the trace
record for latency outliers, build histograms, etc.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Currently, trace_svc_process has two call sites:
1. Just after a call to svc_send. svc_send already invokes
trace_svc_send with the same arguments just before returning
2. Just before a call to svc_drop. svc_drop already invokes
trace_svc_drop with the same arguments just after it is called
Therefore trace_svc_process does not provide any additional
information not already provided by these other trace points.
However, it would be useful to record the incoming RPC procedure.
So reuse trace_svc_process for this purpose.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
TP_printk defines a format string that is passed to user space for
converting raw trace event records to something human-readable.
My user space's printf (Oracle Linux 7), however, does not have a
%pI format specifier. The result is that what is supposed to be an
IP address in the output of "trace-cmd report" is just a string that
says the field couldn't be displayed.
To fix this, adopt the same approach as the client: maintain a pre-
formated presentation address for occasions when %pI is not
available.
The location of the trace_svc_send trace point is adjusted so that
rqst->rq_xprt is not NULL when the trace event is recorded.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
There doesn't seem to be a lot of value in calling trace_svc_recv
in the failing case.
1. There are two very common cases: one is the transport is not
ready, and the other is shutdown. Neither is terribly interesting.
2. The trace record for the failing case contains nothing but
the status code.
Therefore the trace point call site in the error exit is removed.
Since the trace point is now recording a length instead of a
status, rename the status field and remove the case that records a
zero XID.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
There are three cases where svc_xprt_do_enqueue() returns without
waking an nfsd thread:
1. There is no work to do
2. The transport is already busy
3. There are no available nfsd threads
Only 3. is truly interesting. Move the trace point so it records
that there was work to do and either an nfsd thread was awoken, or
a free one could not found.
As an additional clean up, remove a redundant comment and a couple
of dprintk call sites.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Reduce the amount of noise generated by trace_svc_xprt_dequeue by
moving it to the end of svc_get_next_xprt. This generates exactly
one trace event when a ready xprt is found, rather than spurious
events when there is no work to do. The empty events contain no
information that can't be obtained simply by tracing function calls
to svc_xprt_dequeue.
A small additional benefit is simplification of the svc_xprt_event
trace class, which no longer has to handle the case when the @xprt
parameter is NULL.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
XPT_KILL_TEMP was added by commit 546125d161 ("sunrpc: don't call
sleeping functions from the notifier block callbacks"), and
XPT_CONG_CTRL was added by commit 362142b258 ("sunrpc: flag
transports as having congestion control") .
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Clean up: Instead of returning a value that is used to set or clear
a bit, just make ->xpo_secure_port mangle that bit, and return void.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Clean up: Noticed during code inspection that there is already a
local automatic variable "xprt" so dereferencing rqst->rq_xprt
again is unnecessary.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Use enum nfs_cb_opnum4 in decode_cb_op_status. This fixes warnings
seen with clang:
fs/nfsd/nfs4callback.c:451:36: warning: implicit conversion from
enumeration type 'enum nfs_cb_opnum4' to different enumeration
type 'enum nfs_opnum4' [-Wenum-conversion]
status = decode_cb_op_status(xdr, OP_CB_SEQUENCE, &cb->cb_seq_status);
~~~~~~~~~~~~~~~~~~~ ^~~~~~~~~~~~~~
Signed-off-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
fs/nfsd/nfs4state.c:926:8-9: WARNING: return of 0/1 in function 'nfs4_delegation_exists' with return type bool
fs/nfsd/nfs4state.c:2955:9-10: WARNING: return of 0/1 in function 'nfsd4_compound_in_session' with return type bool
Return statements in functions returning bool should use
true/false instead of 1/0.
Generated by: scripts/coccinelle/misc/boolreturn.cocci
Fixes: 68b18f5294 ("nfsd: make nfs4_get_existing_delegation less confusing")
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
[bfields: also fix -EAGAIN]
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
A quiet release for SPI, some fixes and small updates for individual
drivers with one bigger change from Linus Walleij which coverts the
bitbanging SPI driver to use the GPIO descriptor API from Linus Walleij.
Since GPIO descriptors were used by platform data this means there's a
few changes in arch/ making relevant updates for a few platforms and one
misc driver that are affected.
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Merge tag 'spi-v4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi
Pull SPI updates from Mark Brown:
"A quiet release for SPI, some fixes and small updates for individual
drivers with one bigger change from Linus Walleij which coverts the
bitbanging SPI driver to use the GPIO descriptor API from Linus
Walleij.
Since GPIO descriptors were used by platform data this means there's a
few changes in arch/ making relevant updates for a few platforms and
one misc driver that are affected"
* tag 'spi-v4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi: (24 commits)
MAINTAINERS: update Andi's e-mail
spi: spi-atmel: Use correct enum for DMA transfer direction
spi: sh-msiof: Document R-Car M3-N support
spi: sh-msiof: Use correct enum for DMA transfer direction
spi: sprd: Add the support of restarting the system
spi: sprd: Simplify the transfer function
spi: Fix unregistration of controller with fixed SPI bus number
spi: rspi: use correct enum for DMA transfer direction
spi: jcore: disable ref_clk after getting its rate
spi: bcm-qspi: fIX some error handling paths
spi: pxa2xx: Disable runtime PM if controller registration fails
spi: tegra20-slink: use true and false for boolean values
spi: Fix scatterlist elements size in spi_map_buf
spi: atmel: init FIFOs before spi enable
spi: orion: Prepare space for per-child options
spi: orion: Make the error message greppable
spi: orion: Rework GPIO CS handling
spi: bcm2835aux: Avoid 64-bit arithmetic in xfer len calc
spi: spi-gpio: Augment device tree bindings
spi: spi-gpio: Rewrite to use GPIO descriptors
...
A very small set of updates for the regulator API this time around,
there's a few bug fixes and also:
- Conversion of the regulator API to use GPIO descriptors rather than
numbers from Linus Walleij.
- New drivers for Marvell 88PG86x and Qualcomm PM8998 and PMI8998.
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Merge tag 'regulator-v4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator
Pull regulator updates from Mark Brown:
"A very small set of updates for the regulator API this time around,
there's a few bug fixes and also:
- Conversion of the regulator API to use GPIO descriptors rather than
numbers from Linus Walleij.
- New drivers for Marvell 88PG86x and Qualcomm PM8998 and PMI8998"
* tag 'regulator-v4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator:
regulator: qcom: smd: Add pm8998 and pmi8998 regulators
regulator: core: Add missing blank line between functions
regulator: qcom_smd: Drop regulator/{machine,of_regulator} includes
regulator: giving regulator controlling gpios a non-empty label when used through the devicetree.
regulator: gpio: Fix some error handling paths in 'gpio_regulator_probe()'
regulator: 88pg86x: new i2c dual regulator chip
regulator: 88pg86x: add DT bindings document
regulator: da9211: Pass descriptors instead of GPIO numbers
regulator: da9055: Pass descriptor instead of GPIO number
regulator: core: Support passing an initialized GPIO enable descriptor
regulator: dt: regulator-name is required property
regulator: of: Add a missing 'of_node_put()' in an error handling path of 'of_regulator_match()'
This is a fairly large set of updates for regmap, mainly bugfixes. The
biggest bit of this is some fixes for the bulk operations code which
had issues in some use cases, Charles Keepax has sorted them out. We
also gained the ability to use debugfs with syscon regmaps and to
specify the clock to be used with MMIO regmaps.
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Merge tag 'regmap-v4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap
Pull regmap updates from Mark Brown:
"This is a fairly large set of updates for regmap, mainly bugfixes.
The biggest bit of this is some fixes for the bulk operations code
which had issues in some use cases, Charles Keepax has sorted them
out. We also gained the ability to use debugfs with syscon regmaps and
to specify the clock to be used with MMIO regmaps"
* tag 'regmap-v4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap: (21 commits)
regmap: debugfs: Improve warning message on debugfs_create_dir() failure
regmap: debugfs: Free map->debugfs_name when debugfs_create_dir() failed
regmap: debugfs: Don't leak dummy names
regmap: debugfs: Disambiguate dummy debugfs file name
regmap: mmio: Add function to attach a clock
regmap: Merge redundant handling in regmap_bulk_write
regmap: Tidy up regmap_raw_write chunking code
regmap: Move the handling for max_raw_write into regmap_raw_write
regmap: Remove unnecessary printk for failed allocation
regmap: Format data for raw write in regmap_bulk_write
regmap: use debugfs even when no device
regmap: Allow missing device in regmap_name_read_file()
regmap: Use _regmap_read in regmap_bulk_read
regmap: Tidy up regmap_raw_read chunking code
regmap: Move the handling for max_raw_read into regmap_raw_read
regmap: Use helper function for register offset
regmap: Don't use format_val in regmap_bulk_read
regmap: Correct comparison in regmap_cached
regmap: Correct offset handling in regmap_volatile_range
regmap-i2c: Off by one in regmap_i2c_smbus_i2c_read/write()
...
- Modify the cpuidle poll state implementation to prevent CPUs from
staying in the loop in there for excessive times (Rafael Wysocki).
- Add Intel Cannon Lake chips support to the RAPL power capping
driver (Joe Konno).
- Add reference counting to the device links handling code in the
PM core (Lukas Wunner).
- Avoid reconfiguring GPEs on suspend-to-idle in the ACPI system
suspend code (Rafael Wysocki).
- Allow devices to be put into deeper low-power states via ACPI
if both _SxD and _SxW are missing (Daniel Drake).
- Reorganize the core ACPI suspend-to-idle wakeup code to avoid a
keyboard wakeup issue on Asus UX331UA (Chris Chiu).
- Prevent the PCMCIA library code from aborting suspend-to-idle due
to noirq suspend failures resulting from incorrect assumptions
(Rafael Wysocki).
- Add coupled cpuidle supprt to the Exynos3250 platform (Marek
Szyprowski).
- Add new sysfs file to make it easier to specify the image storage
location during hibernation (Mario Limonciello).
- Add sysfs files for collecting suspend-to-idle usage and time
statistics for CPU idle states (Rafael Wysocki).
- Update the pm-graph utilities (Todd Brandt).
- Reduce the kernel log noise related to reporting Low-power Idle
constraings by the ACPI system suspend code (Rafael Wysocki).
- Make it easier to distinguish dedicated wakeup IRQs in the
/proc/interrupts output (Tony Lindgren).
- Add the frequency table validation in cpufreq to the core and
drop it from a number of cpufreq drivers (Viresh Kumar).
- Drop "cooling-{min|max}-level" for CPU nodes from a couple of
DT bindings (Viresh Kumar).
- Clean up the CPU online error code path in the cpufreq core
(Viresh Kumar).
- Fix assorted issues in the SCPI, CPPC, mediatek and tegra186
cpufreq drivers (Arnd Bergmann, Chunyu Hu, George Cherian,
Viresh Kumar).
- Drop memory allocation error messages from a few places in
cpufreq and cpuildle drivers (Markus Elfring).
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Merge tag 'pm-4.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management updates from Rafael Wysocki:
"These update the cpuidle poll state definition to reduce excessive
energy usage related to it, add new CPU ID to the RAPL power capping
driver, update the ACPI system suspend code to handle some special
cases better, extend the PM core's device links code slightly, add new
sysfs attribute for better suspend-to-idle diagnostics and easier
hibernation handling, update power management tools and clean up
cpufreq quite a bit.
Specifics:
- Modify the cpuidle poll state implementation to prevent CPUs from
staying in the loop in there for excessive times (Rafael Wysocki).
- Add Intel Cannon Lake chips support to the RAPL power capping
driver (Joe Konno).
- Add reference counting to the device links handling code in the PM
core (Lukas Wunner).
- Avoid reconfiguring GPEs on suspend-to-idle in the ACPI system
suspend code (Rafael Wysocki).
- Allow devices to be put into deeper low-power states via ACPI if
both _SxD and _SxW are missing (Daniel Drake).
- Reorganize the core ACPI suspend-to-idle wakeup code to avoid a
keyboard wakeup issue on Asus UX331UA (Chris Chiu).
- Prevent the PCMCIA library code from aborting suspend-to-idle due
to noirq suspend failures resulting from incorrect assumptions
(Rafael Wysocki).
- Add coupled cpuidle supprt to the Exynos3250 platform (Marek
Szyprowski).
- Add new sysfs file to make it easier to specify the image storage
location during hibernation (Mario Limonciello).
- Add sysfs files for collecting suspend-to-idle usage and time
statistics for CPU idle states (Rafael Wysocki).
- Update the pm-graph utilities (Todd Brandt).
- Reduce the kernel log noise related to reporting Low-power Idle
constraings by the ACPI system suspend code (Rafael Wysocki).
- Make it easier to distinguish dedicated wakeup IRQs in the
/proc/interrupts output (Tony Lindgren).
- Add the frequency table validation in cpufreq to the core and drop
it from a number of cpufreq drivers (Viresh Kumar).
- Drop "cooling-{min|max}-level" for CPU nodes from a couple of DT
bindings (Viresh Kumar).
- Clean up the CPU online error code path in the cpufreq core (Viresh
Kumar).
- Fix assorted issues in the SCPI, CPPC, mediatek and tegra186
cpufreq drivers (Arnd Bergmann, Chunyu Hu, George Cherian, Viresh
Kumar).
- Drop memory allocation error messages from a few places in cpufreq
and cpuildle drivers (Markus Elfring)"
* tag 'pm-4.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (56 commits)
ACPI / PM: Fix keyboard wakeup from suspend-to-idle on ASUS UX331UA
cpufreq: CPPC: Use transition_delay_us depending transition_latency
PM / hibernate: Change message when writing to /sys/power/resume
PM / hibernate: Make passing hibernate offsets more friendly
cpuidle: poll_state: Avoid invoking local_clock() too often
PM: cpuidle/suspend: Add s2idle usage and time state attributes
cpuidle: Enable coupled cpuidle support on Exynos3250 platform
cpuidle: poll_state: Add time limit to poll_idle()
cpufreq: tegra186: Don't validate the frequency table twice
cpufreq: speedstep: Don't validate the frequency table twice
cpufreq: sparc: Don't validate the frequency table twice
cpufreq: sh: Don't validate the frequency table twice
cpufreq: sfi: Don't validate the frequency table twice
cpufreq: scpi: Don't validate the frequency table twice
cpufreq: sc520: Don't validate the frequency table twice
cpufreq: s3c24xx: Don't validate the frequency table twice
cpufreq: qoirq: Don't validate the frequency table twice
cpufreq: pxa: Don't validate the frequency table twice
cpufreq: ppc_cbe: Don't validate the frequency table twice
cpufreq: powernow: Don't validate the frequency table twice
...
- Update the in-kernel ACPICA code to upstream revision 20180313
including:
* Module-level AML code handling fixes and simplifications (Bob
Moore, Erik Schmauss).
* Fixes and cleanups related to messaging (Bob Moore).
* Events handling fixes related to disabling and enabling GPEs
(Erik Schmauss).
* Introduction of SPDX license identifiers and removal of license
boilerplate in multiple files (Erik Schmauss).
* Assorted fixes and cleanups (Bob Moore, Erik Schmauss, Hans
de Goede, Seunghun Han).
- Add new basic driver for the ACPI Time and Alarm Device (Rafael
Wysocki).
- Modify the ACPI battery driver to support battery thresholds on
Lenovo ThinkPads (Ognjen Galic, Colin Ian King).
- Avoid reporting battery capacity over 100 in the ACPI battery
driver in some cases (Laszlo Toth).
- Make the kernel recognize an OEM _OSI string from Dell to avoid
power management issues with NVidia GPUs in Dell platforms (Alex
Hung).
- Make the PCI IRQ management code handle missing _PRS cleanly (Alex
Hung).
- Fix uevent notifications related to device hotplut (Lee, Chun-Yi).
- Prevent the ACPI PAD driver from leaking memory (Lenny Szubowicz).
- Update the ACPI CPPC library code to include subspace IDs in the
kernel messages logged by it (George Cherian).
- Add backlight quirk for Samsung 670Z5E (Hans de Goede).
- Add the NFIT and HMAT tables to the list of ACPI tables that can
be overridden via initrd (Dan Williams).
- Fix and clean up some ACPI documentation and Kconfig help language
(Aishwarya Pant, Randy Dunlap).
- Replace license boilerplate with an SPDX license ID in the ACPI
PMIC operation region handling code (Rajmohan Mani).
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Merge tag 'acpi-4.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull ACPI updates from Rafael Wysocki:
"These update the ACPICA code in the kernel to follow upstream revision
20180313 which includes fixes related to the so-called module-level
AML (mostly "if" type of statements outside of any methods) that
should improve the handling of systems that load alternative SSDTs
depending on the current configuration, for example, and event
handling fixes related to disabling and enabling GPEs on system
startup and on suspend/resume.
Moreover, the ACPICA license boilerplate is replaced with SPDX license
IDs which alone reduces the number of lines of ACPICA code in the
kernel quite a bit.
Also added is a new driver for the generic ACPI Time and Alarm Device
(TAD). At the moment it only handles the most basic capabilities of
the TAD, however.
In addition to that the ACPI battery driver is improved to handle
battery thresholds on ThinkPads, among other things, some bugs are
fixed, a new backlight quirk is added and some documentation is
updated.
Specifics:
- Update the in-kernel ACPICA code to upstream revision 20180313
including:
* Module-level AML code handling fixes and simplifications (Bob
Moore, Erik Schmauss).
* Fixes and cleanups related to messaging (Bob Moore).
* Events handling fixes related to disabling and enabling GPEs
(Erik Schmauss).
* Introduction of SPDX license identifiers and removal of license
boilerplate in multiple files (Erik Schmauss).
* Assorted fixes and cleanups (Bob Moore, Erik Schmauss, Hans de
Goede, Seunghun Han).
- Add new basic driver for the ACPI Time and Alarm Device (Rafael
Wysocki).
- Modify the ACPI battery driver to support battery thresholds on
Lenovo ThinkPads (Ognjen Galic, Colin Ian King).
- Avoid reporting battery capacity over 100 in the ACPI battery
driver in some cases (Laszlo Toth).
- Make the kernel recognize an OEM _OSI string from Dell to avoid
power management issues with NVidia GPUs in Dell platforms (Alex
Hung).
- Make the PCI IRQ management code handle missing _PRS cleanly (Alex
Hung).
- Fix uevent notifications related to device hotplut (Lee, Chun-Yi).
- Prevent the ACPI PAD driver from leaking memory (Lenny Szubowicz).
- Update the ACPI CPPC library code to include subspace IDs in the
kernel messages logged by it (George Cherian).
- Add backlight quirk for Samsung 670Z5E (Hans de Goede).
- Add the NFIT and HMAT tables to the list of ACPI tables that can be
overridden via initrd (Dan Williams).
- Fix and clean up some ACPI documentation and Kconfig help language
(Aishwarya Pant, Randy Dunlap).
- Replace license boilerplate with an SPDX license ID in the ACPI
PMIC operation region handling code (Rajmohan Mani)"
* tag 'acpi-4.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (39 commits)
ACPI: acpi_pad: Fix memory leak in power saving threads
ACPI / video: Add quirk to force acpi-video backlight on Samsung 670Z5E
ACPI: Add Time and Alarm Device (TAD) driver
ACPI / scan: Send change uevent with offine environmental data
ACPI / Kconfig: Update ACPI_PROCFS_POWER help text
ACPI / OSI: Add OEM _OSI strings to disable NVidia RTD3
ACPICA: Update version to 20180313
ACPICA: Cleanup/simplify module-level code support
ACPICA: Events: add a return on failure from acpi_hw_register_read
ACPICA: adding SPDX headers
ACPICA: Rename a global for clarity, no functional change
ACPICA: macros: fix ACPI_ERROR_NAMESPACE macro
ACPICA: Change a compile-time option to a runtime option
ACPICA: Remove calling of _STA from acpi_get_object_info()
ACPICA: AML Debug Object: Don't ignore output of zero-length strings
ACPICA: Fix memory leak on unusual memory leak
ACPICA: Events: Dispatch GPEs after enabling for the first time
ACPICA: Events: Add parallel GPE handling support to fix potential redundant _Exx evaluations
ACPICA: Events: Stop unconditionally clearing ACPI IRQs during suspend/resume
ACPICA: acpi: acpica: fix acpi operand cache leak in nseval.c
...
The device tree code looks for CONFIG_CMDLINE_FORCE, but we were using
CONFIG_CMDLINE_OVERRIDE. It looks like this was just a hold over from
before our device tree conversion -- in fact, we'd already removed the
support for CONFIG_CMDLINE_OVERRIDE from our arch-specific code so it
didn't even work any more.
Thanks to Mortiz and Trung for finding the original bug, and for Michael
for suggeting a better fix.
CC: Trung Tran <trung.tran@ettus.com>
CC: Michael J Clark <mjc@sifive.com>
Reviewed-by: Moritz Fischer <mdf@kernel.org>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
This avoids a lot of -Wunused warnings such as:
====================
kernel/debug/debug_core.c: In function ‘kgdb_cpu_enter’:
./arch/sparc/include/asm/cmpxchg_64.h:55:22: warning: value computed is not used [-Wunused-value]
#define xchg(ptr,x) ((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr))))
./arch/sparc/include/asm/atomic_64.h:86:30: note: in expansion of macro ‘xchg’
#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
^~~~
kernel/debug/debug_core.c:508:4: note: in expansion of macro ‘atomic_xchg’
atomic_xchg(&kgdb_active, cpu);
^~~~~~~~~~~
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
The PCM runtime object is created and freed dynamically at PCM stream
open / close time. This is tracked via substream->runtime, and it's
cleared at snd_pcm_detach_substream().
The runtime object assignment is protected by PCM open_mutex, so for
all PCM operations, it's safely handled. However, each PCM substream
provides also an ALSA timer interface, and user-space can access to
this while closing a PCM substream. This may eventually lead to a
UAF, as snd_pcm_timer_resolution() tries to access the runtime while
clearing it in other side.
Fortunately, it's the only concurrent access from the PCM timer, and
it merely reads runtime->timer_resolution field. So, we can avoid the
race by reordering kfree() and wrapping the substream->runtime
clearance with the corresponding timer lock.
Reported-by: syzbot+8e62ff4e07aa2ce87826@syzkaller.appspotmail.com
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Pull removal of in-kernel calls to syscalls from Dominik Brodowski:
"System calls are interaction points between userspace and the kernel.
Therefore, system call functions such as sys_xyzzy() or
compat_sys_xyzzy() should only be called from userspace via the
syscall table, but not from elsewhere in the kernel.
At least on 64-bit x86, it will likely be a hard requirement from
v4.17 onwards to not call system call functions in the kernel: It is
better to use use a different calling convention for system calls
there, where struct pt_regs is decoded on-the-fly in a syscall wrapper
which then hands processing over to the actual syscall function. This
means that only those parameters which are actually needed for a
specific syscall are passed on during syscall entry, instead of
filling in six CPU registers with random user space content all the
time (which may cause serious trouble down the call chain). Those
x86-specific patches will be pushed through the x86 tree in the near
future.
Moreover, rules on how data may be accessed may differ between kernel
data and user data. This is another reason why calling sys_xyzzy() is
generally a bad idea, and -- at most -- acceptable in arch-specific
code.
This patchset removes all in-kernel calls to syscall functions in the
kernel with the exception of arch/. On top of this, it cleans up the
three places where many syscalls are referenced or prototyped, namely
kernel/sys_ni.c, include/linux/syscalls.h and include/linux/compat.h"
* 'syscalls-next' of git://git.kernel.org/pub/scm/linux/kernel/git/brodo/linux: (109 commits)
bpf: whitelist all syscalls for error injection
kernel/sys_ni: remove {sys_,sys_compat} from cond_syscall definitions
kernel/sys_ni: sort cond_syscall() entries
syscalls/x86: auto-create compat_sys_*() prototypes
syscalls: sort syscall prototypes in include/linux/compat.h
net: remove compat_sys_*() prototypes from net/compat.h
syscalls: sort syscall prototypes in include/linux/syscalls.h
kexec: move sys_kexec_load() prototype to syscalls.h
x86/sigreturn: use SYSCALL_DEFINE0
x86: fix sys_sigreturn() return type to be long, not unsigned long
x86/ioport: add ksys_ioperm() helper; remove in-kernel calls to sys_ioperm()
mm: add ksys_readahead() helper; remove in-kernel calls to sys_readahead()
mm: add ksys_mmap_pgoff() helper; remove in-kernel calls to sys_mmap_pgoff()
mm: add ksys_fadvise64_64() helper; remove in-kernel call to sys_fadvise64_64()
fs: add ksys_fallocate() wrapper; remove in-kernel calls to sys_fallocate()
fs: add ksys_p{read,write}64() helpers; remove in-kernel calls to syscalls
fs: add ksys_truncate() wrapper; remove in-kernel calls to sys_truncate()
fs: add ksys_sync_file_range helper(); remove in-kernel calls to syscall
kernel: add ksys_setsid() helper; remove in-kernel call to sys_setsid()
kernel: add ksys_unshare() helper; remove in-kernel calls to sys_unshare()
...
Commit 2a98dc028f ("include/linux/bitmap.h: turn bitmap_set and
bitmap_clear into memset when possible") introduced an optimization to
bitmap_{set,clear}() which uses memset() when the start and length are
constants aligned to a byte.
This is wrong on big-endian systems; our bitmaps are arrays of unsigned
long, so bit n is not at byte n / 8 in memory. This was caught by the
Btrfs selftests, but the bitmap selftests also fail when run on a
big-endian machine.
We can still use memset if the start and length are aligned to an
unsigned long, so do that on big-endian. The same problem applies to
the memcmp in bitmap_equal(), so fix it there, too.
Fixes: 2a98dc028f ("include/linux/bitmap.h: turn bitmap_set and bitmap_clear into memset when possible")
Fixes: 2c6deb0152 ("bitmap: use memcmp optimisation in more situations")
Cc: stable@kernel.org
Reported-by: "Erhard F." <erhard_f@mailbox.org>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This cleans up the module support that was commited earlier to work with
what's actually emitted from our GCC port as it lands upstream. Most of
the work here is adding new relocations to the kernel.
There's some limitations on module loading imposed by the kernel:
* The kernel doesn't support linker relaxation, which is necessary to
support R_RISCV_ALIGN. In order to get reliable module building
you're going to need to a GCC that supports the new '-mno-relax',
which IIRC isn't going to be out until 8.1.0. It's somewhat unlikely
that R_RISCV_ALIGN will appear in a module even without '-mno-relax'
support, so issues shouldn't be common.
* There is no large code model for RISC-V, which means modules must be
loaded within a 32-bit signed offset of the kernel. We don't
currently have any mechanism for ensuring this memory remains free or
moving pages around, so issues here might be common.
I fixed a singcle merge conflict in arch/riscv/kernel/Makefile.
These fixes fall into three categories
* The definiton of __smp_{store_release,load_acquire}, which allow us to
emit a full fence when unnecessary.
* Fixes to avoid relying on the behavior of "*.aqrl" atomics, as those
are specified in the currently released RISC-V memory model draft in
a way that makes them useless for Linux. This might change in the
future, but now the code matches the memory model spec as it's written
so at least we're getting closer to something sane. The actual fix is
to delete the RISC-V specific atomics and drop back to generic
versions that use the new fences from above.
* Cleanups to our atomic macros, which are mostly non-functional
changes.
Unfortunately I haven't given these as thorough of a testing as I
probably should have, but I've poked through the code and they seem
generally OK.
This patch set includes the building blocks of dynamic ftrace features
for RISC-V machines. I'm afraid I'm not very familiar with ftrace, but
the code looks OK to me. It's been used to track down a performance
problem in our SPI driver and appears to work acceptably, but we haven't
given it a whole lot of banging yet so there might still be some bugs
lurking around somewhere.
This removes the entire architecture code for blackfin, cris, frv, m32r,
metag, mn10300, score, and tile, including the associated device drivers.
I have been working with the (former) maintainers for each one to ensure
that my interpretation was right and the code is definitely unused in
mainline kernels. Many had fond memories of working on the respective
ports to start with and getting them included in upstream, but also saw
no point in keeping the port alive without any users.
In the end, it seems that while the eight architectures are extremely
different, they all suffered the same fate: There was one company
in charge of an SoC line, a CPU microarchitecture and a software
ecosystem, which was more costly than licensing newer off-the-shelf
CPU cores from a third party (typically ARM, MIPS, or RISC-V). It seems
that all the SoC product lines are still around, but have not used the
custom CPU architectures for several years at this point. In contrast,
CPU instruction sets that remain popular and have actively maintained
kernel ports tend to all be used across multiple licensees.
The removal came out of a discussion that is now documented at
https://lwn.net/Articles/748074/. Unlike the original plans, I'm not
marking any ports as deprecated but remove them all at once after I made
sure that they are all unused. Some architectures (notably tile, mn10300,
and blackfin) are still being shipped in products with old kernels,
but those products will never be updated to newer kernel releases.
After this series, we still have a few architectures without mainline
gcc support:
- unicore32 and hexagon both have very outdated gcc releases, but the
maintainers promised to work on providing something newer. At least
in case of hexagon, this will only be llvm, not gcc.
- openrisc, risc-v and nds32 are still in the process of finishing their
support or getting it added to mainline gcc in the first place.
They all have patched gcc-7.3 ports that work to some degree, but
complete upstream support won't happen before gcc-8.1. Csky posted
their first kernel patch set last week, their situation will be similar.
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Merge tag 'arch-removal' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic
Pul removal of obsolete architecture ports from Arnd Bergmann:
"This removes the entire architecture code for blackfin, cris, frv,
m32r, metag, mn10300, score, and tile, including the associated device
drivers.
I have been working with the (former) maintainers for each one to
ensure that my interpretation was right and the code is definitely
unused in mainline kernels. Many had fond memories of working on the
respective ports to start with and getting them included in upstream,
but also saw no point in keeping the port alive without any users.
In the end, it seems that while the eight architectures are extremely
different, they all suffered the same fate: There was one company in
charge of an SoC line, a CPU microarchitecture and a software
ecosystem, which was more costly than licensing newer off-the-shelf
CPU cores from a third party (typically ARM, MIPS, or RISC-V). It
seems that all the SoC product lines are still around, but have not
used the custom CPU architectures for several years at this point. In
contrast, CPU instruction sets that remain popular and have actively
maintained kernel ports tend to all be used across multiple licensees.
[ See the new nds32 port merged in the previous commit for the next
generation of "one company in charge of an SoC line, a CPU
microarchitecture and a software ecosystem" - Linus ]
The removal came out of a discussion that is now documented at
https://lwn.net/Articles/748074/. Unlike the original plans, I'm not
marking any ports as deprecated but remove them all at once after I
made sure that they are all unused. Some architectures (notably tile,
mn10300, and blackfin) are still being shipped in products with old
kernels, but those products will never be updated to newer kernel
releases.
After this series, we still have a few architectures without mainline
gcc support:
- unicore32 and hexagon both have very outdated gcc releases, but the
maintainers promised to work on providing something newer. At least
in case of hexagon, this will only be llvm, not gcc.
- openrisc, risc-v and nds32 are still in the process of finishing
their support or getting it added to mainline gcc in the first
place. They all have patched gcc-7.3 ports that work to some
degree, but complete upstream support won't happen before gcc-8.1.
Csky posted their first kernel patch set last week, their situation
will be similar
[ Palmer Dabbelt points out that RISC-V support is in mainline gcc
since gcc-7, although gcc-7.3.0 is the recommended minimum - Linus ]"
This really says it all:
2498 files changed, 95 insertions(+), 467668 deletions(-)
* tag 'arch-removal' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: (74 commits)
MAINTAINERS: UNICORE32: Change email account
staging: iio: remove iio-trig-bfin-timer driver
tty: hvc: remove tile driver
tty: remove bfin_jtag_comm and hvc_bfin_jtag drivers
serial: remove tile uart driver
serial: remove m32r_sio driver
serial: remove blackfin drivers
serial: remove cris/etrax uart drivers
usb: Remove Blackfin references in USB support
usb: isp1362: remove blackfin arch glue
usb: musb: remove blackfin port
usb: host: remove tilegx platform glue
pwm: remove pwm-bfin driver
i2c: remove bfin-twi driver
spi: remove blackfin related host drivers
watchdog: remove bfin_wdt driver
can: remove bfin_can driver
mmc: remove bfin_sdh driver
input: misc: remove blackfin rotary driver
input: keyboard: remove bf54x driver
...
In make_dentry_ptr_block, it is confused with "&" for t->dentry_bitmap
but without "&" for t->dentry, so delete "&" to make code more readable.
Signed-off-by: Yunlong Song <yunlong.song@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
If write is failed, we must deallocate the blocks that we couldn't write.
Cc: stable@vger.kernel.org
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Just fail on align type. Kernel modules loader didn't do relax
like linker, it is difficult to remove or migrate the code,
but the remnant nop instructions harm the performaace of module.
We expect the building module with the no-relax option.
Signed-off-by: Zong Li <zong@andestech.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
HI20 and LO12_I/LO12_S relocate the absolute address, the range of
offset must in 32-bit.
Signed-off-by: Zong Li <zong@andestech.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
For CALL_PLT, emit the plt entry only when offset is more than 32-bit.
For PCREL_LO12, it uses the location of corresponding HI20 to
get the address of external symbol. It should check the HI20 type
is the PCREL_HI20 or GOT_HI20, because sometime the location will
have two or more relocation types.
For example:
0: 00000797 auipc a5,0x0
0: R_RISCV_ALIGN *ABS*
0: R_RISCV_GOT_HI20 SYMBOL
4: 0007b783 ld a5,0(a5) # 0 <SYMBOL>
4: R_RISCV_PCREL_LO12_I .L0
4: R_RISCV_RELAX *ABS*
Signed-off-by: Zong Li <zong@andestech.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
Separate the function symbol address from .plt to .got.plt section.
The original plt entry has trampoline code with symbol address,
there is a 32-bit padding bwtween jar instruction and symbol address.
Extract the symbol address to .got.plt to reduce the module size.
Signed-off-by: Zong Li <zong@andestech.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
The address of external symbols will locate more than 32-bit offset
in 64-bit kernel with sv39 or sv48 virtual addressing.
Module loader emits the GOT and PLT entries for data symbols and
function symbols respectively.
The PLT entry is a trampoline code for jumping to the 64-bit
real address. The GOT entry is just the data symbol address.
Signed-off-by: Zong Li <zong@andestech.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
Atomics present the same issue with locking: release and acquire
variants need to be strengthened to meet the constraints defined
by the Linux-kernel memory consistency model [1].
Atomics present a further issue: implementations of atomics such
as atomic_cmpxchg() and atomic_add_unless() rely on LR/SC pairs,
which do not give full-ordering with .aqrl; for example, current
implementations allow the "lr-sc-aqrl-pair-vs-full-barrier" test
below to end up with the state indicated in the "exists" clause.
In order to "synchronize" LKMM and RISC-V's implementation, this
commit strengthens the implementations of the atomics operations
by replacing .rl and .aq with the use of ("lightweigth") fences,
and by replacing .aqrl LR/SC pairs in sequences such as:
0: lr.w.aqrl %0, %addr
bne %0, %old, 1f
...
sc.w.aqrl %1, %new, %addr
bnez %1, 0b
1:
with sequences of the form:
0: lr.w %0, %addr
bne %0, %old, 1f
...
sc.w.rl %1, %new, %addr /* SC-release */
bnez %1, 0b
fence rw, rw /* "full" fence */
1:
following Daniel's suggestion.
These modifications were validated with simulation of the RISC-V
memory consistency model.
C lr-sc-aqrl-pair-vs-full-barrier
{}
P0(int *x, int *y, atomic_t *u)
{
int r0;
int r1;
WRITE_ONCE(*x, 1);
r0 = atomic_cmpxchg(u, 0, 1);
r1 = READ_ONCE(*y);
}
P1(int *x, int *y, atomic_t *v)
{
int r0;
int r1;
WRITE_ONCE(*y, 1);
r0 = atomic_cmpxchg(v, 0, 1);
r1 = READ_ONCE(*x);
}
exists (u=1 /\ v=1 /\ 0:r1=0 /\ 1:r1=0)
[1] https://marc.info/?l=linux-kernel&m=151930201102853&w=2https://groups.google.com/a/groups.riscv.org/forum/#!topic/isa-dev/hKywNHBkAXMhttps://marc.info/?l=linux-kernel&m=151633436614259&w=2
Suggested-by: Daniel Lustig <dlustig@nvidia.com>
Signed-off-by: Andrea Parri <parri.andrea@gmail.com>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Albert Ou <albert@sifive.com>
Cc: Daniel Lustig <dlustig@nvidia.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Jade Alglave <j.alglave@ucl.ac.uk>
Cc: Luc Maranget <luc.maranget@inria.fr>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Akira Yokosawa <akiyks@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-riscv@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
Current implementations map locking operations using .rl and .aq
annotations. However, this mapping is unsound w.r.t. the kernel
memory consistency model (LKMM) [1]:
Referring to the "unlock-lock-read-ordering" test reported below,
Daniel wrote:
"I think an RCpc interpretation of .aq and .rl would in fact
allow the two normal loads in P1 to be reordered [...]
The intuition would be that the amoswap.w.aq can forward from
the amoswap.w.rl while that's still in the store buffer, and
then the lw x3,0(x4) can also perform while the amoswap.w.rl
is still in the store buffer, all before the l1 x1,0(x2)
executes. That's not forbidden unless the amoswaps are RCsc,
unless I'm missing something.
Likewise even if the unlock()/lock() is between two stores.
A control dependency might originate from the load part of
the amoswap.w.aq, but there still would have to be something
to ensure that this load part in fact performs after the store
part of the amoswap.w.rl performs globally, and that's not
automatic under RCpc."
Simulation of the RISC-V memory consistency model confirmed this
expectation.
In order to "synchronize" LKMM and RISC-V's implementation, this
commit strengthens the implementations of the locking operations
by replacing .rl and .aq with the use of ("lightweigth") fences,
resp., "fence rw, w" and "fence r , rw".
C unlock-lock-read-ordering
{}
/* s initially owned by P1 */
P0(int *x, int *y)
{
WRITE_ONCE(*x, 1);
smp_wmb();
WRITE_ONCE(*y, 1);
}
P1(int *x, int *y, spinlock_t *s)
{
int r0;
int r1;
r0 = READ_ONCE(*y);
spin_unlock(s);
spin_lock(s);
r1 = READ_ONCE(*x);
}
exists (1:r0=1 /\ 1:r1=0)
[1] https://marc.info/?l=linux-kernel&m=151930201102853&w=2https://groups.google.com/a/groups.riscv.org/forum/#!topic/isa-dev/hKywNHBkAXMhttps://marc.info/?l=linux-kernel&m=151633436614259&w=2
Signed-off-by: Andrea Parri <parri.andrea@gmail.com>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Albert Ou <albert@sifive.com>
Cc: Daniel Lustig <dlustig@nvidia.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Jade Alglave <j.alglave@ucl.ac.uk>
Cc: Luc Maranget <luc.maranget@inria.fr>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Akira Yokosawa <akiyks@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-riscv@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
Introduce __smp_{store_release,load_acquire}, and rely on the generic
definitions for smp_{store_release,load_acquire}. This avoids the use
of full ("rw,rw") fences on SMP.
Signed-off-by: Andrea Parri <parri.andrea@gmail.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
In walk_stackframe, the pc now receives the address from calling
ftrace_graph_ret_addr instead of manual calculation.
Note that the original calculation,
pc = frame->ra - 4
is buggy when the instruction at the return address happened to be a
compressed inst. But since it is not a critical part of ftrace, it is
ignored for now to ease the review process.
Cc: Greentime Hu <greentime@andestech.com>
Signed-off-by: Alan Kao <alankao@andestech.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
Once the function_graph tracer is enabled, a filtered function has the
following call sequence:
* ftracer_caller ==> on/off by ftrace_make_call/ftrace_make_nop
* ftrace_graph_caller
* ftrace_graph_call ==> on/off by ftrace_en/disable_ftrace_graph_caller
* prepare_ftrace_return
Considering the following DYNAMIC_FTRACE_WITH_REGS feature, it would be
more extendable to have a ftrace_graph_caller function, instead of
calling prepare_ftrace_return directly in ftrace_caller.
Cc: Greentime Hu <greentime@andestech.com>
Signed-off-by: Alan Kao <alankao@andestech.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
We now have dynamic ftrace with the following added items:
* ftrace_make_call, ftrace_make_nop (in kernel/ftrace.c)
The two functions turn each recorded call site of filtered functions
into a call to ftrace_caller or nops
* ftracce_update_ftrace_func (in kernel/ftrace.c)
turns the nops at ftrace_call into a call to a generic entry for
function tracers.
* ftrace_caller (in kernel/mcount-dyn.S)
The entry where each _mcount call sites calls to once they are
filtered to be traced.
Also, this patch fixes the semantic problems in mcount.S, which will be
treated as only a reference implementation once we have the dynamic
ftrace.
Cc: Greentime Hu <greentime@andestech.com>
Signed-off-by: Alan Kao <alankao@andestech.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
Now recordmcount.pl recognizes RISC-V object files. For the mechanism to
work, we have to disable the linker relaxation.
Cc: Greentime Hu <greentime@andestech.com>
Signed-off-by: Alan Kao <alankao@andestech.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>