Reverse the two members to remove a hole.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Reviewed-by: Péter Ujfalusi <peter.ujfalusi@linux.intel.com>
Link: https://patch.msgid.link/20240802124609.188954-3-pierre-louis.bossart@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
reshuffle members to remove hole.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Reviewed-by: Péter Ujfalusi <peter.ujfalusi@linux.intel.com>
Link: https://patch.msgid.link/20240802124609.188954-2-pierre-louis.bossart@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
This patch adds match table for rt722 multiple function codec on link
0 and link3.
The topology does not internally refer to link0 or link3, so we can
simplify and use the same topology file name. We do need different
tables though.
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Reviewed-by: Péter Ujfalusi <peter.ujfalusi@linux.intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://patch.msgid.link/20240802124011.173820-6-pierre-louis.bossart@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
PTL has some differences from MTL/LNL. Need to use different register
to power up.
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Reviewed-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Reviewed-by: Péter Ujfalusi <peter.ujfalusi@linux.intel.com>
Signed-off-by: Fred Oh <fred.oh@linux.intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://patch.msgid.link/20240802124011.173820-3-pierre-louis.bossart@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
For now the tables are basic for mockup devices and headset codec support
Reviewed-by: Péter Ujfalusi <peter.ujfalusi@linux.intel.com>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Reviewed-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://patch.msgid.link/20240802124011.173820-2-pierre-louis.bossart@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
The microphone/speaker privacy shutter ALSA control handlers need to
call pm_runtime_resume, since the hardware needs to be powered up to
check the hardware state of the shutter. The IRQ handler for the
shutters also needs to notify the ALSA control to inform user-space
the shutters updated. However this leads to a mutex inversion,
between the sdw_dev_lock and the controls_rwsem.
To avoid this mutex inversion cache the kctl pointers before the IRQ
handler, which avoids the need to lookup the control and take the
controls_rwsem.
Suggested-by: Jaroslav Kysela <perex@perex.cz>
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Link: https://patch.msgid.link/20240802105734.2309788-5-ckeepax@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Add new helper functions snd_soc_component_get_kcontrol() and
snd_soc_component_get_kcontrol_locked() that returns a kcontrol
by name, but will factor in the components name_prefix, to handle
situations where multiple components are present with the same
controls.
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Link: https://patch.msgid.link/20240802105734.2309788-3-ckeepax@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Use ID_AA64PFR0_EL1_GIC_V4P1 instead of '3' in gic_cpuif_has_vsgi() to
check for the GIC version.
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/all/20240802085601.1824057-1-anshuman.khandual@arm.com
Commit c055e3eae0 ("crypto: xor - use ktime for template benchmarking")
switched from using jiffies to ktime-based performance benchmarking.
This works nicely on machines which have a fine-grained ktime()
clocksource as e.g. x86 machines with TSC.
But other machines, e.g. my 4-way HP PARISC server, don't have such
fine-grained clocksources, which is why it seems that 800 xor loops
take zero seconds, which then shows up in the logs as:
xor: measuring software checksum speed
8regs : -1018167296 MB/sec
8regs_prefetch : -1018167296 MB/sec
32regs : -1018167296 MB/sec
32regs_prefetch : -1018167296 MB/sec
Fix this with some small modifications to the existing code to improve
the algorithm to always produce correct results without introducing
major delays for architectures with a fine-grained ktime()
clocksource:
a) Delay start of the timing until ktime() just advanced. On machines
with a fast ktime() this should be just one additional ktime() call.
b) Count the number of loops. Run at minimum 800 loops and finish
earliest when the ktime() counter has progressed.
With that the throughput can now be calculated more accurately under all
conditions.
Fixes: c055e3eae0 ("crypto: xor - use ktime for template benchmarking")
Signed-off-by: Helge Deller <deller@gmx.de>
Tested-by: John David Anglin <dave.anglin@bell.net>
v2:
- clean up coding style (noticed & suggested by Herbert Xu)
- rephrased & fixed typo in commit message
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
With ARCH=powerpc, make allmodconfig && make W=1 C=1 reports:
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/cpufreq/ppc-cbe-cpufreq.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/cpufreq/powernv-cpufreq.o
Add the missing invocation of the MODULE_DESCRIPTION() macro to all
files which have a MODULE_LICENSE().
This includes three additional files which, although they did not
produce a warning with the powerpc allmodconfig configuration, may
cause this warning with specific options enabled in the kernel
configuration.
Signed-off-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Link: https://patch.msgid.link/20240722-md-powerpc-drivers-cpufreq-v2-1-bb84d715eb3d@quicinc.com
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
On Intel Emerald Rapids machines, we ship the Energy Performance Preference
(EPP) default for balance_performance as 128. However, during an internal
investigation together with Intel, we have determined that 32 is a more
suitable value. This leads to significant improvements in both performance
and energy:
POV-Ray: 32% faster | 12% less energy
OpenSSL: 12% faster | energy within 1%
Build Linux Kernel: 29% faster | 18% less energy
Therefore, we should move the default EPP for balance_performance to 32.
This is in line with what has already been done for Sapphire Rapids.
Signed-off-by: Pedro Henrique Kopper <pedro.kopper@canonical.com>
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Link: https://patch.msgid.link/Zqu6zjVMoiXwROBI@capivara
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Add a few new tests to exercise the signal handler flow, especially with
PKEY 0 disabled:
- Verify that the SIGSEGV handler is invoked when pkey 0 is disabled.
- Verify that a thread which disables PKEY 0 segfaults with PKUERR when
accessing the stack.
- Verify that the SIGSEGV handler that uses an alternate signal stack is
correctly invoked when the thread disabled PKEY 0
- Verify that the PKRU value set by the application is correctly restored
upon return from signal handling.
- Verify that sigreturn() is able to restore the altstack even if the
thread had PKEY 0 disabled
[ Aruna: Adapted to upstream ]
[ tglx: Made it actually compile. Restored protection_keys compile. Added
useful info to the changelog instead of bare function names. ]
Signed-off-by: Keith Lucas <keith.lucas@oracle.com>
Signed-off-by: Aruna Ramakrishna <aruna.ramakrishna@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20240802061318.2140081-6-aruna.ramakrishna@oracle.com
A process can disable access to the alternate signal stack by not
enabling the altstack's PKEY in the PKRU register.
Nevertheless, the kernel updates the PKRU temporarily for signal
handling. However, in sigreturn(), restore_sigcontext() will restore the
PKRU to the user-defined PKRU value.
This will cause restore_altstack() to fail with a SIGSEGV as it needs read
access to the altstack which is prohibited by the user-defined PKRU value.
Fix this by restoring altstack before restoring PKRU.
Signed-off-by: Aruna Ramakrishna <aruna.ramakrishna@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20240802061318.2140081-5-aruna.ramakrishna@oracle.com
If the alternate signal stack is protected by a different PKEY than the
current execution stack, copying XSAVE data to the sigaltstack will fail
if its PKEY is not enabled in the PKRU register.
It's unknown which pkey was used by the application for the altstack, so
enable all PKEYS before XSAVE.
But this updated PKRU value is also pushed onto the sigframe, which
means the register value restored from sigcontext will be different from
the user-defined one, which is incorrect.
Fix that by overwriting the PKRU value on the sigframe with the original,
user-defined PKRU.
Signed-off-by: Aruna Ramakrishna <aruna.ramakrishna@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20240802061318.2140081-4-aruna.ramakrishna@oracle.com
In the case where a user thread sets up an alternate signal stack protected
by the default PKEY (i.e. PKEY 0), while the thread's stack is protected by
a non-zero PKEY, both these PKEYS have to be enabled in the PKRU register
for the signal to be delivered to the application correctly. However, the
PKRU value restored after handling the signal must not enable this extra
PKEY (i.e. PKEY 0) - i.e., the PKRU value in the sigframe has to be
overwritten with the user-defined value.
Add helper functions that will update PKRU value in the sigframe after
XSAVE.
Note that sig_prepare_pkru() makes no assumption about which PKEY could
be used to protect the altstack (i.e. it may not be part of init_pkru),
and so enables all PKEYS.
No functional change.
Signed-off-by: Aruna Ramakrishna <aruna.ramakrishna@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20240802061318.2140081-3-aruna.ramakrishna@oracle.com
Assume there's a multithreaded application that runs untrusted user
code. Each thread has its stack/code protected by a non-zero PKEY, and the
PKRU register is set up such that only that particular non-zero PKEY is
enabled. Each thread also sets up an alternate signal stack to handle
signals, which is protected by PKEY zero. The PKEYs man page documents that
the PKRU will be reset to init_pkru when the signal handler is invoked,
which means that PKEY zero access will be enabled. But this reset happens
after the kernel attempts to push fpu state to the alternate stack, which
is not (yet) accessible by the kernel, which leads to a new SIGSEGV being
sent to the application, terminating it.
Enabling both the non-zero PKEY (for the thread) and PKEY zero in
userspace will not work for this use case. It cannot have the alt stack
writeable by all - the rationale here is that the code running in that
thread (using a non-zero PKEY) is untrusted and should not have access
to the alternate signal stack (that uses PKEY zero), to prevent the
return address of a function from being changed. The expectation is that
kernel should be able to set up the alternate signal stack and deliver
the signal to the application even if PKEY zero is explicitly disabled
by the application. The signal handler accessibility should not be
dictated by whatever PKRU value the thread sets up.
The PKRU register is managed by XSAVE, which means the sigframe contents
must match the register contents - which is not the case here. It's
required that the signal frame contains the user-defined PKRU value (so
that it is restored correctly from sigcontext) but the actual register must
be reset to init_pkru so that the alt stack is accessible and the signal
can be delivered to the application. It seems that the proper fix here
would be to remove PKRU from the XSAVE framework and manage it separately,
which is quite complicated. As a workaround, do this:
orig_pkru = rdpkru();
wrpkru(orig_pkru & init_pkru_value);
xsave_to_user_sigframe();
put_user(pkru_sigframe_addr, orig_pkru)
In preparation for writing PKRU to sigframe, pass PKRU as an additional
parameter down the call chain from get_sigframe().
No functional change.
Signed-off-by: Aruna Ramakrishna <aruna.ramakrishna@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20240802061318.2140081-2-aruna.ramakrishna@oracle.com
There are no more callers of thermal_zone_get_trip() in the tree, so
drop it.
No functional impact.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Link: https://patch.msgid.link/2220301.Mh6RI2rZIc@rjwysocki.net
The only existing caller of thermal_zone_get_num_trips(), which is
rcar_gen3_thermal_probe(), uses this function to put the number of
trip points into a kernel log message, but this information is also
available from the thermal sysfs interface.
For this reason, remove the thermal_zone_get_num_trips() call from
rcar_gen3_thermal_probe() and drop the former altogether.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Link: https://patch.msgid.link/2636988.Lt9SDvczpP@rjwysocki.net
There are no more users of get_thermal_instance(), so drop it.
While at it, replace get_instance() returning a pointer to struct
thermal_instance with thermal_instance_present() returning a bool
which is more straightforward.
No functional impact.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Link: https://patch.msgid.link/2014591.usQuhbGJ8B@rjwysocki.net
[ rjw: Dropped get_thermal_instance() documentation ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
It is generally inefficient to iterate over trip indices and call
thermal_zone_get_trip() every time to get the struct thermal_trip
corresponding to the given trip index, so modify the Tegra thermal
drivers to use thermal_zone_for_each_trip() for walking trips.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Link: https://patch.msgid.link/1819430.VLH7GnMWUR@rjwysocki.net
[ rjw: Dropped an unused local variable ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Introduce a helper structure, struct trip_temps, for storing the
temperatures of the critical and hot trip points.
This helps to make the code in tegra_tsensor_get_hw_channel_trips()
somewhat cleaner and will be useful subsequently in eliminating
iteration over trip indices from the driver.
No intentional functional impact.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Link: https://patch.msgid.link/9333090.CDJkKcVGEf@rjwysocki.net
Modify qpnp_tm_init() to use thermal_zone_get_crit_temp() to get the
critical trip temperature instead of iterating over trip indices and
using thermal_zone_get_trip() to get a struct thermal_trip pointer
from a trip index until it finds the critical one.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Link: https://patch.msgid.link/7712228.EvYhyI6sBW@rjwysocki.net
Modify hisi_thermal_register_sensor() to use thermal_zone_for_each_trip()
for walking trip points instead of iterating over trip indices and using
thermal_zone_get_trip() to get a struct thermal_trip pointer from a trip
index.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Link: https://patch.msgid.link/1994088.PYKUYFuaPT@rjwysocki.net
[ rjw: Dropped two unused local variables ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Modify the bcm2835 thermal driver to use thermal_zone_get_crit_temp() in
bcm2835_thermal_probe() instead of relying on the assumption that the
critical trip index will always be 0.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Link: https://patch.msgid.link/3322893.aeNJFYEL58@rjwysocki.net
The thermal sysfs API document is outdated. One of the problems with
it is that is still documents thermal_zone_device_register() which
does not exit any more and it does not reflect the current thermal
zone operations definition.
Replace the thermal_zone_device_register() description in it with
a thermal_zone_device_register_with_trips() description, including
an update of the thermal zone operations list.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Link: https://patch.msgid.link/2767845.mvXUDI8C0e@rjwysocki.net
If a device has more than one touchring, we want to be sure that userspace
is able to distinguish them. Following previous standards, the first
absolute ring will be reported as ABS_WHEEL and the second as ABS_THROTTLE.
Relative rings will use REL_WHEEL_HI_RES / REL_WHEEL for the first and
REL_HWHEEL_HI_RES / REL_HWHEEL for the second.
Signed-off-by: Jason Gerecke <jason.gerecke@wacom.com>
Signed-off-by: Jiri Kosina <jkosina@suse.com>
Modern userspace (i.e. libinput) will make use of high-resolution
scrolling if supported. Hardware does not currently set a resolution
multiplier needed for effective high-res scrolling, but we can still
write code to support it in the future.
Signed-off-by: Jason Gerecke <jason.gerecke@wacom.com>
Signed-off-by: Jiri Kosina <jkosina@suse.com>
If a touchring is configured to send relative events (e.g. +1 or -1 every
time some bit of rotational distance is covered), we should similarly
send relative events up to userspace. Previous non-HID tablets used
REL_WHEEL to send this kind of information, so we opt to use this same
axis since userspace (xf86-input-wacom and libinput) already expects
this kind of behavior from the Wacom kernel driver.
Signed-off-by: Jason Gerecke <jason.gerecke@wacom.com>
Signed-off-by: Jiri Kosina <jkosina@suse.com>
When we encounter a usage mapped to ABS_X or ABS_Y which has a calculated
resolution of 0, we want to warn the user of this before setting a default
value. The previous language used the word "usage" but then printed out the
value of a "code" instead. We can improve this.
Signed-off-by: Jason Gerecke <jason.gerecke@wacom.com>
Signed-off-by: Jiri Kosina <jkosina@suse.com>
The Wacom driver maps the HID_DG_TWIST usage to ABS_Z (rather than ABS_RZ)
for historic reasons. When the code to support twist was introduced in
commit 50066a042d ("HID: wacom: generic: Add support for height, tilt,
and twist usages"), we were careful to write it in such a way that it had
HID calculate the resolution of the twist axis assuming ABS_RZ instead
(so that we would get correct angular behavior). This was broken with
the introduction of commit 08a46b4190 ("HID: wacom: Set a default
resolution for older tablets"), which moved the resolution calculation
to occur *before* the adjustment from ABS_Z to ABS_RZ occurred.
This commit moves the calculation of resolution after the point that
we are finished setting things up for its proper use.
Signed-off-by: Jason Gerecke <jason.gerecke@wacom.com>
Fixes: 08a46b4190 ("HID: wacom: Set a default resolution for older tablets")
Cc: stable@vger.kernel.org
Signed-off-by: Jiri Kosina <jkosina@suse.com>
GT7868Q has incorrect data in the report and needs a fixup.
The change enables haptic touchpad on Lenovo ThinkBook 13x Gen 4
and has been tested on the device.
Signed-off-by: Dmitry Savin <envelsavinds@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.com>
The new ASUS ROG Ally X functions almost exactly the same as the previous
model, so we can use the same quirks.
Signed-off-by: Luke D. Jones <luke@ljones.dev>
Signed-off-by: Jiri Kosina <jkosina@suse.com>
This helper will allow HID drivers to easily determine if they should
bind to a hid_device by checking for the prescence of a certain field
when its ID is not enough, which can be the case on USB devices with
multiple interfaces and/or configurations.
Convert google-hammer driver to use it, and remove now superfluous
hammer_has_usage().
[jkosina@suse.com: expand changelog with the information about
google-hammer being added as user of this API ]
Signed-off-by: Kerem Karabay <kekrby@gmail.com>
Signed-off-by: Aditya Garg <gargaditya08@live.com>
Signed-off-by: Jiri Kosina <jkosina@suse.com>
Kill the extra get_uprobe() + put_uprobe() in uprobe_unregister() and
move the possibly final put_uprobe() from delete_uprobe() to its only
caller, uprobe_unregister().
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: "Masami Hiramatsu (Google)" <mhiramat@kernel.org>
Link: https://lore.kernel.org/r/20240801132749.GA8817@redhat.com
Fold __uprobe_unregister() into its single caller, uprobe_unregister().
A separate patch to simplify the next change.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: "Masami Hiramatsu (Google)" <mhiramat@kernel.org>
Link: https://lore.kernel.org/r/20240801132744.GA8814@redhat.com
If register_for_each_vma() fails uprobe_register() can safely drop
uprobe->register_rwsem and use uprobe_unregister(). There is no worry
about the races with another register/unregister, consumer_add() was
already called so this case doesn't differ from _unregister() right
after the successful _register().
Yes this means the extra up_write() + down_write(), but this is the
slow and unlikely case anyway.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: "Masami Hiramatsu (Google)" <mhiramat@kernel.org>
Link: https://lore.kernel.org/r/20240801132739.GA8809@redhat.com
This way uprobe_unregister() and uprobe_apply() can use "struct uprobe *"
rather than inode + offset. This simplifies the code and allows to avoid
the unnecessary find_uprobe() + put_uprobe() in these functions.
TODO: uprobe_unregister() still needs get_uprobe/put_uprobe to ensure that
this uprobe can't be freed before up_write(&uprobe->register_rwsem).
Co-developed-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/r/20240801132734.GA8803@redhat.com
It doesn't make any sense to have 2 versions of _register(). Note that
trace_uprobe_enable(), the only user of uprobe_register(), doesn't need
to check tu->ref_ctr_offset to decide which one should be used, it could
safely pass ref_ctr_offset == 0 to uprobe_register_refctr().
Add this argument to uprobe_register(), update the callers, and kill
uprobe_register_refctr().
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20240801132728.GA8800@redhat.com
get_user_pages_remote() and the comment above it make no sense.
There is no task_struct passed into get_user_pages_remote() anymore, and
nowadays mm_account_fault() increments the current->min/maj_flt counters
regardless of FAULT_FLAG_REMOTE.
Reported-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20240801132714.GA8783@redhat.com
The comment above uprobe_write_opcode() is wrong, unapply_uprobe() calls
it under mmap_read_lock() and this is correct.
And it is completely unclear why register_for_each_vma() takes mmap_lock
for writing, add a comment to explain that mmap_write_lock() is needed to
avoid the following race:
- A task T hits the bp installed by uprobe and calls
find_active_uprobe()
- uprobe_unregister() removes this uprobe/bp
- T calls find_uprobe() which returns NULL
- another uprobe_register() installs the bp at the same address
- T calls is_trap_at_addr() which returns true
- T returns to handle_swbp() and gets SIGTRAP.
Reported-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: "Masami Hiramatsu (Google)" <mhiramat@kernel.org>
Link: https://lore.kernel.org/r/20240801132709.GA8780@redhat.com
When tracing user functions with uprobe functionality, it's common to
install the probe (e.g., a BPF program) at the first instruction of the
function. This is often going to be `push %rbp` instruction in function
preamble, which means that within that function frame pointer hasn't
been established yet. This leads to consistently missing an actual
caller of the traced function, because perf_callchain_user() only
records current IP (capturing traced function) and then following frame
pointer chain (which would be caller's frame, containing the address of
caller's caller).
So when we have target_1 -> target_2 -> target_3 call chain and we are
tracing an entry to target_3, captured stack trace will report
target_1 -> target_3 call chain, which is wrong and confusing.
This patch proposes a x86-64-specific heuristic to detect `push %rbp`
(`push %ebp` on 32-bit architecture) instruction being traced. Given
entire kernel implementation of user space stack trace capturing works
under assumption that user space code was compiled with frame pointer
register (%rbp/%ebp) preservation, it seems pretty reasonable to use
this instruction as a strong indicator that this is the entry to the
function. In that case, return address is still pointed to by %rsp/%esp,
so we fetch it and add to stack trace before proceeding to unwind the
rest using frame pointer-based logic.
We also check for `endbr64` (for 64-bit modes) as another common pattern
for function entry, as suggested by Josh Poimboeuf. Even if we get this
wrong sometimes for uprobes attached not at the function entry, it's OK
because stack trace will still be overall meaningful, just with one
extra bogus entry. If we don't detect this, we end up with guaranteed to
be missing caller function entry in the stack trace, which is worse
overall.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20240729175223.23914-1-andrii@kernel.org
