Paul Burton [Thu, 1 Jul 2021 17:24:07 +0000 (10:24 -0700)]
tracing: Resize tgid_map to pid_max, not PID_MAX_DEFAULT
Currently tgid_map is sized at PID_MAX_DEFAULT entries, which means that
on systems where pid_max is configured higher than PID_MAX_DEFAULT the
ftrace record-tgid option doesn't work so well. Any tasks with PIDs
higher than PID_MAX_DEFAULT are simply not recorded in tgid_map, and
don't show up in the saved_tgids file.
In particular since systemd v243 & above configure pid_max to its
highest possible 1<<22 value by default on 64 bit systems this renders
the record-tgids option of little use.
Increase the size of tgid_map to the configured pid_max instead,
allowing it to cover the full range of PIDs up to the maximum value of
PID_MAX_LIMIT if the system is configured that way.
On 64 bit systems with pid_max == PID_MAX_LIMIT this will increase the
size of tgid_map from 256KiB to 16MiB. Whilst this 64x increase in
memory overhead sounds significant 64 bit systems are presumably best
placed to accommodate it, and since tgid_map is only allocated when the
record-tgid option is actually used presumably the user would rather it
spends sufficient memory to actually record the tgids they expect.
The size of tgid_map could also increase for CONFIG_BASE_SMALL=y
configurations, but these seem unlikely to be systems upon which people
are both configuring a large pid_max and running ftrace with record-tgid
anyway.
Of note is that we only allocate tgid_map once, the first time that the
record-tgid option is enabled. Therefore its size is only set once, to
the value of pid_max at the time the record-tgid option is first
enabled. If a user increases pid_max after that point, the saved_tgids
file will not contain entries for any tasks with pids beyond the earlier
value of pid_max.
Link: https://lkml.kernel.org/r/20210701172407.889626-2-paulburton@google.com Fixes: d914ba37d714 ("tracing: Add support for recording tgid of tasks") Cc: Ingo Molnar <mingo@redhat.com> Cc: Joel Fernandes <joelaf@google.com> Cc: <stable@vger.kernel.org> Signed-off-by: Paul Burton <paulburton@google.com>
[ Fixed comment coding style ] Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Paul Burton [Wed, 30 Jun 2021 00:34:05 +0000 (17:34 -0700)]
tracing: Simplify & fix saved_tgids logic
The tgid_map array records a mapping from pid to tgid, where the index
of an entry within the array is the pid & the value stored at that index
is the tgid.
The saved_tgids_next() function iterates over pointers into the tgid_map
array & dereferences the pointers which results in the tgid, but then it
passes that dereferenced value to trace_find_tgid() which treats it as a
pid & does a further lookup within the tgid_map array. It seems likely
that the intent here was to skip over entries in tgid_map for which the
recorded tgid is zero, but instead we end up skipping over entries for
which the thread group leader hasn't yet had its own tgid recorded in
tgid_map.
A minimal fix would be to remove the call to trace_find_tgid, turning:
if (trace_find_tgid(*ptr))
into:
if (*ptr)
..but it seems like this logic can be much simpler if we simply let
seq_read() iterate over the whole tgid_map array & filter out empty
entries by returning SEQ_SKIP from saved_tgids_show(). Here we take that
approach, removing the incorrect logic here entirely.
Link: https://lkml.kernel.org/r/20210630003406.4013668-1-paulburton@google.com Fixes: d914ba37d714 ("tracing: Add support for recording tgid of tasks") Cc: Ingo Molnar <mingo@redhat.com> Cc: Joel Fernandes <joelaf@google.com> Cc: <stable@vger.kernel.org> Signed-off-by: Paul Burton <paulburton@google.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Add semicolons to the __assign_str() uses without semicolon termination
and all the other uses without semicolon termination via additional defines
that are equivalent to __assign_str() with the eventual goal of removing
the semicolon from the __assign_str() macro definition.
Austin Kim [Tue, 29 Jun 2021 14:05:48 +0000 (15:05 +0100)]
tracing: Change variable type as bool for clean-up
The wakeup_rt wakeup_dl, tracing_dl is only set to 0, 1.
So changing type of wakeup_rt wakeup_dl, tracing_dl as bool
makes relevant routine be more readable.
tracepoint: Add tracepoint_probe_register_may_exist() for BPF tracing
All internal use cases for tracepoint_probe_register() is set to not ever
be called with the same function and data. If it is, it is considered a
bug, as that means the accounting of handling tracepoints is corrupted.
If the function and data for a tracepoint is already registered when
tracepoint_probe_register() is called, it will call WARN_ON_ONCE() and
return with EEXISTS.
The BPF system call can end up calling tracepoint_probe_register() with
the same data, which now means that this can trigger the warning because
of a user space process. As WARN_ON_ONCE() should not be called because
user space called a system call with bad data, there needs to be a way to
register a tracepoint without triggering a warning.
Enter tracepoint_probe_register_may_exist(), which can be called, but will
not cause a WARN_ON() if the probe already exists. It will still error out
with EEXIST, which will then be sent to the user space that performed the
BPF system call.
This keeps the previous testing for issues with other users of the
tracepoint code, while letting BPF call it with duplicated data and not
warn about it.
While running osnoise tracer with other tracers that rely on
synchronize_rcu_tasks(), where that just hung.
The reason is that osnoise_main() never schedules out if the interval
is less than 1, and this will cause synchronize_rcu_tasks() to never
return.
Link: https://lkml.kernel.org/r/20210628114953.6dc06a91@oasis.local.home Fixes: bce29ac9ce0bb ("trace: Add osnoise tracer") Acked-by: Paul E. McKenney <paulmck@kernel.org> Reviewed-by: Daniel Bristot de Oliveira <bristot@redhat.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Yun Zhou [Sat, 26 Jun 2021 03:21:56 +0000 (11:21 +0800)]
seq_buf: Make trace_seq_putmem_hex() support data longer than 8
Since the raw memory 'data' does not go forward, it will dump repeated
data if the data length is more than 8. If we want to dump longer data
blocks, we need to repeatedly call macro SEQ_PUT_HEX_FIELD. I think it
is a bit redundant, and multiple function calls also affect the performance.
Yun Zhou [Sat, 26 Jun 2021 03:21:55 +0000 (11:21 +0800)]
seq_buf: Fix overflow in seq_buf_putmem_hex()
There's two variables being increased in that loop (i and j), and i
follows the raw data, and j follows what is being written into the buffer.
We should compare 'i' to MAX_MEMHEX_BYTES or compare 'j' to HEX_CHARS.
Otherwise, if 'j' goes bigger than HEX_CHARS, it will overflow the
destination buffer.
The timerlat tracer aims to help the preemptive kernel developers to
found souces of wakeup latencies of real-time threads. Like cyclictest,
the tracer sets a periodic timer that wakes up a thread. The thread then
computes a *wakeup latency* value as the difference between the *current
time* and the *absolute time* that the timer was set to expire. The main
goal of timerlat is tracing in such a way to help kernel developers.
Usage
Write the ASCII text "timerlat" into the current_tracer file of the
tracing system (generally mounted at /sys/kernel/tracing).
For example:
[root@f32 ~]# cd /sys/kernel/tracing/
[root@f32 tracing]# echo timerlat > current_tracer
It is possible to follow the trace by reading the trace trace file:
The tracer creates a per-cpu kernel thread with real-time priority that
prints two lines at every activation. The first is the *timer latency*
observed at the *hardirq* context before the activation of the thread.
The second is the *timer latency* observed by the thread, which is the
same level that cyclictest reports. The ACTIVATION ID field
serves to relate the *irq* execution to its respective *thread* execution.
The irq/thread splitting is important to clarify at which context
the unexpected high value is coming from. The *irq* context can be
delayed by hardware related actions, such as SMIs, NMIs, IRQs
or by a thread masking interrupts. Once the timer happens, the delay
can also be influenced by blocking caused by threads. For example, by
postponing the scheduler execution via preempt_disable(), by the
scheduler execution, or by masking interrupts. Threads can
also be delayed by the interference from other threads and IRQs.
The timerlat can also take advantage of the osnoise: traceevents.
For example:
In the context of high-performance computing (HPC), the Operating System
Noise (*osnoise*) refers to the interference experienced by an application
due to activities inside the operating system. In the context of Linux,
NMIs, IRQs, SoftIRQs, and any other system thread can cause noise to the
system. Moreover, hardware-related jobs can also cause noise, for example,
via SMIs.
The osnoise tracer leverages the hwlat_detector by running a similar
loop with preemption, SoftIRQs and IRQs enabled, thus allowing all
the sources of *osnoise* during its execution. Using the same approach
of hwlat, osnoise takes note of the entry and exit point of any
source of interferences, increasing a per-cpu interference counter. The
osnoise tracer also saves an interference counter for each source of
interference. The interference counter for NMI, IRQs, SoftIRQs, and
threads is increased anytime the tool observes these interferences' entry
events. When a noise happens without any interference from the operating
system level, the hardware noise counter increases, pointing to a
hardware-related noise. In this way, osnoise can account for any
source of interference. At the end of the period, the osnoise tracer
prints the sum of all noise, the max single noise, the percentage of CPU
available for the thread, and the counters for the noise sources.
Usage
Write the ASCII text "osnoise" into the current_tracer file of the
tracing system (generally mounted at /sys/kernel/tracing).
For example::
[root@f32 ~]# cd /sys/kernel/tracing/
[root@f32 tracing]# echo osnoise > current_tracer
It is possible to follow the trace by reading the trace trace file::
In addition to the regular trace fields (from TASK-PID to TIMESTAMP), the
tracer prints a message at the end of each period for each CPU that is
running an osnoise/CPU thread. The osnoise specific fields report:
- The RUNTIME IN USE reports the amount of time in microseconds that
the osnoise thread kept looping reading the time.
- The NOISE IN US reports the sum of noise in microseconds observed
by the osnoise tracer during the associated runtime.
- The % OF CPU AVAILABLE reports the percentage of CPU available for
the osnoise thread during the runtime window.
- The MAX SINGLE NOISE IN US reports the maximum single noise observed
during the runtime window.
- The Interference counters display how many each of the respective
interference happened during the runtime window.
Note that the example above shows a high number of HW noise samples.
The reason being is that this sample was taken on a virtual machine,
and the host interference is detected as a hardware interference.
Tracer options
The tracer has a set of options inside the osnoise directory, they are:
- osnoise/cpus: CPUs at which a osnoise thread will execute.
- osnoise/period_us: the period of the osnoise thread.
- osnoise/runtime_us: how long an osnoise thread will look for noise.
- osnoise/stop_tracing_us: stop the system tracing if a single noise
higher than the configured value happens. Writing 0 disables this
option.
- osnoise/stop_tracing_total_us: stop the system tracing if total noise
higher than the configured value happens. Writing 0 disables this
option.
- tracing_threshold: the minimum delta between two time() reads to be
considered as noise, in us. When set to 0, the default value will
be used, which is currently 5 us.
Additional Tracing
In addition to the tracer, a set of tracepoints were added to
facilitate the identification of the osnoise source.
- osnoise:sample_threshold: printed anytime a noise is higher than
the configurable tolerance_ns.
- osnoise:nmi_noise: noise from NMI, including the duration.
- osnoise:irq_noise: noise from an IRQ, including the duration.
- osnoise:softirq_noise: noise from a SoftIRQ, including the
duration.
- osnoise:thread_noise: noise from a thread, including the duration.
Note that all the values are *net values*. For example, if while osnoise
is running, another thread preempts the osnoise thread, it will start a
thread_noise duration at the start. Then, an IRQ takes place, preempting
the thread_noise, starting a irq_noise. When the IRQ ends its execution,
it will compute its duration, and this duration will be subtracted from
the thread_noise, in such a way as to avoid the double accounting of the
IRQ execution. This logic is valid for all sources of noise.
Here is one example of the usage of these tracepoints::
In this example, a noise sample of 8 microseconds was reported in the last
line, pointing to two interferences. Looking backward in the trace, the
two previous entries were about the migration thread running after a
timer IRQ execution. The first event is not part of the noise because
it took place one millisecond before.
It is worth noticing that the sum of the duration reported in the
tracepoints is smaller than eight us reported in the sample_threshold.
The reason roots in the overhead of the entry and exit code that happens
before and after any interference execution. This justifies the dual
approach: measuring thread and tracing.
Link: https://lkml.kernel.org/r/e649467042d60e7b62714c9c6751a56299d15119.1624372313.git.bristot@redhat.com Cc: Phil Auld <pauld@redhat.com> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Kate Carcia <kcarcia@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Alexandre Chartre <alexandre.chartre@oracle.com> Cc: Clark Willaims <williams@redhat.com> Cc: John Kacur <jkacur@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: x86@kernel.org Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Daniel Bristot de Oliveira <bristot@redhat.com>
[
Made the following functions static:
trace_irqentry_callback()
trace_irqexit_callback()
trace_intel_irqentry_callback()
trace_intel_irqexit_callback()
Added to include/trace.h:
osnoise_arch_register()
osnoise_arch_unregister()
Fixed define logic for LATENCY_FS_NOTIFY
Reported-by: kernel test robot <lkp@intel.com>
] Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
tracing: Add LATENCY_FS_NOTIFY to define if latency_fsnotify() is defined
With the coming addition of the osnoise tracer, the configs needed to
include the latency_fsnotify() has become more complex, and to keep the
declaration in the header file the same as in the C file, just have the
logic needed to define it in one place, and that defines LATENCY_FS_NOTIFY
which will be used in the C code.
Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Steven Rostedt [Tue, 22 Jun 2021 14:42:26 +0000 (16:42 +0200)]
trace: Add __print_ns_to_secs() and __print_ns_without_secs() helpers
To have nanosecond output displayed in a more human readable format, its
nicer to convert it to a seconds format (XXX.YYYYYYYYY). The problem is that
to do so, the numbers must be divided by NSEC_PER_SEC, and moded too. But as
these numbers are 64 bit, this can not be done simply with '/' and '%'
operators, but must use do_div() instead.
Instead of performing the expensive do_div() in the hot path of the
tracepoint, it is more efficient to perform it during the output phase. But
passing in do_div() can confuse the parser, and do_div() doesn't work
exactly like a normal C function. It modifies the number in place, and we
don't want to modify the actual values in the ring buffer.
Two helper functions are now created:
__print_ns_to_secs() and __print_ns_without_secs()
They both take a value of nanoseconds, and the former will return that
number divided by NSEC_PER_SEC, and the latter will mod it with NSEC_PER_SEC
giving a way to print a nice human readable format:
hwlat has some time operation checks on the sample loop, and it is
currently using pr_err (printk) to report them. The problem is that
this can lead the system to an unresponsible state due to an overflow of
printk messages. This problem can be mitigated by writing the error
message to the trace buffer.
Remove the printk messages from the sampling loop, switching the to
messages in the trace buffer.
No functional change.
Link: https://lkml.kernel.org/r/9d77c34869748aa105e965c769d24642914eea3a.1624372313.git.bristot@redhat.com Cc: Phil Auld <pauld@redhat.com> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Kate Carcia <kcarcia@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Alexandre Chartre <alexandre.chartre@oracle.com> Cc: Clark Willaims <williams@redhat.com> Cc: John Kacur <jkacur@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: x86@kernel.org Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Daniel Bristot de Oliveira <bristot@redhat.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
trace: Add a generic function to read/write u64 values from tracefs
The hwlat detector and (in preparation for) the osnoise/timerlat tracers
have a set of u64 parameters that the user can read/write via tracefs.
For instance, we have hwlat_detector's window and width.
To reduce the code duplication, hwlat's window and width share the same
read function. However, they do not share the write functions because
they do different parameter checks. For instance, the width needs to
be smaller than the window, while the window needs to be larger
than the window. The same pattern repeats on osnoise/timerlat, and
a large portion of the code was devoted to the write function.
Despite having different checks, the write functions have the same
structure:
read a user-space buffer
take the lock that protects the value
check for minimum and maximum acceptable values
save the value
release the lock
return success or error
To reduce the code duplication also in the write functions, this patch
provides a generic read and write implementation for u64 values that
need to be within some minimum and/or maximum parameters, while
(potentially) being protected by a lock.
To use this interface, the structure trace_min_max_param needs to be
filled:
The desired value is stored on the variable pointed by *val. If *min
points to a minimum acceptable value, it will be checked during the
write operation. Likewise, if *max points to a maximum allowable value,
it will be checked during the write operation. Finally, if *lock points
to a mutex, it will be taken at the beginning of the operation and
released at the end.
The definition of a trace_min_max_param needs to passed as the
(private) *data for tracefs_create_file(), and the trace_min_max_fops
(added by this patch) as the *fops file_operations.
Link: https://lkml.kernel.org/r/3e35760a7c8b5c55f16ae5ad5fc54a0e71cbe647.1624372313.git.bristot@redhat.com Cc: Phil Auld <pauld@redhat.com> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Kate Carcia <kcarcia@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Alexandre Chartre <alexandre.chartre@oracle.com> Cc: Clark Willaims <williams@redhat.com> Cc: John Kacur <jkacur@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: x86@kernel.org Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Daniel Bristot de Oliveira <bristot@redhat.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Implements the per-cpu mode in which a sampling thread is created for
each cpu in the "cpus" (and tracing_mask).
The per-cpu mode has the potention to speed up the hwlat detection by
running on multiple CPUs at the same time, at the cost of higher cpu
usage with irqs disabled. Use with care.
[
Changed get_cpu_data() to static. Reported-by: kernel test robot <lkp@intel.com>
]
Link: https://lkml.kernel.org/r/ec06d0ab340e8460d293772faba19ad8a5c371aa.1624372313.git.bristot@redhat.com Cc: Phil Auld <pauld@redhat.com> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Kate Carcia <kcarcia@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Alexandre Chartre <alexandre.chartre@oracle.com> Cc: Clark Willaims <williams@redhat.com> Cc: John Kacur <jkacur@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: x86@kernel.org Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Daniel Bristot de Oliveira <bristot@redhat.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
When in the round-robin mode, if the tracer detects a change in the
hwlatd thread affinity by an external tool, e.g., taskset, the
round-robin logic is disabled. The disable_migrate variable currently
tracks this.
With the addition of the "mode" config and the mode "none," the
disable_migrate logic is equivalent to switch to the "none" mode.
Hence, instead of using a hidden variable to track this behavior,
switch the mode to none, informing the user about this change.
Link: https://lkml.kernel.org/r/a679af672458d6b1f62252605905c5214030f247.1624372313.git.bristot@redhat.com Cc: Phil Auld <pauld@redhat.com> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Kate Carcia <kcarcia@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Alexandre Chartre <alexandre.chartre@oracle.com> Cc: Clark Willaims <williams@redhat.com> Cc: John Kacur <jkacur@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: x86@kernel.org Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Daniel Bristot de Oliveira <bristot@redhat.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Provides the "mode" config to the hardware latency detector. hwlatd has
two different operation modes. The default mode is the "round-robin" one,
in which a single hwlatd thread runs, migrating among the allowed CPUs in a
"round-robin" fashion. This is the current behavior.
The "none" sets the allowed cpumask for a single hwlatd thread at the
startup, but skips the round-robin, letting the scheduler handle the
migration.
In preparation to the per-cpu mode.
Link: https://lkml.kernel.org/r/f3b1271262aa030c680e26615c1b9b2d71e55e92.1624372313.git.bristot@redhat.com Cc: Phil Auld <pauld@redhat.com> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Kate Carcia <kcarcia@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Alexandre Chartre <alexandre.chartre@oracle.com> Cc: Clark Willaims <williams@redhat.com> Cc: John Kacur <jkacur@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: x86@kernel.org Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Daniel Bristot de Oliveira <bristot@redhat.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
bootconfig/tracing/ktest: Add ktest examples of testing bootconfig
bootconfig is a new feature that appends scripts onto the initrd, and the
kernel executes the scripts as an extended kernel command line.
Need to add tests to test that the happened. To test the bootconfig
properly, the initrd needs to be updated and the kernel rebooted. ktest is
the perfect solution to perform these tests.
Add a example bootconfig.conf in the tools/testing/ktest/examples/include
and example bootconfig scripts in tools/testing/ktest/examples/bootconfig
and also include verifier scripts that ktest will install on the target
and run to make sure that the bootconfig options in the scripts took place
after the target rebooted with the new initrd update.
Add a kernel command line option that disables printing of events to
console at late_initcall_sync(). This is useful when needing to see
specific events written to console on boot up, but not wanting it when
user space starts, as user space may make the console so noisy that the
system becomes inoperable.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
tracing: Add better comments for the filtering temp buffer use case
When filtering is enabled, the event is copied into a temp buffer instead
of being written into the ring buffer directly, because the discarding of
events from the ring buffer is very expensive, and doing the extra copy is
much faster than having to discard most of the time.
As that logic is subtle, add comments to explain in more detail to what is
going on and how it works.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
tracing: Simplify the max length test when using the filtering temp buffer
When filtering trace events, a temp buffer is used because the extra copy
from the temp buffer into the ring buffer is still faster than the direct
write into the ring buffer followed by a discard if the filter does not
match.
But the data that can be stored in the temp buffer is a PAGE_SIZE minus the
ring buffer event header. The calculation of that header size is complex,
but using the helper macro "struct_size()" can simplify it.
bootconfig: Support mixing a value and subkeys under a key
Support mixing a value and subkeys under a key. Since kernel cmdline
options will support "aaa.bbb=value1 aaa.bbb.ccc=value2", it is
better that the bootconfig supports such configuration too.
Note that this does not change syntax itself but just accepts
mixed value and subkeys e.g.
key = value1
key.subkey = value2
But this is not accepted;
key {
value1
subkey = value2
}
That will make value1 as a subkey.
Also, the order of the value node under a key is fixed. If there
are a value and subkeys, the value is always the first child node
of the key. Thus if user specifies subkeys first, e.g.
key.subkey = value1
key = value2
In the program (and /proc/bootconfig), it will be shown as below
It is not possible to put an array value with subkeys under
a key node, because both of subkeys and the array elements
are using "next" field of the xbc_node.
Thus this changes the array values to use "child" field in
the array case. The reason why split this change is to
test it easily.
Hyeonggon Yoo [Sat, 29 May 2021 06:14:23 +0000 (15:14 +0900)]
tracing: Add WARN_ON_ONCE when returned value is negative
ret is assigned return value of event_hist_trigger_func, but the value
is unused. It is better to warn when returned value is negative,
rather than just ignoring it.
Jiapeng Chong [Sat, 8 May 2021 10:37:16 +0000 (18:37 +0800)]
tracing: Remove redundant assignment to event_var
Variable event_var is set to 'ERR_PTR(-EINVAL)', but this value
is never read as it is overwritten or not used later on, hence
it is a redundant assignment and can be removed.
Clean up the following clang-analyzer warning:
kernel/trace/trace_events_hist.c:2437:21: warning: Value stored to
'event_var' during its initialization is never read
[clang-analyzer-deadcode.DeadStores].
Ed Tsai [Thu, 22 Apr 2021 12:22:26 +0000 (20:22 +0800)]
sched/tracing: Remove the redundant 'success' in the sched tracepoint
'success' is left here for a long time and also it is meaningless
for the upper user. Just remove it.
[ There were some tools expecting this, and this may break them. But
hopefully they've been fixed in the mean time. Otherwise this may be
likely reverted - SDR ]
James Wang has reproduced it stably on the latest 4.19 LTS.
After some debugging, we finally proved that it's due to ftrace
buffer out-of-bound access using a debug tool as follows:
[ 86.775200] BUG: Out-of-bounds write at addr 0xffff88aefe8b7000
[ 86.780806] no_context+0xdf/0x3c0
[ 86.784327] __do_page_fault+0x252/0x470
[ 86.788367] do_page_fault+0x32/0x140
[ 86.792145] page_fault+0x1e/0x30
[ 86.795576] strncpy_from_unsafe+0x66/0xb0
[ 86.799789] fetch_memory_string+0x25/0x40
[ 86.804002] fetch_deref_string+0x51/0x60
[ 86.808134] kprobe_trace_func+0x32d/0x3a0
[ 86.812347] kprobe_dispatcher+0x45/0x50
[ 86.816385] kprobe_ftrace_handler+0x90/0xf0
[ 86.820779] ftrace_ops_assist_func+0xa1/0x140
[ 86.825340] 0xffffffffc00750bf
[ 86.828603] do_sys_open+0x5/0x1f0
[ 86.832124] do_syscall_64+0x5b/0x1b0
[ 86.835900] entry_SYSCALL_64_after_hwframe+0x44/0xa9
commit b220c049d519 ("tracing: Check length before giving out
the filter buffer") adds length check to protect trace data
overflow introduced in 0fc1b09ff1ff, seems that this fix can't prevent
overflow entirely, the length check should also take the sizeof
entry->array[0] into account, since this array[0] is filled the
length of trace data and occupy addtional space and risk overflow.
Link: https://lkml.kernel.org/r/20210607125734.1770447-1-liangyan.peng@linux.alibaba.com Cc: stable@vger.kernel.org Cc: Ingo Molnar <mingo@redhat.com> Cc: Xunlei Pang <xlpang@linux.alibaba.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Fixes: b220c049d519 ("tracing: Check length before giving out the filter buffer") Reviewed-by: Xunlei Pang <xlpang@linux.alibaba.com> Reviewed-by: yinbinbin <yinbinbin@alibabacloud.com> Reviewed-by: Wetp Zhang <wetp.zy@linux.alibaba.com> Tested-by: James Wang <jnwang@linux.alibaba.com> Signed-off-by: Liangyan <liangyan.peng@linux.alibaba.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
ftrace: Do not blindly read the ip address in ftrace_bug()
It was reported that a bug on arm64 caused a bad ip address to be used for
updating into a nop in ftrace_init(), but the error path (rightfully)
returned -EINVAL and not -EFAULT, as the bug caused more than one error to
occur. But because -EINVAL was returned, the ftrace_bug() tried to report
what was at the location of the ip address, and read it directly. This
caused the machine to panic, as the ip was not pointing to a valid memory
address.
Instead, read the ip address with copy_from_kernel_nofault() to safely
access the memory, and if it faults, report that the address faulted,
otherwise report what was in that location.
Link: https://lore.kernel.org/lkml/20210607032329.28671-1-mark-pk.tsai@mediatek.com/ Cc: stable@vger.kernel.org Fixes: 05736a427f7e1 ("ftrace: warn on failure to disable mcount callers") Reported-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com> Tested-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Linus Torvalds [Sun, 6 Jun 2021 22:39:56 +0000 (15:39 -0700)]
Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI fixes from James Bottomley:
"Five small and fairly minor fixes, all in drivers"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: scsi_devinfo: Add blacklist entry for HPE OPEN-V
scsi: ufs: ufs-mediatek: Fix HCI version in some platforms
scsi: qedf: Do not put host in qedf_vport_create() unconditionally
scsi: lpfc: Fix failure to transmit ABTS on FC link
scsi: target: core: Fix warning on realtime kernels
Linus Torvalds [Sun, 6 Jun 2021 21:24:13 +0000 (14:24 -0700)]
Merge tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
Pull ext4 fixes from Ted Ts'o:
"Miscellaneous ext4 bug fixes"
* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: Only advertise encrypted_casefold when encryption and unicode are enabled
ext4: fix no-key deletion for encrypt+casefold
ext4: fix memory leak in ext4_fill_super
ext4: fix fast commit alignment issues
ext4: fix bug on in ext4_es_cache_extent as ext4_split_extent_at failed
ext4: fix accessing uninit percpu counter variable with fast_commit
ext4: fix memory leak in ext4_mb_init_backend on error path.
Linus Torvalds [Sun, 6 Jun 2021 19:39:36 +0000 (12:39 -0700)]
Merge tag 'powerpc-5.13-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc fixes from Michael Ellerman:
"Fix our KVM reverse map real-mode handling since we enabled huge
vmalloc (in some configurations).
Revert a recent change to our IOMMU code which broke some devices.
Fix KVM handling of FSCR on P7/P8, which could have possibly let a
guest crash it's Qemu.
Fix kprobes validation of prefixed instructions across page boundary.
Thanks to Alexey Kardashevskiy, Christophe Leroy, Fabiano Rosas,
Frederic Barrat, Naveen N. Rao, and Nicholas Piggin"
* tag 'powerpc-5.13-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
Revert "powerpc/kernel/iommu: Align size for IOMMU_PAGE_SIZE() to save TCEs"
KVM: PPC: Book3S HV: Save host FSCR in the P7/8 path
powerpc: Fix reverse map real-mode address lookup with huge vmalloc
powerpc/kprobes: Fix validation of prefixed instructions across page boundary
Linus Torvalds [Sun, 6 Jun 2021 19:25:43 +0000 (12:25 -0700)]
Merge tag 'x86_urgent_for_v5.13-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Borislav Petkov:
"A bunch of x86/urgent stuff accumulated for the last two weeks so
lemme unload it to you.
It should be all totally risk-free, of course. :-)
- Fix out-of-spec hardware (1st gen Hygon) which does not implement
MSR_AMD64_SEV even though the spec clearly states so, and check
CPUID bits first.
- Send only one signal to a task when it is a SEGV_PKUERR si_code
type.
- Do away with all the wankery of reserving X amount of memory in the
first megabyte to prevent BIOS corrupting it and simply and
unconditionally reserve the whole first megabyte.
- Make alternatives NOP optimization work at an arbitrary position
within the patched sequence because the compiler can put
single-byte NOPs for alignment anywhere in the sequence (32-bit
retpoline), vs our previous assumption that the NOPs are only
appended.
- Force-disable ENQCMD[S] instructions support and remove
update_pasid() because of insufficient protection against FPU state
modification in an interrupt context, among other xstate horrors
which are being addressed at the moment. This one limits the
fallout until proper enablement.
- Use cpu_feature_enabled() in the idxd driver so that it can be
build-time disabled through the defines in disabled-features.h.
- Fix LVT thermal setup for SMI delivery mode by making sure the APIC
LVT value is read before APIC initialization so that softlockups
during boot do not happen at least on one machine.
- Mark all legacy interrupts as legacy vectors when the IO-APIC is
disabled and when all legacy interrupts are routed through the PIC"
* tag 'x86_urgent_for_v5.13-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/sev: Check SME/SEV support in CPUID first
x86/fault: Don't send SIGSEGV twice on SEGV_PKUERR
x86/setup: Always reserve the first 1M of RAM
x86/alternative: Optimize single-byte NOPs at an arbitrary position
x86/cpufeatures: Force disable X86_FEATURE_ENQCMD and remove update_pasid()
dmaengine: idxd: Use cpu_feature_enabled()
x86/thermal: Fix LVT thermal setup for SMI delivery mode
x86/apic: Mark _all_ legacy interrupts when IO/APIC is missing
Daniel Rosenberg [Sat, 22 May 2021 00:41:32 +0000 (00:41 +0000)]
ext4: fix no-key deletion for encrypt+casefold
commit 471fbbea7ff7 ("ext4: handle casefolding with encryption") is
missing a few checks for the encryption key which are needed to
support deleting enrypted casefolded files when the key is not
present.
This bug made it impossible to delete encrypted+casefolded directories
without the encryption key, due to errors like:
W : EXT4-fs warning (device vdc): __ext4fs_dirhash:270: inode #49202: comm Binder:378_4: Siphash requires key
Repro steps in kvm-xfstests test appliance:
mkfs.ext4 -F -E encoding=utf8 -O encrypt /dev/vdc
mount /vdc
mkdir /vdc/dir
chattr +F /vdc/dir
keyid=$(head -c 64 /dev/zero | xfs_io -c add_enckey /vdc | awk '{print $NF}')
xfs_io -c "set_encpolicy $keyid" /vdc/dir
for i in `seq 1 100`; do
mkdir /vdc/dir/$i
done
xfs_io -c "rm_enckey $keyid" /vdc
rm -rf /vdc/dir # fails with the bug
Alexey Makhalov [Fri, 21 May 2021 07:55:33 +0000 (07:55 +0000)]
ext4: fix memory leak in ext4_fill_super
Buffer head references must be released before calling kill_bdev();
otherwise the buffer head (and its page referenced by b_data) will not
be freed by kill_bdev, and subsequently that bh will be leaked.
If blocksizes differ, sb_set_blocksize() will kill current buffers and
page cache by using kill_bdev(). And then super block will be reread
again but using correct blocksize this time. sb_set_blocksize() didn't
fully free superblock page and buffer head, and being busy, they were
not freed and instead leaked.
This can easily be reproduced by calling an infinite loop of:
systemctl start <ext4_on_lvm>.mount, and
systemctl stop <ext4_on_lvm>.mount
... since systemd creates a cgroup for each slice which it mounts, and
the bh leak get amplified by a dying memory cgroup that also never
gets freed, and memory consumption is much more easily noticed.
Fixes: ce40733ce93d ("ext4: Check for return value from sb_set_blocksize") Fixes: ac27a0ec112a ("ext4: initial copy of files from ext3") Link: https://lore.kernel.org/r/20210521075533.95732-1-amakhalov@vmware.com Signed-off-by: Alexey Makhalov <amakhalov@vmware.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org
Fast commit recovery data on disk may not be aligned. So, when the
recovery code reads it, this patch makes sure that fast commit info
found on-disk is first memcpy-ed into an aligned variable before
accessing it. As a consequence of it, we also remove some macros that
could resulted in unaligned accesses.
This patch's modification is according to Jan Kara's suggestion in:
https://patchwork.ozlabs.org/project/linux-ext4/patch/20210428085158.3728201-1-yebin10@huawei.com/
"I see. Now I understand your patch. Honestly, seeing how fragile is trying
to fix extent tree after split has failed in the middle, I would probably
go even further and make sure we fix the tree properly in case of ENOSPC
and EDQUOT (those are easily user triggerable). Anything else indicates a
HW problem or fs corruption so I'd rather leave the extent tree as is and
don't try to fix it (which also means we will not create overlapping
extents)."
Linus Torvalds [Sat, 5 Jun 2021 22:45:11 +0000 (15:45 -0700)]
Merge branch 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c fixes from Wolfram Sang:
"Some more bugfixes from I2C for v5.13. Usual stuff"
* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
i2c: qcom-geni: Suspend and resume the bus during SYSTEM_SLEEP_PM ops
i2c: qcom-geni: Add shutdown callback for i2c
i2c: tegra-bpmp: Demote kernel-doc abuses
i2c: altera: Fix formatting issue in struct and demote unworthy kernel-doc headers
Olof Johansson [Sat, 5 Jun 2021 22:43:46 +0000 (15:43 -0700)]
Merge tag 'ti-k3-dt-fixes-for-v5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/nmenon/linux into arm/fixes
Devicetree fixes for TI K3 platforms for v5.13 merge window:
These minor fixes include:
* Fixups for device tree discovered during yaml conversion
* Fixups for missing dma-coherent property in j7200
* Removal of camera sensor node from am65 evm dts to overlay
as camera sensor boards are variable.
* tag 'ti-k3-dt-fixes-for-v5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/nmenon/linux:
arm64: dts: ti: k3*: Introduce reg definition for interrupt routers
arm64: dts: ti: k3-am65|j721e|am64: Map the dma / navigator subsystem via explicit ranges
arm64: dts: ti: k3-*: Rename the TI-SCI node
arm64: dts: ti: k3-am65-wakeup: Drop un-necessary properties from dmsc node
arm64: dts: ti: k3-am65-wakeup: Add debug region to TI-SCI node
arm64: dts: ti: k3-*: Rename the TI-SCI clocks node name
arm64: dts: ti: j7200-main: Mark Main NAVSS as dma-coherent
arm64: dts: ti: k3-am654-base-board: remove ov5640
Olof Johansson [Sat, 5 Jun 2021 22:41:40 +0000 (15:41 -0700)]
Merge tag 'omap-for-v5.13/fixes-pm' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap into arm/fixes
PM and build warning fixes for omaps
While chasing system suspend related regressions, I noticed few other
issues related to PM would be good to have fixed:
- UART idling does not always work for hardware autoidle features
- am335x resume works only the first time unless musb module is loaded
Then there are three patches for omap1 related warnings caused by the gpio
changes, and one build warning fix for legacy mmc platform code when mmc
is built as a loadable module.
These can all be merged whenever suitable naturally. I've sent the more
urgent SATA regression fix separately although it appears in this pull
request too because of the branches merged.
* tag 'omap-for-v5.13/fixes-pm' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap:
ARM: OMAP1: ams-delta: remove unused function ams_delta_camera_power
bus: ti-sysc: Fix flakey idling of uarts and stop using swsup_sidle_act
bus: ti-sysc: Fix am335x resume hang for usb otg module
ARM: OMAP2+: Fix build warning when mmc_omap is not built
ARM: OMAP1: isp1301-omap: Add missing gpiod_add_lookup_table function
ARM: OMAP1: Fix use of possibly uninitialized irq variable
Olof Johansson [Sat, 5 Jun 2021 22:39:22 +0000 (15:39 -0700)]
Merge tag 'amlogic-fixes-v5.13-rc1' of https://git.kernel.org/pub/scm/linux/kernel/git/amlogic/linux into arm/fixes
Amlogic fixes for v5.13-rc1
- arm64: meson: select COMMON_CLK to select a proper implementation of the clock API
- soc: amlogic: meson-clk-measure: remove redundant dev_err call in meson_msr_probe()
* tag 'amlogic-fixes-v5.13-rc1' of https://git.kernel.org/pub/scm/linux/kernel/git/amlogic/linux:
arm64: meson: select COMMON_CLK
soc: amlogic: meson-clk-measure: remove redundant dev_err call in meson_msr_probe()
Olof Johansson [Sat, 5 Jun 2021 22:24:10 +0000 (15:24 -0700)]
Merge tag 'imx-fixes-5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/shawnguo/linux into arm/fixes
i.MX fixes for 5.13:
- Fix missing-prototypes warning of 'imx27_pm_init' in i.MX27 platform
pm code.
- A couple of patches from Fabio Estevam to fix 'tuning-step' property
in imx7d-meerkat96 and imx7d-pico DT.
- Fix '#gpio-cells' of nxp,pca8574 device in imx6qdl-emcon-avari DT.
- A couple of patches from Lucas Stach to fix regulator and voltage for
imx8mq-zii-ultra board.
- Add missing regulators for imx6q-dhcom to avoid possible instability
issues.
- Fix memory-controller settings for fsl-ls1028a DT.
- Fix RGMII clock and voltage for a couple of fsl-ls1028a-kontron-sl28
boards.
- Fix RGMII connection to QCA8334 switch for imx6dl-yapp4 board.
* tag 'imx-fixes-5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/shawnguo/linux:
ARM: dts: imx: emcon-avari: Fix nxp,pca8574 #gpio-cells
ARM: dts: imx7d-pico: Fix the 'tuning-step' property
ARM: dts: imx7d-meerkat96: Fix the 'tuning-step' property
arm64: dts: freescale: sl28: var1: fix RGMII clock and voltage
arm64: dts: freescale: sl28: var4: fix RGMII clock and voltage
ARM: imx: pm-imx27: Include "common.h"
arm64: dts: zii-ultra: fix 12V_MAIN voltage
arm64: dts: zii-ultra: remove second GEN_3V3 regulator instance
arm64: dts: ls1028a: fix memory node
ARM: dts: imx6q-dhcom: Add PU,VDD1P1,VDD2P5 regulators
ARM: dts: imx6dl-yapp4: Fix RGMII connection to QCA8334 switch
Linus Torvalds [Sat, 5 Jun 2021 17:55:41 +0000 (10:55 -0700)]
Merge branch 'akpm' (patches from Andrew)
Merge misc fixes from Andrew Morton:
"13 patches.
Subsystems affected by this patch series: mips, mm (kfence, debug,
pagealloc, memory-hotplug, hugetlb, kasan, and hugetlb), init, proc,
lib, ocfs2, and mailmap"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
mailmap: use private address for Michel Lespinasse
ocfs2: fix data corruption by fallocate
lib: crc64: fix kernel-doc warning
mm, hugetlb: fix simple resv_huge_pages underflow on UFFDIO_COPY
mm/kasan/init.c: fix doc warning
proc: add .gitignore for proc-subset-pid selftest
hugetlb: pass head page to remove_hugetlb_page()
drivers/base/memory: fix trying offlining memory blocks with memory holes on aarch64
mm/page_alloc: fix counting of free pages after take off from buddy
mm/debug_vm_pgtable: fix alignment for pmd/pud_advanced_tests()
pid: take a reference when initializing `cad_pid`
kfence: use TASK_IDLE when awaiting allocation
Revert "MIPS: make userspace mapping young by default"
Linus Torvalds [Sat, 5 Jun 2021 17:45:13 +0000 (10:45 -0700)]
Merge tag 'riscv-for-linus-5.13-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux
Pull RISC-V fixes from Palmer Dabbelt:
- Build with '-mno-relax' when using LLVM's linker, which doesn't
support linker relaxation.
- A fix to build without SiFive's errata.
- A fix to use PAs during init_resources()
- A fix to avoid W+X mappings during boot.
* tag 'riscv-for-linus-5.13-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
RISC-V: Fix memblock_free() usages in init_resources()
riscv: skip errata_cip_453.o if CONFIG_ERRATA_SIFIVE_CIP_453 is disabled
riscv: mm: Fix W+X mappings at boot
riscv: Use -mno-relax when using lld linker
Junxiao Bi [Sat, 5 Jun 2021 03:01:42 +0000 (20:01 -0700)]
ocfs2: fix data corruption by fallocate
When fallocate punches holes out of inode size, if original isize is in
the middle of last cluster, then the part from isize to the end of the
cluster will be zeroed with buffer write, at that time isize is not yet
updated to match the new size, if writeback is kicked in, it will invoke
ocfs2_writepage()->block_write_full_page() where the pages out of inode
size will be dropped. That will cause file corruption. Fix this by
zero out eof blocks when extending the inode size.
Running the following command with qemu-image 4.2.1 can get a corrupted
coverted image file easily.
Link: https://lkml.kernel.org/r/20210528210648.9124-1-junxiao.bi@oracle.com Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com> Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com> Cc: Jan Kara <jack@suse.cz> Cc: Mark Fasheh <mark@fasheh.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Changwei Ge <gechangwei@live.cn> Cc: Gang He <ghe@suse.com> Cc: Jun Piao <piaojun@huawei.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mina Almasry [Sat, 5 Jun 2021 03:01:36 +0000 (20:01 -0700)]
mm, hugetlb: fix simple resv_huge_pages underflow on UFFDIO_COPY
The userfaultfd hugetlb tests cause a resv_huge_pages underflow. This
happens when hugetlb_mcopy_atomic_pte() is called with !is_continue on
an index for which we already have a page in the cache. When this
happens, we allocate a second page, double consuming the reservation,
and then fail to insert the page into the cache and return -EEXIST.
To fix this, we first check if there is a page in the cache which
already consumed the reservation, and return -EEXIST immediately if so.
There is still a rare condition where we fail to copy the page contents
AND race with a call for hugetlb_no_page() for this index and again we
will underflow resv_huge_pages. That is fixed in a more complicated
patch not targeted for -stable.
Test:
Hacked the code locally such that resv_huge_pages underflows produce a
warning, then:
./tools/testing/selftests/vm/userfaultfd hugetlb_shared 10
2 /tmp/kokonut_test/huge/userfaultfd_test && echo test success
./tools/testing/selftests/vm/userfaultfd hugetlb 10
2 /tmp/kokonut_test/huge/userfaultfd_test && echo test success
Both tests succeed and produce no warnings. After the test runs number
of free/resv hugepages is correct.
[mike.kravetz@oracle.com: changelog fixes]
Link: https://lkml.kernel.org/r/20210528004649.85298-1-almasrymina@google.com Fixes: 8fb5debc5fcd ("userfaultfd: hugetlbfs: add hugetlb_mcopy_atomic_pte for userfaultfd support") Signed-off-by: Mina Almasry <almasrymina@google.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Peter Xu <peterx@redhat.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Yu Kuai [Sat, 5 Jun 2021 03:01:33 +0000 (20:01 -0700)]
mm/kasan/init.c: fix doc warning
Fix gcc W=1 warning:
mm/kasan/init.c:228: warning: Function parameter or member 'shadow_start' not described in 'kasan_populate_early_shadow'
mm/kasan/init.c:228: warning: Function parameter or member 'shadow_end' not described in 'kasan_populate_early_shadow'
Naoya Horiguchi [Sat, 5 Jun 2021 03:01:27 +0000 (20:01 -0700)]
hugetlb: pass head page to remove_hugetlb_page()
When memory_failure() or soft_offline_page() is called on a tail page of
some hugetlb page, "BUG: unable to handle page fault" error can be
triggered.
remove_hugetlb_page() dereferences page->lru, so it's assumed that the
page points to a head page, but one of the caller,
dissolve_free_huge_page(), provides remove_hugetlb_page() with 'page'
which could be a tail page. So pass 'head' to it, instead.
Link: https://lkml.kernel.org/r/20210526235257.2769473-1-nao.horiguchi@gmail.com Fixes: 6eb4e88a6d27 ("hugetlb: create remove_hugetlb_page() to separate functionality") Signed-off-by: Naoya Horiguchi <naoya.horiguchi@nec.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Reviewed-by: Muchun Song <songmuchun@bytedance.com> Acked-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Cc: Miaohe Lin <linmiaohe@huawei.com> Cc: Matthew Wilcox <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
drivers/base/memory: fix trying offlining memory blocks with memory holes on aarch64
offline_pages() properly checks for memory holes and bails out.
However, we do a page_zone(pfn_to_page(start_pfn)) before calling
offline_pages() when offlining a memory block.
We should not unconditionally call page_zone(pfn_to_page(start_pfn)) on
aarch64 in offlining code, otherwise we can trigger a BUG when hitting a
memory hole:
If nr_vmemmap_pages is set, we know that we are dealing with hotplugged
memory that doesn't have any holes. So call
page_zone(pfn_to_page(start_pfn)) only when really necessary -- when
nr_vmemmap_pages is set and we actually adjust the present pages.
Link: https://lkml.kernel.org/r/20210526075226.5572-1-david@redhat.com Fixes: a08a2ae34613 ("mm,memory_hotplug: allocate memmap from the added memory range") Signed-off-by: David Hildenbrand <david@redhat.com> Reported-by: Qian Cai (QUIC) <quic_qiancai@quicinc.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Mike Rapoport <rppt@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ding Hui [Sat, 5 Jun 2021 03:01:21 +0000 (20:01 -0700)]
mm/page_alloc: fix counting of free pages after take off from buddy
Recently we found that there is a lot MemFree left in /proc/meminfo
after do a lot of pages soft offline, it's not quite correct.
Before Oscar's rework of soft offline for free pages [1], if we soft
offline free pages, these pages are left in buddy with HWPoison flag,
and NR_FREE_PAGES is not updated immediately. So the difference between
NR_FREE_PAGES and real number of available free pages is also even big
at the beginning.
However, with the workload running, when we catch HWPoison page in any
alloc functions subsequently, we will remove it from buddy, meanwhile
update the NR_FREE_PAGES and try again, so the NR_FREE_PAGES will get
more and more closer to the real number of available free pages.
(regardless of unpoison_memory())
Now, for offline free pages, after a successful call
take_page_off_buddy(), the page is no longer belong to buddy allocator,
and will not be used any more, but we missed accounting NR_FREE_PAGES in
this situation, and there is no chance to be updated later.
Do update in take_page_off_buddy() like rmqueue() does, but avoid double
counting if some one already set_migratetype_isolate() on the page.
[1]: commit 06be6ff3d2ec ("mm,hwpoison: rework soft offline for free pages")
Link: https://lkml.kernel.org/r/20210526075247.11130-1-dinghui@sangfor.com.cn Fixes: 06be6ff3d2ec ("mm,hwpoison: rework soft offline for free pages") Signed-off-by: Ding Hui <dinghui@sangfor.com.cn> Suggested-by: Naoya Horiguchi <naoya.horiguchi@nec.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Acked-by: David Hildenbrand <david@redhat.com> Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Gerald Schaefer [Sat, 5 Jun 2021 03:01:18 +0000 (20:01 -0700)]
mm/debug_vm_pgtable: fix alignment for pmd/pud_advanced_tests()
In pmd/pud_advanced_tests(), the vaddr is aligned up to the next pmd/pud
entry, and so it does not match the given pmdp/pudp and (aligned down)
pfn any more.
For s390, this results in memory corruption, because the IDTE
instruction used e.g. in xxx_get_and_clear() will take the vaddr for
some calculations, in combination with the given pmdp. It will then end
up with a wrong table origin, ending on ...ff8, and some of those
wrongly set low-order bits will also select a wrong pagetable level for
the index addition. IDTE could therefore invalidate (or 0x20) something
outside of the page tables, depending on the wrongly picked index, which
in turn depends on the random vaddr.
As result, we sometimes see "BUG task_struct (Not tainted): Padding
overwritten" on s390, where one 0x5a padding value got overwritten with
0x7a.
Fix this by aligning down, similar to how the pmd/pud_aligned pfns are
calculated.
Mark Rutland [Sat, 5 Jun 2021 03:01:14 +0000 (20:01 -0700)]
pid: take a reference when initializing `cad_pid`
During boot, kernel_init_freeable() initializes `cad_pid` to the init
task's struct pid. Later on, we may change `cad_pid` via a sysctl, and
when this happens proc_do_cad_pid() will increment the refcount on the
new pid via get_pid(), and will decrement the refcount on the old pid
via put_pid(). As we never called get_pid() when we initialized
`cad_pid`, we decrement a reference we never incremented, can therefore
free the init task's struct pid early. As there can be dangling
references to the struct pid, we can later encounter a use-after-free
(e.g. when delivering signals).
This was spotted when fuzzing v5.13-rc3 with Syzkaller, but seems to
have been around since the conversion of `cad_pid` to struct pid in
commit 9ec52099e4b8 ("[PATCH] replace cad_pid by a struct pid") from the
pre-KASAN stone age of v2.6.19.
Fix this by getting a reference to the init task's struct pid when we
assign it to `cad_pid`.
Full KASAN splat below.
==================================================================
BUG: KASAN: use-after-free in ns_of_pid include/linux/pid.h:153 [inline]
BUG: KASAN: use-after-free in task_active_pid_ns+0xc0/0xc8 kernel/pid.c:509
Read of size 4 at addr ffff23794dda0004 by task syz-executor.0/273
Memory state around the buggy address: ffff23794dd9ff00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff23794dd9ff80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff23794dda0000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^ ffff23794dda0080: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ffff23794dda0100: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00
==================================================================
Link: https://lkml.kernel.org/r/20210524172230.38715-1-mark.rutland@arm.com Fixes: 9ec52099e4b8678a ("[PATCH] replace cad_pid by a struct pid") Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Christian Brauner <christian.brauner@ubuntu.com> Cc: Cedric Le Goater <clg@fr.ibm.com> Cc: Christian Brauner <christian@brauner.io> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Kees Cook <keescook@chromium.org Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Paul Mackerras <paulus@samba.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Marco Elver [Sat, 5 Jun 2021 03:01:11 +0000 (20:01 -0700)]
kfence: use TASK_IDLE when awaiting allocation
Since wait_event() uses TASK_UNINTERRUPTIBLE by default, waiting for an
allocation counts towards load. However, for KFENCE, this does not make
any sense, since there is no busy work we're awaiting.
Instead, use TASK_IDLE via wait_event_idle() to not count towards load.
BugLink: https://bugzilla.suse.com/show_bug.cgi?id=1185565 Link: https://lkml.kernel.org/r/20210521083209.3740269-1-elver@google.com Fixes: 407f1d8c1b5f ("kfence: await for allocation using wait_event") Signed-off-by: Marco Elver <elver@google.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Alexander Potapenko <glider@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: David Laight <David.Laight@ACULAB.COM> Cc: Hillf Danton <hdanton@sina.com> Cc: <stable@vger.kernel.org> [5.12+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The MIPS cache flush logic needs to know whether the mapping was already
established to decide how to flush caches. This is done by checking the
valid bit in the PTE. The commit above breaks this logic by setting the
valid in the PTE in new mappings, which causes kernel crashes.
Link: https://lkml.kernel.org/r/20210526094335.92948-1-tsbogend@alpha.franken.de Fixes: f685a533a7f ("MIPS: make userspace mapping young by default") Reported-by: Zhou Yanjie <zhouyanjie@wanyeetech.com> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Huang Pei <huangpei@loongson.cn> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linus Torvalds [Sat, 5 Jun 2021 01:25:39 +0000 (18:25 -0700)]
Merge tag 'net-5.13-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from Jakub Kicinski:
"Networking fixes, including fixes from bpf, wireless, netfilter and
wireguard trees.
The bpf vs lockdown+audit fix is the most notable.
Things haven't slowed down just yet, both in terms of regressions in
current release and largish fixes for older code, but we usually see a
slowdown only after -rc5.
Current release - regressions:
- virtio-net: fix page faults and crashes when XDP is enabled
- mlx5e: fix HW timestamping with CQE compression, and make sure they
are only allowed to coexist with capable devices
- stmmac:
- fix kernel panic due to NULL pointer dereference of
mdio_bus_data
- fix double clk unprepare when no PHY device is connected
Current release - new code bugs:
- mt76: a few fixes for the recent MT7921 devices and runtime power
management
Previous releases - regressions:
- ice:
- track AF_XDP ZC enabled queues in bitmap to fix copy mode Tx
- fix allowing VF to request more/less queues via virtchnl
- correct supported and advertised autoneg by using PHY
capabilities
- allow all LLDP packets from PF to Tx
- kbuild: quote OBJCOPY var to avoid a pahole call break the build
- mt76: address the recent FragAttack vulnerabilities not covered by
generic fixes
- ipv6: fix KASAN: slab-out-of-bounds Read in
fib6_nh_flush_exceptions
- Bluetooth:
- fix the erroneous flush_work() order, to avoid double free
- use correct lock to prevent UAF of hdev object
- nfc: fix NULL ptr dereference in llcp_sock_getname() after failed
connect
- ieee802154: multiple fixes to error checking and return values
- igb: fix XDP with PTP enabled
- intel: add correct exception tracing for XDP
- tls: fix use-after-free when TLS offload device goes down and back
up
- ipvs: ignore IP_VS_SVC_F_HASHED flag when adding service
- netfilter: nft_ct: skip expectations for confirmed conntrack
- mptcp: fix falling back to TCP in presence of out of order packets
early in connection lifetime
- wireguard: switch from O(n) to a O(1) algorithm for maintaining
peers, fixing stalls and a large memory leak in the process
Misc:
- devlink: correct VIRTUAL port to not have phys_port attributes
- Bluetooth: fix VIRTIO_ID_BT assigned number
- net: return the correct errno code ENOBUF -> ENOMEM
- wireguard:
- peer: allocate in kmem_cache saving 25% on peer memory
- do not use -O3"
* tag 'net-5.13-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (91 commits)
cxgb4: avoid link re-train during TC-MQPRIO configuration
sch_htb: fix refcount leak in htb_parent_to_leaf_offload
wireguard: allowedips: free empty intermediate nodes when removing single node
wireguard: allowedips: allocate nodes in kmem_cache
wireguard: allowedips: remove nodes in O(1)
wireguard: allowedips: initialize list head in selftest
wireguard: peer: allocate in kmem_cache
wireguard: use synchronize_net rather than synchronize_rcu
wireguard: do not use -O3
wireguard: selftests: make sure rp_filter is disabled on vethc
wireguard: selftests: remove old conntrack kconfig value
virtchnl: Add missing padding to virtchnl_proto_hdrs
ice: Allow all LLDP packets from PF to Tx
ice: report supported and advertised autoneg using PHY capabilities
ice: handle the VF VSI rebuild failure
ice: Fix VFR issues for AVF drivers that expect ATQLEN cleared
ice: Fix allowing VF to request more/less queues via virtchnl
virtio-net: fix for skb_over_panic inside big mode
ipv6: Fix KASAN: slab-out-of-bounds Read in fib6_nh_flush_exceptions
fib: Return the correct errno code
...
Linus Torvalds [Sat, 5 Jun 2021 01:15:33 +0000 (18:15 -0700)]
Merge tag 'perf-tools-fixes-for-v5.13-2021-06-04' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux
Pull perf tools fixes from Arnaldo Carvalho de Melo:
- Fix NULL pointer dereference in 'perf probe' when handling
DW_AT_const_value when looking for a variable, which is valid.
- Fix for capability querying of perf_event_attr.cgroup support in
older kernels.
- Add missing cloning of evsel->use_config_name.
- Honor event config name on --no-merge in 'perf stat'.
- Fix some memory leaks found using ASAN.
- Fix the perf entry for perf_event_attr setup with make LIBPFM4=1 on
s390 z/VM.
- Update MIPS UAPI perf_regs.h file.
- Fix 'perf stat' BPF counter load return check.
* tag 'perf-tools-fixes-for-v5.13-2021-06-04' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux:
perf env: Fix memory leak of bpf_prog_info_linear member
perf symbol-elf: Fix memory leak by freeing sdt_note.args
perf stat: Honor event config name on --no-merge
perf evsel: Add missing cloning of evsel->use_config_name
perf test: Test 17 fails with make LIBPFM4=1 on s390 z/VM
perf stat: Fix error return code in bperf__load()
perf record: Move probing cgroup sampling support
perf probe: Fix NULL pointer dereference in convert_variable_location()
perf tools: Copy uapi/asm/perf_regs.h from the kernel for MIPS
Linus Torvalds [Fri, 4 Jun 2021 22:19:45 +0000 (15:19 -0700)]
Merge tag 'pci-v5.13-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci
Pull PCI fixes from Bjorn Helgaas:
- Fix MSIs for platforms with "msi-map" device-tree property, which we
broke in v5.13-rc1 (Jean-Philippe Brucker)
- Add Krzysztof Wilczyński as PCI reviewer (Lorenzo Pieralisi)
* tag 'pci-v5.13-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
PCI/MSI: Fix MSIs for generic hosts that use device-tree's "msi-map"
MAINTAINERS: Add Krzysztof as PCI host/endpoint controllers reviewer
cxgb4: avoid link re-train during TC-MQPRIO configuration
When configuring TC-MQPRIO offload, only turn off netdev carrier and
don't bring physical link down in hardware. Otherwise, when the
physical link is brought up again after configuration, it gets
re-trained and stalls ongoing traffic.
Also, when firmware is no longer accessible or crashed, avoid sending
FLOWC and waiting for reply that will never come.
Fix following hung_task_timeout_secs trace seen in these cases.
Fixes: b1396c2bd675 ("cxgb4: parse and configure TC-MQPRIO offload") Signed-off-by: Rahul Lakkireddy <rahul.lakkireddy@chelsio.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Yunjian Wang [Fri, 4 Jun 2021 11:03:18 +0000 (19:03 +0800)]
sch_htb: fix refcount leak in htb_parent_to_leaf_offload
The commit ae81feb7338c ("sch_htb: fix null pointer dereference
on a null new_q") fixes a NULL pointer dereference bug, but it
is not correct.
Because htb_graft_helper properly handles the case when new_q
is NULL, and after the previous patch by skipping this call
which creates an inconsistency : dev_queue->qdisc will still
point to the old qdisc, but cl->parent->leaf.q will point to
the new one (which will be noop_qdisc, because new_q was NULL).
The code is based on an assumption that these two pointers are
the same, so it can lead to refcount leaks.
The correct fix is to add a NULL pointer check to protect
qdisc_refcount_inc inside htb_parent_to_leaf_offload.
Fixes: ae81feb7338c ("sch_htb: fix null pointer dereference on a null new_q") Signed-off-by: Yunjian Wang <wangyunjian@huawei.com> Suggested-by: Maxim Mikityanskiy <maximmi@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller [Fri, 4 Jun 2021 21:25:14 +0000 (14:25 -0700)]
Merge branch 'wireguard-fixes'
Jason A. Donenfeld says:
====================
wireguard fixes for 5.13-rc5
Here are bug fixes to WireGuard for 5.13-rc5:
1-2,6) These are small, trivial tweaks to our test harness.
3) Linus thinks -O3 is still dangerous to enable. The code gen wasn't so
much different with -O2 either.
4) We were accidentally calling synchronize_rcu instead of
synchronize_net while holding the rtnl_lock, resulting in some rather
large stalls that hit production machines.
5) Peer allocation was wasting literally hundreds of megabytes on real
world deployments, due to oddly sized large objects not fitting
nicely into a kmalloc slab.
7-9) We move from an insanely expensive O(n) algorithm to a fast O(1)
algorithm, and cleanup a massive memory leak in the process, in
which allowed ips churn would leave danging nodes hanging around
without cleanup until the interface was removed. The O(1) algorithm
eliminates packet stalls and high latency issues, in addition to
bringing operations that took as much as 10 minutes down to less
than a second.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
wireguard: allowedips: free empty intermediate nodes when removing single node
When removing single nodes, it's possible that that node's parent is an
empty intermediate node, in which case, it too should be removed.
Otherwise the trie fills up and never is fully emptied, leading to
gradual memory leaks over time for tries that are modified often. There
was originally code to do this, but was removed during refactoring in
2016 and never reworked. Now that we have proper parent pointers from
the previous commits, we can implement this properly.
In order to reduce branching and expensive comparisons, we want to keep
the double pointer for parent assignment (which lets us easily chain up
to the root), but we still need to actually get the parent's base
address. So encode the bit number into the last two bits of the pointer,
and pack and unpack it as needed. This is a little bit clumsy but is the
fastest and less memory wasteful of the compromises. Note that we align
the root struct here to a minimum of 4, because it's embedded into a
larger struct, and we're relying on having the bottom two bits for our
flag, which would only be 16-bit aligned on m68k.
The existing macro-based helpers were a bit unwieldy for adding the bit
packing to, so this commit replaces them with safer and clearer ordinary
functions.
We add a test to the randomized/fuzzer part of the selftests, to free
the randomized tries by-peer, refuzz it, and repeat, until it's supposed
to be empty, and then then see if that actually resulted in the whole
thing being emptied. That combined with kmemcheck should hopefully make
sure this commit is doing what it should. Along the way this resulted in
various other cleanups of the tests and fixes for recent graphviz.
Fixes: e7096c131e51 ("net: WireGuard secure network tunnel") Cc: stable@vger.kernel.org Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: David S. Miller <davem@davemloft.net>
wireguard: allowedips: allocate nodes in kmem_cache
The previous commit moved from O(n) to O(1) for removal, but in the
process introduced an additional pointer member to a struct that
increased the size from 60 to 68 bytes, putting nodes in the 128-byte
slab. With deployed systems having as many as 2 million nodes, this
represents a significant doubling in memory usage (128 MiB -> 256 MiB).
Fix this by using our own kmem_cache, that's sized exactly right. This
also makes wireguard's memory usage more transparent in tools like
slabtop and /proc/slabinfo.
Fixes: e7096c131e51 ("net: WireGuard secure network tunnel") Suggested-by: Arnd Bergmann <arnd@arndb.de> Suggested-by: Matthew Wilcox <willy@infradead.org> Cc: stable@vger.kernel.org Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Previously, deleting peers would require traversing the entire trie in
order to rebalance nodes and safely free them. This meant that removing
1000 peers from a trie with a half million nodes would take an extremely
long time, during which we're holding the rtnl lock. Large-scale users
were reporting 200ms latencies added to the networking stack as a whole
every time their userspace software would queue up significant removals.
That's a serious situation.
This commit fixes that by maintaining a double pointer to the parent's
bit pointer for each node, and then using the already existing node list
belonging to each peer to go directly to the node, fix up its pointers,
and free it with RCU. This means removal is O(1) instead of O(n), and we
don't use gobs of stack.
The removal algorithm has the same downside as the code that it fixes:
it won't collapse needlessly long runs of fillers. We can enhance that
in the future if it ever becomes a problem. This commit documents that
limitation with a TODO comment in code, a small but meaningful
improvement over the prior situation.
Currently the biggest flaw, which the next commit addresses, is that
because this increases the node size on 64-bit machines from 60 bytes to
68 bytes. 60 rounds up to 64, but 68 rounds up to 128. So we wind up
using twice as much memory per node, because of power-of-two
allocations, which is a big bummer. We'll need to figure something out
there.
Fixes: e7096c131e51 ("net: WireGuard secure network tunnel") Cc: stable@vger.kernel.org Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: David S. Miller <davem@davemloft.net>
wireguard: allowedips: initialize list head in selftest
The randomized trie tests weren't initializing the dummy peer list head,
resulting in a NULL pointer dereference when used. Fix this by
initializing it in the randomized trie test, just like we do for the
static unit test.
While we're at it, all of the other strings like this have the word
"self-test", so add it to the missing place here.
Fixes: e7096c131e51 ("net: WireGuard secure network tunnel") Cc: stable@vger.kernel.org Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: David S. Miller <davem@davemloft.net>
With deployments having upwards of 600k peers now, this somewhat heavy
structure could benefit from more fine-grained allocations.
Specifically, instead of using a 2048-byte slab for a 1544-byte object,
we can now use 1544-byte objects directly, thus saving almost 25%
per-peer, or with 600k peers, that's a savings of 303 MiB. This also
makes wireguard's memory usage more transparent in tools like slabtop
and /proc/slabinfo.
Fixes: 8b5553ace83c ("wireguard: queueing: get rid of per-peer ring buffers") Suggested-by: Arnd Bergmann <arnd@arndb.de> Suggested-by: Matthew Wilcox <willy@infradead.org> Cc: stable@vger.kernel.org Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: David S. Miller <davem@davemloft.net>
wireguard: use synchronize_net rather than synchronize_rcu
Many of the synchronization points are sometimes called under the rtnl
lock, which means we should use synchronize_net rather than
synchronize_rcu. Under the hood, this expands to using the expedited
flavor of function in the event that rtnl is held, in order to not stall
other concurrent changes.
This fixes some very, very long delays when removing multiple peers at
once, which would cause some operations to take several minutes.
Fixes: e7096c131e51 ("net: WireGuard secure network tunnel") Cc: stable@vger.kernel.org Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Apparently, various versions of gcc have O3-related miscompiles. Looking
at the difference between -O2 and -O3 for gcc 11 doesn't indicate
miscompiles, but the difference also doesn't seem so significant for
performance that it's worth risking.
projects / mirror_ubuntu-kernels.git / log