<feed xmlns='http://www.w3.org/2005/Atom'>
<title>user/sven/linux.git/include/linux/irqflags.h, branch v5.8.11</title>
<subtitle>Linux Kernel
</subtitle>
<id>https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v5.8.11</id>
<link rel='self' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v5.8.11'/>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/'/>
<updated>2020-06-11T13:15:24Z</updated>
<entry>
<title>x86/entry: Rename trace_hardirqs_off_prepare()</title>
<updated>2020-06-11T13:15:24Z</updated>
<author>
<name>Peter Zijlstra</name>
<email>peterz@infradead.org</email>
</author>
<published>2020-05-29T21:27:40Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=bf2b3008440072068580c609d79a079656af0588'/>
<id>urn:sha1:bf2b3008440072068580c609d79a079656af0588</id>
<content type='text'>
The typical pattern for trace_hardirqs_off_prepare() is:

  ENTRY
    lockdep_hardirqs_off(); // because hardware
    ... do entry magic
    instrumentation_begin();
    trace_hardirqs_off_prepare();
    ... do actual work
    trace_hardirqs_on_prepare();
    lockdep_hardirqs_on_prepare();
    instrumentation_end();
    ... do exit magic
    lockdep_hardirqs_on();

which shows that it's named wrong, rename it to
trace_hardirqs_off_finish(), as it concludes the hardirq_off transition.

Also, given that the above is the only correct order, make the traditional
all-in-one trace_hardirqs_off() follow suit.

Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Link: https://lkml.kernel.org/r/20200529213321.415774872@infradead.org



</content>
</entry>
<entry>
<title>lockdep: Prepare for noinstr sections</title>
<updated>2020-05-19T13:47:21Z</updated>
<author>
<name>Peter Zijlstra</name>
<email>peterz@infradead.org</email>
</author>
<published>2020-03-18T13:22:03Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=c86e9b987cea3dd0209203e714553a47f5d7c6dd'/>
<id>urn:sha1:c86e9b987cea3dd0209203e714553a47f5d7c6dd</id>
<content type='text'>
Force inlining and prevent instrumentation of all sorts by marking the
functions which are invoked from low level entry code with 'noinstr'.

Split the irqflags tracking into two parts. One which does the heavy
lifting while RCU is watching and the final one which can be invoked after
RCU is turned off.

Signed-off-by: Peter Zijlstra &lt;peterz@infradead.org&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Reviewed-by: Alexandre Chartre &lt;alexandre.chartre@oracle.com&gt;
Link: https://lkml.kernel.org/r/20200505134100.484532537@linutronix.de


</content>
</entry>
<entry>
<title>tracing: Provide lockdep less trace_hardirqs_on/off() variants</title>
<updated>2020-05-19T13:47:21Z</updated>
<author>
<name>Thomas Gleixner</name>
<email>tglx@linutronix.de</email>
</author>
<published>2020-03-04T12:09:50Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=0995a5dfbe49badff78e78761fb66f46579f2f9a'/>
<id>urn:sha1:0995a5dfbe49badff78e78761fb66f46579f2f9a</id>
<content type='text'>
trace_hardirqs_on/off() is only partially safe vs. RCU idle. The tracer
core itself is safe, but the resulting tracepoints can be utilized by
e.g. BPF which is unsafe.

Provide variants which do not contain the lockdep invocation so the lockdep
and tracer invocations can be split at the call site and placed
properly. This is required because lockdep needs to be aware of the state
before switching away from RCU idle and after switching to RCU idle because
these transitions can take locks.

As these code pathes are going to be non-instrumentable the tracer can be
invoked after RCU is turned on and before the switch to RCU idle. So for
these new variants there is no need to invoke the rcuidle aware tracer
functions.

Name them so they match the lockdep counterparts.

Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Reviewed-by: Alexandre Chartre &lt;alexandre.chartre@oracle.com&gt;
Acked-by: Peter Zijlstra &lt;peterz@infradead.org&gt;
Link: https://lkml.kernel.org/r/20200505134100.270771162@linutronix.de


</content>
</entry>
<entry>
<title>hrtimer: Don't dereference the hrtimer pointer after the callback</title>
<updated>2020-04-01T11:20:14Z</updated>
<author>
<name>Sebastian Andrzej Siewior</name>
<email>bigeasy@linutronix.de</email>
</author>
<published>2020-03-31T20:18:49Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=73d20564e0dcae003e0d79977f044d5e57496304'/>
<id>urn:sha1:73d20564e0dcae003e0d79977f044d5e57496304</id>
<content type='text'>
A hrtimer can be released in its callback, but lockdep_hrtimer_exit()
dereferences the pointer after the callback returns, i.e. a potential use
after free.

Retrieve the context in which the hrtimer expires before the callback is
invoked and use it in lockdep_hrtimer_exit().

Fixes: 40db173965c0 ("lockdep: Add hrtimer context tracing bits")
Reported-by: syzbot+62c155c276e580cfb606@syzkaller.appspotmail.com
Signed-off-by: Sebastian Andrzej Siewior &lt;bigeasy@linutronix.de&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Link: https://lkml.kernel.org/r/20200331201849.fkp2siy3vcdqvqlz@linutronix.de
</content>
</entry>
<entry>
<title>Merge tag 'x86-entry-2020-03-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2020-03-31T02:14:28Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2020-03-31T02:14:28Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=d5f744f9a2ac9ca6d5baf72e97ce6dc4c2f19fe4'/>
<id>urn:sha1:d5f744f9a2ac9ca6d5baf72e97ce6dc4c2f19fe4</id>
<content type='text'>
Pull x86 entry code updates from Thomas Gleixner:

 - Convert the 32bit syscalls to be pt_regs based which removes the
   requirement to push all 6 potential arguments onto the stack and
   consolidates the interface with the 64bit variant

 - The first small portion of the exception and syscall related entry
   code consolidation which aims to address the recently discovered
   issues vs. RCU, int3, NMI and some other exceptions which can
   interrupt any context. The bulk of the changes is still work in
   progress and aimed for 5.8.

 - A few lockdep namespace cleanups which have been applied into this
   branch to keep the prerequisites for the ongoing work confined.

* tag 'x86-entry-2020-03-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (35 commits)
  x86/entry: Fix build error x86 with !CONFIG_POSIX_TIMERS
  lockdep: Rename trace_{hard,soft}{irq_context,irqs_enabled}()
  lockdep: Rename trace_softirqs_{on,off}()
  lockdep: Rename trace_hardirq_{enter,exit}()
  x86/entry: Rename ___preempt_schedule
  x86: Remove unneeded includes
  x86/entry: Drop asmlinkage from syscalls
  x86/entry/32: Enable pt_regs based syscalls
  x86/entry/32: Use IA32-specific wrappers for syscalls taking 64-bit arguments
  x86/entry/32: Rename 32-bit specific syscalls
  x86/entry/32: Clean up syscall_32.tbl
  x86/entry: Remove ABI prefixes from functions in syscall tables
  x86/entry/64: Add __SYSCALL_COMMON()
  x86/entry: Remove syscall qualifier support
  x86/entry/64: Remove ptregs qualifier from syscall table
  x86/entry: Move max syscall number calculation to syscallhdr.sh
  x86/entry/64: Split X32 syscall table into its own file
  x86/entry/64: Move sys_ni_syscall stub to common.c
  x86/entry/64: Use syscall wrappers for x32_rt_sigreturn
  x86/entry: Refactor SYS_NI macros
  ...
</content>
</entry>
<entry>
<title>lockdep: Rename trace_{hard,soft}{irq_context,irqs_enabled}()</title>
<updated>2020-03-21T15:03:54Z</updated>
<author>
<name>Peter Zijlstra</name>
<email>peterz@infradead.org</email>
</author>
<published>2020-03-20T11:56:42Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=ef996916e78e03d25e56c2d372e5e21fdb471882'/>
<id>urn:sha1:ef996916e78e03d25e56c2d372e5e21fdb471882</id>
<content type='text'>
Continue what commit:

  d820ac4c2fa8 ("locking: rename trace_softirq_[enter|exit] =&gt; lockdep_softirq_[enter|exit]")

started, rename these to avoid confusing them with tracepoints.

git grep -l "trace_\(soft\|hard\)\(irq_context\|irqs_enabled\)" | while read file;
do
	sed -ie 's/trace_\(soft\|hard\)\(irq_context\|irqs_enabled\)/lockdep_\1\2/g' $file;
done

Reported-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Reviewed-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Acked-by: Will Deacon &lt;will@kernel.org&gt;
Link: https://lkml.kernel.org/r/20200320115859.178626842@infradead.org

</content>
</entry>
<entry>
<title>lockdep: Rename trace_softirqs_{on,off}()</title>
<updated>2020-03-21T15:03:54Z</updated>
<author>
<name>Peter Zijlstra</name>
<email>peterz@infradead.org</email>
</author>
<published>2020-03-20T11:56:41Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=0d38453c85b426e47375346812d2271680c47988'/>
<id>urn:sha1:0d38453c85b426e47375346812d2271680c47988</id>
<content type='text'>
Continue what commit:

  d820ac4c2fa8 ("locking: rename trace_softirq_[enter|exit] =&gt; lockdep_softirq_[enter|exit]")

started, rename these to avoid confusing them with tracepoints.

git grep -l "trace_softirqs_\(on\|off\)" | while read file;
do
	sed -ie 's/trace_softirqs_\(on\|off\)/lockdep_softirqs_\1/g' $file;
done

Reported-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Reviewed-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Acked-by: Will Deacon &lt;will@kernel.org&gt;
Link: https://lkml.kernel.org/r/20200320115859.119434738@infradead.org

</content>
</entry>
<entry>
<title>lockdep: Rename trace_hardirq_{enter,exit}()</title>
<updated>2020-03-21T15:03:53Z</updated>
<author>
<name>Thomas Gleixner</name>
<email>tglx@linutronix.de</email>
</author>
<published>2020-03-20T11:56:40Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=2502ec37a7b228b34c1e2e89480f98b92f53046a'/>
<id>urn:sha1:2502ec37a7b228b34c1e2e89480f98b92f53046a</id>
<content type='text'>
Continue what commit:

  d820ac4c2fa8 ("locking: rename trace_softirq_[enter|exit] =&gt; lockdep_softirq_[enter|exit]")

started, rename these to avoid confusing them with tracepoints.

Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Reviewed-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Acked-by: Will Deacon &lt;will@kernel.org&gt;
Link: https://lkml.kernel.org/r/20200320115859.060481361@infradead.org

</content>
</entry>
<entry>
<title>lockdep: Add posixtimer context tracing bits</title>
<updated>2020-03-21T15:00:25Z</updated>
<author>
<name>Sebastian Andrzej Siewior</name>
<email>bigeasy@linutronix.de</email>
</author>
<published>2020-03-21T11:26:04Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=d53f2b62fcb63f6547c10d8c62bca19e957b0eef'/>
<id>urn:sha1:d53f2b62fcb63f6547c10d8c62bca19e957b0eef</id>
<content type='text'>
Splitting run_posix_cpu_timers() into two parts is work in progress which
is stuck on other entry code related problems. The heavy lifting which
involves locking of sighand lock will be moved into task context so the
necessary execution time is burdened on the task and not on interrupt
context.

Until this work completes lockdep with the spinlock nesting rules enabled
would emit warnings for this known context.

Prevent it by setting "-&gt;irq_config = 1" for the invocation of
run_posix_cpu_timers() so lockdep does not complain when sighand lock is
acquried. This will be removed once the split is completed.

Signed-off-by: Sebastian Andrzej Siewior &lt;bigeasy@linutronix.de&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Link: https://lkml.kernel.org/r/20200321113242.751182723@linutronix.de
</content>
</entry>
<entry>
<title>lockdep: Annotate irq_work</title>
<updated>2020-03-21T15:00:24Z</updated>
<author>
<name>Sebastian Andrzej Siewior</name>
<email>bigeasy@linutronix.de</email>
</author>
<published>2020-03-21T11:26:03Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=49915ac35ca7b07c54295a72d905be5064afb89e'/>
<id>urn:sha1:49915ac35ca7b07c54295a72d905be5064afb89e</id>
<content type='text'>
Mark irq_work items with IRQ_WORK_HARD_IRQ which should be invoked in
hardirq context even on PREEMPT_RT. IRQ_WORK without this flag will be
invoked in softirq context on PREEMPT_RT.

Set -&gt;irq_config to 1 for the IRQ_WORK items which are invoked in softirq
context so lockdep knows that these can safely acquire a spinlock_t.

Signed-off-by: Sebastian Andrzej Siewior &lt;bigeasy@linutronix.de&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Link: https://lkml.kernel.org/r/20200321113242.643576700@linutronix.de
</content>
</entry>
</feed>
