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Kernel: Enforce that Thread::unblock_from_mutex() doesn't happen in IRQ

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Mutexes are not usable from IRQ handlers, so unblock_from_mutex()
can simply VERIFY() that the current processor is not in an IRQ.
This commit is contained in:
Andreas Kling 2022-01-30 12:16:14 +01:00
parent b0e5406ae2
commit 09f0843716
1 changed files with 14 additions and 27 deletions
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41
Kernel/Thread.cpp
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@ -331,36 +331,23 @@ void Thread::block(Kernel::Mutex& lock, SpinlockLocker<Spinlock>& lock_lock, u32
u32 Thread::unblock_from_mutex(Kernel::Mutex& mutex)
{
SpinlockLocker scheduler_lock(g_scheduler_lock);
SpinlockLocker block_lock(m_block_lock);
VERIFY(m_blocking_mutex == &mutex);
auto requested_count = m_lock_requested_count;
block_lock.unlock();
auto do_unblock = [&]() {
SpinlockLocker scheduler_lock(g_scheduler_lock);
SpinlockLocker block_lock(m_block_lock);
VERIFY(m_blocking_mutex == &mutex);
VERIFY(!Processor::current_in_irq());
VERIFY(g_scheduler_lock.is_locked_by_current_processor());
VERIFY(m_block_lock.is_locked_by_current_processor());
VERIFY(m_blocking_mutex == &mutex);
dbgln_if(THREAD_DEBUG, "Thread {} unblocked from Mutex {}", *this, &mutex);
m_blocking_mutex = nullptr;
if (Thread::current() == this) {
set_state(Thread::State::Running);
return;
}
VERIFY(m_state != Thread::State::Runnable && m_state != Thread::State::Running);
set_state(Thread::State::Runnable);
};
if (Processor::current_in_irq() != 0) {
Processor::deferred_call_queue([do_unblock = move(do_unblock), self = make_weak_ptr()]() {
if (auto this_thread = self.strong_ref())
do_unblock();
});
} else {
do_unblock();
VERIFY(!Processor::current_in_irq());
VERIFY(m_blocking_mutex == &mutex);
dbgln_if(THREAD_DEBUG, "Thread {} unblocked from Mutex {}", *this, &mutex);
auto requested_count = m_lock_requested_count;
m_blocking_mutex = nullptr;
if (Thread::current() == this) {
set_state(Thread::State::Running);
return requested_count;
}
VERIFY(m_state != Thread::State::Runnable && m_state != Thread::State::Running);
set_state(Thread::State::Runnable);
return requested_count;
}