Re: List iterator assignment fails, assert iterator not dereferencable

"Igor Tandetnik" <>
Mon, 8 Oct 2007 07:58:58 -0400
"David Bilsby" <> wrote in message

This all works fine up to the point I benchmarked 4 DMA channels from
4 threads. I carefully protected the low level classes list access,
both read and write, with a mutex to prevent multiple threads
updating the list together and from some debugging output to stderr I
am confident that this is valid.

Nevertheless, look for race conditions in your code. For example:

// Store iterator away in higher level class for channel.
m_phUserDMABufHandles[m_numUserDMABufHandles] = hLockedBufHandle;

Those two lines are running under a critical section or a mutex, right?
Because otherwise you can easily end up with an uninitialized iterator
in the array.
With best wishes,
    Igor Tandetnik

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