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On 9/19/19 11:12 AM, Conor McCarthy wrote:<br>
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cite="mid:CAOua6-8qdBw5P7swoKB0+19Feyg4bW0isG1EijfgHFWQezuUmA@mail.gmail.com">
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<div dir="ltr" class="gmail_attr">On Fri, Sep 20, 2019 at 1:32
AM Derek Lesho <<a href="mailto:dlesho@codeweavers.com"
moz-do-not-send="true">dlesho@codeweavers.com</a>>
wrote:<br>
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<blockquote class="gmail_quote" style="margin:0px 0px 0px
0.8ex;border-left:1px solid
rgb(204,204,204);padding-left:1ex">Also, in your patch, I
noticed that you intentionally unlock before <br>
performing the copy or overwrite. This puzzles me, if one
thread waits <br>
on the global mutex for access to a descriptor's view to
dereference, <br>
and we unlock the mutex for them when the view is NULL, they
may crash <br>
when trying to decrement the reference of the NULL view.<br>
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<div>Yes, it's missing a null check after locking the mutex.
If it's null after locking then the function can return
because it means another thread has destroyed the
descriptor. I think the only remaining problem is the old
one of a single mutex being used for all descriptors. Maybe
performance can be improved.<br>
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Even if one thread destroys a descriptor, and then we let both
concurrently write their data, we will leak the Vulkan handle of
written by the thread which writes it to the descriptor first and
gets overwritten.<br>
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