Fire and forget Hyperlink handling to break deadlock #8087
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DHowett
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Over to @PankajBhojwani for another signoff in the morning 😄 |
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@msftbot make sure @PankajBhojwani signs off on this |
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Fire and forget on the hyperlink handler inside the TermControl. ## PR Checklist * [x] Closes #7994 * [x] Tested manually * [x] Hi, I work here. ## Detailed Description of the Pull Request / Additional comments In `TermControl`, `_HyperlinkHandler` is called by `_PointerPressedHandler` which has taken a write lock for all its friends. However, `_HyperlinkHandler` downstreams to `ShellExecute` which can pump the message queue looking for something. That pumping of the queue can trigger messages that also want the write lock to update state. They get stuck. Everything hangs. `_HyperlinkHandler` really only needs read lock and really only for as long as it takes to fill up its parameters before it's invoked... but the simpler and more contained solution is to just fire and forget the rest of the method that causes the deadlock to a continuation at the tail of the dispatcher queue so `_PointerPressedHandler` can complete and naturally drop the write lock. ## Validation Steps Performed - Launched `main` manually on my box and clicked the hyperlink that is detected when Powershell starts and it froze. - Launched this change manually on my box and clicked the hyperlink that is detected when Powershell starts and it did not freeze. (cherry picked from commit 2ea4742)
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Fire and forget on the hyperlink handler inside the TermControl.
PR Checklist
Detailed Description of the Pull Request / Additional comments
In
TermControl,_HyperlinkHandleris called by_PointerPressedHandlerwhich has taken a write lock for all itsfriends. However,
_HyperlinkHandlerdownstreams toShellExecutewhich can pump the message queue looking for something. That pumping of
the queue can trigger messages that also want the write lock to update
state. They get stuck. Everything hangs.
_HyperlinkHandlerreally only needs read lock and really only for aslong as it takes to fill up its parameters before it's invoked... but
the simpler and more contained solution is to just fire and forget the
rest of the method that causes the deadlock to a continuation at the
tail of the dispatcher queue so
_PointerPressedHandlercan completeand naturally drop the write lock.
Validation Steps Performed
mainmanually on my box and clicked the hyperlink that isdetected when Powershell starts and it froze.
is detected when Powershell starts and it did not freeze.