time: fix deadlock between schedule_wake() and the std alarm thread - #6721
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leftger wants to merge 2 commits into
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time: fix deadlock between schedule_wake() and the std alarm thread#6721leftger wants to merge 2 commits into
leftger wants to merge 2 commits into
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Drop the critical_section::with() wrappers on the std driver; the queue Mutex already provides the necessary synchronization.
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Summary
Fixes a deadlock in the
stdtime driver (embassy-time/src/driver_std.rs) betweenTimeDriver::schedule_wake()andalarm_thread().schedule_wake(): locks the queueMutexfirst, then enters the critical section.alarm_thread(): enters the critical section first, then locks the queueMutex.Fix
Don't use the
critical_section::with()wrappers aroundnext_expiration()in bothschedule_wake()andalarm_thread()