WOW64: Lock the JIT context and block suspend during context operations #5199
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Prevent suspension when flushing thread state to the WOW64 context during BTCpuSetContext as suspension itself performs a flush. If suspension were to occur halfway through FlushThreadStateContext then the fact that the WOW64 context has been dirtied would be missed and the new context would be partially overwritten with stale data from the FEX thread state. Additionally if the context were to be dirtied by suspension at any point during context merging in BTCpuSetContext the input context could be lost. Fixes occasional crashes when starting AC4.
Sonicadvance1
approved these changes
Jan 5, 2026
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Prevent suspension when flushing thread state to the WOW64 context during BTCpuSetContext as suspension itself performs a flush. If suspension were to occur halfway through FlushThreadStateContext then the fact that the WOW64 context has been dirtied would be missed and the new context would be partially overwritten with stale data from the FEX thread state. Additionally if the context were to be dirtied by suspension at any point during context merging in BTCpuSetContext the input context could be lost.
Fixes occasional crashes when starting AC4.