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diff --git a/docs/about/deprecated.rst b/docs/about/deprecated.rst
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@@ -184,6 +184,25 @@ be an effective use of its limited resources, and thus intends to discontinue
 it. Since all recent x86 hardware from the past >10 years is capable of the
 64-bit x86 extensions, a corresponding 64-bit OS should be used instead.
 
+TCG Plugin support not enabled by default on 32-bit hosts (since 9.2)
+'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
+
+While it is still possible to enable TCG plugin support for 32-bit
+hosts there are a number of potential pitfalls when instrumenting
+64-bit guests. The plugin APIs typically pass most addresses as
+uint64_t but practices like encoding that address in a host pointer
+for passing as user-data will lose data. As most software analysis
+benefits from having plenty of host memory it seems reasonable to
+encourage users to use 64 bit builds of QEMU for analysis work
+whatever targets they are instrumenting.
+
+TCG Plugin support not enabled by default with TCI (since 9.2)
+''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
+
+While the TCG interpreter can interpret the TCG ops used by plugins it
+is going to be so much slower it wouldn't make sense for any serious
+instrumentation. Due to implementation differences there will also be
+anomalies in things like memory instrumentation.
 
 System emulator CPUs
 --------------------