book: mention consistency between guest max memory and VM memory config (#1531)

closes INT-3561

Author: jonathanpwang

book/src/advanced-usage/sdk.md

@@ -31,6 +31,10 @@ The `SdkVmConfig` struct allows you to specify the extensions and system configu
 {{ #include ../../../crates/sdk/examples/sdk_app.rs:vm_config }}
 ```
 
+> ℹ️
+> When using Rust to write the guest program, the VM system configuration should keep the default value `pointer_max_bits = 29` to match the hardcoded memory limit of the memory allocator. Otherwise, the guest program may fail due to out of bounds memory access in the VM.
+
+
 ## Running a Program
 
 To run your program and see the public value output, you can do the following:

book/src/writing-apps/write-program.md

@@ -27,7 +27,7 @@ For debugging purposes, `openvm::io::print` and `openvm::io::println` can be use
 
 > ⚠️ **WARNING**
 >
-> The maximum memory address for an OpenVM program is `2^29`. Majority of that (approximately 480-500 MB depending on transpilation) is available to the guest program, but large reads may exceed the maximum memory and thus fail.
+> The maximum memory address for an OpenVM program is `2^29`. The majority of that (approximately 480-500 MB depending on transpilation) is available to the guest program, but large reads may exceed the maximum memory and thus fail.
 
 ## Rust `std` library support