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@ -30,6 +30,13 @@ On x86, all available instructions are: `in` `out` `syscall` `sysenter` `cpuid`.
If you are still using Unicorn1, please upgrade to Unicorn2 for better support.
## Memory hooks get called multiple times for a single instruction
There are several possibilities, e.g.:
- The instruction might access memory multiple times like `rep stos` in x86.
- The address to access is bad-aligned and thus the MMU emulation will split the access into several aligned memory access. In worst cases on some arch, it leads to byte by byte access.
## I can't recover from unmapped read/write even I return `true` in the hook, why?
This is a minor change in memory hooks behavior between Unicorn1 and Unicorn2. To gracefully recover from memory read/write error, you have to map the invalid memory before you return true.
@ -38,9 +45,11 @@ It is due to the fact that, if users return `true` without memory mapping set up
See the [sample](https://github.com/unicorn-engine/unicorn/blob/c05fbb7e63aed0b60fc2888e08beceb17bce8ac4/samples/sample_x86.c#L1379-L1393) for details.
## My MIPS emulation gets weird read/write error and CPU exceptions.
## My emulation gets weird read/write error and CPU exceptions.
Note you might have an address that falls in MIPS `kseg` segments. In that case, MMU is bypassed and you have to make sure the corresponding physical memory is mapped. See [#217](https://github.com/unicorn-engine/unicorn/issues/217), [#1371](https://github.com/unicorn-engine/unicorn/issues/1371), [#1550](https://github.com/unicorn-engine/unicorn/issues/1371).
For MIPS, you might have an address that falls in MIPS `kseg` segments. In that case, MMU is bypassed and you have to make sure the corresponding physical memory is mapped. See [#217](https://github.com/unicorn-engine/unicorn/issues/217), [#1371](https://github.com/unicorn-engine/unicorn/issues/1371), [#1550](https://github.com/unicorn-engine/unicorn/issues/1371).
For ARM, you might have an address that falls in some non-executable segments. For example, for m-class ARM cpu, some memory area is not executable according to [the ARM document](https://developer.arm.com/documentation/ddi0403/d/System-Level-Architecture/System-Address-Map/The-system-address-map?lang=en).
## KeyboardInterrupt is not raised during `uc.emu_start`