Enter restricted mode
#include <zircon/syscalls-next.h> zx_status_t zx_restricted_enter(uint32_t options, uintptr_t vector_table_ptr, uintptr_t context);
Enters restricted mode from normal thread state. If successful, the current thread will return to normal mode via an entry point passed in vector_table_ptr.
vector_table_ptr must be within the current user address space. context may be any value. It is used as a value to pass back to normal mode when returning from restricted mode.
options is a bit vector that contains zero more of the following:
- ZX_RESTRICTED_OPT_EXCEPTION_CHANNEL indicates that any exceptions
encountered while in restricted mode should be delivered using exception
channels. If this option is not present then any exceptions not handled by a
process debugger will cause control to vector to
vector_table_ptrin normal mode with the reason code set to
Arguments to the function at vector_table_ptr are architecturally specific:
On x64, context is placed in rdi and a reason code is placed in rsi. All other registers are currently undefined, including the stack pointer.
On arm64, context is placed in x0 and a reason code is placed in x1. All other registers are currently undefined, including the stack pointer.
On riscv64, context is placed in a0 and a reason code is placed in a1. All other registers are currently undefined, including the stack pointer.
The reason code specifies the reason that normal mode execution has resumed.
This reason code may be one of
Processes created with the
ZX_PROCESS_SHARED option, or via
have two distinct address spaces. One is shared between multiple processes, while the other
is restricted to the specific process. When a thread that is entering restrcited mode
belongs to such a process, the active address space for the thread is updated as follows:
- When entering restricted mode the active address space for the thread is set to the restricted address space of the process.
- When exiting restricted mode the active address space for the thread is set to the shared address space of the process.
No return value on success, since the current thread indirectly returns via vector_table_ptr. In the event of failure, a negative error value is returned.
ZX_ERR_INVALID_ARGS vector_table_ptr is not a valid user address or options is non-zero.
ZX_ERR_BAD_STATE restricted mode register state is invalid.
ZX_RESTRICTED_OPT_EXCEPTION_CHANNEL is not provided and
vectored exceptions are not implemented for the current architecture.