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system call instruction

The special instruction that switches the processor into kernel mode to make a system call: syscall on x86-64, svc on ARM64, ecall on RISC-V.

A system call instruction traps to the kernel's system call entry: x86-64 syscall (return address saved in rcx, flags in r11), ARM64 svc #0 on Linux (svc #0x80 on macOS), RISC-V ecall.

Examples

  • x86-64 uses syscall, ARM64 svc #0 and RISC-V ecall.

See also

system call kernel mode call instruction return address
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