pub const USER_MODIFIABLE_RFLAGS: usize = _; // 347_605usizeExpand description
RFLAGS bits that non-privileged code may modify.
This is the union of the flags that Linux allows ptrace and rt_sigreturn
to modify. Because the set allowed by rt_sigreturn is a strict subset of
the ptrace set (it excludes NT), this is effectively the set of flags
that ptrace may modify.
Reference: https://elixir.bootlin.com/linux/v7.1/source/arch/x86/include/asm/sighandling.h#L11-L14.
Reference: https://elixir.bootlin.com/linux/v7.1/source/arch/x86/kernel/ptrace.c#L158-L163.