On 7/30/23 23:41, Xin Li wrote:
+
+static DEFINE_FRED_HANDLER(fred_sw_interrupt_user)
+{
+ /*
+ * In compat mode INT $0x80 (32bit system call) is
+ * performance-critical. Handle it first.
+ */
+ if (IS_ENABLED(CONFIG_IA32_EMULATION) &&
+ likely(regs->vector == IA32_SYSCALL_VECTOR)) {
+ regs->orig_ax = regs->ax;
+ regs->ax = -ENOSYS;
+ return do_int80_syscall_32(regs);
+ }
We can presumably drop the early out here as well...
+
+ /*
+ * Some software exceptions can also be triggered as
+ * int instructions, for historical reasons.
+ */
+ switch (regs->vector) {
+ case X86_TRAP_BP:
+ case X86_TRAP_OF:
+ fred_emulate_trap(regs);
+ break;
+ default:
+ regs->vector = X86_TRAP_GP;
+ fred_emulate_fault(regs);
+ break;
+ }
+}
+
