Allow guest to specify syscall vector to use.
(Based on Ron Minnich's LGUEST_PLAN9_SYSCALL patch).
This patch allows Guests to specify what system call vector they want,
and we try to reserve it. We only allow one non-Linux system call
vector, to try to avoid DoS on the Host.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
diff --git a/include/linux/lguest.h b/include/linux/lguest.h
index 9ddac2f..0830522 100644
--- a/include/linux/lguest.h
+++ b/include/linux/lguest.h
@@ -48,6 +48,9 @@
/* Fields initialized by the Guest at boot: */
/* Instruction range to suppress interrupts even if enabled */
unsigned long noirq_start, noirq_end;
+
+ /* The vector to try to use for system calls (0x40 or 0x80). */
+ unsigned int syscall_vec;
};
extern struct lguest_data lguest_data;
#endif /* __ASSEMBLY__ */