--- a/src/syscall/mod.rs
+++ b/src/syscall/mod.rs
@@ -28,6 +28,11 @@
     sync::CleanLockToken,
 };
 
+/// Local syscall numbers not yet in the redox_syscall crate.
+/// These are allocated from the 987+ range to avoid collisions with crate numbers.
+pub const SYS_SCHED_SETAFFINITY: usize = 987;
+pub const SYS_SCHED_GETAFFINITY: usize = 988;
+
 /// Debug
 pub mod debug;
 
@@ -220,6 +225,10 @@
                 unlinkat(fd, UserSlice::ro(c, d)?, e, f as _, g as _, token).map(|()| 0)
             }
             SYS_YIELD => sched_yield(token).map(|()| 0),
+
+            // P17-3: CPU affinity syscalls. Numbers allocated locally (not yet in redox_syscall crate).
+            SYS_SCHED_SETAFFINITY => sched_setaffinity(b, UserSlice::ro(c, d)?, token),
+            SYS_SCHED_GETAFFINITY => sched_getaffinity(b, UserSlice::wo(c, d)?, token),
             SYS_NANOSLEEP => nanosleep(
                 UserSlice::ro(b, size_of::<TimeSpec>())?,
                 UserSlice::wo(c, size_of::<TimeSpec>())?.none_if_null(),