diff --git a/pkgs/os-specific/linux/kernel/common-config.nix b/pkgs/os-specific/linux/kernel/common-config.nix
index 1e9f2cb6a65..62dd7caadbf 100644
--- a/pkgs/os-specific/linux/kernel/common-config.nix
+++ b/pkgs/os-specific/linux/kernel/common-config.nix
@@ -42,6 +42,12 @@ with stdenv.lib;
   SCHEDSTATS n
   DETECT_HUNG_TASK y
 
+  # Bump the maximum number of CPUs to support systems like EC2 x1.*
+  # instances and Xeon Phi.
+  ${optionalString (stdenv.system == "x86_64-linux") ''
+    NR_CPUS 384
+  ''}
+
   # Unix domain sockets.
   UNIX y