diff --git a/pkgs/os-specific/linux/kernel/linux-testing.nix b/pkgs/os-specific/linux/kernel/linux-testing.nix
index 54e37e7213039c..3fe9ff8e287097 100644
--- a/pkgs/os-specific/linux/kernel/linux-testing.nix
+++ b/pkgs/os-specific/linux/kernel/linux-testing.nix
@@ -1,13 +1,13 @@
-{ stdenv, hostPlatform, fetchurl, perl, buildLinux, ... } @ args:
+{ stdenv, hostPlatform, fetchurl, perl, buildLinux, libelf, utillinux, ... } @ args:
 
 import ./generic.nix (args // rec {
-  version = "4.14-rc8";
-  modDirVersion = "4.14.0-rc8";
-  extraMeta.branch = "4.14";
+  version = "4.15-rc1";
+  modDirVersion = "4.15.0-rc1";
+  extraMeta.branch = "4.15";
 
   src = fetchurl {
     url = "https://git.kernel.org/torvalds/t/linux-${version}.tar.gz";
-    sha256 = "0ir2ggflm1xjnn1kvv2c99m5zni5kg0ygzlpm588wnhkzd93nqjh";
+    sha256 = "1l7c132qb5qjd80hga03ivssfq65brqyd95sb4rd065dqrixp20n";
   };
 
   # Should the testing kernels ever be built on Hydra?
diff --git a/pkgs/os-specific/linux/kernel/manual-config.nix b/pkgs/os-specific/linux/kernel/manual-config.nix
index b0735e94619df2..6a82d2bf8f6dc0 100644
--- a/pkgs/os-specific/linux/kernel/manual-config.nix
+++ b/pkgs/os-specific/linux/kernel/manual-config.nix
@@ -1,4 +1,6 @@
 { runCommand, nettools, bc, perl, gmp, libmpc, mpfr, kmod, openssl
+, libelf ? null
+, utillinux ? null
 , writeTextFile, ubootTools
 , hostPlatform
 }:
@@ -230,13 +232,18 @@ let
     };
 in
 
+assert stdenv.lib.versionAtLeast version "4.15" -> libelf != null;
+assert stdenv.lib.versionAtLeast version "4.15" -> utillinux != null;
 stdenv.mkDerivation ((drvAttrs config stdenv.platform (kernelPatches ++ nativeKernelPatches) configfile) // {
   name = "linux-${version}";
 
   enableParallelBuilding = true;
 
   nativeBuildInputs = [ perl bc nettools openssl gmp libmpc mpfr ]
-    ++ optional (stdenv.platform.kernelTarget == "uImage") ubootTools;
+      ++ optional (stdenv.platform.kernelTarget == "uImage") ubootTools
+      ++ optional (stdenv.lib.versionAtLeast version "4.15") libelf 
+      ++ optional (stdenv.lib.versionAtLeast version "4.15") utillinux
+      ;
 
   hardeningDisable = [ "bindnow" "format" "fortify" "stackprotector" "pic" ];
 
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index eaf9d64d72a183..9205c1cc3be494 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -12577,7 +12577,6 @@ with pkgs;
   linux_testing = callPackage ../os-specific/linux/kernel/linux-testing.nix {
     kernelPatches = [
       kernelPatches.bridge_stp_helper
-      kernelPatches.p9_fixes
       kernelPatches.modinst_arg_list_too_long
     ] ++ lib.optionals ((platform.kernelArch or null) == "mips") [
       kernelPatches.mips_fpureg_emu