diff --git a/debian/changelog b/debian/changelog
index 130cef7a2..6dfd5a5c1 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -4,6 +4,7 @@ linux (4.17.6-2) UNRELEASED; urgency=medium
   * debian/control: Fix arch/profile qualifications for libelf-dev
     build-dependency
   * debian/rules.real: Pass KERNEL_ARCH variable down to debian/rules.d
+  * debian/rules.d/tools/perf/Makefile: Use KERNEL_ARCH variable
 
  -- Ben Hutchings <ben@decadent.org.uk>  Thu, 12 Jul 2018 15:16:15 +0100
 
diff --git a/debian/rules.d/tools/perf/Makefile b/debian/rules.d/tools/perf/Makefile
index 40c331fdd..663de7d29 100644
--- a/debian/rules.d/tools/perf/Makefile
+++ b/debian/rules.d/tools/perf/Makefile
@@ -2,37 +2,21 @@ include $(top_rulesdir)/Makefile.inc
 
 ifeq ($(filter nopython,$(DEB_BUILD_PROFILES)),)
 
-DEB_HOST_ARCH_CPU := $(shell dpkg-architecture -qDEB_HOST_ARCH_CPU)
-
-ifeq ($(DEB_HOST_ARCH_CPU),alpha)
-  KERNEL_ARCH_PERF = alpha
-else ifeq ($(DEB_HOST_ARCH_CPU),arm)
-  KERNEL_ARCH_PERF = arm
-else ifeq ($(DEB_HOST_ARCH_CPU),arm64)
-  KERNEL_ARCH_PERF = arm64
-else ifneq ($(filter mips%,$(DEB_HOST_ARCH_CPU)),)
-  KERNEL_ARCH_PERF = mips
-else ifeq ($(DEB_HOST_ARCH_CPU),hppa)
-  KERNEL_ARCH_PERF = parisc
-else ifneq ($(filter powerpc% ppc%,$(DEB_HOST_ARCH_CPU)),)
-  # But pure 32-bit toolchains currently don't work
+ifneq ($(filter alpha arm arm64 mips parisc s390 sh sparc,$(KERNEL_ARCH)),)
+HAVE_PERF := 1
+else ifeq ($(KERNEL_ARCH),powerpc)
+  # Pure 32-bit toolchains currently don't work
   ifneq ($(shell dpkg-architecture -qDEB_HOST_ARCH),powerpcspe)
-    KERNEL_ARCH_PERF = powerpc
+    HAVE_PERF := 1
   endif
-else ifneq ($(filter s390%,$(DEB_HOST_ARCH_CPU)),)
-  KERNEL_ARCH_PERF = s390
-else ifeq ($(DEB_HOST_ARCH_CPU),sh4)
-  KERNEL_ARCH_PERF = sh
-else ifneq ($(filter sparc%,$(DEB_HOST_ARCH_CPU)),)
-  KERNEL_ARCH_PERF = sparc
-else ifneq ($(filter amd64 i386,$(DEB_HOST_ARCH_CPU)),)
-  # But x32 isn't supported yet
+else ifeq ($(KERNEL_ARCH),x86)
+  # x32 isn't supported yet
   ifneq ($(shell dpkg-architecture -qDEB_HOST_ARCH),x32)
-    KERNEL_ARCH_PERF = x86
+    HAVE_PERF := 1
   endif
 endif
 
-MAKE_PERF := $(MAKE) O=$(CURDIR) prefix=/usr V=1 ARCH=$(KERNEL_ARCH_PERF) EXTRA_WARNINGS=-Wno-error EXTRA_CFLAGS='$(CFLAGS) $(CPPFLAGS)' LDFLAGS='$(LDFLAGS)'
+MAKE_PERF := $(MAKE) O=$(CURDIR) prefix=/usr V=1 ARCH=$(KERNEL_ARCH) EXTRA_WARNINGS=-Wno-error EXTRA_CFLAGS='$(CFLAGS) $(CPPFLAGS)' LDFLAGS='$(LDFLAGS)'
 
 # Disable Gtk UI until it's more usable
 MAKE_PERF += NO_GTK2=1
@@ -55,7 +39,7 @@ MAKE_PERF += NO_LIBCRYPTO=1
 MAKE_PERF += LIBBABELTRACE=1
 
 all:
-ifdef KERNEL_ARCH_PERF
+ifdef HAVE_PERF
 # perf changes some default directories depending on whether DESTDIR is
 # set.  We must define it even when building to avoid a rebuild when we
 # run 'make install'.
@@ -71,7 +55,7 @@ endif
 endif
 
 install:
-ifdef KERNEL_ARCH_PERF
+ifdef HAVE_PERF
 	+$(MAKE_PERF) -C $(top_srcdir)/tools/perf -f Makefile.perf install VERSION=$(VERSION)
 # Don't install a 'trace' alias yet:
 # - We need a wrapper for it anyway, so there's little point adding a