diff --git a/petsc.spec b/petsc.spec
index a96aa9c..a0d9e63 100644
--- a/petsc.spec
+++ b/petsc.spec
@@ -40,7 +40,18 @@
 %bcond_without openmpi
 %endif
 
+## BLAS
+# openblas available on these architectures.
+%if 0%{?fedora} && 0%{?fedora} > 26
+%{!?openblas_arches:%global openblas_arches x86_64 %{ix86} armv7hl %{power64} aarch64 s390x}
+%else
+%{!?openblas_arches:%global openblas_arches x86_64 %{ix86} armv7hl %{power64} aarch64}
+%endif
+%if 0%{?rhel}
+%{!?openblas_arches:%global openblas_arches x86_64 %{ix86} armv7hl %{power64} aarch64}
+%endif
 %bcond_without blas
+##
 
 #
 ## PETSC looks incompatible with serial MUMPS
@@ -110,7 +121,7 @@
 Name:    petsc
 Summary: Portable Extensible Toolkit for Scientific Computation
 Version: 3.8.0
-Release: 1%{?dist}
+Release: 2%{?dist}
 License: BSD
 URL:     https://www.mcs.anl.gov/petsc
 Source0: http://ftp.mcs.anl.gov/pub/petsc/release-snapshots/petsc-%{version}.tar.gz
@@ -125,7 +136,7 @@ Patch1:  %{name}-lib64.patch
 Patch3:  %{name}-disable_petscnagupgrade.patch
 
 %if %{with superlu}
-BuildRequires: SuperLU-devel
+BuildRequires: SuperLU-devel >= 5.2.0
 %endif
 %if %{with superlumt}
 BuildRequires: SuperLUMT-devel
@@ -140,11 +151,11 @@ BuildRequires: MUMPS-devel
 BuildRequires: suitesparse-devel
 %endif
 %if %{with blas}
-%ifnarch x86_64 %{ix86} armv7hl %{power64} aarch64
+%ifarch %{openblas_arches}
+BuildRequires: openblas-devel, openblas-srpm-macros
+%else
 BuildRequires: blas-devel
 BuildRequires: lapack-devel
-%else
-BuildRequires: openblas-devel
 %endif
 %endif
 BuildRequires: gcc-c++
@@ -183,12 +194,12 @@ PDF and HTML documentation files.
 %if %{with arch64}
 %package -n petsc64
 Summary: Portable Extensible Toolkit for Scientific Computation (64bit INTEGER)
-%ifnarch x86_64 %{ix86} armv7hl %{power64} aarch64
-BuildRequires: blas64-devel
-BuildRequires: lapack64-devel
-%else
+%ifarch %{openblas_arches}
 BuildRequires: openblas-serial64 >= 0.2.19-1
 BuildRequires: openblas-devel >= 0.2.19-1
+%else
+BuildRequires: blas64-devel
+BuildRequires: lapack64-devel
 %endif
 
 %description -n petsc64
@@ -248,11 +259,11 @@ BuildRequires: fftw-openmpi-devel
 BuildRequires: hypre-openmpi-devel
 %endif
 %if %{with blas}
-%ifnarch x86_64 %{ix86} armv7hl %{power64} aarch64
+%ifarch %{openblas_arches}
+BuildRequires: openblas-devel, openblas-srpm-macros
+%else
 BuildRequires: blas-devel
 BuildRequires: lapack-devel
-%else
-BuildRequires: openblas-devel
 %endif
 %endif
 
@@ -306,11 +317,11 @@ BuildRequires: fftw-devel
 BuildRequires: fftw-mpich-devel
 %endif
 %if %{with blas}
-%ifnarch x86_64 %{ix86} armv7hl %{power64} aarch64
+%ifarch %{openblas_arches}
+BuildRequires: openblas-devel, openblas-srpm-macros
+%else
 BuildRequires: blas-devel
 BuildRequires: lapack-devel
-%else
-BuildRequires: openblas-devel
 %endif
 %endif
 
@@ -403,7 +414,7 @@ CFLAGS="$CFLAGS -O3 -Wl,-z,now" CXXFLAGS="$CXXFLAGS -O3" FFLAGS="$FFLAGS -O3 -Wl
  --with-debugging=0 \
 %endif
 %if %{with blas}
-%ifnarch x86_64 %{ix86} armv7hl %{power64} aarch64
+%ifnarch %{openblas_arches}
  --with-blas-lib=-lblas \
  --with-lapack-lib=-llapack \
  --known-64-bit-blas-indices=0 \
@@ -483,7 +494,7 @@ CFLAGS="$CFLAGS -O3 -Wl,-z,now" CXXFLAGS="$CXXFLAGS -O3" FFLAGS="$FFLAGS -O3 -Wl
  --with-debugging=0 \
 %endif
 %if %{with blas64}
-%ifnarch x86_64 %{ix86} armv7hl %{power64} aarch64
+%ifnarch %{openblas_arches}
  --with-blas-lib="-lblas64_" \
  --with-lapack-lib="-llapack64_" \
  --known-64-bit-blas-indices=1 \
@@ -543,7 +554,7 @@ CFLAGS="$CFLAGS -O3 -Wl,-z,now" CXXFLAGS="$CXXFLAGS -O3" FFLAGS="$FFLAGS -O3 -Wl
  --with-debugging=0 \
 %endif
 %if %{with blas}
-%ifnarch x86_64 %{ix86} armv7hl %{power64} aarch64
+%ifnarch %{openblas_arches}
  --with-blas-lib="-lblas" \
  --with-lapack-lib="-llapack" \
  --known-64-bit-blas-indices=0 \
@@ -654,7 +665,7 @@ CFLAGS="$CFLAGS -O3 -Wl,-z,now" CXXFLAGS="$CXXFLAGS -O3" FFLAGS="$FFLAGS -O3 -Wl
  --with-debugging=0 \
 %endif
 %if %{with blas}
-%ifnarch x86_64 %{ix86} armv7hl %{power64} aarch64
+%ifnarch %{openblas_arches}
  --with-blas-lib=-lblas \
  --with-lapack-lib=-llapack \
  --known-64-bit-blas-indices=0 \
@@ -1009,6 +1020,9 @@ make -C buildmpich_dir test
 %endif
 
 %changelog
+* Sun Oct 29 2017 Antonio Trande <sagitter@fedoraproject.org> - 3.8.0-2
+- Define openblas arches
+
 * Tue Oct 03 2017 Antonio Trande <sagitter@fedoraproject.org> - 3.8.0-1
 - Update to 3.8.0
 - with-mpiuni-fortran-binding option deprecated