MIPS: Require O32 FP64 support for MIPS64 with O32 compat

commit 4e9d324d4288b082497c30bc55b8ad13acc7cf01 upstream.

MIPS32r6 code requires FP64 (ie. FR=1) support. Building a kernel with
support for MIPS32r6 binaries but without support for O32 with FP64 is
therefore a problem which can lead to incorrectly executed userland.

CONFIG_MIPS_O32_FP64_SUPPORT is already selected when the kernel is
configured for MIPS32r6, but not when the kernel is configured for
MIPS64r6 with O32 compat support. Select CONFIG_MIPS_O32_FP64_SUPPORT in
such configurations to prevent building kernels which execute MIPS32r6
userland incorrectly.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Matthew Fortune <matthew.fortune@imgtec.com>
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/10674/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index f501665..a3b1ffe 100644 (file)
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -1417,6 +1417,7 @@ config CPU_MIPS64_R6
        select CPU_SUPPORTS_HIGHMEM
        select CPU_SUPPORTS_MSA
        select GENERIC_CSUM
+       select MIPS_O32_FP64_SUPPORT if MIPS32_O32
        help
          Choose this option to build a kernel for release 6 or later of the
          MIPS64 architecture.  New MIPS processors, starting with the Warrior