[PATCH 4.14 10/44] ARCv2: [plat-hsdk]: Save accl reg pair by default

From: Greg Kroah-Hartman
Date: Mon Jul 23 2018 - 08:28:44 EST


4.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Vineet Gupta <vgupta@xxxxxxxxxxxx>

commit af1fc5baa724c63ce1733dfcf855bad5ef6078e3 upstream.

This manifsted as strace segfaulting on HSDK because gcc was targetting
the accumulator registers as GPRs, which kernek was not saving/restoring
by default.

Cc: stable@xxxxxxxxxxxxxxx #4.14+
Signed-off-by: Vineet Gupta <vgupta@xxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
arch/arc/Kconfig | 2 +-
arch/arc/plat-hsdk/Kconfig | 2 ++
2 files changed, 3 insertions(+), 1 deletion(-)

--- a/arch/arc/Kconfig
+++ b/arch/arc/Kconfig
@@ -408,7 +408,7 @@ config ARC_HAS_DIV_REM

config ARC_HAS_ACCL_REGS
bool "Reg Pair ACCL:ACCH (FPU and/or MPY > 6)"
- default n
+ default y
help
Depending on the configuration, CPU can contain accumulator reg-pair
(also referred to as r58:r59). These can also be used by gcc as GPR so
--- a/arch/arc/plat-hsdk/Kconfig
+++ b/arch/arc/plat-hsdk/Kconfig
@@ -7,5 +7,7 @@

menuconfig ARC_SOC_HSDK
bool "ARC HS Development Kit SOC"
+ depends on ISA_ARCV2
+ select ARC_HAS_ACCL_REGS
select CLK_HSDK
select RESET_HSDK