From 4c97a0c8fee302fe64feed21e6f7ed25e3e651b8 Mon Sep 17 00:00:00 2001 From: Babu Moger Date: Fri, 8 Sep 2017 16:14:22 -0700 Subject: [PATCH] arch: define CPU_BIG_ENDIAN for all fixed big endian archs Patch series "Define CPU_BIG_ENDIAN or warn for inconsistencies", v3. While working on enabling queued rwlock on SPARC, found this following code in include/asm-generic/qrwlock.h which uses CONFIG_CPU_BIG_ENDIAN to clear a byte. static inline u8 *__qrwlock_write_byte(struct qrwlock *lock) { return (u8 *)lock + 3 * IS_BUILTIN(CONFIG_CPU_BIG_ENDIAN); } Problem is many of the fixed big endian architectures don't define CPU_BIG_ENDIAN and clears the wrong byte. Define CPU_BIG_ENDIAN for all the fixed big endian architecture to fix it. Also found few more references of this config parameter in drivers/of/base.c drivers/of/fdt.c drivers/tty/serial/earlycon.c drivers/tty/serial/serial_core.c Be aware that this may cause regressions if someone has worked-around problems in the above code already. Remove the work-around. Here is our original discussion https://lkml.org/lkml/2017/5/24/620 Link: http://lkml.kernel.org/r/1499358861-179979-2-git-send-email-babu.moger@oracle.com Signed-off-by: Babu Moger Suggested-by: Arnd Bergmann Acked-by: Geert Uytterhoeven Acked-by: David S. Miller Acked-by: Stafford Horne Cc: Yoshinori Sato Cc: Jonas Bonn Cc: Stefan Kristiansson Cc: "James E.J. Bottomley" Cc: Helge Deller Cc: Alexander Viro Cc: Michal Simek Cc: Michael Ellerman (powerpc) Cc: Peter Zijlstra Cc: Ingo Molnar Cc: Max Filippov Cc: Greg KH Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/frv/Kconfig | 3 +++ arch/h8300/Kconfig | 3 +++ arch/m68k/Kconfig | 3 +++ arch/openrisc/Kconfig | 3 +++ arch/parisc/Kconfig | 3 +++ arch/sparc/Kconfig | 3 +++ 6 files changed, 18 insertions(+) diff --git a/arch/frv/Kconfig b/arch/frv/Kconfig index eefd9a4ed156..1cce8243449e 100644 --- a/arch/frv/Kconfig +++ b/arch/frv/Kconfig @@ -17,6 +17,9 @@ config FRV select HAVE_DEBUG_STACKOVERFLOW select ARCH_NO_COHERENT_DMA_MMAP +config CPU_BIG_ENDIAN + def_bool y + config ZONE_DMA bool default y diff --git a/arch/h8300/Kconfig b/arch/h8300/Kconfig index 6e3d36f37a02..3089f7fe2abd 100644 --- a/arch/h8300/Kconfig +++ b/arch/h8300/Kconfig @@ -23,6 +23,9 @@ config H8300 select HAVE_ARCH_HASH select CPU_NO_EFFICIENT_FFS +config CPU_BIG_ENDIAN + def_bool y + config RWSEM_GENERIC_SPINLOCK def_bool y diff --git a/arch/m68k/Kconfig b/arch/m68k/Kconfig index 5abb548f0e70..353d90487c2b 100644 --- a/arch/m68k/Kconfig +++ b/arch/m68k/Kconfig @@ -24,6 +24,9 @@ config M68K select OLD_SIGSUSPEND3 select OLD_SIGACTION +config CPU_BIG_ENDIAN + def_bool y + config RWSEM_GENERIC_SPINLOCK bool default y diff --git a/arch/openrisc/Kconfig b/arch/openrisc/Kconfig index 1e95920b0737..a0f2e4a323c1 100644 --- a/arch/openrisc/Kconfig +++ b/arch/openrisc/Kconfig @@ -29,6 +29,9 @@ config OPENRISC select CPU_NO_EFFICIENT_FFS if !OPENRISC_HAVE_INST_FF1 select NO_BOOTMEM +config CPU_BIG_ENDIAN + def_bool y + config MMU def_bool y diff --git a/arch/parisc/Kconfig b/arch/parisc/Kconfig index 13648519bd41..ba7b7ddc3844 100644 --- a/arch/parisc/Kconfig +++ b/arch/parisc/Kconfig @@ -59,6 +59,9 @@ config PARISC config CPU_BIG_ENDIAN def_bool y +config CPU_BIG_ENDIAN + def_bool y + config MMU def_bool y diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig index a4a626199c47..0be3828752e5 100644 --- a/arch/sparc/Kconfig +++ b/arch/sparc/Kconfig @@ -97,6 +97,9 @@ config ARCH_PROC_KCORE_TEXT config CPU_BIG_ENDIAN def_bool y +config CPU_BIG_ENDIAN + def_bool y + config ARCH_ATU bool default y if SPARC64 -- 2.20.1