FAILED: patch "[PATCH] MIPS: cmpxchg64() and HAVE_VIRT_CPU_ACCOUNTING_GEN don't work" failed to apply to 4.4-stable tree

The patch below does not apply to the 4.4-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From: Ben Hutchings <[email protected]>
Date: Wed, 4 Oct 2017 03:46:14 +0100
Subject: [PATCH] MIPS: cmpxchg64() and HAVE_VIRT_CPU_ACCOUNTING_GEN don't work
for 32-bit SMP

__cmpxchg64_local_generic() is atomic only w.r.t tasks and interrupts on the same CPU (that's what the 'local' means). We can't use it to implement cmpxchg64() in SMP configurations.

So, for 32-bit SMP configurations:

- Don't define cmpxchg64()
- Don't enable HAVE_VIRT_CPU_ACCOUNTING_GEN, which requires it

Patchwork: https://patchwork.linux-mips.org/patch/17413/

index 43411118dd4f..b09b644cd57c 100644
@@ -64,7 +64,7 @@ config MIPS
 	select HAVE_PERF_EVENTS
 	select HAVE_REGS_AND_STACK_ACCESS_API
 	select HAVE_SYSCALL_TRACEPOINTS
-	select HAVE_VIRT_CPU_ACCOUNTING_GEN
+	select HAVE_VIRT_CPU_ACCOUNTING_GEN if 64BIT || !SMP
 	select IRQ_FORCED_THREADING
 	select MODULES_USE_ELF_RELA if MODULES && 64BIT
 	select MODULES_USE_ELF_REL if MODULES

index 903f3bf48419..ae2b4583b486 100644
@@ -202,8 +202,10 @@ static inline unsigned long __cmpxchg(volatile void *ptr, unsigned long old,
 #else
 #include <asm-generic/cmpxchg-local.h>
 #define cmpxchg64_local(ptr, o, n) __cmpxchg64_local_generic((ptr), (o), (n))
+#ifndef CONFIG_SMP
 #define cmpxchg64(ptr, o, n) cmpxchg64_local((ptr), (o), (n))
 #endif
+#endif
 
 #undef __scbeqz