asm and functions with __attribute__((naked))

[dw <limegreensocks@xxxxxxxxx>]

According to the docs 
(http://gcc.gnu.org/onlinedocs/gcc/Function-Attributes.html#index-function-without-a-prologue_002fepilogue-code-2906):

"The only statements that can be safely included in naked functions are 
|asm| statements that do not have operands."

My reading of this was that "naked" didn't support "extended asm" (ie 
the one that uses colons), only basic asm (the one that can be used 
outside of functions).  However, then I saw this bit from the linux kernel:

http://lxr.free-electrons.com/source/arch/arm/kernel/kprobes.c#L377

which uses the "memory" clobber.  My next assumption was that you just 
couldn't use actual input or output params.  But then I saw this (among 
other places):

http://lxr.free-electrons.com/source/arch/arm/mm/copypage-feroceon.c#L17

which uses 3 input params.

Now I'm not sure what to think.  Is the linux kernel doing something 
unsupported/risky?  Or are the docs here just wrong?

dw