Cc: Ingo Molnar <mingo@...>, Linus Torvalds <torvalds@...>, <linux-kernel@...>, Thomas Gleixner <tglx@...>, H. Peter Anvin <hpa@...>, Yinghai Lu <yinghai.lu@...>, Yinghai Lu <yhlu.kernel@...>, <jbarnes@...>
Definitely shouldn't be assumed. At one point in the distant past I had
a ppc memcpy which would clobber a destination cacheline before reading
the source, so source and dest within a cacheline's distance would be
trouble, regardless of the direction. Arch-specific code which knows
about the arch-specific details of memcpy might be safer, I guess, but
its still fairly brittle.
J
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