On 1/14/2019 5:06 AM, Jiri Kosina wrote:
On Mon, 14 Jan 2019, Pavel Machek wrote:
Frankly I'd not call it Meltdown, as it works only on data in the cache,
so the defense is completely different. Seems more like a l1tf
:-).
Meltdown on x86 also seems to work only for data in L1D, but the pipeline
could be constructed in a way that data are actually fetched into L1D
before speculation gives up, which is not the case on ppc (speculation
aborts on L2->L1 propagation IIRC). That's why flushing L1D on ppc is
sufficient, but on x86 it's not.
assuming L1D is not shared between SMT threads obviously :)
