James Bottomley b7d4581844 [PARISC] prevent speculative re-read on cache flush ... According to Appendix F, the TLB is the primary arbiter of speculation. Thus, if a page has a TLB entry, it may be speculatively read into the cache. On linux, this can cause us incoherencies because if we're about to do a disk read, we call get_user_pages() to do the flush/invalidate in user space, but we still potentially have the user TLB entries, and the cache could speculate the lines back into userspace (thus causing stale data to be used). This is fixed by purging the TLB entries before we flush through the tmpalias space. Now, the only way the line could be re-speculated is if the user actually tries to touch it (which is not allowed). Signed-off-by: James Bottomley <James.Bottomley@suse.de>		2011-04-15 12:55:56 -05:00
..
asm	[PARISC] prevent speculative re-read on cache flush	2011-04-15 12:55:56 -05:00