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d7dd2ff11b
Currently parisc has the whole kernel marked as RWX, meaning any kernel page at all is eligible to be executed. This can cause a theoretical problem on systems with combined I/D TLB because the act of referencing a page causes a TLB insertion with an executable bit. This TLB entry may be used by the CPU as the basis for speculating the page into the I-Cache. If this speculated page is subsequently used for a user process, there is the possibility we will get a stale I-cache line picked up as the binary executes. As a point of good practise, only mark actual kernel text pages as executable. The same has to be done for init_text pages, but they're converted to data pages (and the I-Cache flushed) when the init memory is released. Signed-off-by: James Bottomley <James.Bottomley@suse.de>