Messages in this thread | | | Date | Fri, 7 Apr 2017 16:45:26 +0200 | From | Peter Zijlstra <> | Subject | Re: [kernel-hardening] Re: [RFC v2][PATCH 04/11] x86: Implement __arch_rare_write_begin/unmap() |
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On Fri, Apr 07, 2017 at 12:51:15PM +0200, Mathias Krause wrote: > Why that? It allows fast and CPU local modifications of r/o memory. > OTOH, an approach that needs to fiddle with page table entries > requires global synchronization to keep the individual TLB states in > sync. Hmm.. Not that fast, I'd say.
The fixmaps used for kmap_atomic are per-cpu, no global sync required.
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