Il 08/09/2013 11:04, Gleb Natapov ha scritto: > On Thu, Sep 05, 2013 at 02:21:53PM +0200, Paolo Bonzini wrote: >> Page tables in a read-only memory slot will currently cause a triple >> fault when running with shadow paging, because the page walker uses >> gfn_to_hva and it fails on such a slot. >> >> TianoCore uses such a page table. The idea is that, on real hardware, >> the firmware can already run in 64-bit flat mode when setting up the >> memory controller. Real hardware seems to be fine with that as long as >> the accessed/dirty bits are set. Thus, this patch saves whether the >> slot is readonly, and later checks it when updating the accessed and >> dirty bits. >> >> Note that this scenario is not supported by NPT at all, as explained by >> comments in the code. >> >> Cc: stable@xxxxxxxxxxxxxxx >> Cc: kvm@xxxxxxxxxxxxxxx >> Cc: Xiao Guangrong <xiaoguangrong@xxxxxxxxxxxxxxxxxx> >> Cc: Gleb Natapov <gleb@xxxxxxxxxx> >> Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx> > I would prefer to change gfn_to_hva_read() to gfn_to_hva_prot() in this > patch already, it will not make it any bigger Sure. Paolo -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
