On Sat, 2015-02-28 at 13:49 -0800, Linus Torvalds wrote: .../... > - we handle write faults separately (see the first part of access_error() > > - so now we know it was a read or an instruction fetch > > - if PF_PROT is set, that means that the present bit was set in the > page tables, so it must have been an exec access to a NX page > > - otherwise, we just say "PROTNONE means no access, otherwise > populate the page tables" > > .. and if it turns out that it was a PF_INSTR to a NX page, we'll end > up taking the page fault *again* after it's been populated, and now > since the page table was populated, the access_error() will catch it > with the PF_PROT case. > > Or something like that. I might have screwed up some detail, but it > should all work. I see, it should work yes, I'll still add that FAULT_FLAG_EXEC for those who can tell reliably but it shouldn't hurt for x86 to not set it. Cheers, Ben. > Linus > -- > To unsubscribe from this list: send the line "unsubscribe linux-arch" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
