On Fri, Dec 07, 2018 at 10:52:49AM -0800, Linus Torvalds wrote: > On Fri, Dec 7, 2018 at 10:44 AM Sean Christopherson > <sean.j.christopher...@intel.com> wrote: > > > > Remove the per-bit decoding of the error code and instead print the raw > > error code followed by a brief description of what caused the fault, the > > effective privilege level of the faulting access, and whether the fault > > originated in user code or kernel code. > > This doesn't quite work as-is, though. > > For example, at least the PK bit is independent of the other bits and > would be interesting in the human-legible version, but doesn't show up > there at all.
Heh, I actually intentionally omitted protection keys thinking it'd be superfluous, i.e. "go look at the error code bits if you care that much". > That said, I think the end result might be more legible than the > previous version, so this approach may well be good, it just needs at > least that "permissions violation" part to be extended with whether > it was PK or not. > > Also, shouldn't we show the SGX bit too as some kind of "during SGX" > extension on the "in user/kernel space" part? The SGX bit isn't defined in mainline yet. But yeah, I can see how printing e.g. "SGX EPCM violation" would be a lot more helpful than a vanilla "permissions violation". I'll send a v2 with the PK bit added and a slightly reworded changelog.
