On Thu, Aug 29, 2024 at 09:04:37AM +0200, Jan Beulich wrote: > On 29.08.2024 02:35, Stefano Stabellini wrote: > > On Mon, 29 Jul 2024, Stefano Stabellini wrote: > >> On Mon, 29 Jul 2024, Federico Serafini wrote: > >>> Add defensive return statement at the end of an unreachable > >>> default case. Other than improve safety, this meets the requirements > >>> to deviate a violation of MISRA C Rule 16.3: "An unconditional `break' > >>> statement shall terminate every switch-clause". > >>> > >>> Signed-off-by: Federico Serafini <federico.seraf...@bugseng.com> > >> > >> Reviewed-by: Stefano Stabellini <sstabell...@kernel.org> > >> > >>> --- > >>> No changes from v3 and v4, further feedback on this thread would be > >>> appreciated: > >>> https://lists.xenproject.org/archives/html/xen-devel/2024-07/msg00474.html > > > > Looking at the older threads, I looks like Jan suggested EACCES, I also > > think it is marginally better. My R-b stands also for EACCES. Jan, I > > think you should go ahead and fix on commit > > No, I very definitely want a 2nd x86 maintainer opinion here. Or a better > suggestion for the error code to use by anyone. After all, as you confirm, > EACCES is only marginally better.
Hm, the only alternative I could suggest is using ERANGE, to signal the value of opt_mmio_relax is out of the expected range, however that could be confusing for the callers? One benefit of using ERANGE is that there's currently no return path in get_page_from_l1e() with that error code, so it would be very easy to spot when an unexpected value of opt_mmio_relax is found. However there are no guarantees that further error paths might use that error code. Thanks, Roger.
