r...@linux.ibm.com>, linux-par...@vger.kernel.org, Max Filippov <jcmvb...@gmail.com>, linux-ker...@vger.kernel.org, Johannes Berg <johan...@sipsolutions.net>, Dinh Nguyen <dingu...@kernel.org>, linux-ri...@lists.infradead.org, Palmer Dabbelt <pal...@dabbelt.com>, Sven Schnelle <sv...@linux.ibm.com>, linux-al...@vger.kernel.org, Ivan Kokshaysky <i...@jurassic.park.msu.ru>, Andrew Morton <a...@linux-foundation.org>, Thomas Bogendoerfer <tsbog...@alpha.franken.de>, linuxppc-dev@lists.ozlabs.org, "David S . Miller" <da...@davemloft.net> Errors-To: linuxppc-dev-bounces+archive=mail-archive....@lists.ozlabs.org Sender: "Linuxppc-dev" <linuxppc-dev-bounces+archive=mail-archive....@lists.ozlabs.org>
On Mon, May 30, 2022 at 12:00:52PM -0400, Peter Xu wrote: > On Mon, May 30, 2022 at 11:52:54AM -0400, Peter Xu wrote: > > On Mon, May 30, 2022 at 11:35:10AM +0200, Christian Borntraeger wrote: > > > > diff --git a/arch/s390/mm/fault.c b/arch/s390/mm/fault.c > > > > index 4608cc962ecf..e1d40ca341b7 100644 > > > > --- a/arch/s390/mm/fault.c > > > > +++ b/arch/s390/mm/fault.c > > > > @@ -436,12 +436,11 @@ static inline vm_fault_t do_exception(struct > > > > pt_regs *regs, int access) > > > > /* The fault is fully completed (including releasing mmap lock) > > > > */ > > > > if (fault & VM_FAULT_COMPLETED) { > > > > - /* > > > > - * Gmap will need the mmap lock again, so retake it. > > > > TODO: > > > > - * only conditionally take the lock when CONFIG_PGSTE > > > > set. > > > > - */ > > > > - mmap_read_lock(mm); > > > > - goto out_gmap; > > > > + if (gmap) { > > > > + mmap_read_lock(mm); > > > > + goto out_gmap; > > > > + } fault = 0; <---- > > > > + goto out; > > Hmm, right after I replied I found "goto out" could be problematic, since > all s390 callers of do_exception() will assume it an error condition (side > note: "goto out_gmap" contains one step to clear "fault" to 0). I'll > replace this with "return 0" instead if it looks good to both of you. > > I'll wait for a confirmation before reposting. Thanks, Right, that was stupid. Thanks for double checking! However could you please add "fault = 0" just in front of the goto out like above? I'd like to avoid having returns and gotos mixed.