On Fri, 30 Sep 2022 16:19:28 +0200 David Hildenbrand <david@xxxxxxxxxx> wrote: > Let's stop breaking COW via a fake write fault and let's use > FAULT_FLAG_UNSHARE instead. This avoids any wrong side effects of the fake > write fault, such as mapping the PTE writable and marking the pte > dirty/softdirty. > > Also, this fixes KSM interaction with userfaultfd-wp: when we have a KSM > page that's write-protected by userfaultfd, break_ksm()->handle_mm_fault() > will fail with VM_FAULT_SIGBUS and will simpy return in break_ksm() with 0. > The warning in dmesg indicates this wrong handling: We're at -rc7. I'd prefer to avoid merging larger patchsets at this time. Is there some minimal fix for 6.0 and -stable? Or is the problem non-serious enough to only fix it in 6.1 and later?
