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charset=iso-8859-15 Content-Disposition: inline In-Reply-To: <20230125233554.153109-6-surenb@google.com> X-Rspamd-Queue-Id: 30E1618000C X-Stat-Signature: jy4a4gqg5qqzejfy6aaubecpaznkxtz7 X-Rspam-User: X-Rspamd-Server: rspam08 X-HE-Tag: 1674746368-287870 X-HE-Meta: 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 63mTt1Sj 9M9RhwpMzPX3Orwxl/H5sliIBu9O1sufqEtKi6DaBvraU8nSlBChqj6zon/6n2c0/FXkybXzPtCbNLK6mwrn7+XTngkzEsQ7y5zzg67eKmJRJlMjvEaWfSO++u4R3QBpOWXu4B19xTVDRxo82YjdbA3DHUnqqJgrBFX9JxHbc4nssogtFyZk+5TBhcnKojC9+eLBA0+hiKguYvPeekLd/rvfaSMlls3m+C9v6JeuJaRMcsWxlfwiw1i5vDB5YnuQyZ9WKu6GeBfIeo08eXc5MN/fQJq6g3bzuli9G7piXgvXoMU4SJ7kwH5JHF49M/b3wEFtuWBDM3kBbBbCLfAKOYE94pIpzBADYSd7c7XKngdQlXspISIPjKbgChv9GXT+We7U6 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Wed, Jan 25, 2023 at 03:35:52PM -0800, Suren Baghdasaryan wrote: > Replace indirect modifications to vma->vm_flags with calls to modifier > functions to be able to track flag changes and to keep vma locking > correctness. > > Signed-off-by: Suren Baghdasaryan > Acked-by: Michal Hocko > --- > arch/powerpc/kvm/book3s_hv_uvmem.c | 5 ++++- > arch/s390/mm/gmap.c | 5 ++++- > 2 files changed, 8 insertions(+), 2 deletions(-) > > diff --git a/arch/powerpc/kvm/book3s_hv_uvmem.c b/arch/powerpc/kvm/book3s_hv_uvmem.c > index 1d67baa5557a..325a7a47d348 100644 > --- a/arch/powerpc/kvm/book3s_hv_uvmem.c > +++ b/arch/powerpc/kvm/book3s_hv_uvmem.c > @@ -393,6 +393,7 @@ static int kvmppc_memslot_page_merge(struct kvm *kvm, > { > unsigned long gfn = memslot->base_gfn; > unsigned long end, start = gfn_to_hva(kvm, gfn); > + unsigned long vm_flags; > int ret = 0; > struct vm_area_struct *vma; > int merge_flag = (merge) ? MADV_MERGEABLE : MADV_UNMERGEABLE; > @@ -409,12 +410,14 @@ static int kvmppc_memslot_page_merge(struct kvm *kvm, > ret = H_STATE; > break; > } > + vm_flags = vma->vm_flags; > ret = ksm_madvise(vma, vma->vm_start, vma->vm_end, > - merge_flag, &vma->vm_flags); > + merge_flag, &vm_flags); > if (ret) { > ret = H_STATE; > break; > } > + reset_vm_flags(vma, vm_flags); > start = vma->vm_end; > } while (end > vma->vm_end); Add a comment on why the vm_flags are copied in case someone "optimises" this in the future? Something like /* Copy vm_flags to avoid any partial modifications in ksm_madvise. */ > > diff --git a/arch/s390/mm/gmap.c b/arch/s390/mm/gmap.c > index 3a695b8a1e3c..d5eb47dcdacb 100644 > --- a/arch/s390/mm/gmap.c > +++ b/arch/s390/mm/gmap.c > @@ -2587,14 +2587,17 @@ int gmap_mark_unmergeable(void) > { > struct mm_struct *mm = current->mm; > struct vm_area_struct *vma; > + unsigned long vm_flags; > int ret; > VMA_ITERATOR(vmi, mm, 0); > > for_each_vma(vmi, vma) { > + vm_flags = vma->vm_flags; > ret = ksm_madvise(vma, vma->vm_start, vma->vm_end, > - MADV_UNMERGEABLE, &vma->vm_flags); > + MADV_UNMERGEABLE, &vm_flags); > if (ret) > return ret; > + reset_vm_flags(vma, vm_flags); Same. Not necessary as such as there are few users of ksm_madvise and I doubt it'll introduce new surprises. With or without the comment; Acked-by: Mel Gorman -- Mel Gorman SUSE Labs