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charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspamd-Queue-Id: 09126C0014 X-Stat-Signature: po7rg3ot3117jrw6dtqyugssdjjc3iyu X-Rspam-User: X-Rspamd-Server: rspam07 X-HE-Tag: 1713543485-697587 X-HE-Meta: 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 rv1qonly yEwn953j35Yt9iAhzcDBCpRu3ExvFoTdx0+icgz2oSjaxLwTEDt2aQyum2A== 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: List-Subscribe: List-Unsubscribe: On Fri, Apr 19, 2024 at 5:11=E2=80=AFPM Michael Roth = wrote: > > On Fri, Apr 19, 2024 at 02:58:43PM +0200, David Hildenbrand wrote: > > On 18.04.24 21:41, Michael Roth wrote: > > > kvm_gmem_get_folio() may return a PTR_ERR() rather than just NULL. In > > > particular, for cases where EEXISTS is returned when FGP_CREAT_ONLY > > > flag is used. Handle this properly in __kvm_gmem_get_pfn(). > > > > > > Signed-off-by: Michael Roth > > > --- > > > virt/kvm/guest_memfd.c | 4 ++-- > > > 1 file changed, 2 insertions(+), 2 deletions(-) > > > > > > diff --git a/virt/kvm/guest_memfd.c b/virt/kvm/guest_memfd.c > > > index ccf22e44f387..9d7c6a70c547 100644 > > > --- a/virt/kvm/guest_memfd.c > > > +++ b/virt/kvm/guest_memfd.c > > > @@ -580,8 +580,8 @@ static int __kvm_gmem_get_pfn(struct file *file, = struct kvm_memory_slot *slot, > > > } > > > folio =3D kvm_gmem_get_folio(file_inode(file), index, prepare); > > > - if (!folio) > > > - return -ENOMEM; > > > + if (IS_ERR_OR_NULL(folio)) > > > + return folio ? PTR_ERR(folio) : -ENOMEM; > > > > Will it even return NULL? Staring at other filemap_grab_folio() users,= they > > all check for IS_ERR(). > > Looks like the NULL case is handled with PTR_ERR(-ENOENT), so IS_ERR() > would be sufficient. I think in the past kvm_gmem_get_folio() itself > would return NULL in some cases, but as of commit 2b01b7e994e95 that's > no longer the case. > > I'll fix this up to expect only PTR_ERR() when I re-spin v14, and also > address the other kvm_gmem_get_folio() / __filemap_get_folio() call > sites. > > > > > > if (folio_test_hwpoison(folio)) { > > > r =3D -EHWPOISON; > > > > Do we have a Fixes: tag? > > Fixes: 2b01b7e994e95 ("KVM: guest_memfd: pass error up from filemap_grab_= folio") I'll squash it so when you rebase on the new kvm-coco-queue it will go away. Thanks to both! Paolo