On Thu, Mar 05, 2020 at 06:27:53PM -0600, Suman Anna wrote: > On 2/25/20 9:13 PM, Jason Wang wrote: > > > > On 2020/2/26 上午12:51, Suman Anna wrote: > >> Hi Jason, > >> > >> On 2/24/20 11:39 PM, Jason Wang wrote: > >>> On 2020/2/25 上午5:26, Suman Anna wrote: > >>>> The functions vring_new_virtqueue() and __vring_new_virtqueue() are > >>>> used > >>>> with split rings, and any allocations within these functions are > >>>> managed > >>>> outside of the .we_own_ring flag. The commit cbeedb72b97a > >>>> ("virtio_ring: > >>>> allocate desc state for split ring separately") allocates the desc > >>>> state > >>>> within the __vring_new_virtqueue() but frees it only when the > >>>> .we_own_ring > >>>> flag is set. This leads to a memory leak when freeing such allocated > >>>> virtqueues with the vring_del_virtqueue() function. > >>>> > >>>> Fix this by moving the desc_state free code outside the flag and only > >>>> for split rings. Issue was discovered during testing with remoteproc > >>>> and virtio_rpmsg. > >>>> > >>>> Fixes: cbeedb72b97a ("virtio_ring: allocate desc state for split ring > >>>> separately") > >>>> Signed-off-by: Suman Anna<s-a...@ti.com> > >>>> --- > >>>> drivers/virtio/virtio_ring.c | 4 ++-- > >>>> 1 file changed, 2 insertions(+), 2 deletions(-) > >>>> > >>>> diff --git a/drivers/virtio/virtio_ring.c > >>>> b/drivers/virtio/virtio_ring.c > >>>> index 867c7ebd3f10..58b96baa8d48 100644 > >>>> --- a/drivers/virtio/virtio_ring.c > >>>> +++ b/drivers/virtio/virtio_ring.c > >>>> @@ -2203,10 +2203,10 @@ void vring_del_virtqueue(struct virtqueue *_vq) > >>>> vq->split.queue_size_in_bytes, > >>>> vq->split.vring.desc, > >>>> vq->split.queue_dma_addr); > >>>> - > >>>> - kfree(vq->split.desc_state); > >>>> } > >>>> } > >>>> + if (!vq->packed_ring) > >>>> + kfree(vq->split.desc_state); > >>> Nitpick, it looks to me it would be more clear if we just free > >>> desc_state unconditionally here (and remove the kfree for packed above). > >> OK, are you sure you want that to be folded into this patch? It looks to > >> me a separate cleanup/consolidation patch, and packed desc_state does > >> not suffer this memleak, and need not be backported into stable kernels. > >> > >> regards > >> Suman > > > > > > Though it's just a small tweak, I'm fine for leaving it for future. > > > > So > > > > Acked-by: Jason Wang <jasow...@redhat.com> > > > > Mike, > Ping on this. I don't see the patch in -next yet. Can we get this into > the current -rc please? > > regards > Suman
Yes will queue it shortly, thanks! _______________________________________________ Virtualization mailing list Virtualization@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/virtualization