On Wed, 17 Jun 2020 21:06:17 -0400 Sasha Levin <sashal@xxxxxxxxxx> wrote: > From: Qian Cai <cai@xxxxxx> > > [ Upstream commit 1518ac272e789cae8c555d69951b032a275b7602 ] > > Finished a qemu-kvm (-device vfio-pci,host=0001:01:00.0) triggers a few > memory leaks after a while because vfio_pci_set_ctx_trigger_single() > calls eventfd_ctx_fdget() without the matching eventfd_ctx_put() later. > Fix it by calling eventfd_ctx_put() for those memory in > vfio_pci_release() before vfio_device_release(). > > unreferenced object 0xebff008981cc2b00 (size 128): > comm "qemu-kvm", pid 4043, jiffies 4294994816 (age 9796.310s) > hex dump (first 32 bytes): > 01 00 00 00 6b 6b 6b 6b 00 00 00 00 ad 4e ad de ....kkkk.....N.. > ff ff ff ff 6b 6b 6b 6b ff ff ff ff ff ff ff ff ....kkkk........ > backtrace: > [<00000000917e8f8d>] slab_post_alloc_hook+0x74/0x9c > [<00000000df0f2aa2>] kmem_cache_alloc_trace+0x2b4/0x3d4 > [<000000005fcec025>] do_eventfd+0x54/0x1ac > [<0000000082791a69>] __arm64_sys_eventfd2+0x34/0x44 > [<00000000b819758c>] do_el0_svc+0x128/0x1dc > [<00000000b244e810>] el0_sync_handler+0xd0/0x268 > [<00000000d495ef94>] el0_sync+0x164/0x180 > unreferenced object 0x29ff008981cc4180 (size 128): > comm "qemu-kvm", pid 4043, jiffies 4294994818 (age 9796.290s) > hex dump (first 32 bytes): > 01 00 00 00 6b 6b 6b 6b 00 00 00 00 ad 4e ad de ....kkkk.....N.. > ff ff ff ff 6b 6b 6b 6b ff ff ff ff ff ff ff ff ....kkkk........ > backtrace: > [<00000000917e8f8d>] slab_post_alloc_hook+0x74/0x9c > [<00000000df0f2aa2>] kmem_cache_alloc_trace+0x2b4/0x3d4 > [<000000005fcec025>] do_eventfd+0x54/0x1ac > [<0000000082791a69>] __arm64_sys_eventfd2+0x34/0x44 > [<00000000b819758c>] do_el0_svc+0x128/0x1dc > [<00000000b244e810>] el0_sync_handler+0xd0/0x268 > [<00000000d495ef94>] el0_sync+0x164/0x180 > > Signed-off-by: Qian Cai <cai@xxxxxx> > Signed-off-by: Alex Williamson <alex.williamson@xxxxxxxxxx> > Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> > --- > drivers/vfio/pci/vfio_pci.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c > index 6c6b37b5c04e..080e6608f297 100644 > --- a/drivers/vfio/pci/vfio_pci.c > +++ b/drivers/vfio/pci/vfio_pci.c > @@ -519,6 +519,10 @@ static void vfio_pci_release(void *device_data) > vfio_pci_vf_token_user_add(vdev, -1); > vfio_spapr_pci_eeh_release(vdev->pdev); > vfio_pci_disable(vdev); > + if (vdev->err_trigger) > + eventfd_ctx_put(vdev->err_trigger); > + if (vdev->req_trigger) > + eventfd_ctx_put(vdev->req_trigger); > } > > mutex_unlock(&vdev->reflck->lock); This has a fix pending, I'd suggest not picking it on its own: https://lore.kernel.org/kvm/20200616085052.sahrunsesjyjeyf2@xxxxxxxxxxxxx/ https://lore.kernel.org/kvm/159234276956.31057.6902954364435481688.stgit@xxxxxxxxxx/ Thanks, Alex