Parav Pandit
2021-Nov-23 03:12 UTC
[PATCH] vdpa_sim: avoid putting an uninitialized iova_domain
> From: Longpeng(Mike) <longpeng2 at huawei.com> > Sent: Monday, November 22, 2021 5:52 PM > > From: Longpeng <longpeng2 at huawei.com> > > The system will crash if we put an uninitialized iova_domain, this could > happen when an error occurs before initializing the iova_domain in > vdpasim_create(). > > BUG: kernel NULL pointer dereference, address: 0000000000000000 ... > RIP: 0010:__cpuhp_state_remove_instance+0x96/0x1c0 > ... > Call Trace: > <TASK> > put_iova_domain+0x29/0x220 > vdpasim_free+0xd1/0x120 [vdpa_sim] > vdpa_release_dev+0x21/0x40 [vdpa] > device_release+0x33/0x90 > kobject_release+0x63/0x160 > vdpasim_create+0x127/0x2a0 [vdpa_sim] > vdpasim_net_dev_add+0x7d/0xfe [vdpa_sim_net] > vdpa_nl_cmd_dev_add_set_doit+0xe1/0x1a0 [vdpa] > genl_family_rcv_msg_doit+0x112/0x140 > genl_rcv_msg+0xdf/0x1d0 > ... > > So we must make sure the iova_domain is already initialized before put it. > > In addition, we may get the following warning in this case: > WARNING: ... drivers/iommu/iova.c:344 iova_cache_put+0x58/0x70 > > So we must make sure the iova_cache_put() is invoked only if the > iova_cache_get() is already invoked. Let's fix it together. > > Signed-off-by: Longpeng <longpeng2 at huawei.com>Can you please add the fixes tag here so that older kernels can take this fix?
Jason Wang
2021-Nov-23 04:12 UTC
[PATCH] vdpa_sim: avoid putting an uninitialized iova_domain
On Tue, Nov 23, 2021 at 11:12 AM Parav Pandit <parav at nvidia.com> wrote:> > > > > From: Longpeng(Mike) <longpeng2 at huawei.com> > > Sent: Monday, November 22, 2021 5:52 PM > > > > From: Longpeng <longpeng2 at huawei.com> > > > > The system will crash if we put an uninitialized iova_domain, this could > > happen when an error occurs before initializing the iova_domain in > > vdpasim_create(). > > > > BUG: kernel NULL pointer dereference, address: 0000000000000000 ... > > RIP: 0010:__cpuhp_state_remove_instance+0x96/0x1c0 > > ... > > Call Trace: > > <TASK> > > put_iova_domain+0x29/0x220 > > vdpasim_free+0xd1/0x120 [vdpa_sim] > > vdpa_release_dev+0x21/0x40 [vdpa] > > device_release+0x33/0x90 > > kobject_release+0x63/0x160 > > vdpasim_create+0x127/0x2a0 [vdpa_sim] > > vdpasim_net_dev_add+0x7d/0xfe [vdpa_sim_net] > > vdpa_nl_cmd_dev_add_set_doit+0xe1/0x1a0 [vdpa] > > genl_family_rcv_msg_doit+0x112/0x140 > > genl_rcv_msg+0xdf/0x1d0 > > ... > > > > So we must make sure the iova_domain is already initialized before put it. > > > > In addition, we may get the following warning in this case: > > WARNING: ... drivers/iommu/iova.c:344 iova_cache_put+0x58/0x70 > > > > So we must make sure the iova_cache_put() is invoked only if the > > iova_cache_get() is already invoked. Let's fix it together. > > > > Signed-off-by: Longpeng <longpeng2 at huawei.com> > > Can you please add the fixes tag here so that older kernels can take this fix? >I guess it's 4080fc106750 ("vdpa_sim: use iova module to allocate IOVA addresses") Thanks