| Message ID | 20231011230115.35719-2-brett.creeley@amd.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | pds/vfio: Fixes for locking bugs | expand |
> -----Original Message----- > From: Brett Creeley [mailto:brett.creeley@amd.com] > Sent: 12 October 2023 00:01 > To: jgg@ziepe.ca; yishaih@nvidia.com; Shameerali Kolothum Thodi > <shameerali.kolothum.thodi@huawei.com>; kevin.tian@intel.com; > alex.williamson@redhat.com; dan.carpenter@linaro.org > Cc: kvm@vger.kernel.org; linux-kernel@vger.kernel.org; > brett.creeley@amd.com; shannon.nelson@amd.com > Subject: [PATCH v2 vfio 1/3] pds/vfio: Fix spinlock bad magic BUG > > The following BUG was found when running on a kernel with > CONFIG_DEBUG_SPINLOCK=y set: > > BUG: spinlock bad magic on CPU#2, bash/2481 > lock: 0xffff8d6052a88f50, .magic: 00000000, .owner: > <none>/-1, .owner_cpu: 0 > Call Trace: > <TASK> > dump_stack_lvl+0x36/0x50 > do_raw_spin_lock+0x79/0xc0 > pds_vfio_reset+0x1d/0x60 [pds_vfio_pci] > pci_reset_function+0x4b/0x70 > reset_store+0x5b/0xa0 > kernfs_fop_write_iter+0x137/0x1d0 > vfs_write+0x2de/0x410 > ksys_write+0x5d/0xd0 > do_syscall_64+0x3b/0x90 > entry_SYSCALL_64_after_hwframe+0x6e/0xd8 > > As shown, the .magic: 00000000, does not match the expected value. This > is because spin_lock_init() is never called for the reset_lock. Fix > this by calling spin_lock_init(&pds_vfio->reset_lock) when initializing > the device. > > Signed-off-by: Brett Creeley <brett.creeley@amd.com> > Reviewed-by: Shannon Nelson <shannon.nelson@amd.com> Reviewed-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com> I think this needs to be fixed in HiSilicon driver as well. I will send out a patch. Thanks, Shameer > --- > drivers/vfio/pci/pds/vfio_dev.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/drivers/vfio/pci/pds/vfio_dev.c b/drivers/vfio/pci/pds/vfio_dev.c > index 649b18ee394b..c351f588fa13 100644 > --- a/drivers/vfio/pci/pds/vfio_dev.c > +++ b/drivers/vfio/pci/pds/vfio_dev.c > @@ -155,6 +155,8 @@ static int pds_vfio_init_device(struct vfio_device > *vdev) > > pds_vfio->vf_id = vf_id; > > + spin_lock_init(&pds_vfio->reset_lock); > + > vdev->migration_flags = VFIO_MIGRATION_STOP_COPY | > VFIO_MIGRATION_P2P; > vdev->mig_ops = &pds_vfio_lm_ops; > vdev->log_ops = &pds_vfio_log_ops; > -- > 2.17.1
diff --git a/drivers/vfio/pci/pds/vfio_dev.c b/drivers/vfio/pci/pds/vfio_dev.c index 649b18ee394b..c351f588fa13 100644 --- a/drivers/vfio/pci/pds/vfio_dev.c +++ b/drivers/vfio/pci/pds/vfio_dev.c @@ -155,6 +155,8 @@ static int pds_vfio_init_device(struct vfio_device *vdev) pds_vfio->vf_id = vf_id; + spin_lock_init(&pds_vfio->reset_lock); + vdev->migration_flags = VFIO_MIGRATION_STOP_COPY | VFIO_MIGRATION_P2P; vdev->mig_ops = &pds_vfio_lm_ops; vdev->log_ops = &pds_vfio_log_ops;