| Message ID | 20231027223651.36047-2-brett.creeley@amd.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | pds/vfio: Fixes for locking bugs | expand |
> From: Brett Creeley <brett.creeley@amd.com> > Sent: Saturday, October 28, 2023 6:37 AM > > 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> is this patch still required with patch3?
On 10/30/2023 11:13 PM, Tian, Kevin wrote: > Caution: This message originated from an External Source. Use proper caution when opening attachments, clicking links, or responding. > > >> From: Brett Creeley <brett.creeley@amd.com> >> Sent: Saturday, October 28, 2023 6:37 AM >> >> 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> > > is this patch still required with patch3? Good point. It's not required anymore since there is no spinlock. Thanks, Brett
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;