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 <[email protected]>
Reviewed-by: Shannon Nelson <[email protected]>
---
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
> -----Original Message-----
> From: Brett Creeley [mailto:[email protected]]
> Sent: 12 October 2023 00:01
> To: [email protected]; [email protected]; Shameerali Kolothum Thodi
> <[email protected]>; [email protected];
> [email protected]; [email protected]
> Cc: [email protected]; [email protected];
> [email protected]; [email protected]
> 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 <[email protected]>
> Reviewed-by: Shannon Nelson <[email protected]>
Reviewed-by: Shameer Kolothum <[email protected]>
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