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
> From: Brett Creeley <[email protected]>
> 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 <[email protected]>
> Reviewed-by: Shannon Nelson <[email protected]>
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 <[email protected]>
>> 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 <[email protected]>
>> Reviewed-by: Shannon Nelson <[email protected]>
>
> is this patch still required with patch3?
Good point. It's not required anymore since there is no spinlock.
Thanks,
Brett