Re: [PATCH v3 vfio 1/3] pds/vfio: Fix spinlock bad magic BUG

[Brett Creeley]

On 10/30/2023 11:13 PM, Tian, Kevin wrote:
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>
> > From: Brett Creeley <brett.creeley@xxxxxxx>
> > 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@xxxxxxx>
> > Reviewed-by: Shannon Nelson <shannon.nelson@xxxxxxx>
>
> is this patch still required with patch3?

Good point. It's not required anymore since there is no spinlock.

Thanks,

Brett