[PATCH] PCI/AER: Add a null check before eeh_ops->notify_resume callback.

[Michael Ellerman]

Vaibhav Jain <vaibhav at linux.vnet.ibm.com> writes:
> This patch puts a NULL check before branching to the address pointed
> to by eeh_ops->notify_resume in eeh_report_resume(). The callback
> is used to notify the arch EEH code that a pci device is back
> online.
>
> For PPC64 presently, only an implementation for pseries platform is
> available and not for powernv. Hence without this patch EEH recovery
> on all non-virtualized hosts is causing a kernel panic when
> CONFIG_PCI_IOV is set. The panic is usually is of the form:
>
> EEH: Notify device driver to resume
> Unable to handle kernel paging request for instruction fetch
> Faulting instruction address: 0x00000000
> Oops: Kernel access of bad area, sig: 11 [#1]
> <snip>
> LR eeh_report_resume+0x218/0x220
> Call Trace:
>  eeh_report_resume+0x1f0/0x220 (unreliable)
>  eeh_pe_dev_traverse+0x98/0x170
>  eeh_handle_normal_event+0x3f4/0x650
>  eeh_handle_event+0x188/0x380
>  eeh_event_handler+0x208/0x210
>  kthread+0x168/0x1b0
>  ret_from_kernel_thread+0x5c/0xb4
>
> Cc: Bryant G. Ly <bryantly at linux.vnet.ibm.com>
> Fixes: 856e1eb9bdd4("PCI/AER: Add uevents in AER and EEH error/resume")
> Signed-off-by: Vaibhav Jain <vaibhav at linux.vnet.ibm.com>

10 out of 10 for the change log!

But yeah this is already fixed in my fixes branch, thanks anyway.

cheers