[Skiboot] [PATCH] phb4: Reassign link_retries counter in IODA purge

Stewart Smith stewart at linux.vnet.ibm.com
Thu Oct 5 18:10:26 AEDT 2017

"Guilherme G. Piccoli" <gpiccoli at linux.vnet.ibm.com> writes:
> Recently, a link_retries counter was added in pci/phb4 in order
> Skiboot can retry to train a link some times - default number of
> attempts to retrain a link is 3.
> Happens that, if during a regular boot process we exhaust the
> link retries and fail to train a PHB, the variable link_retries
> is stuck in 0. If a kdump happens later, a PHB reset procedure is
> triggered by Linux and, since we have a decrement-and-test in this
> variable, we end up setting it to -1; it's unsigned, hence we get
> an overflow.
> This patch fixes the issue by reassigning the default value to
> link_retries in every IODA purge.
> Signed-off-by: Guilherme G. Piccoli <gpiccoli at linux.vnet.ibm.com>
> ---
>  hw/phb4.c | 2 ++
>  1 file changed, 2 insertions(+)

Merged as of 784da79b85537ded99e8d1890b46e3a804d93295

Stewart Smith
OPAL Architect, IBM.

More information about the Skiboot mailing list