Le 09/03/2017 à 05:37, Bharata B Rao a écrit :
The following warning is seen when a CPU is hot unplugged on a PowerKVM
guest:
refcount_t: underflow; use-after-free.
[ cut here ]
WARNING: CPU: 0 PID: 53 at lib/refcount.c:128 refcount_sub_and_test+0xd8/0xf0
Modules linke
I get the error when removing a CPU that has been hotplugged after boot.
On 03/14/2017 03:42 PM, Tyrel Datwyler wrote:
> On 03/13/2017 03:29 AM, Bharata B Rao wrote:
>> On Thu, Mar 09, 2017 at 01:34:00PM -0800, Tyrel Datwyler wrote:
>>> On 03/08/2017 08:37 PM, Bharata B Rao wrote:
The followi
>> So you suggest that adding of_node_get() to __of_attach_node_sysfs()
>> is the right fix ?
>
> If I understand that this only creates for hot-added cpus then no. Also
> for this to be the correct fix I would expect to see this recreate for
> all hot-remove operations such as memory and pci dev
On 03/13/2017 03:29 AM, Bharata B Rao wrote:
> On Thu, Mar 09, 2017 at 01:34:00PM -0800, Tyrel Datwyler wrote:
>> On 03/08/2017 08:37 PM, Bharata B Rao wrote:
>>> The following warning is seen when a CPU is hot unplugged on a PowerKVM
>>> guest:
>>
>> Is this the case with cpus present at boot? Wha
On Thu, Mar 09, 2017 at 01:34:00PM -0800, Tyrel Datwyler wrote:
> On 03/08/2017 08:37 PM, Bharata B Rao wrote:
> > The following warning is seen when a CPU is hot unplugged on a PowerKVM
> > guest:
>
> Is this the case with cpus present at boot? What about cpus hotplugged
> after boot?
I have obs
On 03/08/2017 08:37 PM, Bharata B Rao wrote:
> The following warning is seen when a CPU is hot unplugged on a PowerKVM
> guest:
Is this the case with cpus present at boot? What about cpus hotplugged
after boot?
My suspicion is that the refcount was wrong to begin with. See my
comments below. The
Bharata B Rao writes:
> The following warning is seen when a CPU is hot unplugged on a PowerKVM
> guest:
>
> refcount_t: underflow; use-after-free.
...
>
> Fix this by ensuring that of_node_put() is called only from the
> error path in dlpar_cpu_remove_by_index(). In the normal path,
> of_node_pu
> Fix this by ensuring that of_node_put() is called only from the
> error path in dlpar_cpu_remove_by_index(). In the normal path,
> of_node_put() happens as part of dlpar_detach_node().
>
> Signed-off-by: Bharata B Rao
> Cc: Nathan Fontenot
> ---
> Changes in v1:
> - Fixed the refcount problem
The following warning is seen when a CPU is hot unplugged on a PowerKVM
guest:
refcount_t: underflow; use-after-free.
[ cut here ]
WARNING: CPU: 0 PID: 53 at lib/refcount.c:128 refcount_sub_and_test+0xd8/0xf0
Modules linked in:
CPU: 0 PID: 53 Comm: kworker/u510:1 Not tainte
