On 12/20/2015 05:47 PM, Eric W. Biederman wrote:
Dongsheng Yang <yangds.f...@cn.fujitsu.com> writes:
On 12/20/2015 10:37 AM, Al Viro wrote:
On Sun, Dec 20, 2015 at 10:14:29AM +0800, Dongsheng Yang wrote:
On 12/17/2015 07:23 PM, Dongsheng Yang wrote:
Hi guys,
We are working on making core dump behaviour isolated in
container. But the problem is, the /proc/sys/kernel/core_pattern
is a kernel wide setting, not belongs to a container.
So we want to add core_pattern into mnt namespace. What
do you think about it?
Hi Eric,
I found your patch about "net: Implement the per network namespace
sysctl infrastructure", I want to do the similar thing
in mnt namespace. Is that suggested way?
Why mnt namespace and not something else?
Hi Al,
Well, because core_pattern indicates the path to store core file.
In different mnt namespace, we would like to change the path with
different value.
In addition, Let's considering other namespaces:
UTS ns: contains informations of kernel and arch, not proper for core_pattern.
IPC ns: communication informations, not proper for core_pattern
PID ns: core_pattern is not related with pid
net ns: obviousely no.
user ns: not proper too.
Then I believe it's better to do this in mnt namespace. of course,
core_pattern is just one example. After this infrastructure finished,
we can implement more sysctls as per-mnt if necessary, I think.
Al, what do you think about this idea?
The hard part is not the sysctl. The hard part is starting the usermode
helper, in an environment that it can deal with. The mount namespace
really provides you with no help there.
Do you mean the core dump helper? But I think I don't want to touch it
in my development. I think I can use non-pipe way to get what I want,
Let me try to explain what I want here.
(1). introduce a --core-path option in docker run command to specify the
path in host to store core file in one container.
E.g: docker run --core-path=/core/test --name=test IMAGE
(2). When the container starting, docker attach a volume to it, similar
with "-v /core/test:/var/lib/docker/coredump". That means, the path of
/var/lib/docker/coredump in container is a link to /core/test in host.
(3). Set the /proc/sys/kernel/core_pattern in container as
"/var/lib/docker/coredump". But that should not affect the core_pattern
in host or other containers.
Then I think I can collect the core files from each container and save
them in the paths where I want.
Thanx
Yang
Eric
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
