Hi Leon,
Reply to you interleaved.
For your first worry about madness looping to query device, what's
about changing pr_err to pr_debug with using dynamic debug feature?
Thanks
Changcheng
On 18:51 Fri 12 Apr, Leon Romanovsky wrote:
> On Fri, Apr 12, 2019 at 10:41:54PM +0800, Liu, Changcheng wrote:
> > Hi Jason,
>
> Please don't do top-posting.
>
> > 1. When userspace get "-EACCES" value, it shouldn't continue query
> > within limited times. There's not much log.
>
> What will prevent from me to call such bad application in the loop?
No good method. Currently, ceph will abort application in this case.
>
> >
> > 2. It's helpful to know the permission problem through kernel logs.
>
> It is not kernel problem, but application. Kernel logs is not right
> place for it.
rdma_cm libary only report "query device failed and returned status
code: 13". dmesg doesn't show why it's permissioned denied after long
time.
>
> >
> > 3. I hit one userspace app crash and checked several aspects without
> > any finding until dynamic trace the kernel to know that why
> > "permission" is denied in ib_uverbs_write function.
>
> It is not different from many other errors returned from the kernel.
When hitting the "permission" problem, I swith to use root user to run
the app. But still hit the problem without any info.
>
> Thanks
