Tyrel Datwyler <tyr...@linux.vnet.ibm.com> writes: > On 04/06/2017 09:04 PM, Michael Ellerman wrote: >> Tyrel Datwyler <tyr...@linux.vnet.ibm.com> writes: >> >>> On 04/06/2017 03:27 AM, Sachin Sant wrote: >>>> On a POWER8 LPAR running 4.11.0-rc5, a hot unplug operation on >>>> any I/O adapter results in the following warning >>>> >>>> This problem has been in the code for some time now. I had first seen this >>>> in >>>> -next tree. >>>> > > <snip> > >>>> Have attached the dmesg log from the system. Let me know if any additional >>>> information is required to help debug this problem. >>> >>> I remember you mentioning this when the issue was brought up for CPUs. I >>> assume the case is the same here where the issue is only seen with >>> adapters that were hot-added after boot (ie. hot-remove of adapter >>> present at boot doesn't trip the warning)? >> >> So who's fixing this? > > I started looking at it when Bharata submitted a patch trying to fix the > issue for CPUs, but got side tracked by other things. I suspect that > this underflow has actually been an issue for quite some time, and we > are just now becoming aware of it thanks to the recount_t patchset being > merged.
Yes I agree. Which means it might be broken in existing distros. > I'll look into it again this week. Thanks. cheers