RE: Userspace woes with 5.1.5 due to TIPC

[Jon Maloy]

> -----Original Message-----
> From: Ying Xue <ying.xue@xxxxxxxxxxxxx>
> Sent: 30-May-19 20:41
> To: Mihai Moldovan <ionic@xxxxxxxx>; Jon Maloy
> <jon.maloy@xxxxxxxxxxxx>; linux-kernel@xxxxxxxxxxxxxxx
> Subject: Re: Userspace woes with 5.1.5 due to TIPC
> 
> On 5/31/19 4:47 AM, Mihai Moldovan wrote:
> > * On 5/30/19 9:51 PM, Jon Maloy wrote:
> >> Make sure the following three commits are present in TIPC *after* the
> offending commit:
> >>
> >> commit 532b0f7ece4c "tipc: fix modprobe tipc failed after switch order of
> device registration"
> >
> > This *is* the offending commit, as far as I understand. Merely rebased
> > in linux-stable, and hence having a different SHA, but mentioning the
> > original SHA (i.e., 532b0f7ece4c) in its commit message.
> >
> >
> >> Since that patch one was flawed it had to be reverted:
> >> commit 5593530e5694  ""Revert tipc: fix modprobe tipc failed after switch
> order of device registration"
> >>
> >> It was then replaced with this one:
> >> commit 526f5b851a96 "tipc: fix modprobe tipc failed after switch order of
> device registration"
> >
> > Okay, these two are not part of 5.1.5. I've backported them (and only
> > these two) to 5.1.5 and the issue(s) seem to be gone. Definitely
> > something that should be backported to/included in 5.1.6.
> >
> >
> > Thanks for pointing all that out! Unfortunately I didn't add anything
> > useful but noise, since you obviously already knew, that this commit
> > was broken. I'd urge Greg to release a new stable version including
> > the fixes soon, if possible, though, for not being able to start/use
> > userspace browsers sounds like a pretty bad regression to me.
> >
> 
> Not only commit 526f5b851a96 )("tipc: fix modprobe tipc failed after switch
> order of device registration") has to be reverted, but also I found commit
> 7e27e8d6130c ("tipc: switch order of device registration to fix a crash")
> introduced a serious regression which makes tipc internal topology service
> server failed to be created.

This was the very reason the broken patch was introduced. AFAIK there is no problem after the corrected version of that patch was applied.

///jon

> 
> Today I will fix it with the following approaches:
> 1. Revert commit 7e27e8d6130c ("tipc: switch order of device registration to
> fix a crash") 2. Use another method to solve the problem that commit
> 7e27e8d6130c tries to fix.
> 
> Thanks,
> Ying
> 
> >
> >
> > Mihai
> >