Re: [PATCH 0/5] fix radix tree multi-order iteration race

[Andrew Morton]

On Tue, 8 May 2018 11:44:24 -0600 Ross Zwisler <ross.zwisler@xxxxxxxxxxxxxxx> wrote:

> On Thu, May 03, 2018 at 01:24:25PM -0600, Ross Zwisler wrote:
> > The following series gets the radix tree test suite compiling again in
> > the current linux/master, adds a unit test which exposes a race in the
> > radix tree multi-order iteration code, and then fixes that race.
> > 
> > This race was initially hit on a v4.15 based kernel and results in a GP
> > fault.  I've described the race in detail in patches 4 and 5.
> > 
> > The fix is simple and necessary, and I think it should be merged for
> > v4.17.
> > 
> > This tree has gotten positive build confirmation from the 0-day bot,
> > passes the updated radix tree test suite, xfstests, and the original
> > test that was hitting the race with the v4.15 based kernel.
> > 
> > Ross Zwisler (5):
> >   radix tree test suite: fix mapshift build target
> >   radix tree test suite: fix compilation issue
> >   radix tree test suite: add item_delete_rcu()
> >   radix tree test suite: multi-order iteration race
> >   radix tree: fix multi-order iteration race
> > 
> >  lib/radix-tree.c                      |  6 ++--
> >  tools/include/linux/spinlock.h        |  3 +-
> >  tools/testing/radix-tree/Makefile     |  6 ++--
> >  tools/testing/radix-tree/multiorder.c | 63 +++++++++++++++++++++++++++++++++++
> >  tools/testing/radix-tree/test.c       | 19 +++++++++++
> >  tools/testing/radix-tree/test.h       |  3 ++
> >  6 files changed, 91 insertions(+), 9 deletions(-)
> > 
> > -- 
> > 2.14.3
> > 
> 
> Ping on this series.  Does anyone have any feedback?  Matthew?
> 
> I'd really like to get it into v4.17.
> 
> We can take it through the libnvdimm tree, if that's easiest.

There's a copy in Dan's linux-next tree which is missing

- The Link: tag
- The Fixes: tag
- The Reported-by
- Jan's reviewed-by
- the cc:stable tag

so I think I'll just ignore all that and send this series off to Linus next
week.