> On Aug 8, 2016, at 3:59 PM, bfields@xxxxxxxxxxxx wrote: > > On Mon, Aug 08, 2016 at 02:59:35PM -0400, Chuck Lever wrote: >> This series passes light testing in my lab. If it looks good I will >> pass it along to Alexey to confirm it closes the race. >> >> To aid distributors and stable kernel maintainers, wondering if a >> Fixes: tag should be added. Alexey first observed this issue in v4.1 >> kernels (UEK4). But looks like the race could have been introduced >> as early as v3.17. Maybe this one? > > The other reason we didn't see this till now might be client-side > changes (maybe b4019c0e219b "NFSv4.1: Allow parallel LOCK/LOCKU > calls"?). (Not trying to dodge responsibility for a server-side bug > here, but that might still be useful information for the changelog (not > the Fixes: line) if it's correct.) I asked Alexey to test as far back as v3.19, where I think the LOCK parallelism was added. I need to get some clarification of his test results; one set of test runs reproduced the race, and a second set of test runs did not. > --b. > >> >> commit fc5a96c3b70d00c863f69ff4ea7f5dfddbcbc0d8 >> Author: Jeff Layton <jlayton@xxxxxxxxxxxxxxx> >> Date: Tue Jul 29 21:34:40 2014 -0400 >> >> nfsd: close potential race in nfsd4_free_stateid >> >> There have been a lot of changes since then. It's hard to say if the >> race can be attributed to a single commit. >> >> >> Changes since v2: >> - Move NFS4_LOCK_STID arm into a helper, for clarity >> - Add more detail to patch description >> - Add Jeff's patch to fix similar race in nfsd4_lock >> >> Changes since v1: >> - Use s->sc_count to preserve stateid while cl_lock is dropped >> >> --- >> >> Chuck Lever (1): >> nfsd: Fix race between FREE_STATEID and LOCK >> >> Jeff Layton (1): >> nfsd: don't return an unhashed lock stateid after taking mutex >> >> >> fs/nfsd/nfs4state.c | 65 ++++++++++++++++++++++++++++++++++++++------------- >> 1 file changed, 48 insertions(+), 17 deletions(-) >> >> -- >> Chuck Lever >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-nfs" in >> the body of a message to majordomo@xxxxxxxxxxxxxxx >> More majordomo info at http://vger.kernel.org/majordomo-info.html -- Chuck Lever -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
