On Fri, Oct 4, 2019 at 8:11 PM Alexey Kardashevskiy <aik@xxxxxxxxx> wrote: > > > > On 04/10/2019 23:46, Catalin Marinas wrote: > > In case of an error (e.g. memory pool too small), kmemleak disables > > itself and cleans up the already allocated metadata objects. However, if > > this happens early before the RCU callback mechanism is available, > > put_object() skips call_rcu() and frees the object directly. This is not > > safe with the RCU list traversal in __kmemleak_do_cleanup(). > > > > Change the list traversal in __kmemleak_do_cleanup() to > > list_for_each_entry_safe() and remove the rcu_read_{lock,unlock} since > > the kmemleak is already disabled at this point. In addition, avoid an > > unnecessary metadata object rb-tree look-up since it already has the > > struct kmemleak_object pointer. > > > > Fixes: c5665868183f ("mm: kmemleak: use the memory pool for early allocations") > > Reported-by: Alexey Kardashevskiy <aik@xxxxxxxxx> > > Reported-by: Marc Dionne <marc.c.dionne@xxxxxxxxx> > > Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> > > Signed-off-by: Catalin Marinas <catalin.marinas@xxxxxxx> > > > Tested-by: Alexey Kardashevskiy <aik@xxxxxxxxx> Tested-by: Song Liu <songliubraving@xxxxxx> This fixes my vm, which could not boot with 5.4-rc3. Thanks, Song