If we have to drop the seqcount & rcu lock to perform a krealloc, we have to restart the loop. In doing so, be careful not to lose track of the already acquired exclusive fence.
Fixes: fedf54132d24 ("dma-buf: Restart reservation_object_get_fences_rcu() after writes") #v4.10 Signed-off-by: Chris Wilson <ch...@chris-wilson.co.uk> Cc: Daniel Vetter <daniel.vet...@ffwll.ch> Cc: Maarten Lankhorst <maarten.lankho...@linux.intel.com> Cc: Christian König <christian.koe...@amd.com> Cc: Alex Deucher <alexander.deuc...@amd.com> Cc: Sumit Semwal <sumit.sem...@linaro.org> Cc: sta...@vger.kernel.org Reviewed-by: Christian König <christian.koe...@amd.com> --- This, this is v2. Not the old branch; remember to check the git send-email before hitting enter. -Chris --- drivers/dma-buf/reservation.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/dma-buf/reservation.c b/drivers/dma-buf/reservation.c index 4d32e2c67862..4447e13d1e89 100644 --- a/drivers/dma-buf/reservation.c +++ b/drivers/dma-buf/reservation.c @@ -365,6 +365,10 @@ int reservation_object_get_fences_rcu(struct reservation_object *obj, GFP_NOWAIT | __GFP_NOWARN); if (!nshared) { rcu_read_unlock(); + + dma_fence_put(fence_excl); + fence_excl = NULL; + nshared = krealloc(shared, sz, GFP_KERNEL); if (nshared) { shared = nshared; -- 2.20.1 _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx