path: root/drivers/infiniband/sw
diff options
authorYishai Hadas <yishaih@mellanox.com>2019-08-05 11:30:10 +0300
committerJason Gunthorpe <jgg@mellanox.com>2019-08-07 15:36:43 -0300
commitf591822c3cf314442819486f45ff7dc1f690e0c0 (patch)
treea864901af6ec08887925d344e08800d98a30c69f /drivers/infiniband/sw
parentLinux 5.3-rc3 (diff)
IB/mlx5: Fix implicit MR release flow
Once implicit MR is being called to be released by ib_umem_notifier_release() its leaves were marked as "dying". However, when dereg_mr()->mlx5_ib_free_implicit_mr()->mr_leaf_free() is called, it skips running the mr_leaf_free_action (i.e. umem_odp->work) when those leaves were marked as "dying". As such ib_umem_release() for the leaves won't be called and their MRs will be leaked as well. When an application exits/killed without calling dereg_mr we might hit the above flow. This fatal scenario is reported by WARN_ON() upon mlx5_ib_dealloc_ucontext() as ibcontext->per_mm_list is not empty, the call trace can be seen below. Originally the "dying" mark as part of ib_umem_notifier_release() was introduced to prevent pagefault_mr() from returning a success response once this happened. However, we already have today the completion mechanism so no need for that in those flows any more. Even in case a success response will be returned the firmware will not find the pages and an error will be returned in the following call as a released mm will cause ib_umem_odp_map_dma_pages() to permanently fail mmget_not_zero(). Fix the above issue by dropping the "dying" from the above flows. The other flows that are using "dying" are still needed it for their synchronization purposes. WARNING: CPU: 1 PID: 7218 at drivers/infiniband/hw/mlx5/main.c:2004 mlx5_ib_dealloc_ucontext+0x84/0x90 [mlx5_ib] CPU: 1 PID: 7218 Comm: ibv_rc_pingpong Tainted: G E 5.2.0-rc6+ #13 Call Trace: uverbs_destroy_ufile_hw+0xb5/0x120 [ib_uverbs] ib_uverbs_close+0x1f/0x80 [ib_uverbs] __fput+0xbe/0x250 task_work_run+0x88/0xa0 do_exit+0x2cb/0xc30 ? __fput+0x14b/0x250 do_group_exit+0x39/0xb0 get_signal+0x191/0x920 ? _raw_spin_unlock_bh+0xa/0x20 ? inet_csk_accept+0x229/0x2f0 do_signal+0x36/0x5e0 ? put_unused_fd+0x5b/0x70 ? __sys_accept4+0x1a6/0x1e0 ? inet_hash+0x35/0x40 ? release_sock+0x43/0x90 ? _raw_spin_unlock_bh+0xa/0x20 ? inet_listen+0x9f/0x120 exit_to_usermode_loop+0x5c/0xc6 do_syscall_64+0x182/0x1b0 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Fixes: 81713d3788d2 ("IB/mlx5: Add implicit MR support") Link: https://lore.kernel.org/r/20190805083010.21777-1-leon@kernel.org Signed-off-by: Yishai Hadas <yishaih@mellanox.com> Reviewed-by: Artemy Kovalyov <artemyko@mellanox.com> Signed-off-by: Leon Romanovsky <leonro@mellanox.com> Reviewed-by: Jason Gunthorpe <jgg@mellanox.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Diffstat (limited to 'drivers/infiniband/sw')
0 files changed, 0 insertions, 0 deletions