This is a note to let you know that I've just added the patch titled infiniband: fix race condition between infiniband mlx4, mlx5 driver and core dumping to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: infiniband-fix-race-condition-between-infiniband-mlx4-mlx5-driver-and-core-dumping.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From akaher@xxxxxxxxxx Mon Aug 5 08:01:12 2019 From: Ajay Kaher <akaher@xxxxxxxxxx> Date: Sun, 4 Aug 2019 09:29:26 +0530 Subject: infiniband: fix race condition between infiniband mlx4, mlx5 driver and core dumping To: <aarcange@xxxxxxxxxx>, <jannh@xxxxxxxxxx>, <oleg@xxxxxxxxxx>, <peterx@xxxxxxxxxx>, <rppt@xxxxxxxxxxxxx>, <jgg@xxxxxxxxxxxx>, <mhocko@xxxxxxxx> Cc: srinidhir@xxxxxxxxxx, linux-kernel@xxxxxxxxxxxxxxx, linux-mm@xxxxxxxxx, amakhalov@xxxxxxxxxx, sean.hefty@xxxxxxxxx, srivatsa@xxxxxxxxxxxxx, srivatsab@xxxxxxxxxx, devel@xxxxxxxxxxxxxxxxxxxx, linux-rdma@xxxxxxxxxxxxxxx, bvikas@xxxxxxxxxx, dledford@xxxxxxxxxx, akaher@xxxxxxxxxx, riandrews@xxxxxxxxxxx, hal.rosenstock@xxxxxxxxx, vsirnapalli@xxxxxxxxxx, leonro@xxxxxxxxxxxx, jglisse@xxxxxxxxxx, viro@xxxxxxxxxxxxxxxxxx, gregkh@xxxxxxxxxxxxxxxxxxx, yishaih@xxxxxxxxxxxx, matanb@xxxxxxxxxxxx, stable@xxxxxxxxxxxxxxx, arve@xxxxxxxxxxx, linux-fsdevel@xxxxxxxxxxxxxxx, akpm@xxxxxxxxxxxxxxxxxxxx, torvalds@xxxxxxxxxxxxxxxxxxxx, mike.kravetz@xxxxxxxxxx Message-ID: <1564891168-30016-2-git-send-email-akaher@xxxxxxxxxx> From: Ajay Kaher <akaher@xxxxxxxxxx> This patch is the extension of following upstream commit to fix the race condition between get_task_mm() and core dumping for IB->mlx4 and IB->mlx5 drivers: commit 04f5866e41fb ("coredump: fix race condition between mmget_not_zero()/get_task_mm() and core dumping")' Thanks to Jason for pointing this. Signed-off-by: Ajay Kaher <akaher@xxxxxxxxxx> Reviewed-by: Jason Gunthorpe <jgg@xxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/infiniband/hw/mlx4/main.c | 4 +++- drivers/infiniband/hw/mlx5/main.c | 3 +++ 2 files changed, 6 insertions(+), 1 deletion(-) --- a/drivers/infiniband/hw/mlx4/main.c +++ b/drivers/infiniband/hw/mlx4/main.c @@ -1172,6 +1172,8 @@ static void mlx4_ib_disassociate_ucontex * mlx4_ib_vma_close(). */ down_write(&owning_mm->mmap_sem); + if (!mmget_still_valid(owning_mm)) + goto skip_mm; for (i = 0; i < HW_BAR_COUNT; i++) { vma = context->hw_bar_info[i].vma; if (!vma) @@ -1190,7 +1192,7 @@ static void mlx4_ib_disassociate_ucontex /* context going to be destroyed, should not access ops any more */ context->hw_bar_info[i].vma->vm_ops = NULL; } - +skip_mm: up_write(&owning_mm->mmap_sem); mmput(owning_mm); put_task_struct(owning_process); --- a/drivers/infiniband/hw/mlx5/main.c +++ b/drivers/infiniband/hw/mlx5/main.c @@ -1307,6 +1307,8 @@ static void mlx5_ib_disassociate_ucontex * mlx5_ib_vma_close. */ down_write(&owning_mm->mmap_sem); + if (!mmget_still_valid(owning_mm)) + goto skip_mm; list_for_each_entry_safe(vma_private, n, &context->vma_private_list, list) { vma = vma_private->vma; @@ -1321,6 +1323,7 @@ static void mlx5_ib_disassociate_ucontex list_del(&vma_private->list); kfree(vma_private); } +skip_mm: up_write(&owning_mm->mmap_sem); mmput(owning_mm); put_task_struct(owning_process); Patches currently in stable-queue which might be from akaher@xxxxxxxxxx are queue-4.9/infiniband-fix-race-condition-between-infiniband-mlx4-mlx5-driver-and-core-dumping.patch queue-4.9/coredump-fix-race-condition-between-collapse_huge_page-and-core-dumping.patch queue-4.9/coredump-fix-race-condition-between-mmget_not_zero-get_task_mm-and-core-dumping.patch