Patch "IB/mlx4: Change vma from shared to private" has been added to the 4.4-stable tree

Patch "IB/mlx4: Change vma from shared to private" has been added to the 4.4-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    IB/mlx4: Change vma from shared to private

to the 4.4-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:
     ib-mlx4-change-vma-from-shared-to-private.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From foo@baz Thu Mar 22 14:57:32 CET 2018
From: Maor Gottlieb <maorg@mellanox.com>
Date: Wed, 29 Mar 2017 06:03:01 +0300
Subject: IB/mlx4: Change vma from shared to private

From: Maor Gottlieb <maorg@mellanox.com>


[ Upstream commit ca37a664a8e4e9988b220988ceb4d79e3316f195 ]

Anonymous VMA (->vm_ops == NULL) cannot be shared, otherwise
it would lead to SIGBUS.

Remove the shared flags from the vma after we change it to be
anonymous.

This is easily reproduced by doing modprobe -r while running a
user-space application such as raw_ethernet_bw.

Fixes: ae184ddeca5db ('IB/mlx4_ib: Disassociate support')
Signed-off-by: Maor Gottlieb <maorg@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/infiniband/hw/mlx4/main.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/drivers/infiniband/hw/mlx4/main.c
+++ b/drivers/infiniband/hw/mlx4/main.c
@@ -1055,6 +1055,8 @@ static void mlx4_ib_disassociate_ucontex
 			BUG_ON(1);
 		}
 
+		context->hw_bar_info[i].vma->vm_flags &=
+			~(VM_SHARED | VM_MAYSHARE);
 		/* context going to be destroyed, should not access ops any more */
 		context->hw_bar_info[i].vma->vm_ops = NULL;
 	}


Patches currently in stable-queue which might be from maorg@mellanox.com are

queue-4.4/ib-mlx4-change-vma-from-shared-to-private.patch
queue-4.4/ib-mlx4-take-write-semaphore-when-changing-the-vma-struct.patch