Re: [PATCH 4.4] nvme-pci: initialize queue memory before interrupts

From: Greg Kroah-Hartman
Date: Thu Jul 05 2018 - 12:55:36 EST


On Tue, Jun 19, 2018 at 06:23:06PM +0100, Ben Hutchings wrote:
> From: Keith Busch <keith.busch@xxxxxxxxx>
>
> commit 161b8be2bd6abad250d4b3f674bdd5480f15beeb upstream.
>
> A spurious interrupt before the nvme driver has initialized the completion
> queue may inadvertently cause the driver to believe it has a completion
> to process. This may result in a NULL dereference since the nvmeq's tags
> are not set at this point.
>
> The patch initializes the host's CQ memory so that a spurious interrupt
> isn't mistaken for a real completion.
>
> Signed-off-by: Keith Busch <keith.busch@xxxxxxxxx>
> Reviewed-by: Johannes Thumshirn <jthumshirn@xxxxxxx>
> Signed-off-by: Christoph Hellwig <hch@xxxxxx>
> [bwh: Backported to 4.4: adjust context]
> Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
> ---
> drivers/nvme/host/pci.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)

Now applied, thanks.

greg k-h