[PATCH] nvme: Invalidate dcache before submitting admin cmd

[Bin Meng]

On Sun, Jun 7, 2020 at 7:22 PM Jagan Teki <jagan at amarulasolutions.com> wrote:
>
> Some architecture like ARM Cortex A53, A72 would need
> to invalidate dcache to sync the cache with the memory
> contents before flushing the cache to memory.
>
> The NVME here submitting the admin command using dma_addr
> to the memory without prior cache invalidation. This causing
> dma_addr is pointing to an invalid location in the memory
> and found the sane nvme_ctrl result.

insane?

>
> Below example shows the nvme disk scan result improper result
>
> => nvme scan
> nvme_get_info_from_identify: nn = 544502629, vwc = 100,
> sn = dev_0T, mn = `�\�, fr = t_part, mdts = 105
>
> So, invalidating the cache before submitting the admin command
> makes the dma_addr points to a valid location in the memory.
>
> Cc: Andre Przywara <andre.przywara at arm.com>
> Reported-by: Suniel Mahesh <sunil at amarulasolutions.com>
> Signed-off-by: Michael Trimarchi <michael at amarulasolutions.com>
> Signed-off-by: Jagan Teki <jagan at amarulasolutions.com>
> Tested-by: Suniel Mahesh <sunil at amarulasolutions.com>
> ---
>  drivers/nvme/nvme.c | 3 +++
>  1 file changed, 3 insertions(+)
>

Reviewed-by: Bin Meng <bmeng.cn at gmail.com>