Re: [PATCH 1/3] platform/x86: ISST: Check for unaligned mmio address

From: Hans de Goede
Date: Mon Dec 07 2020 - 09:18:32 EST


Hi,

On 12/4/20 2:57 AM, Srinivas Pandruvada wrote:
> The address should be aligned to 4 byte boundary. So send an error for
> unaligned address.
>
> Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@xxxxxxxxxxxxxxx>

Thank you for your patch-series.

One thing which still seems to be missing after this series is a check for
attempting to read/write the hole between the 2 ranges. Can you please
provide a follow-up patch adding such a check?

###

I've applied the series to my review-hans branch:
https://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86.git/log/?h=review-hans

Note it will show up in my review-hans branch once I've pushed my
local branch there, which might take a while.

Once I've run some tests on this branch the patches there will be
added to the platform-drivers-x86/for-next branch and eventually
will be included in the pdx86 pull-request to Linus for the next
merge-window.

Regards,

Hans


> ---
> drivers/platform/x86/intel_speed_select_if/isst_if_mmio.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/drivers/platform/x86/intel_speed_select_if/isst_if_mmio.c b/drivers/platform/x86/intel_speed_select_if/isst_if_mmio.c
> index aa17fd7817f8..e7e9808a1aed 100644
> --- a/drivers/platform/x86/intel_speed_select_if/isst_if_mmio.c
> +++ b/drivers/platform/x86/intel_speed_select_if/isst_if_mmio.c
> @@ -42,6 +42,9 @@ static long isst_if_mmio_rd_wr(u8 *cmd_ptr, int *write_only, int resume)
> if (io_reg->reg < 0x04 || io_reg->reg > 0xD0)
> return -EINVAL;
>
> + if (io_reg->reg % 4)
> + return -EINVAL;
> +
> if (io_reg->read_write && !capable(CAP_SYS_ADMIN))
> return -EPERM;
>
>