Re: [PATCH v2] iommu/vt-d: Check VT-d RMRR region in BIOS is reported as reserved

From: Joerg Roedel
Date: Mon Nov 11 2019 - 10:06:40 EST


On Thu, Oct 17, 2019 at 04:39:19AM -0700, Yian Chen wrote:
> VT-d RMRR (Reserved Memory Region Reporting) regions are reserved
> for device use only and should not be part of allocable memory pool of OS.
>
> BIOS e820_table reports complete memory map to OS, including OS usable
> memory ranges and BIOS reserved memory ranges etc.
>
> x86 BIOS may not be trusted to include RMRR regions as reserved type
> of memory in its e820 memory map, hence validate every RMRR entry
> with the e820 memory map to make sure the RMRR regions will not be
> used by OS for any other purposes.
>
> ia64 EFI is working fine so implement RMRR validation as a dummy function
>
> Reviewed-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
> Reviewed-by: Sohil Mehta <sohil.mehta@xxxxxxxxx>
> Signed-off-by: Yian Chen <yian.chen@xxxxxxxxx>
> ---
> v2:
> - return -EINVAL instead of -EFAULT when there is an error
> ---
> arch/ia64/include/asm/iommu.h | 5 +++++
> arch/x86/include/asm/iommu.h | 18 ++++++++++++++++++
> drivers/iommu/intel-iommu.c | 8 +++++++-
> 3 files changed, 30 insertions(+), 1 deletion(-)

Applied, thanks.