evie/android_kernel_oneplus_msm8998
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

iommu/vt-d: Don't copy translation tables if RTT bit needs to be changed

Browse source 
We can't change the RTT bit when translation is enabled, so
don't copy translation tables when we would change the bit
with our new root entry.

Tested-by: ZhenHua Li <zhen-hual@hp.com>
Tested-by: Baoquan He <bhe@redhat.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
This commit is contained in:
Joerg Roedel 2015-06-12 12:39:25 +02:00
parent a87f491890
commit c3361f2f6e
1 changed files with 11 additions and 1 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

12
drivers/iommu/intel-iommu.c
View file

@ -2934,10 +2934,20 @@ static int copy_translation_tables(struct intel_iommu *iommu)
unsigned long flags; unsigned long flags;
u64 rtaddr_reg; u64 rtaddr_reg;
int bus, ret; int bus, ret;
bool ext; bool new_ext, ext;
rtaddr_reg = dmar_readq(iommu->reg + DMAR_RTADDR_REG); rtaddr_reg = dmar_readq(iommu->reg + DMAR_RTADDR_REG);
ext = !!(rtaddr_reg & DMA_RTADDR_RTT); ext = !!(rtaddr_reg & DMA_RTADDR_RTT);
new_ext = !!ecap_ecs(iommu->ecap);
/*
* The RTT bit can only be changed when translation is disabled,
* but disabling translation means to open a window for data
* corruption. So bail out and don't copy anything if we would
* have to change the bit.
*/
if (new_ext != ext)
return -EINVAL;
old_rt_phys = rtaddr_reg & VTD_PAGE_MASK; old_rt_phys = rtaddr_reg & VTD_PAGE_MASK;
if (!old_rt_phys) if (!old_rt_phys)