diff options
| author | Ashok Raj | 2017-08-08 13:29:27 -0700 |
|---|---|---|
| committer | Joerg Roedel | 2017-08-30 17:48:18 +0200 |
| commit | 9d8c3af31607819a61011d746e861b8096ac9761 (patch) | |
| tree | c7ae280f333a27f154fa52168ad07293fbef3d2b /drivers | |
| parent | bc24c57159fac5f7e8df22ce3bc8069578684763 (diff) | |
iommu/vt-d: IOMMU Page Request needs to check if address is canonical.
Page Request from devices that support device-tlb would request translation
to pre-cache them in device to avoid overhead of IOMMU lookups.
IOMMU needs to check for canonicallity of the address before performing
page-fault processing.
To: Joerg Roedel <joro@8bytes.org>
To: linux-kernel@vger.kernel.org>
Cc: iommu@lists.linux-foundation.org
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Jacob Pan <jacob.jun.pan@intel.com>
Cc: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Ashok Raj <ashok.raj@intel.com>
Reported-by: Sudeep Dutt <sudeep.dutt@intel.com>
Acked-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/iommu/intel-svm.c | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/drivers/iommu/intel-svm.c b/drivers/iommu/intel-svm.c index f167c0d84ebf..0c9f0773601d 100644 --- a/drivers/iommu/intel-svm.c +++ b/drivers/iommu/intel-svm.c @@ -24,6 +24,7 @@ #include <linux/pci-ats.h> #include <linux/dmar.h> #include <linux/interrupt.h> +#include <asm/page.h> static irqreturn_t prq_event_thread(int irq, void *d); @@ -555,6 +556,14 @@ static bool access_error(struct vm_area_struct *vma, struct page_req_dsc *req) return (requested & ~vma->vm_flags) != 0; } +static bool is_canonical_address(u64 addr) +{ + int shift = 64 - (__VIRTUAL_MASK_SHIFT + 1); + long saddr = (long) addr; + + return (((saddr << shift) >> shift) == saddr); +} + static irqreturn_t prq_event_thread(int irq, void *d) { struct intel_iommu *iommu = d; @@ -612,6 +621,11 @@ static irqreturn_t prq_event_thread(int irq, void *d) /* If the mm is already defunct, don't handle faults. */ if (!mmget_not_zero(svm->mm)) goto bad_req; + + /* If address is not canonical, return invalid response */ + if (!is_canonical_address(address)) + goto bad_req; + down_read(&svm->mm->mmap_sem); vma = find_extend_vma(svm->mm, address); if (!vma || address < vma->vm_start) |