arm/arm64: KVM: Fix hyp mappings of vmalloc regions

Using virt_to_phys on percpu mappings is horribly wrong as it may be
backed by vmalloc.  Introduce kvm_kaddr_to_phys which translates both
types of valid kernel addresses to the corresponding physical address.

At the same time resolves a typing issue where we were storing the
physical address as a 32 bit unsigned long (on arm), truncating the
physical address for addresses above the 4GB limit.  This caused
breakage on Keystone.

Cc: <stable@vger.kernel.org>	[3.10+]
Reported-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>

1 files changed, 28 insertions, 6 deletions

diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c
index b0de86b56c13..cb79a5dd6d96 100644
--- a/arch/arm/kvm/mmu.c
+++ b/arch/arm/kvm/mmu.c
@@ -307,6 +307,17 @@ out:
         return err;
 }
 
+static phys_addr_t kvm_kaddr_to_phys(void *kaddr)
+{
+        if (!is_vmalloc_addr(kaddr)) {
+                BUG_ON(!virt_addr_valid(kaddr));
+                return __pa(kaddr);
+        } else {
+                return page_to_phys(vmalloc_to_page(kaddr)) +
+                       offset_in_page(kaddr);
+        }
+}
+
 /**
  * create_hyp_mappings - duplicate a kernel virtual address range in Hyp mode
  * @from:       The virtual kernel start address of the range
@@ -318,16 +329,27 @@ out:
  */
 int create_hyp_mappings(void *from, void *to)
 {
-        unsigned long phys_addr = virt_to_phys(from);
+        phys_addr_t phys_addr;
+        unsigned long virt_addr;
         unsigned long start = KERN_TO_HYP((unsigned long)from);
         unsigned long end = KERN_TO_HYP((unsigned long)to);
 
-        /* Check for a valid kernel memory mapping */
-        if (!virt_addr_valid(from) || !virt_addr_valid(to - 1))
-                return -EINVAL;
+        start = start & PAGE_MASK;
+        end = PAGE_ALIGN(end);
 
-        return __create_hyp_mappings(hyp_pgd, start, end,
-                                     __phys_to_pfn(phys_addr), PAGE_HYP);
+        for (virt_addr = start; virt_addr < end; virt_addr += PAGE_SIZE) {
+                int err;
+
+                phys_addr = kvm_kaddr_to_phys(from + virt_addr - start);
+                err = __create_hyp_mappings(hyp_pgd, virt_addr,
+                                            virt_addr + PAGE_SIZE,
+                                            __phys_to_pfn(phys_addr),
+                                            PAGE_HYP);
+                if (err)
+                        return err;
+        }
+
+        return 0;
 }
 
 /**