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: <[email protected]> [3.10+] Reported-by: Santosh Shilimkar <[email protected]> Tested-by: Santosh Shilimkar <[email protected]> Signed-off-by: Marc Zyngier <[email protected]> Signed-off-by: Christoffer Dall <[email protected]>
cbmeeks · Nov 17, 2013 · 40c2729 · 40c2729
1 parent 5e01dc7
commit 40c2729
Showing 1 changed file with 28 additions and 6 deletions.
diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c
@@ -307,6 +307,17 @@ static int __create_hyp_mappings(pgd_t *pgdp,
 	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 @@ static int __create_hyp_mappings(pgd_t *pgdp,
  */
 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;
 }
 
 /**