Changeset 85514 in vbox for trunk/src/VBox/Runtime/r0drv/linux

Timestamp:

Jul 29, 2020 10:44:46 AM (4 years ago)

Author:

vboxsync

Message:

IPRT/memobj-r0drv-linux.c: Make it easier to push the W^{X semantics further back (after some testing). bugref:9801}

File:

• trunk/src/VBox/Runtime/r0drv/linux/memobj-r0drv-linux.c (modified) (5 diffs)

trunk/src/VBox/Runtime/r0drv/linux/memobj-r0drv-linux.c

@@ -51 +51 @@
 #ifndef PAGE_READONLY_EXEC
 # define PAGE_READONLY_EXEC PAGE_READONLY
+#endif
+
+/** @def IPRT_USE_ALLOC_VM_AREA_FOR_EXEC
+ * Whether we use alloc_vm_area (3.2+) for executable memory.
+ * This is a must for 5.8+, but we'll enable it for earlier kernels later. */
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 8, 0) || defined(DOXYGEN_RUNNING)
+# define IPRT_USE_ALLOC_VM_AREA_FOR_EXEC
 #endif
 
@@ -106 +113 @@
     /** Set if we've vmap'ed the memory into ring-0. */
     bool                fMappedToRing0;
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 8, 0)
+#ifdef IPRT_USE_ALLOC_VM_AREA_FOR_EXEC
     /** Return from alloc_vm_area() that we now need to use for executable
      *  memory. */
@@ -545 +552 @@
 # endif
 
-# if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 8, 0)
+# ifdef IPRT_USE_ALLOC_VM_AREA_FOR_EXEC
         if (fExecutable)
         {
@@ -613 +620 @@
 {
 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 4, 22)
-# if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 8, 0)
+# ifdef IPRT_USE_ALLOC_VM_AREA_FOR_EXEC
     if (pMemLnx->pArea)
     {
@@ -1829 +1836 @@
 DECLHIDDEN(int) rtR0MemObjNativeProtect(PRTR0MEMOBJINTERNAL pMem, size_t offSub, size_t cbSub, uint32_t fProt)
 {
-# if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 8, 0)
+# ifdef IPRT_USE_ALLOC_VM_AREA_FOR_EXEC
     /*
      * Currently only supported when we've got addresses PTEs from the kernel.