1 files changed, 94 insertions, 0 deletions
diff --git a/libre/qemu-user-static/0007-linux-user-init_guest_space-Clean-up-control-flow-a-.patch b/libre/qemu-user-static/0007-linux-user-init_guest_space-Clean-up-control-flow-a-.patch
new file mode 100644
index 000000000..59be04cf9
--- /dev/null
+++ b/libre/qemu-user-static/0007-linux-user-init_guest_space-Clean-up-control-flow-a-.patch
@@ -0,0 +1,94 @@
+From dbbba45fa37da85ac213fbbe1f7eab3e1de74b41 Mon Sep 17 00:00:00 2001
+From: Luke Shumaker <lukeshu@parabola.nu>
+Date: Wed, 27 Dec 2017 21:17:52 -0500
+Subject: [PATCH 07/10] linux-user: init_guest_space: Clean up control flow a
+ bit
+
+Instead of doing
+
+        if (check1) {
+            if (check2) {
+               success;
+            }
+        }
+
+        retry;
+
+Do a clearer
+
+        if (!check1) {
+           goto try_again;
+        }
+
+        if (!check2) {
+           goto try_again;
+        }
+
+        success;
+
+    try_again:
+        retry;
+
+Besides being clearer, this makes it easier to insert more checks that
+need to trigger a retry on check failure, or rearrange them, or anything
+like that.
+
+Because some indentation is changing, "ignore space change" may be useful
+for viewing this patch.
+
+Signed-off-by: Luke Shumaker <lukeshu@parabola.nu>
+---
+ linux-user/elfload.c | 34 +++++++++++++++++++---------------
+ 1 file changed, 19 insertions(+), 15 deletions(-)
+
+diff --git a/linux-user/elfload.c b/linux-user/elfload.c
+index b560f5d6fe..5c0ad65611 100644
+--- a/linux-user/elfload.c
++++ b/linux-user/elfload.c
+@@ -1906,24 +1906,28 @@ unsigned long init_guest_space(unsigned long host_start,
+         }
+ 
+         /* Check to see if the address is valid.  */
+-        if (!host_start || aligned_start == current_start) {
++        if (host_start && aligned_start != current_start) {
++            goto try_again;
++        }
++
+ #if defined(TARGET_ARM) && !defined(TARGET_AARCH64)
+-            /* On 32-bit ARM, we need to also be able to map the commpage.  */
+-            int valid = init_guest_commpage(aligned_start - guest_start,
+-                                            aligned_size + guest_start);
+-            if (valid == 1) {
+-                break;
+-            } else if (valid == -1) {
+-                munmap((void *)real_start, real_size);
+-                return (unsigned long)-1;
+-            }
+-            /* valid == 0, so try again. */
+-#else
+-            /* On other architectures, whatever we have here is fine.  */
+-            break;
+-#endif
++        /* On 32-bit ARM, we need to also be able to map the commpage.  */
++        int valid = init_guest_commpage(aligned_start - guest_start,
++                                        aligned_size + guest_start);
++        if (valid == -1) {
++            munmap((void *)real_start, real_size);
++            return (unsigned long)-1;
++        } else if (valid == -1) {
++            goto try_again;
+         }
++#endif
++
++        /* If nothing has said `return -1` or `goto try_again` yet,
++         * then the address we have is good.
++         */
++        break;
+ 
++    try_again:
+         /* That address didn't work.  Unmap and try a different one.
+          * The address the host picked because is typically right at
+          * the top of the host address space and leaves the guest with
+-- 
+2.15.1
+