Revert "Revert "mm/rmap: Fix anon_vma->degree ambiguity leading to double-reuse""
This reverts commit 4f35cec76058557d9eaec0d501d03c7657eb56b4 and does so
in an abi-safe way.
This is done by adding the new fields only to the end of the structure
and this structure is only passed around to other functions as a
pointer, the internal structure layout is only touched by the core
kernel, so adding it to the end is safe.
Updated the ABI using The Button:
Leaf changes summary: 1 artifact changed
Changed leaf types summary: 1 leaf type changed
Removed/Changed/Added functions summary: 0 Removed, 0 Changed, 0 Added function
Removed/Changed/Added variables summary: 0 Removed, 0 Changed, 0 Added variable
'struct anon_vma at rmap.h:33:1' changed:
type size changed from 832 to 960 (in bits)
2 data member insertions:
'unsigned long int num_children', at offset 832 (in bits) at rmap.h:74:1
'unsigned long int num_active_vmas', at offset 896 (in bits) at rmap.h:76:1
5406 impacted interfaces
Bug: 260678056
Bug: 253167854
Change-Id: Ib1d45625cbc2e0b21330ca3dc2aa7aff34666d31
Signed-off-by: Lee Jones <joneslee@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
(cherry picked from commit 33b1e2eb04dc5a5738a9e790e6bcce4d9e369c42)
diff --git a/android/abi_gki_aarch64.xml b/android/abi_gki_aarch64.xml
index 0258887..f17e313 100644
--- a/android/abi_gki_aarch64.xml
+++ b/android/abi_gki_aarch64.xml
@@ -12767,7 +12767,7 @@
<return type-id='95e97e5e'/>
</function-type>
<pointer-type-def type-id='2b7b3388' size-in-bits='64' id='14f24806'/>
- <class-decl name='anon_vma' size-in-bits='832' is-struct='yes' visibility='default' filepath='include/linux/rmap.h' line='29' column='1' id='14f332cc'>
+ <class-decl name='anon_vma' size-in-bits='960' is-struct='yes' visibility='default' filepath='include/linux/rmap.h' line='29' column='1' id='14f332cc'>
<data-member access='public' layout-offset-in-bits='0'>
<var-decl name='root' type-id='a8f86cda' visibility='default' filepath='include/linux/rmap.h' line='30' column='1'/>
</data-member>
@@ -12778,13 +12778,19 @@
<var-decl name='refcount' type-id='49178f86' visibility='default' filepath='include/linux/rmap.h' line='39' column='1'/>
</data-member>
<data-member access='public' layout-offset-in-bits='608'>
- <var-decl name='degree' type-id='f0981eeb' visibility='default' filepath='include/linux/rmap.h' line='47' column='1'/>
+ <var-decl name='degree' type-id='f0981eeb' visibility='default' filepath='include/linux/rmap.h' line='41' column='1'/>
</data-member>
<data-member access='public' layout-offset-in-bits='640'>
- <var-decl name='parent' type-id='a8f86cda' visibility='default' filepath='include/linux/rmap.h' line='49' column='1'/>
+ <var-decl name='parent' type-id='a8f86cda' visibility='default' filepath='include/linux/rmap.h' line='43' column='1'/>
</data-member>
<data-member access='public' layout-offset-in-bits='704'>
- <var-decl name='rb_root' type-id='6fe1603d' visibility='default' filepath='include/linux/rmap.h' line='61' column='1'/>
+ <var-decl name='rb_root' type-id='6fe1603d' visibility='default' filepath='include/linux/rmap.h' line='55' column='1'/>
+ </data-member>
+ <data-member access='public' layout-offset-in-bits='832'>
+ <var-decl name='num_children' type-id='7359adad' visibility='default' filepath='include/linux/rmap.h' line='70' column='1'/>
+ </data-member>
+ <data-member access='public' layout-offset-in-bits='896'>
+ <var-decl name='num_active_vmas' type-id='7359adad' visibility='default' filepath='include/linux/rmap.h' line='72' column='1'/>
</data-member>
</class-decl>
<pointer-type-def type-id='031a4ff0' size-in-bits='64' id='1507ee2a'/>
@@ -22021,7 +22027,7 @@
<parameter type-id='855e3679'/>
<return type-id='95e97e5e'/>
</function-type>
- <typedef-decl name='va_list' type-id='7f896fb4' filepath='prebuilts/clang/host/linux-x86/clang-r450784e/lib64/clang/14.0.7/include/stdarg.h' line='14' column='1' id='2aee9912'/>
+ <typedef-decl name='va_list' type-id='7f896fb4' filepath='/buildbot/src/android/common-android13-5.10-2023-01/prebuilts/clang/host/linux-x86/clang-r450784e/lib64/clang/14.0.7/include/stdarg.h' line='14' column='1' id='2aee9912'/>
<class-decl name='transport_container' size-in-bits='832' is-struct='yes' visibility='default' filepath='include/linux/transport_class.h' line='56' column='1' id='2af4292a'>
<data-member access='public' layout-offset-in-bits='0'>
<var-decl name='ac' type-id='52bea74f' visibility='default' filepath='include/linux/transport_class.h' line='57' column='1'/>
@@ -139299,9 +139305,9 @@
<parameter type-id='e5411c2c' name='function' filepath='drivers/usb/gadget/composite.c' line='315' column='1'/>
<return type-id='95e97e5e'/>
</function-decl>
- <function-decl name='usb_add_gadget_udc' mangled-name='usb_add_gadget_udc' filepath='drivers/usb/gadget/udc/core.c' line='1419' column='1' visibility='default' binding='global' size-in-bits='64' elf-symbol-id='usb_add_gadget_udc'>
- <parameter type-id='fa0b179b' name='parent' filepath='drivers/usb/gadget/udc/core.c' line='1419' column='1'/>
- <parameter type-id='49a58c0c' name='gadget' filepath='drivers/usb/gadget/udc/core.c' line='1419' column='1'/>
+ <function-decl name='usb_add_gadget_udc' mangled-name='usb_add_gadget_udc' filepath='drivers/usb/gadget/udc/core.c' line='1420' column='1' visibility='default' binding='global' size-in-bits='64' elf-symbol-id='usb_add_gadget_udc'>
+ <parameter type-id='fa0b179b' name='parent' filepath='drivers/usb/gadget/udc/core.c' line='1420' column='1'/>
+ <parameter type-id='49a58c0c' name='gadget' filepath='drivers/usb/gadget/udc/core.c' line='1420' column='1'/>
<return type-id='95e97e5e'/>
</function-decl>
<function-decl name='usb_add_hcd' mangled-name='usb_add_hcd' filepath='drivers/usb/core/hcd.c' line='2659' column='1' visibility='default' binding='global' size-in-bits='64' elf-symbol-id='usb_add_hcd'>
@@ -139419,8 +139425,8 @@
<return type-id='fc4f83c1'/>
</function-decl>
<var-decl name='usb_debug_root' type-id='27675065' mangled-name='usb_debug_root' visibility='default' filepath='drivers/usb/common/common.c' line='396' column='1' elf-symbol-id='usb_debug_root'/>
- <function-decl name='usb_del_gadget_udc' mangled-name='usb_del_gadget_udc' filepath='drivers/usb/gadget/udc/core.c' line='1484' column='1' visibility='default' binding='global' size-in-bits='64' elf-symbol-id='usb_del_gadget_udc'>
- <parameter type-id='49a58c0c' name='gadget' filepath='drivers/usb/gadget/udc/core.c' line='1484' column='1'/>
+ <function-decl name='usb_del_gadget_udc' mangled-name='usb_del_gadget_udc' filepath='drivers/usb/gadget/udc/core.c' line='1485' column='1' visibility='default' binding='global' size-in-bits='64' elf-symbol-id='usb_del_gadget_udc'>
+ <parameter type-id='49a58c0c' name='gadget' filepath='drivers/usb/gadget/udc/core.c' line='1485' column='1'/>
<return type-id='48b5725f'/>
</function-decl>
<function-decl name='usb_deregister' mangled-name='usb_deregister' filepath='drivers/usb/core/driver.c' line='1100' column='1' visibility='default' binding='global' size-in-bits='64' elf-symbol-id='usb_deregister'>
@@ -139541,42 +139547,42 @@
<parameter type-id='f666bcc1' name='fd' filepath='drivers/usb/gadget/functions.c' line='111' column='1'/>
<return type-id='48b5725f'/>
</function-decl>
- <function-decl name='usb_gadget_activate' mangled-name='usb_gadget_activate' filepath='drivers/usb/gadget/udc/core.c' line='792' column='1' visibility='default' binding='global' size-in-bits='64' elf-symbol-id='usb_gadget_activate'>
- <parameter type-id='49a58c0c' name='gadget' filepath='drivers/usb/gadget/udc/core.c' line='792' column='1'/>
+ <function-decl name='usb_gadget_activate' mangled-name='usb_gadget_activate' filepath='drivers/usb/gadget/udc/core.c' line='793' column='1' visibility='default' binding='global' size-in-bits='64' elf-symbol-id='usb_gadget_activate'>
+ <parameter type-id='49a58c0c' name='gadget' filepath='drivers/usb/gadget/udc/core.c' line='793' column='1'/>
<return type-id='95e97e5e'/>
</function-decl>
- <function-decl name='usb_gadget_deactivate' mangled-name='usb_gadget_deactivate' filepath='drivers/usb/gadget/udc/core.c' line='756' column='1' visibility='default' binding='global' size-in-bits='64' elf-symbol-id='usb_gadget_deactivate'>
- <parameter type-id='49a58c0c' name='gadget' filepath='drivers/usb/gadget/udc/core.c' line='756' column='1'/>
+ <function-decl name='usb_gadget_deactivate' mangled-name='usb_gadget_deactivate' filepath='drivers/usb/gadget/udc/core.c' line='757' column='1' visibility='default' binding='global' size-in-bits='64' elf-symbol-id='usb_gadget_deactivate'>
+ <parameter type-id='49a58c0c' name='gadget' filepath='drivers/usb/gadget/udc/core.c' line='757' column='1'/>
<return type-id='95e97e5e'/>
</function-decl>
- <function-decl name='usb_gadget_giveback_request' mangled-name='usb_gadget_giveback_request' filepath='drivers/usb/gadget/udc/core.c' line='907' column='1' visibility='default' binding='global' size-in-bits='64' elf-symbol-id='usb_gadget_giveback_request'>
- <parameter type-id='63a08bf7' name='ep' filepath='drivers/usb/gadget/udc/core.c' line='907' column='1'/>
- <parameter type-id='1a494567' name='req' filepath='drivers/usb/gadget/udc/core.c' line='908' column='1'/>
+ <function-decl name='usb_gadget_giveback_request' mangled-name='usb_gadget_giveback_request' filepath='drivers/usb/gadget/udc/core.c' line='908' column='1' visibility='default' binding='global' size-in-bits='64' elf-symbol-id='usb_gadget_giveback_request'>
+ <parameter type-id='63a08bf7' name='ep' filepath='drivers/usb/gadget/udc/core.c' line='908' column='1'/>
+ <parameter type-id='1a494567' name='req' filepath='drivers/usb/gadget/udc/core.c' line='909' column='1'/>
<return type-id='48b5725f'/>
</function-decl>
- <function-decl name='usb_gadget_map_request' mangled-name='usb_gadget_map_request' filepath='drivers/usb/gadget/udc/core.c' line='860' column='1' visibility='default' binding='global' size-in-bits='64' elf-symbol-id='usb_gadget_map_request'>
- <parameter type-id='49a58c0c' name='gadget' filepath='drivers/usb/gadget/udc/core.c' line='860' column='1'/>
- <parameter type-id='1a494567' name='req' filepath='drivers/usb/gadget/udc/core.c' line='861' column='1'/>
- <parameter type-id='95e97e5e' name='is_in' filepath='drivers/usb/gadget/udc/core.c' line='861' column='1'/>
+ <function-decl name='usb_gadget_map_request' mangled-name='usb_gadget_map_request' filepath='drivers/usb/gadget/udc/core.c' line='861' column='1' visibility='default' binding='global' size-in-bits='64' elf-symbol-id='usb_gadget_map_request'>
+ <parameter type-id='49a58c0c' name='gadget' filepath='drivers/usb/gadget/udc/core.c' line='861' column='1'/>
+ <parameter type-id='1a494567' name='req' filepath='drivers/usb/gadget/udc/core.c' line='862' column='1'/>
+ <parameter type-id='95e97e5e' name='is_in' filepath='drivers/usb/gadget/udc/core.c' line='862' column='1'/>
<return type-id='95e97e5e'/>
</function-decl>
- <function-decl name='usb_gadget_probe_driver' mangled-name='usb_gadget_probe_driver' filepath='drivers/usb/gadget/udc/core.c' line='1527' column='1' visibility='default' binding='global' size-in-bits='64' elf-symbol-id='usb_gadget_probe_driver'>
- <parameter type-id='9762ede1' name='driver' filepath='drivers/usb/gadget/udc/core.c' line='1527' column='1'/>
+ <function-decl name='usb_gadget_probe_driver' mangled-name='usb_gadget_probe_driver' filepath='drivers/usb/gadget/udc/core.c' line='1528' column='1' visibility='default' binding='global' size-in-bits='64' elf-symbol-id='usb_gadget_probe_driver'>
+ <parameter type-id='9762ede1' name='driver' filepath='drivers/usb/gadget/udc/core.c' line='1528' column='1'/>
<return type-id='95e97e5e'/>
</function-decl>
- <function-decl name='usb_gadget_set_state' mangled-name='usb_gadget_set_state' filepath='drivers/usb/gadget/udc/core.c' line='1039' column='1' visibility='default' binding='global' size-in-bits='64' elf-symbol-id='usb_gadget_set_state'>
- <parameter type-id='49a58c0c' name='gadget' filepath='drivers/usb/gadget/udc/core.c' line='1039' column='1'/>
- <parameter type-id='901a91cb' name='state' filepath='drivers/usb/gadget/udc/core.c' line='1040' column='1'/>
+ <function-decl name='usb_gadget_set_state' mangled-name='usb_gadget_set_state' filepath='drivers/usb/gadget/udc/core.c' line='1040' column='1' visibility='default' binding='global' size-in-bits='64' elf-symbol-id='usb_gadget_set_state'>
+ <parameter type-id='49a58c0c' name='gadget' filepath='drivers/usb/gadget/udc/core.c' line='1040' column='1'/>
+ <parameter type-id='901a91cb' name='state' filepath='drivers/usb/gadget/udc/core.c' line='1041' column='1'/>
<return type-id='48b5725f'/>
</function-decl>
- <function-decl name='usb_gadget_unmap_request' mangled-name='usb_gadget_unmap_request' filepath='drivers/usb/gadget/udc/core.c' line='886' column='1' visibility='default' binding='global' size-in-bits='64' elf-symbol-id='usb_gadget_unmap_request'>
- <parameter type-id='49a58c0c' name='gadget' filepath='drivers/usb/gadget/udc/core.c' line='886' column='1'/>
- <parameter type-id='1a494567' name='req' filepath='drivers/usb/gadget/udc/core.c' line='887' column='1'/>
- <parameter type-id='95e97e5e' name='is_in' filepath='drivers/usb/gadget/udc/core.c' line='887' column='1'/>
+ <function-decl name='usb_gadget_unmap_request' mangled-name='usb_gadget_unmap_request' filepath='drivers/usb/gadget/udc/core.c' line='887' column='1' visibility='default' binding='global' size-in-bits='64' elf-symbol-id='usb_gadget_unmap_request'>
+ <parameter type-id='49a58c0c' name='gadget' filepath='drivers/usb/gadget/udc/core.c' line='887' column='1'/>
+ <parameter type-id='1a494567' name='req' filepath='drivers/usb/gadget/udc/core.c' line='888' column='1'/>
+ <parameter type-id='95e97e5e' name='is_in' filepath='drivers/usb/gadget/udc/core.c' line='888' column='1'/>
<return type-id='48b5725f'/>
</function-decl>
- <function-decl name='usb_gadget_unregister_driver' mangled-name='usb_gadget_unregister_driver' filepath='drivers/usb/gadget/udc/core.c' line='1574' column='1' visibility='default' binding='global' size-in-bits='64' elf-symbol-id='usb_gadget_unregister_driver'>
- <parameter type-id='9762ede1' name='driver' filepath='drivers/usb/gadget/udc/core.c' line='1574' column='1'/>
+ <function-decl name='usb_gadget_unregister_driver' mangled-name='usb_gadget_unregister_driver' filepath='drivers/usb/gadget/udc/core.c' line='1575' column='1' visibility='default' binding='global' size-in-bits='64' elf-symbol-id='usb_gadget_unregister_driver'>
+ <parameter type-id='9762ede1' name='driver' filepath='drivers/usb/gadget/udc/core.c' line='1575' column='1'/>
<return type-id='95e97e5e'/>
</function-decl>
<function-decl name='usb_gadget_vbus_draw' mangled-name='usb_gadget_vbus_draw' filepath='drivers/usb/gadget/udc/core.c' line='609' column='1' visibility='default' binding='global' size-in-bits='64' elf-symbol-id='usb_gadget_vbus_draw'>
@@ -139596,7 +139602,7 @@
<parameter type-id='bd300bf3' name='anchor' filepath='drivers/usb/core/urb.c' line='982' column='1'/>
<return type-id='ab85b8f2'/>
</function-decl>
- <function-decl name='usb_get_gadget_udc_name' mangled-name='usb_get_gadget_udc_name' filepath='drivers/usb/gadget/udc/core.c' line='1393' column='1' visibility='default' binding='global' size-in-bits='64' elf-symbol-id='usb_get_gadget_udc_name'>
+ <function-decl name='usb_get_gadget_udc_name' mangled-name='usb_get_gadget_udc_name' filepath='drivers/usb/gadget/udc/core.c' line='1394' column='1' visibility='default' binding='global' size-in-bits='64' elf-symbol-id='usb_get_gadget_udc_name'>
<return type-id='26a90f95'/>
</function-decl>
<function-decl name='usb_get_intf' mangled-name='usb_get_intf' filepath='drivers/usb/core/usb.c' line='728' column='1' visibility='default' binding='global' size-in-bits='64' elf-symbol-id='usb_get_intf'>
@@ -139855,9 +139861,9 @@
<parameter type-id='3eb7c31c' name='mem_flags' filepath='drivers/usb/core/urb.c' line='367' column='1'/>
<return type-id='95e97e5e'/>
</function-decl>
- <function-decl name='usb_udc_vbus_handler' mangled-name='usb_udc_vbus_handler' filepath='drivers/usb/gadget/udc/core.c' line='1066' column='1' visibility='default' binding='global' size-in-bits='64' elf-symbol-id='usb_udc_vbus_handler'>
- <parameter type-id='49a58c0c' name='gadget' filepath='drivers/usb/gadget/udc/core.c' line='1066' column='1'/>
- <parameter type-id='b50a4934' name='status' filepath='drivers/usb/gadget/udc/core.c' line='1066' column='1'/>
+ <function-decl name='usb_udc_vbus_handler' mangled-name='usb_udc_vbus_handler' filepath='drivers/usb/gadget/udc/core.c' line='1067' column='1' visibility='default' binding='global' size-in-bits='64' elf-symbol-id='usb_udc_vbus_handler'>
+ <parameter type-id='49a58c0c' name='gadget' filepath='drivers/usb/gadget/udc/core.c' line='1067' column='1'/>
+ <parameter type-id='b50a4934' name='status' filepath='drivers/usb/gadget/udc/core.c' line='1067' column='1'/>
<return type-id='48b5725f'/>
</function-decl>
<function-decl name='usb_unanchor_urb' mangled-name='usb_unanchor_urb' filepath='drivers/usb/core/urb.c' line='164' column='1' visibility='default' binding='global' size-in-bits='64' elf-symbol-id='usb_unanchor_urb'>
@@ -141573,7 +141579,6 @@
</abi-instr>
</abi-corpus>
</abi-corpus-group>
-
<!--
libabigail: abidw: 2.1.0SOONG BUILD NUMBER PLACEHOLDER
-->
diff --git a/include/linux/rmap.h b/include/linux/rmap.h
index 26f49f1..82ee948 100644
--- a/include/linux/rmap.h
+++ b/include/linux/rmap.h
@@ -38,13 +38,7 @@
*/
atomic_t refcount;
- /*
- * Count of child anon_vmas and VMAs which points to this anon_vma.
- *
- * This counter is used for making decision about reusing anon_vma
- * instead of forking new one. See comments in function anon_vma_clone.
- */
- unsigned degree;
+ unsigned degree; /* ANDROID: KABI preservation, DO NOT USE! */
struct anon_vma *parent; /* Parent of this anon_vma */
@@ -59,6 +53,25 @@
/* Interval tree of private "related" vmas */
struct rb_root_cached rb_root;
+
+ /*
+ * ANDROID: KABI preservation, it's safe to put these at the end of this structure as it's
+ * only passed by a pointer everywhere, the size and internal structures are local to the
+ * core kernel.
+ */
+#ifndef __GENKSYMS__
+ /*
+ * Count of child anon_vmas. Equals to the count of all anon_vmas that
+ * have ->parent pointing to this one, including itself.
+ *
+ * This counter is used for making decision about reusing anon_vma
+ * instead of forking new one. See comments in function anon_vma_clone.
+ */
+ unsigned long num_children;
+ /* Count of VMAs whose ->anon_vma pointer points to this object. */
+ unsigned long num_active_vmas;
+#endif
+
};
/*
diff --git a/mm/rmap.c b/mm/rmap.c
index 663c040..48073b9 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -90,7 +90,8 @@
anon_vma = kmem_cache_alloc(anon_vma_cachep, GFP_KERNEL);
if (anon_vma) {
atomic_set(&anon_vma->refcount, 1);
- anon_vma->degree = 1; /* Reference for first vma */
+ anon_vma->num_children = 0;
+ anon_vma->num_active_vmas = 0;
anon_vma->parent = anon_vma;
/*
* Initialise the anon_vma root to point to itself. If called
@@ -198,6 +199,7 @@
anon_vma = anon_vma_alloc();
if (unlikely(!anon_vma))
goto out_enomem_free_avc;
+ anon_vma->num_children++; /* self-parent link for new root */
allocated = anon_vma;
}
@@ -207,8 +209,7 @@
if (likely(!vma->anon_vma)) {
vma->anon_vma = anon_vma;
anon_vma_chain_link(vma, avc, anon_vma);
- /* vma reference or self-parent link for new root */
- anon_vma->degree++;
+ anon_vma->num_active_vmas++;
allocated = NULL;
avc = NULL;
}
@@ -293,19 +294,19 @@
anon_vma_chain_link(dst, avc, anon_vma);
/*
- * Reuse existing anon_vma if its degree lower than two,
- * that means it has no vma and only one anon_vma child.
+ * Reuse existing anon_vma if it has no vma and only one
+ * anon_vma child.
*
- * Do not chose parent anon_vma, otherwise first child
- * will always reuse it. Root anon_vma is never reused:
+ * Root anon_vma is never reused:
* it has self-parent reference and at least one child.
*/
if (!dst->anon_vma && src->anon_vma &&
- anon_vma != src->anon_vma && anon_vma->degree < 2)
+ anon_vma->num_children < 2 &&
+ anon_vma->num_active_vmas == 0)
dst->anon_vma = anon_vma;
}
if (dst->anon_vma)
- dst->anon_vma->degree++;
+ dst->anon_vma->num_active_vmas++;
unlock_anon_vma_root(root);
return 0;
@@ -355,6 +356,7 @@
anon_vma = anon_vma_alloc();
if (!anon_vma)
goto out_error;
+ anon_vma->num_active_vmas++;
avc = anon_vma_chain_alloc(GFP_KERNEL);
if (!avc)
goto out_error_free_anon_vma;
@@ -375,7 +377,7 @@
vma->anon_vma = anon_vma;
anon_vma_lock_write(anon_vma);
anon_vma_chain_link(vma, avc, anon_vma);
- anon_vma->parent->degree++;
+ anon_vma->parent->num_children++;
anon_vma_unlock_write(anon_vma);
return 0;
@@ -407,7 +409,7 @@
* to free them outside the lock.
*/
if (RB_EMPTY_ROOT(&anon_vma->rb_root.rb_root)) {
- anon_vma->parent->degree--;
+ anon_vma->parent->num_children--;
continue;
}
@@ -415,7 +417,8 @@
anon_vma_chain_free(avc);
}
if (vma->anon_vma)
- vma->anon_vma->degree--;
+ vma->anon_vma->num_active_vmas--;
+
unlock_anon_vma_root(root);
/*
@@ -426,7 +429,8 @@
list_for_each_entry_safe(avc, next, &vma->anon_vma_chain, same_vma) {
struct anon_vma *anon_vma = avc->anon_vma;
- VM_WARN_ON(anon_vma->degree);
+ VM_WARN_ON(anon_vma->num_children);
+ VM_WARN_ON(anon_vma->num_active_vmas);
put_anon_vma(anon_vma);
list_del(&avc->same_vma);
