From: Zhenhua Huang
mainline inclusion
from mainline-v5.11-rc1
commit 7fb7ab6d618a4dc7ea3f3eafc92388a35b4f8894
category: bugfix
issue: #I4NRS5
CVE: NA
Signed-off-by: Yu Changchun
-------------------------------------------------
Page owner of pages used by page owner itself used is missing on arm32
targets. The reason is dummy_handle and failure_handle is not initialized
correctly. Buddy allocator is used to initialize these two handles.
However, buddy allocator is not ready when page owner calls it. This
change fixed that by initializing page owner after buddy initialization.
The working flow before and after this change are:
original logic:
1. allocated memory for page_ext(using memblock).
2. invoke the init callback of page_ext_ops like page_owner(using buddy
allocator).
3. initialize buddy.
after this change:
1. allocated memory for page_ext(using memblock).
2. initialize buddy.
3. invoke the init callback of page_ext_ops like page_owner(using buddy
allocator).
with the change, failure/dummy_handle can get its correct value and page
owner output for example has the one for page owner itself:
Page allocated via order 2, mask 0x6202c0(GFP_USER|__GFP_NOWARN),
pid 1006, ts 67278156558 ns
PFN 543776 type Unmovable Block 531 type Unmovable Flags 0x0()
init_page_owner+0x28/0x2f8
invoke_init_callbacks_flatmem+0x24/0x34
start_kernel+0x33c/0x5d8
Link: https://lkml.kernel.org/r/1603104925-5888-1-git-send-email-zhenhuah@codeauro...
Signed-off-by: Zhenhua Huang
Acked-by: Vlastimil Babka
Cc: Joonsoo Kim
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
(cherry picked from commit 7fb7ab6d618a4dc7ea3f3eafc92388a35b4f8894)
Signed-off-by: Kefeng Wang
Signed-off-by: Yuanzheng Song
Reviewed-by: Kefeng Wang
Signed-off-by: Zheng Zengkai
Signed-off-by: Yu Changchun
---
include/linux/page_ext.h | 8 ++++++++
init/main.c | 2 ++
mm/page_ext.c | 10 ++++++++--
3 files changed, 18 insertions(+), 2 deletions(-)
diff --git a/include/linux/page_ext.h b/include/linux/page_ext.h
index cfce186f0c4e..aff81ba31bd8 100644
--- a/include/linux/page_ext.h
+++ b/include/linux/page_ext.h
@@ -44,8 +44,12 @@ static inline void page_ext_init_flatmem(void)
{
}
extern void page_ext_init(void);
+static inline void page_ext_init_flatmem_late(void)
+{
+}
#else
extern void page_ext_init_flatmem(void);
+extern void page_ext_init_flatmem_late(void);
static inline void page_ext_init(void)
{
}
@@ -76,6 +80,10 @@ static inline void page_ext_init(void)
{
}
+static inline void page_ext_init_flatmem_late(void)
+{
+}
+
static inline void page_ext_init_flatmem(void)
{
}
diff --git a/init/main.c b/init/main.c
index dd26a42e80a8..63cdf49f7f82 100644
--- a/init/main.c
+++ b/init/main.c
@@ -828,6 +828,8 @@ static void __init mm_init(void)
init_debug_pagealloc();
report_meminit();
mem_init();
+ /* page_owner must be initialized after buddy is ready */
+ page_ext_init_flatmem_late();
kmem_cache_init();
kmemleak_init();
pgtable_init();
diff --git a/mm/page_ext.c b/mm/page_ext.c
index a3616f7a0e9e..16b161f28a31 100644
--- a/mm/page_ext.c
+++ b/mm/page_ext.c
@@ -99,12 +99,19 @@ static void __init invoke_init_callbacks(void)
}
}
+#ifndef CONFIG_SPARSEMEM
+void __init page_ext_init_flatmem_late(void)
+{
+ invoke_init_callbacks();
+}
+#endif
+
static inline struct page_ext *get_entry(void *base, unsigned long index)
{
return base + page_ext_size * index;
}
-#if !defined(CONFIG_SPARSEMEM)
+#ifndef CONFIG_SPARSEMEM
void __meminit pgdat_page_ext_init(struct pglist_data *pgdat)
@@ -177,7 +184,6 @@ void __init page_ext_init_flatmem(void)
goto fail;
}
pr_info("allocated %ld bytes of page_ext\n", total_usage);
- invoke_init_callbacks();
return;
fail:
--
2.25.1
