[Crash-utility] [PATCH] Fix for "kmem -s|-S" and "bt -F[F]" on Linux 5.17-rc1
Since the following kernel commits split slab info from struct page
into struct slab, crash cannot get several slab related offsets from
struct page.
d122019bf061 ("mm: Split slab into its own type")
07f910f9b729 ("mm: Remove slab from struct page")
Without the patch, "kmem -s|-S" and "bt -F[F]" options cannot work
correctly with the following errors:
crash> kmem -s kmem_cache
CACHE OBJSIZE ALLOCATED TOTAL SLABS SSIZE NAME
kmem: page_to_nid: invalid page: ffff9454afc35020
kmem: kmem_cache: cannot gather relevant slab data
ffff945140042000 216 ? ? ? 8k kmem_cache
crash> bt -F
...
bt: invalid structure member offset: page_slab
FILE: memory.c LINE: 9477 FUNCTION: vaddr_to_kmem_cache()
Signed-by: Kazuhito Hagio <k-hagio-ab(a)nec.com>
---
memory.c | 13 +++++++++++++
1 file changed, 13 insertions(+)
diff --git a/memory.c b/memory.c
index e80c59ea4534..8448ddc3a16c 100644
--- a/memory.c
+++ b/memory.c
@@ -421,6 +421,8 @@ vm_init(void)
MEMBER_OFFSET_INIT(page_prev, "page", "prev");
if (INVALID_MEMBER(page_next))
ANON_MEMBER_OFFSET_INIT(page_next, "page", "next");
+ if (INVALID_MEMBER(page_next))
+ MEMBER_OFFSET_INIT(page_next, "slab", "next");
MEMBER_OFFSET_INIT(page_list, "page", "list");
if (VALID_MEMBER(page_list)) {
@@ -747,11 +749,15 @@ vm_init(void)
MEMBER_OFFSET_INIT(kmem_cache_random, "kmem_cache", "random");
MEMBER_OFFSET_INIT(kmem_cache_cpu_freelist, "kmem_cache_cpu",
"freelist");
MEMBER_OFFSET_INIT(kmem_cache_cpu_page, "kmem_cache_cpu", "page");
+ if (INVALID_MEMBER(kmem_cache_cpu_page))
+ MEMBER_OFFSET_INIT(kmem_cache_cpu_page, "kmem_cache_cpu",
"slab");
MEMBER_OFFSET_INIT(kmem_cache_cpu_node, "kmem_cache_cpu", "node");
MEMBER_OFFSET_INIT(kmem_cache_cpu_partial, "kmem_cache_cpu",
"partial");
MEMBER_OFFSET_INIT(page_inuse, "page", "inuse");
if (INVALID_MEMBER(page_inuse))
ANON_MEMBER_OFFSET_INIT(page_inuse, "page", "inuse");
+ if (INVALID_MEMBER(page_inuse))
+ MEMBER_OFFSET_INIT(page_inuse, "slab", "inuse");
MEMBER_OFFSET_INIT(page_offset, "page", "offset");
if (INVALID_MEMBER(page_offset))
ANON_MEMBER_OFFSET_INIT(page_offset, "page", "offset");
@@ -763,6 +769,9 @@ vm_init(void)
if (INVALID_MEMBER(page_slab))
ANON_MEMBER_OFFSET_INIT(page_slab, "page", "slab_cache");
}
+ if (INVALID_MEMBER(page_slab))
+ MEMBER_OFFSET_INIT(page_slab, "slab", "slab_cache");
+
MEMBER_OFFSET_INIT(page_slab_page, "page", "slab_page");
if (INVALID_MEMBER(page_slab_page))
ANON_MEMBER_OFFSET_INIT(page_slab_page, "page", "slab_page");
@@ -772,10 +781,14 @@ vm_init(void)
MEMBER_OFFSET_INIT(page_freelist, "page", "freelist");
if (INVALID_MEMBER(page_freelist))
ANON_MEMBER_OFFSET_INIT(page_freelist, "page", "freelist");
+ if (INVALID_MEMBER(page_freelist))
+ MEMBER_OFFSET_INIT(page_freelist, "slab", "freelist");
if (INVALID_MEMBER(kmem_cache_objects)) {
MEMBER_OFFSET_INIT(kmem_cache_oo, "kmem_cache", "oo");
/* NOTE: returns offset of containing bitfield */
ANON_MEMBER_OFFSET_INIT(page_objects, "page", "objects");
+ if (INVALID_MEMBER(page_objects))
+ ANON_MEMBER_OFFSET_INIT(page_objects, "slab", "objects");
}
if (VALID_MEMBER(kmem_cache_node)) {
ARRAY_LENGTH_INIT(len, NULL, "kmem_cache.node", NULL, 0);
--
2.27.0