The patch titled
Subject: mm: make mem_dump_obj() handle vmalloc() memory
has been added to the -mm tree. Its filename is
mm-make-mem_dump_obj-handle-vmalloc-memory.patch
This patch should soon appear at
https://ozlabs.org/~akpm/mmots/broken-out/mm-make-mem_dump_obj-handle-vmalloc-memory.patch
and later at
https://ozlabs.org/~akpm/mmotm/broken-out/mm-make-mem_dump_obj-handle-vmalloc-memory.patch
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------------------------------------------------------
From: "Paul E. McKenney" <paulmck@xxxxxxxxxx>
Subject: mm: make mem_dump_obj() handle vmalloc() memory
This commit adds vmalloc() support to mem_dump_obj(). Note that the
vmalloc_dump_obj() function combines the checking and dumping, in contrast
with the split between kmem_valid_obj() and kmem_dump_obj(). The reason
for the difference is that the checking in the vmalloc() case involves
acquiring a global lock, and redundant acquisitions of global locks should
be avoided, even on not-so-fast paths.
Note that this change causes on-stack variables to be reported as
vmalloc() storage from kernel_clone() or similar, depending on the degree
of inlining that your compiler does. This is likely more helpful than the
earlier "non-paged (local) memory".
Link: https://lkml.kernel.org/r/20210106011750.13709-3-paulmck@xxxxxxxxxx
Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxx>
Reported-by: Andrii Nakryiko <andrii@xxxxxxxxxx>
Cc: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx>
Cc: Christoph Lameter <cl@xxxxxxxxx>
Cc: David Rientjes <rientjes@xxxxxxxxxx>
Cc: Jens Axboe <axboe@xxxxxxxxx>
Cc: Ming Lei <ming.lei@xxxxxxxxxx>
Cc: Pekka Enberg <penberg@xxxxxxxxxx>
Cc: Vlastimil Babka <vbabka@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/vmalloc.h | 6 ++++++
mm/util.c | 14 ++++++++------
mm/vmalloc.c | 12 ++++++++++++
3 files changed, 26 insertions(+), 6 deletions(-)
--- a/include/linux/vmalloc.h~mm-make-mem_dump_obj-handle-vmalloc-memory
+++ a/include/linux/vmalloc.h
@@ -246,4 +246,10 @@ pcpu_free_vm_areas(struct vm_struct **vm
int register_vmap_purge_notifier(struct notifier_block *nb);
int unregister_vmap_purge_notifier(struct notifier_block *nb);
+#ifdef CONFIG_MMU
+bool vmalloc_dump_obj(void *object);
+#else
+static inline bool vmalloc_dump_obj(void *object) { return false; }
+#endif
+
#endif /* _LINUX_VMALLOC_H */
--- a/mm/util.c~mm-make-mem_dump_obj-handle-vmalloc-memory
+++ a/mm/util.c
@@ -996,18 +996,20 @@ int __weak memcmp_pages(struct page *pag
*/
void mem_dump_obj(void *object)
{
+ if (kmem_valid_obj(object)) {
+ kmem_dump_obj(object);
+ return;
+ }
+ if (vmalloc_dump_obj(object))
+ return;
if (!virt_addr_valid(object)) {
if (object == NULL)
pr_cont(" NULL pointer.\n");
else if (object == ZERO_SIZE_PTR)
pr_cont(" zero-size pointer.\n");
else
- pr_cont(" non-paged (local) memory.\n");
- return;
- }
- if (kmem_valid_obj(object)) {
- kmem_dump_obj(object);
+ pr_cont(" non-paged memory.\n");
return;
}
- pr_cont(" non-slab memory.\n");
+ pr_cont(" non-slab/vmalloc memory.\n");
}
--- a/mm/vmalloc.c~mm-make-mem_dump_obj-handle-vmalloc-memory
+++ a/mm/vmalloc.c
@@ -3448,6 +3448,18 @@ void pcpu_free_vm_areas(struct vm_struct
}
#endif /* CONFIG_SMP */
+bool vmalloc_dump_obj(void *object)
+{
+ struct vm_struct *vm;
+ void *objp = (void *)PAGE_ALIGN((unsigned long)object);
+
+ vm = find_vm_area(objp);
+ if (!vm)
+ return false;
+ pr_cont(" vmalloc allocated at %pS\n", vm->caller);
+ return true;
+}
+
#ifdef CONFIG_PROC_FS
static void *s_start(struct seq_file *m, loff_t *pos)
__acquires(&vmap_purge_lock)
_
Patches currently in -mm which might be from paulmck@xxxxxxxxxx are
mm-add-mem_dump_obj-to-print-source-of-memory-block.patch
mm-make-mem_dump_obj-handle-null-and-zero-sized-pointers.patch
mm-make-mem_dump_obj-handle-vmalloc-memory.patch
mm-make-mem_obj_dump-vmalloc-dumps-include-start-and-length.patch
rcu-make-call_rcu-print-mem_dump_obj-info-for-double-freed-callback.patch
percpu_ref-dump-mem_dump_obj-info-upon-reference-count-underflow.patch
