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| author | Vlastimil Babka <vbabka@suse.cz> | 2021-10-28 14:23:39 +1100 |
|---|---|---|
| committer | Stephen Rothwell <sfr@canb.auug.org.au> | 2021-11-08 13:26:13 +1100 |
| commit | e4bc270a01d2ac65d97df31e35333ba88f68c69c (patch) | |
| tree | dc920f8e0c7b298446beb17f5e4fa15c42b59b76 | |
| parent | 2e1fae6d74c641191805c3ad2848ad69cc656470 (diff) | |
| download | linux-e4bc270a01d2ac65d97df31e35333ba88f68c69c.tar.gz linux-e4bc270a01d2ac65d97df31e35333ba88f68c69c.tar.xz | |
lib/stackdepot: allow optional init and stack_table allocation by kvmalloc() - fixup
On FLATMEM, we call page_ext_init_flatmem_late() just before
kmem_cache_init() which means stack_depot_init() (called by page owner
init) will not recognize properly it should use kvmalloc() and not
memblock_alloc(). memblock_alloc() will also not issue a warning and
return a block memory that can be invalid and cause kernel page fault when
saving stacks, as reported by the kernel test robot [1].
Fix this by moving page_ext_init_flatmem_late() below kmem_cache_init() so
that slab_is_available() is true during stack_depot_init(). SPARSEMEM
doesn't have this issue, as it doesn't do page_ext_init_flatmem_late(),
but a different page_ext_init() even later in the boot process.
Thanks to Mike Rapoport for pointing out the FLATMEM init ordering issue.
While at it, also actually resolve a checkpatch warning in stack_depot_init()
from DRM CI, which was supposed to be in the original patch already.
[1] https://lore.kernel.org/all/20211014085450.GC18719@xsang-OptiPlex-9020/
Link: https://lkml.kernel.org/r/6abd9213-19a9-6d58-cedc-2414386d2d81@suse.cz
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reported-by: kernel test robot <oliver.sang@intel.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
| -rw-r--r-- | init/main.c | 7 | ||||
| -rw-r--r-- | lib/stackdepot.c | 2 |
2 files changed, 6 insertions, 3 deletions
diff --git a/init/main.c b/init/main.c index ff8f83c2da5a..cf6452628ca1 100644 --- a/init/main.c +++ b/init/main.c @@ -840,9 +840,12 @@ static void __init mm_init(void) stack_depot_early_init(); mem_init(); mem_init_print_info(); - /* page_owner must be initialized after buddy is ready */ - page_ext_init_flatmem_late(); kmem_cache_init(); + /* + * page_owner must be initialized after buddy is ready, and also after + * slab is ready so that stack_depot_init() works properly + */ + page_ext_init_flatmem_late(); kmemleak_init(); pgtable_init(); debug_objects_mem_init(); diff --git a/lib/stackdepot.c b/lib/stackdepot.c index 8b6c41585203..00ccb106f1a8 100644 --- a/lib/stackdepot.c +++ b/lib/stackdepot.c @@ -171,7 +171,7 @@ __ref int stack_depot_init(void) static DEFINE_MUTEX(stack_depot_init_mutex); mutex_lock(&stack_depot_init_mutex); - if (!stack_depot_disable && stack_table == NULL) { + if (!stack_depot_disable && !stack_table) { size_t size = (STACK_HASH_SIZE * sizeof(struct stack_record *)); int i; |