6.11-stable review patch. If anyone has any objections, please let me know. ------------------ From: Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx> commit cb6fcef8b4b6c655b6a25cc3a415cd9eb81b3da8 upstream. Since gfp & GFP_ATOMIC == GFP_ATOMIC is true for GFP_KERNEL | GFP_HIGH, it will use kmalloc if user specifies that combination. Here the reason why combining the __vmalloc_node() and kmalloc_node() is that the vmalloc does not support all GFP flag, especially GFP_ATOMIC. So we should check if gfp & (GFP_ATOMIC | GFP_KERNEL) != GFP_ATOMIC for vmalloc first. This ensures caller can sleep. And for the robustness, even if vmalloc fails, it should retry with kmalloc to allocate it. Link: https://lkml.kernel.org/r/173008598713.1262174.2959179484209897252.stgit@xxxxxxxxxxxxxxxxxxxxxxxxxxxxx Fixes: aff1871bfc81 ("objpool: fix choosing allocation for percpu slots") Signed-off-by: Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx> Reported-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Closes: https://lore.kernel.org/all/CAHk-=whO+vSH+XVRio8byJU8idAWES0SPGVZ7KAVdc4qrV0VUA@xxxxxxxxxxxxxx/ Cc: Leo Yan <leo.yan@xxxxxxx> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Cc: Matt Wu <wuqiang.matt@xxxxxxxxxxxxx> Cc: Mikel Rychliski <mikel@xxxxxxxxxx> Cc: Steven Rostedt (Google) <rostedt@xxxxxxxxxxx> Cc: Viktor Malik <vmalik@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- lib/objpool.c | 18 ++++++++++++------ 1 file changed, 12 insertions(+), 6 deletions(-) diff --git a/lib/objpool.c b/lib/objpool.c index fd108fe0d095..b998b720c732 100644 --- a/lib/objpool.c +++ b/lib/objpool.c @@ -74,15 +74,21 @@ objpool_init_percpu_slots(struct objpool_head *pool, int nr_objs, * warm caches and TLB hits. in default vmalloc is used to * reduce the pressure of kernel slab system. as we know, * mimimal size of vmalloc is one page since vmalloc would - * always align the requested size to page size + * always align the requested size to page size. + * but if vmalloc fails or it is not available (e.g. GFP_ATOMIC) + * allocate percpu slot with kmalloc. */ - if ((pool->gfp & GFP_ATOMIC) == GFP_ATOMIC) - slot = kmalloc_node(size, pool->gfp, cpu_to_node(i)); - else + slot = NULL; + + if ((pool->gfp & (GFP_ATOMIC | GFP_KERNEL)) != GFP_ATOMIC) slot = __vmalloc_node(size, sizeof(void *), pool->gfp, cpu_to_node(i), __builtin_return_address(0)); - if (!slot) - return -ENOMEM; + + if (!slot) { + slot = kmalloc_node(size, pool->gfp, cpu_to_node(i)); + if (!slot) + return -ENOMEM; + } memset(slot, 0, size); pool->cpu_slots[i] = slot; -- 2.47.0
