The patch titled Subject: mm/slub: use stackdepot to save stack trace in objects-fix has been removed from the -mm tree. Its filename was mm-slub-use-stackdepot-to-save-stack-trace-in-objects-fix-2.patch This patch was dropped because it was folded into mm-slub-use-stackdepot-to-save-stack-trace-in-objects.patch ------------------------------------------------------ From: Vlastimil Babka <vbabka@xxxxxxx> Subject: mm/slub: use stackdepot to save stack trace in objects-fix Paul reports [1] lockdep splat HARDIRQ-safe -> HARDIRQ-unsafe lock order detected. Kernel test robot reports [2] BUG:sleeping_function_called_from_invalid_context_at_mm/page_alloc.c The stack trace might be saved from contexts where we can't block so GFP_KERNEL is unsafe. So use GFP_NOWAIT. Under memory pressure we might thus fail to save some new unique stack, but that should be extremely rare. [1] https://lore.kernel.org/linux-mm/20210515204622.GA2672367@paulmck-ThinkPad-P17-Gen-1/ [2] https://lore.kernel.org/linux-mm/20210516144152.GA25903@xsang-OptiPlex-9020/ Link: https://lkml.kernel.org/r/20210516195150.26740-1-vbabka@xxxxxxx Signed-off-by: Vlastimil Babka <vbabka@xxxxxxx> Reported-by: Paul E. McKenney <paulmck@xxxxxxxxxx> Tested-by: Paul E. McKenney <paulmck@xxxxxxxxxx> Reported-by: kernel test robot <oliver.sang@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/slub.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/mm/slub.c~mm-slub-use-stackdepot-to-save-stack-trace-in-objects-fix-2 +++ a/mm/slub.c @@ -646,7 +646,7 @@ static void set_track(struct kmem_cache if (addr) { #ifdef CONFIG_STACKDEPOT - p->handle = save_stack_depot_trace(GFP_KERNEL); + p->handle = save_stack_depot_trace(GFP_NOWAIT); #endif p->addr = addr; p->cpu = smp_processor_id(); _ Patches currently in -mm which might be from vbabka@xxxxxxx are mm-slub-use-stackdepot-to-save-stack-trace-in-objects.patch