From dc18d706a4367454ad1fc51e06148d54e8ecfaa0 Mon Sep 17 00:00:00 2001 From: Nathan Fontenot Date: Fri, 24 Feb 2017 15:00:02 -0800 Subject: memory-hotplug: use dev_online for memhp_auto_online Commit 31bc3858ea3e ("add automatic onlining policy for the newly added memory") provides the capability to have added memory automatically onlined during add, but this appears to be slightly broken. The current implementation uses walk_memory_range() to call online_memory_block, which uses memory_block_change_state() to online the memory. Instead, we should be calling device_online() for the memory block in online_memory_block(). This would online the memory (the memory bus online routine memory_subsys_online() called from device_online calls memory_block_change_state()) and properly update the device struct offline flag. As a result of the current implementation, attempting to remove a memory block after adding it using auto online fails. This is because doing a remove, for instance echo offline > /sys/devices/system/memory/memoryXXX/state uses device_offline() which checks the dev->offline flag. Link: http://lkml.kernel.org/r/20170222220744.8119.19687.stgit@ltcalpine2-lp14.aus.stglabs.ibm.com Signed-off-by: Nathan Fontenot Cc: Michael Ellerman Cc: Michael Roth Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/memory_hotplug.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'mm') diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index c35dd1976574..1d3ed58f92ab 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -1337,7 +1337,7 @@ int zone_for_memory(int nid, u64 start, u64 size, int zone_default, static int online_memory_block(struct memory_block *mem, void *arg) { - return memory_block_change_state(mem, MEM_ONLINE, MEM_OFFLINE); + return device_online(&mem->dev); } /* we are OK calling __meminit stuff here - we have CONFIG_MEMORY_HOTPLUG */ -- cgit v1.2.3