From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.suse.de (mx2.suse.de [195.135.220.15]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ml01.01.org (Postfix) with ESMTPS id E36A221244A5F for ; Fri, 3 May 2019 03:48:38 -0700 (PDT) Date: Fri, 3 May 2019 12:48:32 +0200 From: Oscar Salvador Subject: Re: [PATCH v6 00/12] mm: Sub-section memory hotplug support Message-ID: <20190503104831.GF15740@linux> References: <155552633539.2015392.2477781120122237934.stgit@dwillia2-desk3.amr.corp.intel.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: linux-nvdimm-bounces@lists.01.org Sender: "Linux-nvdimm" To: Dan Williams Cc: Michal Hocko , Pavel Tatashin , David Hildenbrand , linux-nvdimm , stable , LKML , linux-mm , =?iso-8859-1?B?Suly9G1l?= Glisse , Andrew Morton , Vlastimil Babka List-ID: On Thu, May 02, 2019 at 04:20:03PM -0700, Dan Williams wrote: > On Thu, May 2, 2019 at 3:46 PM Pavel Tatashin wrote: > > > > Hi Dan, > > > > How do you test these patches? Do you have any instructions? > > Yes, I briefly mentioned this in the cover letter, but here is the > test I am using: > > > > > I see for example that check_hotplug_memory_range() still enforces > > memory_block_size_bytes() alignment. > > > > Also, after removing check_hotplug_memory_range(), I tried to online > > 16M aligned DAX memory, and got the following panic: > > Right, this functionality is currently strictly limited to the > devm_memremap_pages() case where there are guarantees that the memory > will never be onlined. This is due to the fact that the section size > is entangled with the memblock api. That said I would have expected > you to trigger the warning in subsection_check() before getting this > far into the hotplug process. > > > > # echo online > /sys/devices/system/memory/memory7/state > > [ 202.193132] WARNING: CPU: 2 PID: 351 at drivers/base/memory.c:207 > > memory_block_action+0x110/0x178 > > [ 202.193391] Modules linked in: > > [ 202.193698] CPU: 2 PID: 351 Comm: sh Not tainted > > 5.1.0-rc7_pt_devdax-00038-g865af4385544-dirty #9 > > [ 202.193909] Hardware name: linux,dummy-virt (DT) > > [ 202.194122] pstate: 60000005 (nZCv daif -PAN -UAO) > > [ 202.194243] pc : memory_block_action+0x110/0x178 > > [ 202.194404] lr : memory_block_action+0x90/0x178 > > [ 202.194506] sp : ffff000016763ca0 > > [ 202.194592] x29: ffff000016763ca0 x28: ffff80016fd29b80 > > [ 202.194724] x27: 0000000000000000 x26: 0000000000000000 > > [ 202.194838] x25: ffff000015546000 x24: 00000000001c0000 > > [ 202.194949] x23: 0000000000000000 x22: 0000000000040000 > > [ 202.195058] x21: 00000000001c0000 x20: 0000000000000008 > > [ 202.195168] x19: 0000000000000007 x18: 0000000000000000 > > [ 202.195281] x17: 0000000000000000 x16: 0000000000000000 > > [ 202.195393] x15: 0000000000000000 x14: 0000000000000000 > > [ 202.195505] x13: 0000000000000000 x12: 0000000000000000 > > [ 202.195614] x11: 0000000000000000 x10: 0000000000000000 > > [ 202.195744] x9 : 0000000000000000 x8 : 0000000180000000 > > [ 202.195858] x7 : 0000000000000018 x6 : ffff000015541930 > > [ 202.195966] x5 : ffff000015541930 x4 : 0000000000000001 > > [ 202.196074] x3 : 0000000000000001 x2 : 0000000000000000 > > [ 202.196185] x1 : 0000000000000070 x0 : 0000000000000000 > > [ 202.196366] Call trace: > > [ 202.196455] memory_block_action+0x110/0x178 > > [ 202.196589] memory_subsys_online+0x3c/0x80 > > [ 202.196681] device_online+0x6c/0x90 > > [ 202.196761] state_store+0x84/0x100 > > [ 202.196841] dev_attr_store+0x18/0x28 > > [ 202.196927] sysfs_kf_write+0x40/0x58 > > [ 202.197010] kernfs_fop_write+0xcc/0x1d8 > > [ 202.197099] __vfs_write+0x18/0x40 > > [ 202.197187] vfs_write+0xa4/0x1b0 > > [ 202.197295] ksys_write+0x64/0xd8 > > [ 202.197430] __arm64_sys_write+0x18/0x20 > > [ 202.197521] el0_svc_common.constprop.0+0x7c/0xe8 > > [ 202.197621] el0_svc_handler+0x28/0x78 > > [ 202.197706] el0_svc+0x8/0xc > > [ 202.197828] ---[ end trace 57719823dda6d21e ]--- This warning relates to: for (; section_nr < section_nr_end; section_nr++) { if (WARN_ON_ONCE(!pfn_valid(pfn))) return false; from pages_correctly_probed(). AFAICS, this is orthogonal to subsection_check(). -- Oscar Salvador SUSE L3 _______________________________________________ Linux-nvdimm mailing list Linux-nvdimm@lists.01.org https://lists.01.org/mailman/listinfo/linux-nvdimm