> -----Original Message----- > From: liwei (CM) > Sent: Wednesday, July 8, 2020 7:52 PM > To: Song Bao Hua (Barry Song) <song.bao....@hisilicon.com>; > catalin.mari...@arm.com; w...@kernel.org > Cc: fengbaopeng <fengbaope...@hisilicon.com>; nsaenzjulie...@suse.de; > steve.cap...@arm.com; r...@linux.ibm.com; > linux-arm-ker...@lists.infradead.org; linux-kernel@vger.kernel.org; sujunfei > <sujunf...@hisilicon.com>; Xiaqing (A) <saberlily....@hisilicon.com>; > Yaobaofeng (Yaobaofeng) <yaobaof...@huawei.com> > Subject: 答复: [PATCH] arm64: mm: free unused memmap for sparse memory > model that define VMEMMAP > > Hi, baohua > > Thank you for your attention. > > In my understanding of the MEMORY_HOTPLUG this patch has no effect on it. > The reason is that in sparse_add_one_section() the memory that memmap > needs from Slab if kernel start completed，this memory has nothing to do with > memblock alloc/ free memory in the process of kernel start. > > You may have a look vmemmap_alloc_block () this function. > > If I don't understand right welcome pointed out in a timely manner.
At the first glance of this patch, I suspect that this bootmem may be used by hot-added memory. If you confirm this won't happen, please ignore my noise. BTW, next time, bear in mind that top-post is not a good way to reply mail :-) > > Thanks! > > > -----邮件原件----- > 发件人: Song Bao Hua (Barry Song) > 发送时间: 2020年7月8日 15:19 > 收件人: liwei (CM) <liwei...@huawei.com>; catalin.mari...@arm.com; > w...@kernel.org > 抄送: fengbaopeng <fengbaope...@hisilicon.com>; nsaenzjulie...@suse.de; > steve.cap...@arm.com; r...@linux.ibm.com; > linux-arm-ker...@lists.infradead.org; linux-kernel@vger.kernel.org; sujunfei > <sujunf...@hisilicon.com> > 主题: RE: [PATCH] arm64: mm: free unused memmap for sparse memory > model that define VMEMMAP > > > > > -----Original Message----- > > From: liwei (CM) > > Sent: Wednesday, July 8, 2020 1:56 PM > > To: catalin.mari...@arm.com; w...@kernel.org > > Cc: liwei (CM) <liwei...@huawei.com>; fengbaopeng > > <fengbaope...@hisilicon.com>; nsaenzjulie...@suse.de; > > steve.cap...@arm.com; r...@linux.ibm.com; Song Bao Hua (Barry Song) > > <song.bao....@hisilicon.com>; linux-arm-ker...@lists.infradead.org; > > linux-kernel@vger.kernel.org; sujunfei <sujunf...@hisilicon.com> > > Subject: [PATCH] arm64: mm: free unused memmap for sparse memory > model > > that define VMEMMAP > > > > For the memory hole, sparse memory model that define > SPARSEMEM_VMEMMAP > > do not free the reserved memory for the page map, this patch do it. > > Hello Wei, > Just curious if this patch breaks MEMORY_HOTPLUG? > > > > > Signed-off-by: Wei Li <liwei...@huawei.com> > > Signed-off-by: Chen Feng <puck.c...@hisilicon.com> > > Signed-off-by: Xia Qing <saberlily....@hisilicon.com> > > --- > > arch/arm64/mm/init.c | 81 > > +++++++++++++++++++++++++++++++++++++++++++++------- > > 1 file changed, 71 insertions(+), 10 deletions(-) > > > > diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c index > > 1e93cfc7c47a..d1b56b47d5ba 100644 > > --- a/arch/arm64/mm/init.c > > +++ b/arch/arm64/mm/init.c > > @@ -441,7 +441,48 @@ void __init bootmem_init(void) > > memblock_dump_all(); > > } > > > > Thanks > Barry
