From: Michal Hocko <mhocko@kernel.org>
To: Jeff Moyer <jmoyer@redhat.com>
Cc: "Dan Williams" <dan.j.williams@intel.com>,
"Andrew Morton" <akpm@linux-foundation.org>,
"Jérôme Glisse" <jglisse@redhat.com>,
"Logan Gunthorpe" <logang@deltatee.com>,
"Toshi Kani" <toshi.kani@hpe.com>,
"Vlastimil Babka" <vbabka@suse.cz>,
stable <stable@vger.kernel.org>, "Linux MM" <linux-mm@kvack.org>,
linux-nvdimm <linux-nvdimm@lists.01.org>,
"Linux Kernel Mailing List" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v5 00/10] mm: Sub-section memory hotplug support
Date: Mon, 25 Mar 2019 15:50:23 +0100 [thread overview]
Message-ID: <20190325145023.GG9924@dhcp22.suse.cz> (raw)
In-Reply-To: <x494l7rdo5r.fsf@segfault.boston.devel.redhat.com>
On Mon 25-03-19 10:28:00, Jeff Moyer wrote:
> Michal Hocko <mhocko@kernel.org> writes:
>
> >> > and I would like to know that you are
> >> > not just shifting the problem to a smaller unit and a new/creative HW
> >> > will force us to go even more complicated.
> >>
> >> HW will not do this to us. It's software that has the problem.
> >> Namespace creation is unnecessarily constrained to 128MB alignment.
> >
> > And why is that a problem? A lack of documentation that this is a
> > requirement? Something will not work with a larger alignment? Someting
> > else?
>
> See this email for one user-visible problem:
> https://lore.kernel.org/lkml/x49imxbx22d.fsf@segfault.boston.devel.redhat.com/
: # ndctl create-namespace -m fsdax -s 128m
: Error: '--size=' must align to interleave-width: 6 and alignment: 2097152
: did you intend --size=132M?
:
: failed to create namespace: Invalid argument
So the size is in section size units. So what prevents the userspace to
use a proper alignment? I am sorry if this is a stupid question but I am
not really familiar with ndctl nor the pmem side of it.
--
Michal Hocko
SUSE Labs
next prev parent reply other threads:[~2019-03-25 14:50 UTC|newest]
Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-03-22 16:57 [PATCH v5 00/10] mm: Sub-section memory hotplug support Dan Williams
2019-03-22 16:57 ` [PATCH v5 01/10] mm/sparsemem: Introduce struct mem_section_usage Dan Williams
2019-03-22 16:58 ` [PATCH v5 02/10] mm/sparsemem: Introduce common definitions for the size and mask of a section Dan Williams
2019-03-22 16:58 ` [PATCH v5 03/10] mm/sparsemem: Add helpers track active portions of a section at boot Dan Williams
2019-03-22 16:58 ` [PATCH v5 04/10] mm/hotplug: Prepare shrink_{zone, pgdat}_span for sub-section removal Dan Williams
2019-03-22 16:58 ` [PATCH v5 05/10] mm/sparsemem: Convert kmalloc_section_memmap() to populate_section_memmap() Dan Williams
2019-03-22 16:58 ` [PATCH v5 06/10] mm/sparsemem: Prepare for sub-section ranges Dan Williams
2019-03-22 16:58 ` [PATCH v5 07/10] mm/sparsemem: Support sub-section hotplug Dan Williams
2019-03-22 16:58 ` [PATCH v5 08/10] mm/devm_memremap_pages: Enable sub-section remap Dan Williams
2019-03-22 16:58 ` [PATCH v5 09/10] libnvdimm/pfn: Fix fsdax-mode namespace info-block zero-fields Dan Williams
2019-03-27 14:00 ` Sasha Levin
2019-03-22 16:58 ` [PATCH v5 10/10] libnvdimm/pfn: Stop padding pmem namespaces to section alignment Dan Williams
2019-03-22 18:05 ` [PATCH v5 00/10] mm: Sub-section memory hotplug support Michal Hocko
2019-03-22 18:32 ` Dan Williams
2019-03-25 10:19 ` Michal Hocko
2019-03-25 14:28 ` Jeff Moyer
2019-03-25 14:50 ` Michal Hocko [this message]
2019-03-25 20:03 ` Dan Williams
2019-03-26 8:04 ` Michal Hocko
2019-03-27 0:20 ` Dan Williams
2019-03-27 16:13 ` Michal Hocko
2019-03-27 16:17 ` Dan Williams
2019-03-28 13:38 ` David Hildenbrand
2019-03-28 14:16 ` Michal Hocko
2019-04-01 9:18 ` David Hildenbrand
2019-03-28 20:10 ` David Hildenbrand
2019-03-28 20:43 ` Dan Williams
2019-03-28 21:17 ` David Hildenbrand
2019-03-28 21:32 ` Dan Williams
2019-03-28 21:54 ` David Hildenbrand
2019-04-10 9:51 ` David Hildenbrand
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