linux.git/drivers/base/memory.c, branch v5.4-rc4

drivers/base/memory.c: don't access uninitialized memmaps in soft_offline_page_store()

2019-10-19T10:32:31+00:00

Uninitialized memmaps contain garbage and in the worst case trigger kernel
BUGs, especially with CONFIG_PAGE_POISONING.  They should not get touched.

Right now, when trying to soft-offline a PFN that resides on a memory
block that was never onlined, one gets a misleading error with
CONFIG_PAGE_POISONING:

  :/# echo 5637144576 > /sys/devices/system/memory/soft_offline_page
  [   23.097167] soft offline: 0x150000 page already poisoned

But the actual result depends on the garbage in the memmap.

soft_offline_page() can only work with online pages, it returns -EIO in
case of ZONE_DEVICE.  Make sure to only forward pages that are online
(iow, managed by the buddy) and, therefore, have an initialized memmap.

Add a check against pfn_to_online_page() and similarly return -EIO.

Link: http://lkml.kernel.org/r/20191010141200.8985-1-david@redhat.com
Fixes: f1dd2cd13c4b ("mm, memory_hotplug: do not associate hotadded memory to zones until online")	[visible after d0dc12e86b319]
Signed-off-by: David Hildenbrand 
Acked-by: Naoya Horiguchi 
Acked-by: Michal Hocko 
Cc: Greg Kroah-Hartman 
Cc: "Rafael J. Wysocki" 
Cc: 	[4.13+]
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

drivers/base/memory.c: don't store end_section_nr in memory blocks

2019-09-24T22:54:09+00:00

Each memory block spans the same amount of sections/pages/bytes.  The size
is determined before the first memory block is created.  No need to store
what we can easily calculate - and the calculations even look simpler now.

Michal brought up the idea of variable-sized memory blocks.  However, if
we ever implement something like this, we will need an API compatibility
switch and reworks at various places (most code assumes a fixed memory
block size).  So let's cleanup what we have right now.

While at it, fix the variable naming in register_mem_sect_under_node() -
we no longer talk about a single section.

Link: http://lkml.kernel.org/r/20190809110200.2746-1-david@redhat.com
Signed-off-by: David Hildenbrand 
Cc: Greg Kroah-Hartman 
Cc: "Rafael J. Wysocki" 
Cc: Pavel Tatashin 
Cc: Michal Hocko 
Cc: Dan Williams 
Cc: Oscar Salvador 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

driver/base/memory.c: validate memory block size early

2019-09-24T22:54:09+00:00

Let's validate the memory block size early, when initializing the memory
device infrastructure.  Fail hard in case the value is not suitable.

As nobody checks the return value of memory_dev_init(), turn it into a
void function and fail with a panic in all scenarios instead.  Otherwise,
we'll crash later during boot when core/drivers expect that the memory
device infrastructure (including memory_block_size_bytes()) works as
expected.

I think long term, we should move the whole memory block size
configuration (set_memory_block_size_order() and
memory_block_size_bytes()) into drivers/base/memory.c.

Link: http://lkml.kernel.org/r/20190806090142.22709-1-david@redhat.com
Signed-off-by: David Hildenbrand 
Cc: Greg Kroah-Hartman 
Cc: "Rafael J. Wysocki" 
Cc: Pavel Tatashin 
Cc: Michal Hocko 
Cc: Dan Williams 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

drivers/base/memory.c: fixup documentation of removable/phys_index/block_size_bytes

2019-09-24T22:54:09+00:00

Let's rephrase to memory block terminology and add some further
clarifications.

Link: http://lkml.kernel.org/r/20190806080826.5963-1-david@redhat.com
Signed-off-by: David Hildenbrand 
Reviewed-by: Andrew Morton 
Cc: Greg Kroah-Hartman 
Cc: "Rafael J. Wysocki" 
Cc: Michal Hocko 
Cc: Oscar Salvador 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

drivers/base/node.c: simplify unregister_memory_block_under_nodes()

2019-09-24T22:54:09+00:00

We don't allow to offline memory block devices that belong to multiple
numa nodes.  Therefore, such devices can never get removed.  It is
sufficient to process a single node when removing the memory block.  No
need to iterate over each and every PFN.

We already have the nid stored for each memory block.  Make sure that the
nid always has a sane value.

Please note that checking for node_online(nid) is not required.  If we
would have a memory block belonging to a node that is no longer offline,
then we would have a BUG in the node offlining code.

Link: http://lkml.kernel.org/r/20190719135244.15242-1-david@redhat.com
Signed-off-by: David Hildenbrand 
Cc: Greg Kroah-Hartman 
Cc: "Rafael J. Wysocki" 
Cc: David Hildenbrand 
Cc: Stephen Rothwell 
Cc: Pavel Tatashin 
Cc: Michal Hocko 
Cc: Oscar Salvador 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

drivers/base/memory.c: get rid of find_memory_block_hinted()

2019-07-19T00:08:07+00:00

No longer needed, let's remove it.  Also, drop the "hint" parameter
completely from "find_memory_block_by_id", as nobody needs it anymore.

[david@redhat.com: v3]
  Link: http://lkml.kernel.org/r/20190620183139.4352-7-david@redhat.com
[david@redhat.com: handle zero-length walks]
  Link: http://lkml.kernel.org/r/1c2edc22-afd7-2211-c4c7-40e54e5007e8@redhat.com
Link: http://lkml.kernel.org/r/20190614100114.311-7-david@redhat.com
Signed-off-by: David Hildenbrand 
Reviewed-by: Andrew Morton 
Tested-by: Qian Cai 
Cc: Greg Kroah-Hartman 
Cc: "Rafael J. Wysocki" 
Cc: David Hildenbrand 
Cc: Stephen Rothwell 
Cc: Pavel Tatashin 
Cc: Andrew Banman 
Cc: Mike Travis 
Cc: Oscar Salvador 
Cc: Michal Hocko 
Cc: Wei Yang 
Cc: Arun KS 
Cc: Stephen Rothwell 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm/memory_hotplug: move and simplify walk_memory_blocks()

2019-07-19T00:08:06+00:00

Let's move walk_memory_blocks() to the place where memory block logic
resides and simplify it.  While at it, add a type for the callback
function.

Link: http://lkml.kernel.org/r/20190614100114.311-6-david@redhat.com
Signed-off-by: David Hildenbrand 
Reviewed-by: Andrew Morton 
Cc: Greg Kroah-Hartman 
Cc: "Rafael J. Wysocki" 
Cc: David Hildenbrand 
Cc: Stephen Rothwell 
Cc: Pavel Tatashin 
Cc: Andrew Banman 
Cc: Mike Travis 
Cc: Oscar Salvador 
Cc: Michal Hocko 
Cc: Wei Yang 
Cc: Arun KS 
Cc: Qian Cai 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

drivers/base/memory: use "unsigned long" for block ids

2019-07-19T00:08:06+00:00

Block ids are just shifted section numbers, so let's also use "unsigned
long" for them, too.

Link: http://lkml.kernel.org/r/20190614100114.311-3-david@redhat.com
Signed-off-by: David Hildenbrand 
Reviewed-by: Andrew Morton 
Cc: Greg Kroah-Hartman 
Cc: "Rafael J. Wysocki" 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm: section numbers use the type "unsigned long"

2019-07-19T00:08:06+00:00

Patch series "mm: Further memory block device cleanups", v1.

Some further cleanups around memory block devices.  Especially, clean up
and simplify walk_memory_range().  Including some other minor cleanups.

This patch (of 6):

We are using a mixture of "int" and "unsigned long".  Let's make this
consistent by using "unsigned long" everywhere.  We'll do the same with
memory block ids next.

While at it, turn the "unsigned long i" in removable_show() into an int
- sections_per_block is an int.

[akpm@linux-foundation.org: s/unsigned long i/unsigned long nr/]
[david@redhat.com: v3]
  Link: http://lkml.kernel.org/r/20190620183139.4352-2-david@redhat.com
Link: http://lkml.kernel.org/r/20190614100114.311-2-david@redhat.com
Signed-off-by: David Hildenbrand 
Reviewed-by: Andrew Morton 
Cc: Greg Kroah-Hartman 
Cc: "Rafael J. Wysocki" 
Cc: Vlastimil Babka 
Cc: Michal Hocko 
Cc: Dan Williams 
Cc: Mel Gorman 
Cc: Wei Yang 
Cc: Johannes Weiner 
Cc: Arun KS 
Cc: Pavel Tatashin 
Cc: Oscar Salvador 
Cc: Stephen Rothwell 
Cc: Mike Rapoport 
Cc: Baoquan He 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm/memory_hotplug: remove memory block devices before arch_remove_memory()

2019-07-19T00:08:06+00:00

Let's factor out removing of memory block devices, which is only
necessary for memory added via add_memory() and friends that created
memory block devices.  Remove the devices before calling
arch_remove_memory().

This finishes factoring out memory block device handling from
arch_add_memory() and arch_remove_memory().

Link: http://lkml.kernel.org/r/20190527111152.16324-10-david@redhat.com
Signed-off-by: David Hildenbrand 
Reviewed-by: Dan Williams 
Acked-by: Michal Hocko 
Cc: Greg Kroah-Hartman 
Cc: "Rafael J. Wysocki" 
Cc: David Hildenbrand 
Cc: "mike.travis@hpe.com" 
Cc: Andrew Banman 
Cc: Ingo Molnar 
Cc: Alex Deucher 
Cc: "David S. Miller" 
Cc: Mark Brown 
Cc: Chris Wilson 
Cc: Oscar Salvador 
Cc: Jonathan Cameron 
Cc: Arun KS 
Cc: Mathieu Malaterre 
Cc: Andy Lutomirski 
Cc: Anshuman Khandual 
Cc: Ard Biesheuvel 
Cc: Baoquan He 
Cc: Benjamin Herrenschmidt 
Cc: Borislav Petkov 
Cc: Catalin Marinas 
Cc: Chintan Pandya 
Cc: Christophe Leroy 
Cc: Dave Hansen 
Cc: Fenghua Yu 
Cc: Heiko Carstens 
Cc: "H. Peter Anvin" 
Cc: Joonsoo Kim 
Cc: Jun Yao 
Cc: "Kirill A. Shutemov" 
Cc: Logan Gunthorpe 
Cc: Mark Rutland 
Cc: Masahiro Yamada 
Cc: Michael Ellerman 
Cc: Mike Rapoport 
Cc: Nicholas Piggin 
Cc: Oscar Salvador 
Cc: Paul Mackerras 
Cc: Pavel Tatashin 
Cc: Peter Zijlstra 
Cc: Qian Cai 
Cc: Rich Felker 
Cc: Rob Herring 
Cc: Robin Murphy 
Cc: Thomas Gleixner 
Cc: Tony Luck 
Cc: Vasily Gorbik 
Cc: Wei Yang 
Cc: Will Deacon 
Cc: Yoshinori Sato 
Cc: Yu Zhao 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds