linux-stable.git/kernel/power/snapshot.c, branch linux-5.4.y

PM: hibernate: Clean up sync_read handling in snapshot_write_next()

2023-11-28T16:50:19+00:00

commit d08970df1980476f27936e24d452550f3e9e92e1 upstream.

In snapshot_write_next(), sync_read is set and unset in three different
spots unnecessiarly. As a result there is a subtle bug where the first
page after the meta data has been loaded unconditionally sets sync_read
to 0. If this first PFN was actually a highmem page, then the returned
buffer will be the global "buffer," and the page needs to be loaded
synchronously.

That is, I'm not sure we can always assume the following to be safe:

	handle->buffer = get_buffer(&orig_bm, &ca);
	handle->sync_read = 0;

Because get_buffer() can call get_highmem_page_buffer() which can
return 'buffer'.

The easiest way to address this is just set sync_read before
snapshot_write_next() returns if handle->buffer == buffer.

Signed-off-by: Brian Geffon 
Fixes: 8357376d3df2 ("[PATCH] swsusp: Improve handling of highmem")
Cc: All applicable 
[ rjw: Subject and changelog edits ]
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Greg Kroah-Hartman

PM: hibernate: Use __get_safe_page() rather than touching the list

2023-11-28T16:50:19+00:00

commit f0c7183008b41e92fa676406d87f18773724b48b upstream.

We found at least one situation where the safe pages list was empty and
get_buffer() would gladly try to use a NULL pointer.

Signed-off-by: Brian Geffon 
Fixes: 8357376d3df2 ("[PATCH] swsusp: Improve handling of highmem")
Cc: All applicable 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Greg Kroah-Hartman

PM: hibernate: Fix mistake in kerneldoc comment

2023-01-18T10:40:53+00:00

[ Upstream commit 6e5d7300cbe7c3541bc31f16db3e9266e6027b4b ]

The actual maximum image size formula in hibernate_preallocate_memory()
is as follows:

max_size = (count - (size + PAGES_FOR_IO)) / 2
	    - 2 * DIV_ROUND_UP(reserved_size, PAGE_SIZE);

but the one in the kerneldoc comment of the function is different and
incorrect.

Fixes: ddeb64870810 ("PM / Hibernate: Add sysfs knob to control size of memory for drivers")
Signed-off-by: xiongxin 
[ rjw: Subject and changelog rewrite ]
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Sasha Levin

PM: hibernate: Remove register_nosave_region_late()

2022-02-16T11:52:49+00:00

[ Upstream commit 33569ef3c754a82010f266b7b938a66a3ccf90a4 ]

It is an unused wrapper forcing kmalloc allocation for registering
nosave regions. Also, rename __register_nosave_region() to
register_nosave_region() now that there is no need for disambiguation.

Signed-off-by: Amadeusz Sławiński 
Reviewed-by: Cezary Rojewski 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Sasha Levin

PM: hibernate: fix crashes with init_on_free=1

2020-01-29T15:45:25+00:00

commit 18451f9f9e5810b8bd1245c5ae166f257e0e2b9d upstream.

Upon resuming from hibernation, free pages may contain stale data from
the kernel that initiated the resume. This breaks the invariant
inflicted by init_on_free=1 that freed pages must be zeroed.

To deal with this problem, make clear_free_pages() also clear the free
pages when init_on_free is enabled.

Fixes: 6471384af2a6 ("mm: security: introduce init_on_alloc=1 and init_on_free=1 boot options")
Reported-by: Johannes Stezenbach 
Signed-off-by: Alexander Potapenko 
Cc: 5.3+  # 5.3+
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Greg Kroah-Hartman

PM / hibernate: memory_bm_find_bit(): Tighten node optimisation

2020-01-09T09:19:51+00:00

[ Upstream commit da6043fe85eb5ec621e34a92540735dcebbea134 ]

When looking for a bit by number we make use of the cached result from the
preceding lookup to speed up operation.  Firstly we check if the requested
pfn is within the cached zone and if not lookup the new zone.  We then
check if the offset for that pfn falls within the existing cached node.
This happens regardless of whether the node is within the zone we are
now scanning.  With certain memory layouts it is possible for this to
false trigger creating a temporary alias for the pfn to a different bit.
This leads the hibernation code to free memory which it was never allocated
with the expected fallout.

Ensure the zone we are scanning matches the cached zone before considering
the cached node.

Deep thanks go to Andrea for many, many, many hours of hacking and testing
that went into cornering this bug.

Reported-by: Andrea Righi 
Tested-by: Andrea Righi 
Signed-off-by: Andy Whitcroft 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Sasha Levin

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 428

2019-06-05T15:37:16+00:00

Based on 1 normalized pattern(s):

  this file is released under the gplv2

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 68 file(s).

Signed-off-by: Thomas Gleixner 
Reviewed-by: Armijn Hemel 
Reviewed-by: Allison Randal 
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190531190114.292346262@linutronix.de
Signed-off-by: Greg Kroah-Hartman

mm/hibernation: Make hibernation handle unmapped pages

2019-04-30T10:37:57+00:00

Make hibernate handle unmapped pages on the direct map when
CONFIG_ARCH_HAS_SET_ALIAS=y is set. These functions allow for setting pages
to invalid configurations, so now hibernate should check if the pages have
valid mappings and handle if they are unmapped when doing a hibernate
save operation.

Previously this checking was already done when CONFIG_DEBUG_PAGEALLOC=y
was configured. It does not appear to have a big hibernating performance
impact. The speed of the saving operation before this change was measured
as 819.02 MB/s, and after was measured at 813.32 MB/s.

Before:
[    4.670938] PM: Wrote 171996 kbytes in 0.21 seconds (819.02 MB/s)

After:
[    4.504714] PM: Wrote 178932 kbytes in 0.22 seconds (813.32 MB/s)

Signed-off-by: Rick Edgecombe 
Signed-off-by: Peter Zijlstra (Intel) 
Acked-by: Pavel Machek 
Cc: 
Cc: 
Cc: 
Cc: 
Cc: 
Cc: 
Cc: 
Cc: Andy Lutomirski 
Cc: Borislav Petkov 
Cc: Dave Hansen 
Cc: H. Peter Anvin 
Cc: Linus Torvalds 
Cc: Nadav Amit 
Cc: Rafael J. Wysocki 
Cc: Rik van Riel 
Cc: Thomas Gleixner 
Link: https://lkml.kernel.org/r/20190426001143.4983-16-namit@vmware.com
Signed-off-by: Ingo Molnar

treewide: add checks for the return value of memblock_alloc*()

2019-03-12T17:04:02+00:00

Add check for the return value of memblock_alloc*() functions and call
panic() in case of error.  The panic message repeats the one used by
panicing memblock allocators with adjustment of parameters to include
only relevant ones.

The replacement was mostly automated with semantic patches like the one
below with manual massaging of format strings.

  @@
  expression ptr, size, align;
  @@
  ptr = memblock_alloc(size, align);
  + if (!ptr)
  + 	panic("%s: Failed to allocate %lu bytes align=0x%lx\n", __func__, size, align);

[anders.roxell@linaro.org: use '%pa' with 'phys_addr_t' type]
  Link: http://lkml.kernel.org/r/20190131161046.21886-1-anders.roxell@linaro.org
[rppt@linux.ibm.com: fix format strings for panics after memblock_alloc]
  Link: http://lkml.kernel.org/r/1548950940-15145-1-git-send-email-rppt@linux.ibm.com
[rppt@linux.ibm.com: don't panic if the allocation in sparse_buffer_init fails]
  Link: http://lkml.kernel.org/r/20190131074018.GD28876@rapoport-lnx
[akpm@linux-foundation.org: fix xtensa printk warning]
Link: http://lkml.kernel.org/r/1548057848-15136-20-git-send-email-rppt@linux.ibm.com
Signed-off-by: Mike Rapoport 
Signed-off-by: Anders Roxell 
Reviewed-by: Guo Ren 		[c-sky]
Acked-by: Paul Burton 		[MIPS]
Acked-by: Heiko Carstens 	[s390]
Reviewed-by: Juergen Gross 		[Xen]
Reviewed-by: Geert Uytterhoeven 	[m68k]
Acked-by: Max Filippov 		[xtensa]
Cc: Catalin Marinas 
Cc: Christophe Leroy 
Cc: Christoph Hellwig 
Cc: "David S. Miller" 
Cc: Dennis Zhou 
Cc: Greentime Hu 
Cc: Greg Kroah-Hartman 
Cc: Guan Xuetao 
Cc: Guo Ren 
Cc: Mark Salter 
Cc: Matt Turner 
Cc: Michael Ellerman 
Cc: Michal Simek 
Cc: Petr Mladek 
Cc: Richard Weinberger 
Cc: Rich Felker 
Cc: Rob Herring 
Cc: Rob Herring 
Cc: Russell King 
Cc: Stafford Horne 
Cc: Tony Luck 
Cc: Vineet Gupta 
Cc: Yoshinori Sato 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

PM/Hibernate: exclude all PageOffline() pages

2019-03-06T05:07:14+00:00

The content of pages that are marked PG_offline is not of interest (e.g.
inflated by a balloon driver), let's skip these pages.

In saveable_highmem_page(), move the PageReserved() check to a new check
along with the PageOffline() check to separate it from the swsusp
checks.

[david@redhat.com: v2]
  Link: http://lkml.kernel.org/r/20181122100627.5189-9-david@redhat.com
Link: http://lkml.kernel.org/r/20181119101616.8901-9-david@redhat.com
Signed-off-by: David Hildenbrand 
Acked-by: Pavel Machek 
Acked-by: Rafael J. Wysocki 
Cc: Pavel Machek 
Cc: Len Brown 
Cc: Matthew Wilcox 
Cc: Michal Hocko 
Cc: "Michael S. Tsirkin" 
Cc: Alexander Duyck 
Cc: Alexey Dobriyan 
Cc: Arnd Bergmann 
Cc: Baoquan He 
Cc: Borislav Petkov 
Cc: Boris Ostrovsky 
Cc: Christian Hansen 
Cc: Dave Young 
Cc: David Rientjes 
Cc: Greg Kroah-Hartman 
Cc: Haiyang Zhang 
Cc: Jonathan Corbet 
Cc: Juergen Gross 
Cc: Julien Freche 
Cc: Kairui Song 
Cc: Kazuhito Hagio 
Cc: "Kirill A. Shutemov" 
Cc: Konstantin Khlebnikov 
Cc: "K. Y. Srinivasan" 
Cc: Lianbo Jiang 
Cc: Michal Hocko 
Cc: Mike Rapoport 
Cc: Miles Chen 
Cc: Nadav Amit 
Cc: Naoya Horiguchi 
Cc: Omar Sandoval 
Cc: Pankaj gupta 
Cc: Pavel Tatashin 
Cc: "Rafael J. Wysocki" 
Cc: Stefano Stabellini 
Cc: Stephen Hemminger 
Cc: Stephen Rothwell 
Cc: Vitaly Kuznetsov 
Cc: Vlastimil Babka 
Cc: Xavier Deguillard 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds