Memory hotlug is broken for 32b systems at least since c6f03e2903 ("mm,
memory_hotplug: remove zone restrictions") which has considerably reworked
how can be memory associated with movable/kernel zones. The same is not
really trivial to achieve in 32b where only lowmem is the kernel zone.
While we can tweak this immediate problem around there are likely other
land mines hidden at other places.
It is also quite dubious that there is a real usecase for the memory
hotplug on 32b in the first place. Low memory is just too small to be
hotplugable (for hot add) and generally unusable for hotremove. Adding
more memory to highmem is also dubious because it would increase the low
mem or vmalloc space pressure for memmaps.
Restrict the functionality to 64b systems. This will help future
development to focus on usecases that have real life application. We can
remove this restriction in future in presence of a real life usecase of
course but until then make it explicit that hotplug on 32b is broken and
requires a non trivial amount of work to fix.
Robin said:
"32-bit Arm doesn't support memory hotplug, and as far as I'm aware
there's little likelihood of it ever wanting to. FWIW it looks like
SuperH is the only pure-32-bit architecture to have hotplug support at
all"
Signed-off-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Baoquan He <bhe@redhat.com>
Cc: Wei Yang <richardw.yang@linux.intel.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Vamshi K Sthambamkadi <vamshi.k.sthambamkadi@gmail.com>
Link: http://lkml.kernel.org/r/20200218100532.GA4151@dhcp22.suse.cz
Link: https://bugzilla.kernel.org/show_bug.cgi?id=206401
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently, when adding memory, we create entries in /sys/firmware/memmap/
as "System RAM". This will lead to kexec-tools to add that memory to the
fixed-up initial memmap for a kexec kernel (loaded via kexec_load()). The
memory will be considered initial System RAM by the kexec'd kernel and can
no longer be reconfigured. This is not what happens during a real reboot.
Let's add our memory via add_memory_driver_managed() now, so we won't
create entries in /sys/firmware/memmap/ and indicate the memory as "System
RAM (kmem)" in /proc/iomem. This allows everybody (especially
kexec-tools) to identify that this memory is special and has to be treated
differently than ordinary (hotplugged) System RAM.
Before configuring the namespace:
[root@localhost ~]# cat /proc/iomem
...
140000000-33fffffff : Persistent Memory
140000000-33fffffff : namespace0.0
3280000000-32ffffffff : PCI Bus 0000:00
After configuring the namespace:
[root@localhost ~]# cat /proc/iomem
...
140000000-33fffffff : Persistent Memory
140000000-1481fffff : namespace0.0
148200000-33fffffff : dax0.0
3280000000-32ffffffff : PCI Bus 0000:00
After loading kmem before this change:
[root@localhost ~]# cat /proc/iomem
...
140000000-33fffffff : Persistent Memory
140000000-1481fffff : namespace0.0
150000000-33fffffff : dax0.0
150000000-33fffffff : System RAM
3280000000-32ffffffff : PCI Bus 0000:00
After loading kmem after this change:
[root@localhost ~]# cat /proc/iomem
...
140000000-33fffffff : Persistent Memory
140000000-1481fffff : namespace0.0
150000000-33fffffff : dax0.0
150000000-33fffffff : System RAM (kmem)
3280000000-32ffffffff : PCI Bus 0000:00
After a proper reboot:
[root@localhost ~]# cat /proc/iomem
...
140000000-33fffffff : Persistent Memory
140000000-1481fffff : namespace0.0
148200000-33fffffff : dax0.0
3280000000-32ffffffff : PCI Bus 0000:00
Within the kexec kernel before this change:
[root@localhost ~]# cat /proc/iomem
...
140000000-33fffffff : Persistent Memory
140000000-1481fffff : namespace0.0
150000000-33fffffff : System RAM
3280000000-32ffffffff : PCI Bus 0000:00
Within the kexec kernel after this change:
[root@localhost ~]# cat /proc/iomem
...
140000000-33fffffff : Persistent Memory
140000000-1481fffff : namespace0.0
148200000-33fffffff : dax0.0
3280000000-32ffffffff : PCI Bus 0000:00
/sys/firmware/memmap/ before this change:
0000000000000000-000000000009fc00 (System RAM)
000000000009fc00-00000000000a0000 (Reserved)
00000000000f0000-0000000000100000 (Reserved)
0000000000100000-00000000bffdf000 (System RAM)
00000000bffdf000-00000000c0000000 (Reserved)
00000000feffc000-00000000ff000000 (Reserved)
00000000fffc0000-0000000100000000 (Reserved)
0000000100000000-0000000140000000 (System RAM)
0000000150000000-0000000340000000 (System RAM)
/sys/firmware/memmap/ after a proper reboot:
0000000000000000-000000000009fc00 (System RAM)
000000000009fc00-00000000000a0000 (Reserved)
00000000000f0000-0000000000100000 (Reserved)
0000000000100000-00000000bffdf000 (System RAM)
00000000bffdf000-00000000c0000000 (Reserved)
00000000feffc000-00000000ff000000 (Reserved)
00000000fffc0000-0000000100000000 (Reserved)
0000000100000000-0000000140000000 (System RAM)
/sys/firmware/memmap/ after this change:
0000000000000000-000000000009fc00 (System RAM)
000000000009fc00-00000000000a0000 (Reserved)
00000000000f0000-0000000000100000 (Reserved)
0000000000100000-00000000bffdf000 (System RAM)
00000000bffdf000-00000000c0000000 (Reserved)
00000000feffc000-00000000ff000000 (Reserved)
00000000fffc0000-0000000100000000 (Reserved)
0000000100000000-0000000140000000 (System RAM)
kexec-tools already seem to basically ignore any System RAM that's not on
top level when searching for areas to place kexec images - but also for
determining crash areas to dump via kdump. Changing the resource name
won't have an impact.
Handle unloading of the driver after memory hotremove failed properly, by
duplicating the string if necessary.
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Link: http://lkml.kernel.org/r/20200508084217.9160-5-david@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Memory flagged with IORESOURCE_MEM_DRIVER_MANAGED is special - it won't be
part of the initial memmap of the kexec kernel and not all memory might be
accessible. Don't place any kexec images onto it.
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Link: http://lkml.kernel.org/r/20200508084217.9160-4-david@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "mm/memory_hotplug: Interface to add driver-managed system
ram", v4.
kexec (via kexec_load()) can currently not properly handle memory added
via dax/kmem, and will have similar issues with virtio-mem. kexec-tools
will currently add all memory to the fixed-up initial firmware memmap. In
case of dax/kmem, this means that - in contrast to a proper reboot - how
that persistent memory will be used can no longer be configured by the
kexec'd kernel. In case of virtio-mem it will be harmful, because that
memory might contain inaccessible pieces that require coordination with
hypervisor first.
In both cases, we want to let the driver in the kexec'd kernel handle
detecting and adding the memory, like during an ordinary reboot.
Introduce add_memory_driver_managed(). More on the samentics are in patch
#1.
In the future, we might want to make this behavior configurable for
dax/kmem- either by configuring it in the kernel (which would then also
allow to configure kexec_file_load()) or in kexec-tools by also adding
"System RAM (kmem)" memory from /proc/iomem to the fixed-up initial
firmware memmap.
More on the motivation can be found in [1] and [2].
[1] https://lkml.kernel.org/r/20200429160803.109056-1-david@redhat.com
[2] https://lkml.kernel.org/r/20200430102908.10107-1-david@redhat.com
This patch (of 3):
Some device drivers rely on memory they managed to not get added to the
initial (firmware) memmap as system RAM - so it's not used as initial
system RAM by the kernel and the driver is under control. While this is
the case during cold boot and after a reboot, kexec is not aware of that
and might add such memory to the initial (firmware) memmap of the kexec
kernel. We need ways to teach kernel and userspace that this system ram
is different.
For example, dax/kmem allows to decide at runtime if persistent memory is
to be used as system ram. Another future user is virtio-mem, which has to
coordinate with its hypervisor to deal with inaccessible parts within
memory resources.
We want to let users in the kernel (esp. kexec) but also user space
(esp. kexec-tools) know that this memory has different semantics and
needs to be handled differently:
1. Don't create entries in /sys/firmware/memmap/
2. Name the memory resource "System RAM ($DRIVER)" (exposed via
/proc/iomem) ($DRIVER might be "kmem", "virtio_mem").
3. Flag the memory resource IORESOURCE_MEM_DRIVER_MANAGED
/sys/firmware/memmap/ [1] represents the "raw firmware-provided memory
map" because "on most architectures that firmware-provided memory map is
modified afterwards by the kernel itself". The primary user is kexec on
x86-64. Since commit d96ae53091 ("memory-hotplug: create
/sys/firmware/memmap entry for new memory"), we add all hotplugged memory
to that firmware memmap - which makes perfect sense for traditional memory
hotplug on x86-64, where real HW will also add hotplugged DIMMs to the
firmware memmap. We replicate what the "raw firmware-provided memory map"
looks like after hot(un)plug.
To keep things simple, let the user provide the full resource name instead
of only the driver name - this way, we don't have to manually
allocate/craft strings for memory resources. Also use the resource name
to make decisions, to avoid passing additional flags. In case the name
isn't "System RAM", it's special.
We don't have to worry about firmware_map_remove() on the removal path.
If there is no entry, it will simply return with -EINVAL.
We'll adapt dax/kmem in a follow-up patch.
[1] https://www.kernel.org/doc/Documentation/ABI/testing/sysfs-firmware-memmap
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Link: http://lkml.kernel.org/r/20200508084217.9160-1-david@redhat.com
Link: http://lkml.kernel.org/r/20200508084217.9160-3-david@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The comment in add_memory_resource() is stale: hotadd_new_pgdat() will no
longer call get_pfn_range_for_nid(), as a hotadded pgdat will simply span
no pages at all, until memory is moved to the zone/node via
move_pfn_range_to_zone() - e.g., when onlining memory blocks.
The only archs that care about memblocks for hotplugged memory (either for
iterating over all system RAM or testing for memory validity) are arm64,
s390x, and powerpc - due to CONFIG_ARCH_KEEP_MEMBLOCK. Without
CONFIG_ARCH_KEEP_MEMBLOCK, we can simply stop messing with memblocks.
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Link: http://lkml.kernel.org/r/20200422155353.25381-3-david@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "mm/memory_hotplug: handle memblocks only with
CONFIG_ARCH_KEEP_MEMBLOCK", v1.
A hotadded node/pgdat will span no pages at all, until memory is moved to
the zone/node via move_pfn_range_to_zone() -> resize_pgdat_range - e.g.,
when onlining memory blocks. We don't have to initialize the
node_start_pfn to the memory we are adding.
This patch (of 2):
Especially, there is an inconsistency:
- Hotplugging memory to a memory-less node with cpus: node_start_pf == 0
- Offlining and removing last memory from a node: node_start_pfn == 0
- Hotplugging memory to a memory-less node without cpus: node_start_pfn != 0
As soon as memory is onlined, node_start_pfn is overwritten with the
actual start. E.g., when adding two DIMMs but only onlining one of both,
only that DIMM (with online memory blocks) is spanned by the node.
Currently, the validity of node_start_pfn really is linked to
node_spanned_pages != 0. With node_spanned_pages == 0 (e.g., before
onlining memory), it has no meaning.
So let's stop setting node_start_pfn, just to be overwritten via
move_pfn_range_to_zone(). This avoids confusion when looking at the code,
wondering which magic will be performed with the node_start_pfn in this
function, when hotadding a pgdat.
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Michal Hocko <mhocko@suse.com>
Link: http://lkml.kernel.org/r/20200422155353.25381-1-david@redhat.com
Link: http://lkml.kernel.org/r/20200422155353.25381-2-david@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fortunately, all users of is_mem_section_removable() are gone. Get rid of
it, including some now unnecessary functions.
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Wei Yang <richard.weiyang@gmail.com>
Reviewed-by: Baoquan He <bhe@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Oscar Salvador <osalvador@suse.de>
Link: http://lkml.kernel.org/r/20200407135416.24093-3-david@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In commit 53cdc1cb29 ("drivers/base/memory.c: indicate all memory blocks
as removable"), the user space interface to compute whether a memory block
can be offlined (exposed via /sys/devices/system/memory/memoryX/removable)
has effectively been deprecated. We want to remove the leftovers of the
kernel implementation.
When offlining a memory block (mm/memory_hotplug.c:__offline_pages()),
we'll start by:
1. Testing if it contains any holes, and reject if so
2. Testing if pages belong to different zones, and reject if so
3. Isolating the page range, checking if it contains any unmovable pages
Using is_mem_section_removable() before trying to offline is not only
racy, it can easily result in false positives/negatives. Let's stop
manually checking is_mem_section_removable(), and let device_offline()
handle it completely instead. We can remove the racy
is_mem_section_removable() implementation next.
We now take more locks (e.g., memory hotplug lock when offlining and the
zone lock when isolating), but maybe we should optimize that
implementation instead if this ever becomes a real problem (after all,
memory unplug is already an expensive operation). We started using
is_mem_section_removable() in commit 51925fb3c5 ("powerpc/pseries:
Implement memory hotplug remove in the kernel"), with the initial
hotremove support of lmbs.
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Baoquan He <bhe@redhat.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Link: http://lkml.kernel.org/r/20200407135416.24093-2-david@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
For kvmalloc'ed data object that contains sensitive information like
cryptographic keys, we need to make sure that the buffer is always cleared
before freeing it. Using memset() alone for buffer clearing may not
provide certainty as the compiler may compile it away. To be sure, the
special memzero_explicit() has to be used.
This patch introduces a new kvfree_sensitive() for freeing those sensitive
data objects allocated by kvmalloc(). The relevant places where
kvfree_sensitive() can be used are modified to use it.
Fixes: 4f0882491a ("KEYS: Avoid false positive ENOMEM error on key read")
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Acked-by: David Howells <dhowells@redhat.com>
Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Cc: James Morris <jmorris@namei.org>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: Joe Perches <joe@perches.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Uladzislau Rezki <urezki@gmail.com>
Link: http://lkml.kernel.org/r/20200407200318.11711-1-longman@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Most architectures define kmap_prot to be PAGE_KERNEL.
Let sparc and xtensa define there own and define PAGE_KERNEL as the
default if not overridden.
[akpm@linux-foundation.org: coding style fixes]
Suggested-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Christian König <christian.koenig@amd.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Helge Deller <deller@gmx.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20200507150004.1423069-16-ira.weiny@intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
linux/highmem.h has not been needed for the pte_offset_map => kmap_atomic
use in sparc for some time (~2002)
Remove this include.
Suggested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Christian König <christian.koenig@amd.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Chris Zankel <chris@zankel.net>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Helge Deller <deller@gmx.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20200507150004.1423069-15-ira.weiny@intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
parisc reimplements the kmap calls except to flush its dcache. This is
arguably an abuse of kmap but regardless it is messy and confusing.
Remove the duplicate code and have parisc define ARCH_HAS_FLUSH_ON_KUNMAP
for a kunmap_flush_on_unmap() architecture specific call to flush the
cache.
Suggested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Christian König <christian.koenig@amd.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Chris Zankel <chris@zankel.net>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Helge Deller <deller@gmx.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20200507150004.1423069-14-ira.weiny@intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
kmap_atomic_to_page() has no callers and is only defined on 1 arch and
declared on another. Remove it.
Suggested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Christian König <christian.koenig@amd.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Chris Zankel <chris@zankel.net>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Helge Deller <deller@gmx.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20200507150004.1423069-13-ira.weiny@intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
kmap_atomic_prot() is now exported by all architectures. Use this
function rather than open coding a driver specific kmap_atomic.
[arnd@arndb.de: include linux/highmem.h]
Link: http://lkml.kernel.org/r/20200508220150.649044-1-arnd@arndb.de
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Chris Zankel <chris@zankel.net>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Helge Deller <deller@gmx.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20200507150004.1423069-12-ira.weiny@intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
To support kmap_atomic_prot(), all architectures need to support
protections passed to their kmap_atomic_high() function. Pass protections
into kmap_atomic_high() and change the name to kmap_atomic_high_prot() to
match.
Then define kmap_atomic_prot() as a core function which calls
kmap_atomic_high_prot() when needed.
Finally, redefine kmap_atomic() as a wrapper of kmap_atomic_prot() with
the default kmap_prot exported by the architectures.
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Christian König <christian.koenig@amd.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Helge Deller <deller@gmx.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20200507150004.1423069-11-ira.weiny@intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
To support kmap_atomic_prot() on all architectures each arch must support
protections passed in to them.
Change csky, mips, nds32 and xtensa to use their global constant kmap_prot
rather than a hard coded value which was equal.
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Christian König <christian.koenig@amd.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Helge Deller <deller@gmx.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20200507150004.1423069-10-ira.weiny@intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We want to support kmap_atomic_prot() on all architectures and it makes
sense to define kmap_atomic() to use the default kmap_prot.
So we ensure all arch's have a globally available kmap_prot either as a
define or exported symbol.
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Christian König <christian.koenig@amd.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Helge Deller <deller@gmx.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20200507150004.1423069-9-ira.weiny@intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Every single architecture (including !CONFIG_HIGHMEM) calls...
pagefault_enable();
preempt_enable();
... before returning from __kunmap_atomic(). Lift this code into the
kunmap_atomic() macro.
While we are at it rename __kunmap_atomic() to kunmap_atomic_high() to
be consistent.
[ira.weiny@intel.com: don't enable pagefault/preempt twice]
Link: http://lkml.kernel.org/r/20200518184843.3029640-1-ira.weiny@intel.com
[akpm@linux-foundation.org: coding style fixes]
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Christian König <christian.koenig@amd.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Helge Deller <deller@gmx.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Guenter Roeck <linux@roeck-us.net>
Link: http://lkml.kernel.org/r/20200507150004.1423069-8-ira.weiny@intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Every arch has the same code to ensure atomic operations and a check for
!HIGHMEM page.
Remove the duplicate code by defining a core kmap_atomic() which only
calls the arch specific kmap_atomic_high() when the page is high memory.
[akpm@linux-foundation.org: coding style fixes]
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Christian König <christian.koenig@amd.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Helge Deller <deller@gmx.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20200507150004.1423069-7-ira.weiny@intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
During this kmap() conversion series we must maintain bisect-ability. To
do this, kmap_atomic_prot() in x86, powerpc, and microblaze need to remain
functional.
Create a temporary inline version of kmap_atomic_prot within these
architectures so we can rework their kmap_atomic() calls and then lift
kmap_atomic_prot() to the core.
Suggested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Christian König <christian.koenig@amd.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Helge Deller <deller@gmx.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20200507150004.1423069-6-ira.weiny@intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
All architectures do exactly the same thing for kunmap(); remove all the
duplicate definitions and lift the call to the core.
This also has the benefit of changing kmap_unmap() on a number of
architectures to be an inline call rather than an actual function.
[akpm@linux-foundation.org: fix CONFIG_HIGHMEM=n build on various architectures]
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Christian König <christian.koenig@amd.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Helge Deller <deller@gmx.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20200507150004.1423069-5-ira.weiny@intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The kmap code for all the architectures is almost 100% identical.
Lift the common code to the core. Use ARCH_HAS_KMAP_FLUSH_TLB to indicate
if an arch defines kmap_flush_tlb() and call if if needed.
This also has the benefit of changing kmap() on a number of architectures
to be an inline call rather than an actual function.
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Christian König <christian.koenig@amd.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Helge Deller <deller@gmx.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20200507150004.1423069-4-ira.weiny@intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Move the kmap() build bug to kmap_init() to facilitate patches to lift
kmap() to the core.
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Christian König <christian.koenig@amd.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Helge Deller <deller@gmx.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20200507150004.1423069-3-ira.weiny@intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "Remove duplicated kmap code", v3.
The kmap infrastructure has been copied almost verbatim to every
architecture. This series consolidates obvious duplicated code by
defining core functions which call into the architectures only when
needed.
Some of the k[un]map_atomic() implementations have some similarities but
the similarities were not sufficient to warrant further changes.
In addition we remove a duplicate implementation of kmap() in DRM.
This patch (of 15):
Replace the use of BUG_ON(in_interrupt()) in the kmap() and kunmap() in
favor of might_sleep().
Besides the benefits of might_sleep(), this normalizes the implementations
such that they can be made generic in subsequent patches.
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christian König <christian.koenig@amd.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Chris Zankel <chris@zankel.net>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Link: http://lkml.kernel.org/r/20200507150004.1423069-1-ira.weiny@intel.com
Link: http://lkml.kernel.org/r/20200507150004.1423069-2-ira.weiny@intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There is a typo in comment, fix it.
"nother" -> "another"
Signed-off-by: Jeongtae Park <jtp.park@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Christoph Hellwig <hch@lst.de>
Link: http://lkml.kernel.org/r/20200604185239.20765-1-jtp.park@samsung.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This adds tests which will validate architecture page table helpers and
other accessors in their compliance with expected generic MM semantics.
This will help various architectures in validating changes to existing
page table helpers or addition of new ones.
This test covers basic page table entry transformations including but not
limited to old, young, dirty, clean, write, write protect etc at various
level along with populating intermediate entries with next page table page
and validating them.
Test page table pages are allocated from system memory with required size
and alignments. The mapped pfns at page table levels are derived from a
real pfn representing a valid kernel text symbol. This test gets called
via late_initcall().
This test gets built and run when CONFIG_DEBUG_VM_PGTABLE is selected.
Any architecture, which is willing to subscribe this test will need to
select ARCH_HAS_DEBUG_VM_PGTABLE. For now this is limited to arc, arm64,
x86, s390 and powerpc platforms where the test is known to build and run
successfully Going forward, other architectures too can subscribe the test
after fixing any build or runtime problems with their page table helpers.
Folks interested in making sure that a given platform's page table helpers
conform to expected generic MM semantics should enable the above config
which will just trigger this test during boot. Any non conformity here
will be reported as an warning which would need to be fixed. This test
will help catch any changes to the agreed upon semantics expected from
generic MM and enable platforms to accommodate it thereafter.
[anshuman.khandual@arm.com: v17]
Link: http://lkml.kernel.org/r/1587436495-22033-3-git-send-email-anshuman.khandual@arm.com
[anshuman.khandual@arm.com: v18]
Link: http://lkml.kernel.org/r/1588564865-31160-3-git-send-email-anshuman.khandual@arm.com
Suggested-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Qian Cai <cai@lca.pw>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> [s390]
Tested-by: Christophe Leroy <christophe.leroy@c-s.fr> [ppc32]
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Link: http://lkml.kernel.org/r/1583919272-24178-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "mm/debug: Add tests validating architecture page table
helpers", v18.
This adds a test validation for architecture exported page table helpers.
Patch adds basic transformation tests at various levels of the page table.
This test was originally suggested by Catalin during arm64 THP migration
RFC discussion earlier. Going forward it can include more specific tests
with respect to various generic MM functions like THP, HugeTLB etc and
platform specific tests.
https://lore.kernel.org/linux-mm/20190628102003.GA56463@arrakis.emea.arm.com/
This patch (of 2):
This just defines mm_p4d_folded() to check whether P4D page table level is
folded at runtime.
Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Link: http://lkml.kernel.org/r/1587436495-22033-2-git-send-email-anshuman.khandual@arm.com
Link: http://lkml.kernel.org/r/1588564865-31160-2-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There are no architectures that use include/asm-generic/5level-fixup.h
therefore it can be removed along with __ARCH_HAS_5LEVEL_HACK define and
the code it surrounds
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Brian Cain <bcain@codeaurora.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: James Morse <james.morse@arm.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Julien Thierry <julien.thierry.kdev@gmail.com>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: http://lkml.kernel.org/r/20200414153455.21744-15-rppt@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The unicore32 architecture has 2 level page tables and
asm-generic/pgtable-nopmd.h and explicit casts from pud_t to pgd_t for
page table folding.
Add p4d walk in the only place that actually unfolds the pud level and
remove __ARCH_USE_5LEVEL_HACK.
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Brian Cain <bcain@codeaurora.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: James Morse <james.morse@arm.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Julien Thierry <julien.thierry.kdev@gmail.com>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: http://lkml.kernel.org/r/20200414153455.21744-13-rppt@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The __pXd_offset() macros are identical to the pXd_index() macros and
there is no point to keep both of them. All architectures define and use
pXd_index() so let's keep only those to make mips consistent with the rest
of the kernel.
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Brian Cain <bcain@codeaurora.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: James Morse <james.morse@arm.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Julien Thierry <julien.thierry.kdev@gmail.com>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: http://lkml.kernel.org/r/20200414153455.21744-11-rppt@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- Convert from printk() to pr_*(),
- Add missing continuations,
- Use "%llx" to format u64,
- Join multiple prints in show_fault_oops() into a single print.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Brian Cain <bcain@codeaurora.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: James Morse <james.morse@arm.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Julien Thierry <julien.thierry.kdev@gmail.com>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: http://lkml.kernel.org/r/20200414153455.21744-10-rppt@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The hexagon architecture has 2 level page tables and as such most of the
page table folding is already implemented in asm-generic/pgtable-nopmd.h.
Fixup the only place in arch/hexagon to unfold the p4d level and remove
__ARCH_USE_5LEVEL_HACK.
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Brian Cain <bcain@codeaurora.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: James Morse <james.morse@arm.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Julien Thierry <julien.thierry.kdev@gmail.com>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: http://lkml.kernel.org/r/20200414153455.21744-5-rppt@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "mm: remove __ARCH_HAS_5LEVEL_HACK", v4.
These patches convert several architectures to use page table folding and
remove __ARCH_HAS_5LEVEL_HACK along with
include/asm-generic/5level-fixup.h and
include/asm-generic/pgtable-nop4d-hack.h. With that we'll have a single
and consistent way of dealing with page table folding instead of a mix of
three existing options.
The changes are mostly about mechanical replacement of pgd accessors with
p4d ones and the addition of higher levels to page table traversals.
This patch (of 14):
h8300 is a nommu architecture and does not require fixup for upper layers
of the page tables because it is already handled by the generic nommu
implementation.
Remove definition of __ARCH_USE_5LEVEL_HACK in
arch/h8300/include/asm/pgtable.h
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Brian Cain <bcain@codeaurora.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: James Morse <james.morse@arm.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Julien Thierry <julien.thierry.kdev@gmail.com>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com> [openrisc]
Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Joerg Roedel <joro@8bytes.org>
Link: http://lkml.kernel.org/r/20200414153455.21744-1-rppt@kernel.org
Link: http://lkml.kernel.org/r/20200414153455.21744-2-rppt@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This check was added by commit 82f71ae4a2 ("mm: catch memory
commitment underflow") in 2014 to have a safety check for issues which
have been fixed. And there has been few report caught by it, as
described in its commit log:
: This shouldn't happen any more - the previous two patches fixed
: the committed_as underflow issues.
But it was really found by Qian Cai when he used the LTP memory stress
suite to test a RFC patchset, which tries to improve scalability of
per-cpu counter 'vm_committed_as', by chosing a bigger 'batch' number for
loose overcommit policies (OVERCOMMIT_ALWAYS and OVERCOMMIT_GUESS), while
keeping current number for OVERCOMMIT_NEVER.
With that patchset, when system firstly uses a loose policy, the
'vm_committed_as' count could be a big negative value, as its big 'batch'
number allows a big deviation, then when the policy is changed to
OVERCOMMIT_NEVER, the 'batch' will be decreased to a much smaller value,
thus hits this WARN check.
To mitigate this, one proposed solution is to queue work on all online
CPUs to do a local sync for 'vm_committed_as' when changing policy to
OVERCOMMIT_NEVER, plus some global syncing to garante the case won't be
hit.
But this solution is costy and slow, given this check hasn't shown real
trouble or benefit, simply drop it from one hot path of MM. And perf
stats does show some tiny saving for removing it.
Reported-by: Qian Cai <cai@lca.pw>
Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Qian Cai <cai@lca.pw>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Andi Kleen <andi.kleen@intel.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Kees Cook <keescook@chromium.org>
Link: http://lkml.kernel.org/r/20200603094804.GB89848@shbuild999.sh.intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch adds kcov_remote_start/stop() callbacks around the urb
complete() callback that is executed in softirq context when dummy_hcd is
in use. As the result, kcov can be used to collect coverage from those
callbacks, which is used to facilitate coverage-guided fuzzing with
syzkaller.
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Marco Elver <elver@google.com>
Link: http://lkml.kernel.org/r/4520671eeb604adbc2432c248b0c07fbaa5519ef.1585233617.git.andreyknvl@google.com
Link: http://lkml.kernel.org/r/2821d497ac1cdc0efb5e00df30271e4a67fc8009.1584655448.git.andreyknvl@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This change extends kcov remote coverage support to allow collecting
coverage from soft interrupts in addition to kernel background threads.
To collect coverage from code that is executed in softirq context, a part
of that code has to be annotated with kcov_remote_start/stop() in a
similar way as how it is done for global kernel background threads. Then
the handle used for the annotations has to be passed to the
KCOV_REMOTE_ENABLE ioctl.
Internally this patch adjusts the __sanitizer_cov_trace_pc() compiler
inserted callback to not bail out when called from softirq context.
kcov_remote_start/stop() are updated to save/restore the current per task
kcov state in a per-cpu area (in case the softirq came when the kernel was
already collecting coverage in task context). Coverage from softirqs is
collected into pre-allocated per-cpu areas, whose size is controlled by
the new CONFIG_KCOV_IRQ_AREA_SIZE.
[andreyknvl@google.com: turn current->kcov_softirq into unsigned int to fix objtool warning]
Link: http://lkml.kernel.org/r/841c778aa3849c5cb8c3761f56b87ce653a88671.1585233617.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Marco Elver <elver@google.com>
Link: http://lkml.kernel.org/r/469bd385c431d050bc38a593296eff4baae50666.1584655448.git.andreyknvl@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently kcov_remote_start() and kcov_remote_stop() check t->kcov to find
out whether the coverage is already being collected by the current task.
Use t->kcov_mode for that instead. This doesn't change the overall
behavior in any way, but serves as a preparation for the following softirq
coverage collection support patch.
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Alexander Potapenko <glider@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Marco Elver <elver@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Link: http://lkml.kernel.org/r/f70377945d1d8e6e4916cbce871a12303d6186b4.1585233617.git.andreyknvl@google.com
Link: http://lkml.kernel.org/r/ee1a1dec43059da5d7664c85c1addc89c4cd58de.1584655448.git.andreyknvl@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If vmalloc() fails in kcov_remote_start() we'll access remote->kcov
without holding kcov_remote_lock, so remote might potentially be freed at
that point. Cache kcov pointer in a local variable.
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Alexander Potapenko <glider@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Marco Elver <elver@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Link: http://lkml.kernel.org/r/9d9134359725a965627b7e8f2652069f86f1d1fa.1585233617.git.andreyknvl@google.com
Link: http://lkml.kernel.org/r/de0d3d30ff90776a2a509cc34c7c1c7521bda125.1584655448.git.andreyknvl@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
