Commit Graph

386 Commits

Author SHA1 Message Date
Thomas Gleixner 457c899653 treewide: Add SPDX license identifier for missed files
Add SPDX license identifiers to all files which:

 - Have no license information of any form

 - Have EXPORT_.*_SYMBOL_GPL inside which was used in the
   initial scan/conversion to ignore the file

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 10:50:45 +02:00
Ingo Molnar 00f5764dbb Merge branch 'linus' into x86/urgent, to pick up dependent changes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-05-16 09:04:48 +02:00
David Hildenbrand ac5c942645 mm/memory_hotplug: make __remove_pages() and arch_remove_memory() never fail
All callers of arch_remove_memory() ignore errors.  And we should really
try to remove any errors from the memory removal path.  No more errors are
reported from __remove_pages().  BUG() in s390x code in case
arch_remove_memory() is triggered.  We may implement that properly later.
WARN in case powerpc code failed to remove the section mapping, which is
better than ignoring the error completely right now.

Link: http://lkml.kernel.org/r/20190409100148.24703-5-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
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: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Oscar Salvador <osalvador@suse.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Stefan Agner <stefan@agner.ch>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Arun KS <arunks@codeaurora.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Rob Herring <robh@kernel.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Qian Cai <cai@lca.pw>
Cc: Mathieu Malaterre <malat@debian.org>
Cc: Andrew Banman <andrew.banman@hpe.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Mike Travis <mike.travis@hpe.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 09:47:50 -07:00
Michal Hocko 940519f0c8 mm, memory_hotplug: provide a more generic restrictions for memory hotplug
arch_add_memory, __add_pages take a want_memblock which controls whether
the newly added memory should get the sysfs memblock user API (e.g.
ZONE_DEVICE users do not want/need this interface).  Some callers even
want to control where do we allocate the memmap from by configuring
altmap.

Add a more generic hotplug context for arch_add_memory and __add_pages.
struct mhp_restrictions contains flags which contains additional features
to be enabled by the memory hotplug (MHP_MEMBLOCK_API currently) and
altmap for alternative memmap allocator.

This patch shouldn't introduce any functional change.

[akpm@linux-foundation.org: build fix]
Link: http://lkml.kernel.org/r/20190408082633.2864-3-osalvador@suse.de
Signed-off-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Oscar Salvador <osalvador@suse.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 09:47:49 -07:00
Brijesh Singh eccd906484 x86/mm: Do not use set_{pud, pmd}_safe() when splitting a large page
The commit

  0a9fe8ca84 ("x86/mm: Validate kernel_physical_mapping_init() PTE population")

triggers this warning in SEV guests:

  WARNING: CPU: 0 PID: 0 at arch/x86/include/asm/pgalloc.h:87 phys_pmd_init+0x30d/0x386
  Call Trace:
   kernel_physical_mapping_init+0xce/0x259
   early_set_memory_enc_dec+0x10f/0x160
   kvm_smp_prepare_boot_cpu+0x71/0x9d
   start_kernel+0x1c9/0x50b
   secondary_startup_64+0xa4/0xb0

A SEV guest calls kernel_physical_mapping_init() to clear the encryption
mask from an existing mapping. While doing so, it also splits large
pages into smaller.

To split a page, kernel_physical_mapping_init() allocates a new page and
updates the existing entry. The set_{pud,pmd}_safe() helpers trigger a
warning when updating an entry with a page in the present state.

Add a new kernel_physical_mapping_change() helper which uses the
non-safe variants of set_{pmd,pud,p4d}() and {pmd,pud,p4d}_populate()
routines when updating the entry.

Since kernel_physical_mapping_change() may replace an existing
entry with a new entry, the caller is responsible to flush
the TLB at the end. Change early_set_memory_enc_dec() to use
kernel_physical_mapping_change() when it wants to clear the memory
encryption mask from the page table entry.

 [ bp:
   - massage commit message.
   - flesh out comment according to dhansen's request.
   - align function arguments at opening brace. ]

Fixes: 0a9fe8ca84 ("x86/mm: Validate kernel_physical_mapping_init() PTE population")
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Dave Hansen <dave.hansen@intel.com>
Acked-by:  Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas Lendacky <Thomas.Lendacky@amd.com>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20190417154102.22613-1-brijesh.singh@amd.com
2019-05-08 19:08:35 +02:00
Oscar Salvador 2c2a5af6fe mm, memory_hotplug: add nid parameter to arch_remove_memory
Patch series "Do not touch pages in hot-remove path", v2.

This patchset aims for two things:

 1) A better definition about offline and hot-remove stage
 2) Solving bugs where we can access non-initialized pages
    during hot-remove operations [2] [3].

This is achieved by moving all page/zone handling to the offline
stage, so we do not need to access pages when hot-removing memory.

[1] https://patchwork.kernel.org/cover/10691415/
[2] https://patchwork.kernel.org/patch/10547445/
[3] https://www.spinics.net/lists/linux-mm/msg161316.html

This patch (of 5):

This is a preparation for the following-up patches.  The idea of passing
the nid is that it will allow us to get rid of the zone parameter
afterwards.

Link: http://lkml.kernel.org/r/20181127162005.15833-2-osalvador@suse.de
Signed-off-by: Oscar Salvador <osalvador@suse.de>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>

Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-12-28 12:11:49 -08:00
Dan Williams ba6f508d0e x86/mm: Drop usage of __flush_tlb_all() in kernel_physical_mapping_init()
Commit:

  f77084d963 "x86/mm/pat: Disable preemption around __flush_tlb_all()"

addressed a case where __flush_tlb_all() is called without preemption
being disabled. It also left a warning to catch other cases where
preemption is not disabled.

That warning triggers for the memory hotplug path which is also used for
persistent memory enabling:

 WARNING: CPU: 35 PID: 911 at ./arch/x86/include/asm/tlbflush.h:460
 RIP: 0010:__flush_tlb_all+0x1b/0x3a
 [..]
 Call Trace:
  phys_pud_init+0x29c/0x2bb
  kernel_physical_mapping_init+0xfc/0x219
  init_memory_mapping+0x1a5/0x3b0
  arch_add_memory+0x2c/0x50
  devm_memremap_pages+0x3aa/0x610
  pmem_attach_disk+0x585/0x700 [nd_pmem]

Andy wondered why a path that can sleep was using __flush_tlb_all() [1]
and Dave confirmed the expectation for TLB flush is for modifying /
invalidating existing PTE entries, but not initial population [2]. Drop
the usage of __flush_tlb_all() in phys_{p4d,pud,pmd}_init() on the
expectation that this path is only ever populating empty entries for the
linear map. Note, at linear map teardown time there is a call to the
all-cpu flush_tlb_all() to invalidate the removed mappings.

[1]: https://lkml.kernel.org/r/9DFD717D-857D-493D-A606-B635D72BAC21@amacapital.net
[2]: https://lkml.kernel.org/r/749919a4-cdb1-48a3-adb4-adb81a5fa0b5@intel.com

[ mingo: Minor readability edits. ]

Suggested-by: Dave Hansen <dave.hansen@linux.intel.com>
Reported-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: <stable@vger.kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dave.hansen@intel.com
Fixes: f77084d963 ("x86/mm/pat: Disable preemption around __flush_tlb_all()")
Link: http://lkml.kernel.org/r/154395944713.32119.15611079023837132638.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-12-05 09:03:07 +01:00
Dan Williams 0a9fe8ca84 x86/mm: Validate kernel_physical_mapping_init() PTE population
The usage of __flush_tlb_all() in the kernel_physical_mapping_init()
path is not necessary. In general flushing the TLB is not required when
updating an entry from the !present state. However, to give confidence
in the future removal of TLB flushing in this path, use the new
set_pte_safe() family of helpers to assert that the !present assumption
is true in this path.

[ mingo: Minor readability edits. ]

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Suggested-by: Dave Hansen <dave.hansen@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/154395944177.32119.8524957429632012270.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-12-05 09:03:06 +01:00
Mike Rapoport 57c8a661d9 mm: remove include/linux/bootmem.h
Move remaining definitions and declarations from include/linux/bootmem.h
into include/linux/memblock.h and remove the redundant header.

The includes were replaced with the semantic patch below and then
semi-automated removal of duplicated '#include <linux/memblock.h>

@@
@@
- #include <linux/bootmem.h>
+ #include <linux/memblock.h>

[sfr@canb.auug.org.au: dma-direct: fix up for the removal of linux/bootmem.h]
  Link: http://lkml.kernel.org/r/20181002185342.133d1680@canb.auug.org.au
[sfr@canb.auug.org.au: powerpc: fix up for removal of linux/bootmem.h]
  Link: http://lkml.kernel.org/r/20181005161406.73ef8727@canb.auug.org.au
[sfr@canb.auug.org.au: x86/kaslr, ACPI/NUMA: fix for linux/bootmem.h removal]
  Link: http://lkml.kernel.org/r/20181008190341.5e396491@canb.auug.org.au
Link: http://lkml.kernel.org/r/1536927045-23536-30-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Serge Semin <fancer.lancer@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-10-31 08:54:16 -07:00
Mike Rapoport c6ffc5ca8f memblock: rename free_all_bootmem to memblock_free_all
The conversion is done using

sed -i 's@free_all_bootmem@memblock_free_all@' \
    $(git grep -l free_all_bootmem)

Link: http://lkml.kernel.org/r/1536927045-23536-26-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Serge Semin <fancer.lancer@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-10-31 08:54:16 -07:00
Mike Rapoport 15c3c114ed memblock: replace alloc_bootmem_pages with memblock_alloc
The alloc_bootmem_pages() function allocates PAGE_SIZE aligned memory.
memblock_alloc() with alignment set to PAGE_SIZE does exactly the same
thing.

The conversion is done using the following semantic patch:

@@
expression e;
@@
- alloc_bootmem_pages(e)
+ memblock_alloc(e, PAGE_SIZE)

Link: http://lkml.kernel.org/r/1536927045-23536-20-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Serge Semin <fancer.lancer@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-10-31 08:54:15 -07:00
Thomas Gleixner 315706049c Merge branch 'x86/pti-urgent' into x86/pti
Integrate the PTI Global bit fixes which conflict with the 32bit PTI
support.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2018-08-06 20:56:34 +02:00
Dave Hansen 6ea2738e0c x86/mm/init: Add helper for freeing kernel image pages
When chunks of the kernel image are freed, free_init_pages() is used
directly.  Consolidate the three sites that do this.  Also update the
string to give an incrementally better description of that memory versus
what was there before.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: keescook@google.com
Cc: aarcange@redhat.com
Cc: jgross@suse.com
Cc: jpoimboe@redhat.com
Cc: gregkh@linuxfoundation.org
Cc: peterz@infradead.org
Cc: hughd@google.com
Cc: torvalds@linux-foundation.org
Cc: bp@alien8.de
Cc: luto@kernel.org
Cc: ak@linux.intel.com
Cc: Kees Cook <keescook@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Link: https://lkml.kernel.org/r/20180802225829.FE0E32EA@viggo.jf.intel.com
2018-08-05 22:21:03 +02:00
Dave Hansen 9f515cdb41 x86/mm/init: Pass unconverted symbol addresses to free_init_pages()
The x86 code has several places where it frees parts of kernel image:

 1. Unused SMP alternative
 2. __init code
 3. The hole between text and rodata
 4. The hole between rodata and data

We call free_init_pages() to do this.  Strangely, we convert the symbol
addresses to kernel direct map addresses in some cases (#3, #4) but not
others (#1, #2).

The virt_to_page() and the other code in free_reserved_area() now works
fine for for symbol addresses on x86, so don't bother converting the
addresses to direct map addresses before freeing them.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: keescook@google.com
Cc: aarcange@redhat.com
Cc: jgross@suse.com
Cc: jpoimboe@redhat.com
Cc: gregkh@linuxfoundation.org
Cc: peterz@infradead.org
Cc: hughd@google.com
Cc: torvalds@linux-foundation.org
Cc: bp@alien8.de
Cc: luto@kernel.org
Cc: ak@linux.intel.com
Cc: Kees Cook <keescook@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Link: https://lkml.kernel.org/r/20180802225828.89B2D0E2@viggo.jf.intel.com
2018-08-05 22:21:02 +02:00
Joerg Roedel b976690f5d x86/mm/pti: Introduce pti_finalize()
Introduce a new function to finalize the kernel mappings for the userspace
page-table after all ro/nx protections have been applied to the kernel
mappings.

Also move the call to pti_clone_kernel_text() to that function so that it
will run on 32 bit kernels too.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Pavel Machek <pavel@ucw.cz>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: linux-mm@kvack.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Waiman Long <llong@redhat.com>
Cc: "David H . Gutteridge" <dhgutteridge@sympatico.ca>
Cc: joro@8bytes.org
Link: https://lkml.kernel.org/r/1531906876-13451-30-git-send-email-joro@8bytes.org
2018-07-20 01:11:45 +02:00
Thomas Gleixner 7731b8bc94 Merge branch 'linus' into x86/urgent
Required to queue a dependent fix.
2018-06-22 21:20:35 +02:00
mike.travis@hpe.com f642fb5864 x86/platform/UV: Add adjustable set memory block size function
Add a new function to "adjust" the current fixed UV memory block size
of 2GB so it can be changed to a different physical boundary.  This is
out of necessity so arch dependent code can accommodate specific BIOS
requirements which can align these new PMEM modules at less than the
default boundaries.

A "set order" type of function was used to insure that the memory block
size will be a power of two value without requiring a validity check.
64GB was chosen as the upper limit for memory block size values to
accommodate upcoming 4PB systems which have 6 more bits of physical
address space (46 becoming 52).

Signed-off-by: Mike Travis <mike.travis@hpe.com>
Reviewed-by: Andrew Banman <andrew.banman@hpe.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dimitri Sivanich <dimitri.sivanich@hpe.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russ Anderson <russ.anderson@hpe.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dan.j.williams@intel.com
Cc: jgross@suse.com
Cc: kirill.shutemov@linux.intel.com
Cc: mhocko@suse.com
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/lkml/20180524201711.609546602@stormcage.americas.sgi.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-06-21 16:14:45 +02:00
Stefan Agner d7dc899abe treewide: use PHYS_ADDR_MAX to avoid type casting ULLONG_MAX
With PHYS_ADDR_MAX there is now a type safe variant for all bits set.
Make use of it.

Patch created using a semantic patch as follows:

// <smpl>
@@
typedef phys_addr_t;
@@
-(phys_addr_t)ULLONG_MAX
+PHYS_ADDR_MAX
// </smpl>

Link: http://lkml.kernel.org/r/20180419214204.19322-1-stefan@agner.ch
Signed-off-by: Stefan Agner <stefan@agner.ch>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>	[arm64]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-06-15 07:55:25 +09:00
Kirill A. Shutemov ed7588d5dc x86/mm: Stop pretending pgtable_l5_enabled is a variable
pgtable_l5_enabled is defined using cpu_feature_enabled() but we refer
to it as a variable. This is misleading.

Make pgtable_l5_enabled() a function.

We cannot literally define it as a function due to circular dependencies
between header files. Function-alike macros is close enough.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180518103528.59260-4-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-05-19 11:56:57 +02:00
Linus Torvalds 6b0a02e86c Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 pti updates from Thomas Gleixner:
 "Another series of PTI related changes:

   - Remove the manual stack switch for user entries from the idtentry
     code. This debloats entry by 5k+ bytes of text.

   - Use the proper types for the asm/bootparam.h defines to prevent
     user space compile errors.

   - Use PAGE_GLOBAL for !PCID systems to gain back performance

   - Prevent setting of huge PUD/PMD entries when the entries are not
     leaf entries otherwise the entries to which the PUD/PMD points to
     and are populated get lost"

* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/pgtable: Don't set huge PUD/PMD on non-leaf entries
  x86/pti: Leave kernel text global for !PCID
  x86/pti: Never implicitly clear _PAGE_GLOBAL for kernel image
  x86/pti: Enable global pages for shared areas
  x86/mm: Do not forbid _PAGE_RW before init for __ro_after_init
  x86/mm: Comment _PAGE_GLOBAL mystery
  x86/mm: Remove extra filtering in pageattr code
  x86/mm: Do not auto-massage page protections
  x86/espfix: Document use of _PAGE_GLOBAL
  x86/mm: Introduce "default" kernel PTE mask
  x86/mm: Undo double _PAGE_PSE clearing
  x86/mm: Factor out pageattr _PAGE_GLOBAL setting
  x86/entry/64: Drop idtentry's manual stack switch for user entries
  x86/uapi: Fix asm/bootparam.h userspace compilation errors
2018-04-15 13:35:29 -07:00
Dave Hansen 8c06c7740d x86/pti: Leave kernel text global for !PCID
Global pages are bad for hardening because they potentially let an
exploit read the kernel image via a Meltdown-style attack which
makes it easier to find gadgets.

But, global pages are good for performance because they reduce TLB
misses when making user/kernel transitions, especially when PCIDs
are not available, such as on older hardware, or where a hypervisor
has disabled them for some reason.

This patch implements a basic, sane policy: If you have PCIDs, you
only map a minimal amount of kernel text global.  If you do not have
PCIDs, you map all kernel text global.

This policy effectively makes PCIDs something that not only adds
performance but a little bit of hardening as well.

I ran a simple "lseek" microbenchmark[1] to test the benefit on
a modern Atom microserver.  Most of the benefit comes from applying
the series before this patch ("entry only"), but there is still a
signifiant benefit from this patch.

  No Global Lines (baseline  ): 6077741 lseeks/sec
  88 Global Lines (entry only): 7528609 lseeks/sec (+23.9%)
  94 Global Lines (this patch): 8433111 lseeks/sec (+38.8%)

[1.] https://github.com/antonblanchard/will-it-scale/blob/master/tests/lseek1.c

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kees Cook <keescook@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nadav Amit <namit@vmware.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180406205518.E3D989EB@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-04-12 09:06:00 +02:00
Pavel Tatashin 6f84f8d158 xen, mm: allow deferred page initialization for xen pv domains
Juergen Gross noticed that commit f7f99100d8 ("mm: stop zeroing memory
during allocation in vmemmap") broke XEN PV domains when deferred struct
page initialization is enabled.

This is because the xen's PagePinned() flag is getting erased from
struct pages when they are initialized later in boot.

Juergen fixed this problem by disabling deferred pages on xen pv
domains.  It is desirable, however, to have this feature available as it
reduces boot time.  This fix re-enables the feature for pv-dmains, and
fixes the problem the following way:

The fix is to delay setting PagePinned flag until struct pages for all
allocated memory are initialized, i.e.  until after free_all_bootmem().

A new x86_init.hyper op init_after_bootmem() is called to let xen know
that boot allocator is done, and hence struct pages for all the
allocated memory are now initialized.  If deferred page initialization
is enabled, the rest of struct pages are going to be initialized later
in boot once page_alloc_init_late() is called.

xen_after_bootmem() walks page table's pages and marks them pinned.

Link: http://lkml.kernel.org/r/20180226160112.24724-2-pasha.tatashin@oracle.com
Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Juergen Gross <jgross@suse.com>
Tested-by: Juergen Gross <jgross@suse.com>
Cc: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Pavel Tatashin <pasha.tatashin@oracle.com>
Cc: Alok Kataria <akataria@vmware.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Mathias Krause <minipli@googlemail.com>
Cc: Jinbum Park <jinb.park7@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Jia Zhang <zhang.jia@linux.alibaba.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:38 -07:00
Dave Hansen 8a57f4849f x86/mm: Introduce "default" kernel PTE mask
The __PAGE_KERNEL_* page permissions are "raw".  They contain bits
that may or may not be supported on the current processor.  They need
to be filtered by a mask (currently __supported_pte_mask) to turn them
into a value that we can actually set in a PTE.

These __PAGE_KERNEL_* values all contain _PAGE_GLOBAL.  But, with PTI,
we want to be able to support _PAGE_GLOBAL (have the bit set in
__supported_pte_mask) but not have it appear in any of these masks by
default.

This patch creates a new mask, __default_kernel_pte_mask, and applies
it when creating all of the PAGE_KERNEL_* masks.  This makes
PAGE_KERNEL_* safe to use anywhere (they only contain supported bits).
It also ensures that PAGE_KERNEL_* contains _PAGE_GLOBAL on PTI=n
kernels but clears _PAGE_GLOBAL when PTI=y.

We also make __default_kernel_pte_mask a non-GPL exported symbol
because there are plenty of driver-available interfaces that take
PAGE_KERNEL_* permissions.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kees Cook <keescook@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nadav Amit <namit@vmware.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180406205506.030DB6B6@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-04-09 18:27:32 +02:00
Pavel Tatashin 078eb6aa50 x86/mm/memory_hotplug: determine block size based on the end of boot memory
Memory sections are combined into "memory block" chunks.  These chunks
are the units upon which memory can be added and removed.

On x86, the new memory may be added after the end of the boot memory,
therefore, if block size does not align with end of boot memory, memory
hot-plugging/hot-removing can be broken.

Memory sections are combined into "memory block" chunks.  These chunks
are the units upon which memory can be added and removed.

On x86 the new memory may be added after the end of the boot memory,
therefore, if block size does not align with end of boot memory, memory
hotplugging/hotremoving can be broken.

Currently, whenever machine is booted with more than 64G the block size
is unconditionally increased to 2G from the base 128M.  This is done in
order to reduce number of memory device files in sysfs:

	/sys/devices/system/memory/memoryXXX

We must use the largest allowed block size that aligns to the next
address to be able to hotplug the next block of memory.

So, when memory is larger or equal to 64G, we check the end address and
find the largest block size that is still power of two but smaller or
equal to 2G.

Before, the fix:
Run qemu with:
-m 64G,slots=2,maxmem=66G -object memory-backend-ram,id=mem1,size=2G

(qemu) device_add pc-dimm,id=dimm1,memdev=mem1
Block size [0x80000000] unaligned hotplug range: start 0x1040000000,
							size 0x80000000
acpi PNP0C80:00: add_memory failed
acpi PNP0C80:00: acpi_memory_enable_device() error
acpi PNP0C80:00: Enumeration failure

With the fix memory is added successfully as the block size is set to
1G, and therefore aligns with start address 0x1040000000.

[pasha.tatashin@oracle.com: v4]
  Link: http://lkml.kernel.org/r/20180215165920.8570-3-pasha.tatashin@oracle.com
Link: http://lkml.kernel.org/r/20180213193159.14606-3-pasha.tatashin@oracle.com
Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Steven Sistare <steven.sistare@oracle.com>
Cc: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Bharata B Rao <bharata@linux.vnet.ibm.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Baoquan He <bhe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-05 21:36:25 -07:00
Ingo Molnar 0bc91d4ba7 Linux 4.16-rc7
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Merge tag 'v4.16-rc7' into x86/mm, to fix up conflict

 Conflicts:
	arch/x86/mm/init_64.c

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-27 08:43:39 +02:00
Dan Williams a7e6c7015b x86, memremap: fix altmap accounting at free
Commit 24b6d41643 "mm: pass the vmem_altmap to vmemmap_free" converted
the vmemmap_free() path to pass the altmap argument all the way through
the call chain rather than looking it up based on the page.
Unfortunately that ends up over freeing altmap allocated pages in some
cases since free_pagetable() is used to free both memmap space and pte
space, where only the memmap stored in huge pages uses altmap
allocations.

Given that altmap allocations for memmap space are special cased in
vmemmap_populate_hugepages() add a symmetric / special case
free_hugepage_table() to handle altmap freeing, and cleanup the unneeded
passing of altmap to leaf functions that do not require it.

Without this change the sanity check accounting in
devm_memremap_pages_release() will throw a warning with the following
signature.

 nd_pmem pfn10.1: devm_memremap_pages_release: failed to free all reserved pages
 WARNING: CPU: 44 PID: 3539 at kernel/memremap.c:310 devm_memremap_pages_release+0x1c7/0x220
 CPU: 44 PID: 3539 Comm: ndctl Tainted: G             L   4.16.0-rc1-linux-stable #7
 RIP: 0010:devm_memremap_pages_release+0x1c7/0x220
 [..]
 Call Trace:
  release_nodes+0x225/0x270
  device_release_driver_internal+0x15d/0x210
  bus_remove_device+0xe2/0x160
  device_del+0x130/0x310
  ? klist_release+0x56/0x100
  ? nd_region_notify+0xc0/0xc0 [libnvdimm]
  device_unregister+0x16/0x60

This was missed in testing since not all configurations will trigger
this warning.

Fixes: 24b6d41643 ("mm: pass the vmem_altmap to vmemmap_free")
Reported-by: Jane Chu <jane.chu@oracle.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-03-14 14:46:23 -07:00
Ingo Molnar 3f7df3efeb Linux 4.16-rc3
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Merge tag 'v4.16-rc3' into x86/mm, to pick up fixes

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-26 08:41:15 +01:00
Kirill A. Shutemov 91f606a8fa x86/mm: Replace compile-time checks for 5-level paging with runtime-time checks
This patch converts the of CONFIG_X86_5LEVEL check to runtime checks for
p4d folding.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180214182542.69302-9-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-16 10:48:49 +01:00
Linus Torvalds e525de3ab0 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Ingo Molnar:
 "Misc fixes all across the map:

   - /proc/kcore vsyscall related fixes
   - LTO fix
   - build warning fix
   - CPU hotplug fix
   - Kconfig NR_CPUS cleanups
   - cpu_has() cleanups/robustification
   - .gitignore fix
   - memory-failure unmapping fix
   - UV platform fix"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm, mm/hwpoison: Don't unconditionally unmap kernel 1:1 pages
  x86/error_inject: Make just_return_func() globally visible
  x86/platform/UV: Fix GAM Range Table entries less than 1GB
  x86/build: Add arch/x86/tools/insn_decoder_test to .gitignore
  x86/smpboot: Fix uncore_pci_remove() indexing bug when hot-removing a physical CPU
  x86/mm/kcore: Add vsyscall page to /proc/kcore conditionally
  vfs/proc/kcore, x86/mm/kcore: Fix SMAP fault when dumping vsyscall user page
  x86/Kconfig: Further simplify the NR_CPUS config
  x86/Kconfig: Simplify NR_CPUS config
  x86/MCE: Fix build warning introduced by "x86: do not use print_symbol()"
  x86/cpufeature: Update _static_cpu_has() to use all named variables
  x86/cpufeature: Reindent _static_cpu_has()
2018-02-14 17:31:51 -08:00
Linus Torvalds d4667ca142 Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 PTI and Spectre related fixes and updates from Ingo Molnar:
 "Here's the latest set of Spectre and PTI related fixes and updates:

  Spectre:
   - Add entry code register clearing to reduce the Spectre attack
     surface
   - Update the Spectre microcode blacklist
   - Inline the KVM Spectre helpers to get close to v4.14 performance
     again.
   - Fix indirect_branch_prediction_barrier()
   - Fix/improve Spectre related kernel messages
   - Fix array_index_nospec_mask() asm constraint
   - KVM: fix two MSR handling bugs

  PTI:
   - Fix a paranoid entry PTI CR3 handling bug
   - Fix comments

  objtool:
   - Fix paranoid_entry() frame pointer warning
   - Annotate WARN()-related UD2 as reachable
   - Various fixes
   - Add Add Peter Zijlstra as objtool co-maintainer

  Misc:
   - Various x86 entry code self-test fixes
   - Improve/simplify entry code stack frame generation and handling
     after recent heavy-handed PTI and Spectre changes. (There's two
     more WIP improvements expected here.)
   - Type fix for cache entries

  There's also some low risk non-fix changes I've included in this
  branch to reduce backporting conflicts:

   - rename a confusing x86_cpu field name
   - de-obfuscate the naming of single-TLB flushing primitives"

* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (41 commits)
  x86/entry/64: Fix CR3 restore in paranoid_exit()
  x86/cpu: Change type of x86_cache_size variable to unsigned int
  x86/spectre: Fix an error message
  x86/cpu: Rename cpu_data.x86_mask to cpu_data.x86_stepping
  selftests/x86/mpx: Fix incorrect bounds with old _sigfault
  x86/mm: Rename flush_tlb_single() and flush_tlb_one() to __flush_tlb_one_[user|kernel]()
  x86/speculation: Add <asm/msr-index.h> dependency
  nospec: Move array_index_nospec() parameter checking into separate macro
  x86/speculation: Fix up array_index_nospec_mask() asm constraint
  x86/debug: Use UD2 for WARN()
  x86/debug, objtool: Annotate WARN()-related UD2 as reachable
  objtool: Fix segfault in ignore_unreachable_insn()
  selftests/x86: Disable tests requiring 32-bit support on pure 64-bit systems
  selftests/x86: Do not rely on "int $0x80" in single_step_syscall.c
  selftests/x86: Do not rely on "int $0x80" in test_mremap_vdso.c
  selftests/x86: Fix build bug caused by the 5lvl test which has been moved to the VM directory
  selftests/x86/pkeys: Remove unused functions
  selftests/x86: Clean up and document sscanf() usage
  selftests/x86: Fix vDSO selftest segfault for vsyscall=none
  x86/entry/64: Remove the unused 'icebp' macro
  ...
2018-02-14 17:02:15 -08:00
Andy Lutomirski 1299ef1d88 x86/mm: Rename flush_tlb_single() and flush_tlb_one() to __flush_tlb_one_[user|kernel]()
flush_tlb_single() and flush_tlb_one() sound almost identical, but
they really mean "flush one user translation" and "flush one kernel
translation".  Rename them to flush_tlb_one_user() and
flush_tlb_one_kernel() to make the semantics more obvious.

[ I was looking at some PTI-related code, and the flush-one-address code
  is unnecessarily hard to understand because the names of the helpers are
  uninformative.  This came up during PTI review, but no one got around to
  doing it. ]

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kees Cook <keescook@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Linux-MM <linux-mm@kvack.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Link: http://lkml.kernel.org/r/3303b02e3c3d049dc5235d5651e0ae6d29a34354.1517414378.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-15 01:15:52 +01:00
Kirill A. Shutemov c65e774fb3 x86/mm: Make PGDIR_SHIFT and PTRS_PER_P4D variable
For boot-time switching between 4- and 5-level paging we need to be able
to fold p4d page table level at runtime. It requires variable
PGDIR_SHIFT and PTRS_PER_P4D.

The change doesn't affect the kernel image size much:

   text	   data	    bss	    dec	    hex	filename
8628091	4734304	1368064	14730459	 e0c4db	vmlinux.before
8628393	4734340	1368064	14730797	 e0c62d	vmlinux.after

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180214111656.88514-7-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-14 13:11:14 +01:00
Jia Zhang cd026ca286 x86/mm/kcore: Add vsyscall page to /proc/kcore conditionally
The vsyscall page should be visible only if vsyscall=emulate/native when dumping /proc/kcore.

Signed-off-by: Jia Zhang <zhang.jia@linux.alibaba.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: jolsa@redhat.com
Link: http://lkml.kernel.org/r/1518446694-21124-3-git-send-email-zhang.jia@linux.alibaba.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-13 09:15:59 +01:00
Jia Zhang 595dd46ebf vfs/proc/kcore, x86/mm/kcore: Fix SMAP fault when dumping vsyscall user page
Commit:

  df04abfd18 ("fs/proc/kcore.c: Add bounce buffer for ktext data")

... introduced a bounce buffer to work around CONFIG_HARDENED_USERCOPY=y.
However, accessing the vsyscall user page will cause an SMAP fault.

Replace memcpy() with copy_from_user() to fix this bug works, but adding
a common way to handle this sort of user page may be useful for future.

Currently, only vsyscall page requires KCORE_USER.

Signed-off-by: Jia Zhang <zhang.jia@linux.alibaba.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: jolsa@redhat.com
Link: http://lkml.kernel.org/r/1518446694-21124-2-git-send-email-zhang.jia@linux.alibaba.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-13 09:15:58 +01:00
Christoph Hellwig a8fc357b28 mm: split altmap memory map allocation from normal case
No functional changes, just untangling the call chain and document
why the altmap is passed around the hotplug code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-01-08 11:46:23 -08:00
Christoph Hellwig 24b6d41643 mm: pass the vmem_altmap to vmemmap_free
We can just pass this on instead of having to do a radix tree lookup
without proper locking a few levels into the callchain.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-01-08 11:46:23 -08:00
Christoph Hellwig da024512a1 mm: pass the vmem_altmap to arch_remove_memory and __remove_pages
We can just pass this on instead of having to do a radix tree lookup
without proper locking 2 levels into the callchain.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-01-08 11:46:23 -08:00
Christoph Hellwig 7b73d978a5 mm: pass the vmem_altmap to vmemmap_populate
We can just pass this on instead of having to do a radix tree lookup
without proper locking a few levels into the callchain.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-01-08 11:46:23 -08:00
Christoph Hellwig 24e6d5a59a mm: pass the vmem_altmap to arch_add_memory and __add_pages
We can just pass this on instead of having to do a radix tree lookup
without proper locking 2 levels into the callchain.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-01-08 11:46:23 -08:00
Christoph Hellwig 4dfeeaad63 mm: don't export arch_add_memory
Only x86_64 and sh export this symbol, and it is not used by any
modular code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-01-08 11:46:23 -08:00
Michal Hocko fcdaf842bd mm, sparse: do not swamp log with huge vmemmap allocation failures
While doing memory hotplug tests under heavy memory pressure we have
noticed too many page allocation failures when allocating vmemmap memmap
backed by huge page

  kworker/u3072:1: page allocation failure: order:9, mode:0x24084c0(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO)
  [...]
  Call Trace:
    dump_trace+0x59/0x310
    show_stack_log_lvl+0xea/0x170
    show_stack+0x21/0x40
    dump_stack+0x5c/0x7c
    warn_alloc_failed+0xe2/0x150
    __alloc_pages_nodemask+0x3ed/0xb20
    alloc_pages_current+0x7f/0x100
    vmemmap_alloc_block+0x79/0xb6
    __vmemmap_alloc_block_buf+0x136/0x145
    vmemmap_populate+0xd2/0x2b9
    sparse_mem_map_populate+0x23/0x30
    sparse_add_one_section+0x68/0x18e
    __add_pages+0x10a/0x1d0
    arch_add_memory+0x4a/0xc0
    add_memory_resource+0x89/0x160
    add_memory+0x6d/0xd0
    acpi_memory_device_add+0x181/0x251
    acpi_bus_attach+0xfd/0x19b
    acpi_bus_scan+0x59/0x69
    acpi_device_hotplug+0xd2/0x41f
    acpi_hotplug_work_fn+0x1a/0x23
    process_one_work+0x14e/0x410
    worker_thread+0x116/0x490
    kthread+0xbd/0xe0
    ret_from_fork+0x3f/0x70

and we do see many of those because essentially every allocation fails
for each memory section.  This is an excessive way to tell the user that
there is nothing to really worry about because we do have a fallback
mechanism to use base pages.  The only downside might be a performance
degradation due to TLB pressure.

This patch changes vmemmap_alloc_block() to use __GFP_NOWARN and warn
explicitly once on the first allocation failure.  This will reduce the
noise in the kernel log considerably, while we still have an indication
that a performance might be impacted.

[mhocko@kernel.org: forgot to git add the follow up fix]
  Link: http://lkml.kernel.org/r/20171107090635.c27thtse2lchjgvb@dhcp22.suse.cz
Link: http://lkml.kernel.org/r/20171106092228.31098-1-mhocko@kernel.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Michal Hocko <mhocko@suse.com>
Cc: Joe Perches <joe@perches.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Khalid Aziz <khalid.aziz@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15 18:21:07 -08:00
Pavel Tatashin 353b1e7b58 x86/mm: set fields in deferred pages
Without deferred struct page feature (CONFIG_DEFERRED_STRUCT_PAGE_INIT),
flags and other fields in "struct page"es are never changed prior to
first initializing struct pages by going through __init_single_page().

With deferred struct page feature enabled, however, we set fields in
register_page_bootmem_info that are subsequently clobbered right after
in free_all_bootmem:

        mem_init() {
                register_page_bootmem_info();
                free_all_bootmem();
                ...
        }

When register_page_bootmem_info() is called only non-deferred struct
pages are initialized.  But, this function goes through some reserved
pages which might be part of the deferred, and thus are not yet
initialized.

  mem_init
   register_page_bootmem_info
    register_page_bootmem_info_node
     get_page_bootmem
      .. setting fields here ..
      such as: page->freelist = (void *)type;

  free_all_bootmem()
   free_low_memory_core_early()
    for_each_reserved_mem_region()
     reserve_bootmem_region()
      init_reserved_page() <- Only if this is deferred reserved page
       __init_single_pfn()
        __init_single_page()
            memset(0) <-- Loose the set fields here

We end up with issue where, currently we do not observe problem as
memory is explicitly zeroed.  But, if flag asserts are changed we can
start hitting issues.

Also, because in this patch series we will stop zeroing struct page
memory during allocation, we must make sure that struct pages are
properly initialized prior to using them.

The deferred-reserved pages are initialized in free_all_bootmem().
Therefore, the fix is to switch the above calls.

Link: http://lkml.kernel.org/r/20171013173214.27300-3-pasha.tatashin@oracle.com
Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Reviewed-by: Steven Sistare <steven.sistare@oracle.com>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Reviewed-by: Bob Picco <bob.picco@oracle.com>
Tested-by: Bob Picco <bob.picco@oracle.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15 18:21:05 -08:00
Levin, Alexander (Sasha Levin) 75f296d93b kmemcheck: stop using GFP_NOTRACK and SLAB_NOTRACK
Convert all allocations that used a NOTRACK flag to stop using it.

Link: http://lkml.kernel.org/r/20171007030159.22241-3-alexander.levin@verizon.com
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tim Hansen <devtimhansen@gmail.com>
Cc: Vegard Nossum <vegardno@ifi.uio.no>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15 18:21:04 -08:00
Baoquan He 15670bfe19 x86/mm/64: Rename the register_page_bootmem_memmap() 'size' parameter to 'nr_pages'
register_page_bootmem_memmap()'s 3rd 'size' parameter is named
in a somewhat misleading fashion - rename it to 'nr_pages' which
makes the units of it much clearer.

Meanwhile rename the existing local variable 'nr_pages' to
'nr_pmd_pages', a more expressive name, to avoid conflict with
new function parameter 'nr_pages'.

(Also clean up the unnecessary parentheses in which get_order() is called.)

Signed-off-by: Baoquan He <bhe@redhat.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: akpm@linux-foundation.org
Link: http://lkml.kernel.org/r/1509154238-23250-1-git-send-email-bhe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-10-30 10:30:23 +01:00
Michal Hocko 3072e413e3 mm/memory_hotplug: introduce add_pages
There are new users of memory hotplug emerging.  Some of them require
different subset of arch_add_memory.  There are some which only require
allocation of struct pages without mapping those pages to the kernel
address space.  We currently have __add_pages for that purpose.  But this
is rather lowlevel and not very suitable for the code outside of the
memory hotplug.  E.g.  x86_64 wants to update max_pfn which should be done
by the caller.  Introduce add_pages() which should care about those
details if they are needed.  Each architecture should define its
implementation and select CONFIG_ARCH_HAS_ADD_PAGES.  All others use the
currently existing __add_pages.

Link: http://lkml.kernel.org/r/20170817000548.32038-7-jglisse@redhat.com
Signed-off-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Jérôme Glisse <jglisse@redhat.com>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Cc: Aneesh Kumar <aneesh.kumar@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Nellans <dnellans@nvidia.com>
Cc: Evgeny Baskakov <ebaskakov@nvidia.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Mark Hairgrove <mhairgrove@nvidia.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Sherry Cheung <SCheung@nvidia.com>
Cc: Subhash Gutti <sgutti@nvidia.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Bob Liu <liubo95@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-09-08 18:26:46 -07:00
Michal Hocko 3d79a728f9 mm, memory_hotplug: replace for_device by want_memblock in arch_add_memory
arch_add_memory gets for_device argument which then controls whether we
want to create memblocks for created memory sections.  Simplify the
logic by telling whether we want memblocks directly rather than going
through pointless negation.  This also makes the api easier to
understand because it is clear what we want rather than nothing telling
for_device which can mean anything.

This shouldn't introduce any functional change.

Link: http://lkml.kernel.org/r/20170515085827.16474-13-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Tested-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Daniel Kiper <daniel.kiper@oracle.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Joonsoo Kim <js1304@gmail.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Reza Arbab <arbab@linux.vnet.ibm.com>
Cc: Tobias Regnery <tobias.regnery@gmail.com>
Cc: Toshi Kani <toshi.kani@hpe.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-06 16:24:32 -07:00
Michal Hocko f1dd2cd13c mm, memory_hotplug: do not associate hotadded memory to zones until online
The current memory hotplug implementation relies on having all the
struct pages associate with a zone/node during the physical hotplug
phase (arch_add_memory->__add_pages->__add_section->__add_zone).  In the
vast majority of cases this means that they are added to ZONE_NORMAL.
This has been so since 9d99aaa31f ("[PATCH] x86_64: Support memory
hotadd without sparsemem") and it wasn't a big deal back then because
movable onlining didn't exist yet.

Much later memory hotplug wanted to (ab)use ZONE_MOVABLE for movable
onlining 511c2aba8f ("mm, memory-hotplug: dynamic configure movable
memory and portion memory") and then things got more complicated.
Rather than reconsidering the zone association which was no longer
needed (because the memory hotplug already depended on SPARSEMEM) a
convoluted semantic of zone shifting has been developed.  Only the
currently last memblock or the one adjacent to the zone_movable can be
onlined movable.  This essentially means that the online type changes as
the new memblocks are added.

Let's simulate memory hot online manually
  $ echo 0x100000000 > /sys/devices/system/memory/probe
  $ grep . /sys/devices/system/memory/memory32/valid_zones
  Normal Movable

  $ echo $((0x100000000+(128<<20))) > /sys/devices/system/memory/probe
  $ grep . /sys/devices/system/memory/memory3?/valid_zones
  /sys/devices/system/memory/memory32/valid_zones:Normal
  /sys/devices/system/memory/memory33/valid_zones:Normal Movable

  $ echo $((0x100000000+2*(128<<20))) > /sys/devices/system/memory/probe
  $ grep . /sys/devices/system/memory/memory3?/valid_zones
  /sys/devices/system/memory/memory32/valid_zones:Normal
  /sys/devices/system/memory/memory33/valid_zones:Normal
  /sys/devices/system/memory/memory34/valid_zones:Normal Movable

  $ echo online_movable > /sys/devices/system/memory/memory34/state
  $ grep . /sys/devices/system/memory/memory3?/valid_zones
  /sys/devices/system/memory/memory32/valid_zones:Normal
  /sys/devices/system/memory/memory33/valid_zones:Normal Movable
  /sys/devices/system/memory/memory34/valid_zones:Movable Normal

This is an awkward semantic because an udev event is sent as soon as the
block is onlined and an udev handler might want to online it based on
some policy (e.g.  association with a node) but it will inherently race
with new blocks showing up.

This patch changes the physical online phase to not associate pages with
any zone at all.  All the pages are just marked reserved and wait for
the onlining phase to be associated with the zone as per the online
request.  There are only two requirements

	- existing ZONE_NORMAL and ZONE_MOVABLE cannot overlap

	- ZONE_NORMAL precedes ZONE_MOVABLE in physical addresses

the latter one is not an inherent requirement and can be changed in the
future.  It preserves the current behavior and made the code slightly
simpler.  This is subject to change in future.

This means that the same physical online steps as above will lead to the
following state: Normal Movable

  /sys/devices/system/memory/memory32/valid_zones:Normal Movable
  /sys/devices/system/memory/memory33/valid_zones:Normal Movable

  /sys/devices/system/memory/memory32/valid_zones:Normal Movable
  /sys/devices/system/memory/memory33/valid_zones:Normal Movable
  /sys/devices/system/memory/memory34/valid_zones:Normal Movable

  /sys/devices/system/memory/memory32/valid_zones:Normal Movable
  /sys/devices/system/memory/memory33/valid_zones:Normal Movable
  /sys/devices/system/memory/memory34/valid_zones:Movable

Implementation:
The current move_pfn_range is reimplemented to check the above
requirements (allow_online_pfn_range) and then updates the respective
zone (move_pfn_range_to_zone), the pgdat and links all the pages in the
pfn range with the zone/node.  __add_pages is updated to not require the
zone and only initializes sections in the range.  This allowed to
simplify the arch_add_memory code (s390 could get rid of quite some of
code).

devm_memremap_pages is the only user of arch_add_memory which relies on
the zone association because it only hooks into the memory hotplug only
half way.  It uses it to associate the new memory with ZONE_DEVICE but
doesn't allow it to be {on,off}lined via sysfs.  This means that this
particular code path has to call move_pfn_range_to_zone explicitly.

The original zone shifting code is kept in place and will be removed in
the follow up patch for an easier review.

Please note that this patch also changes the original behavior when
offlining a memory block adjacent to another zone (Normal vs.  Movable)
used to allow to change its movable type.  This will be handled later.

[richard.weiyang@gmail.com: simplify zone_intersects()]
  Link: http://lkml.kernel.org/r/20170616092335.5177-1-richard.weiyang@gmail.com
[richard.weiyang@gmail.com: remove duplicate call for set_page_links]
  Link: http://lkml.kernel.org/r/20170616092335.5177-2-richard.weiyang@gmail.com
[akpm@linux-foundation.org: remove unused local `i']
Link: http://lkml.kernel.org/r/20170515085827.16474-12-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Tested-by: Dan Williams <dan.j.williams@intel.com>
Tested-by: Reza Arbab <arbab@linux.vnet.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> # For s390 bits
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Daniel Kiper <daniel.kiper@oracle.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Joonsoo Kim <js1304@gmail.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Tobias Regnery <tobias.regnery@gmail.com>
Cc: Toshi Kani <toshi.kani@hpe.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-06 16:24:32 -07:00
Michal Hocko 1b862aecfb mm, memory_hotplug: get rid of is_zone_device_section
Device memory hotplug hooks into regular memory hotplug only half way.
It needs memory sections to track struct pages but there is no
need/desire to associate those sections with memory blocks and export
them to the userspace via sysfs because they cannot be onlined anyway.

This is currently expressed by for_device argument to arch_add_memory
which then makes sure to associate the given memory range with
ZONE_DEVICE.  register_new_memory then relies on is_zone_device_section
to distinguish special memory hotplug from the regular one.  While this
works now, later patches in this series want to move __add_zone outside
of arch_add_memory path so we have to come up with something else.

Add want_memblock down the __add_pages path and use it to control
whether the section->memblock association should be done.
arch_add_memory then just trivially want memblock for everything but
for_device hotplug.

remove_memory_section doesn't need is_zone_device_section either.  We
can simply skip all the memblock specific cleanup if there is no
memblock for the given section.

This shouldn't introduce any functional change.

Link: http://lkml.kernel.org/r/20170515085827.16474-5-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Tested-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Daniel Kiper <daniel.kiper@oracle.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Joonsoo Kim <js1304@gmail.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Reza Arbab <arbab@linux.vnet.ibm.com>
Cc: Tobias Regnery <tobias.regnery@gmail.com>
Cc: Toshi Kani <toshi.kani@hpe.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-06 16:24:32 -07:00
Linus Torvalds 7a69f9c60b Merge branch 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 mm updates from Ingo Molnar:
 "The main changes in this cycle were:

   - Continued work to add support for 5-level paging provided by future
     Intel CPUs. In particular we switch the x86 GUP code to the generic
     implementation. (Kirill A. Shutemov)

   - Continued work to add PCID CPU support to native kernels as well.
     In this round most of the focus is on reworking/refreshing the TLB
     flush infrastructure for the upcoming PCID changes. (Andy
     Lutomirski)"

* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (34 commits)
  x86/mm: Delete a big outdated comment about TLB flushing
  x86/mm: Don't reenter flush_tlb_func_common()
  x86/KASLR: Fix detection 32/64 bit bootloaders for 5-level paging
  x86/ftrace: Exclude functions in head64.c from function-tracing
  x86/mmap, ASLR: Do not treat unlimited-stack tasks as legacy mmap
  x86/mm: Remove reset_lazy_tlbstate()
  x86/ldt: Simplify the LDT switching logic
  x86/boot/64: Put __startup_64() into .head.text
  x86/mm: Add support for 5-level paging for KASLR
  x86/mm: Make kernel_physical_mapping_init() support 5-level paging
  x86/mm: Add sync_global_pgds() for configuration with 5-level paging
  x86/boot/64: Add support of additional page table level during early boot
  x86/boot/64: Rename init_level4_pgt and early_level4_pgt
  x86/boot/64: Rewrite startup_64() in C
  x86/boot/compressed: Enable 5-level paging during decompression stage
  x86/boot/efi: Define __KERNEL32_CS GDT on 64-bit configurations
  x86/boot/efi: Fix __KERNEL_CS definition of GDT entry on 64-bit configurations
  x86/boot/efi: Cleanup initialization of GDT entries
  x86/asm: Fix comment in return_from_SYSCALL_64()
  x86/mm/gup: Switch GUP to the generic get_user_page_fast() implementation
  ...
2017-07-03 14:45:09 -07:00
Jérôme Glisse 98fe3633c5 x86/mm/hotplug: Fix BUG_ON() after hot-remove by not freeing PUD
Since commit:

  af2cf278ef ("x86/mm/hotplug: Don't remove PGD entries in remove_pagetable()")

we no longer free PUDs so that we do not have to synchronize
all PGDs on hot-remove/vfree().

But the new 5-level page table patchset reverted that for 4-level
page tables, in the following commit:

  f2a6a7050109: ("x86: Convert the rest of the code to support p4d_t")

This patch restores the damage and disables free_pud() if we are in the
4-level page table case, thus avoiding BUG_ON() after hot-remove.

Signed-off-by: Jérôme Glisse <jglisse@redhat.com>
[ Clarified the changelog and the code comments. ]
Reviewed-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Logan Gunthorpe <logang@deltatee.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20170624180514.3821-1-jglisse@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-26 11:44:19 +02:00