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  1. 08 Jan, 2018 2 commits
  2. 16 Nov, 2017 3 commits
    • Michal Hocko's avatar
      mm, sparse: do not swamp log with huge vmemmap allocation failures · fcdaf842
      Michal Hocko authored
      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.orgSigned-off-by: default avatarJohannes Weiner <hannes@cmpxchg.org>
      Signed-off-by: default avatarMichal 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: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      fcdaf842
    • Pavel Tatashin's avatar
      x86/mm: set fields in deferred pages · 353b1e7b
      Pavel Tatashin authored
      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.comSigned-off-by: default avatarPavel Tatashin <pasha.tatashin@oracle.com>
      Reviewed-by: default avatarSteven Sistare <steven.sistare@oracle.com>
      Reviewed-by: default avatarDaniel Jordan <daniel.m.jordan@oracle.com>
      Reviewed-by: default avatarBob Picco <bob.picco@oracle.com>
      Tested-by: default avatarBob Picco <bob.picco@oracle.com>
      Acked-by: default avatarMichal 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: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      353b1e7b
    • Levin, Alexander (Sasha Levin)'s avatar
      kmemcheck: stop using GFP_NOTRACK and SLAB_NOTRACK · 75f296d9
      Levin, Alexander (Sasha Levin) authored
      Convert all allocations that used a NOTRACK flag to stop using it.
      
      Link: http://lkml.kernel.org/r/20171007030159.22241-3-alexander.levin@verizon.comSigned-off-by: default avatarSasha 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: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      75f296d9
  3. 30 Oct, 2017 1 commit
  4. 09 Sep, 2017 1 commit
    • Michal Hocko's avatar
      mm/memory_hotplug: introduce add_pages · 3072e413
      Michal Hocko authored
      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.comSigned-off-by: default avatarMichal Hocko <mhocko@suse.com>
      Signed-off-by: default avatarJérôme Glisse <jglisse@redhat.com>
      Acked-by: default avatarBalbir 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: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      3072e413
  5. 06 Jul, 2017 3 commits
    • Michal Hocko's avatar
      mm, memory_hotplug: replace for_device by want_memblock in arch_add_memory · 3d79a728
      Michal Hocko authored
      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.orgSigned-off-by: default avatarMichal Hocko <mhocko@suse.com>
      Tested-by: default avatarDan Williams <dan.j.williams@intel.com>
      Acked-by: default avatarVlastimil 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: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      3d79a728
    • Michal Hocko's avatar
      mm, memory_hotplug: do not associate hotadded memory to zones until online · f1dd2cd1
      Michal Hocko authored
      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 9d99aaa3 ("[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 511c2aba ("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.orgSigned-off-by: default avatarMichal Hocko <mhocko@suse.com>
      Signed-off-by: default avatarWei Yang <richard.weiyang@gmail.com>
      Tested-by: default avatarDan Williams <dan.j.williams@intel.com>
      Tested-by: default avatarReza Arbab <arbab@linux.vnet.ibm.com>
      Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> # For s390 bits
      Acked-by: default avatarVlastimil 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: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      f1dd2cd1
    • Michal Hocko's avatar
      mm, memory_hotplug: get rid of is_zone_device_section · 1b862aec
      Michal Hocko authored
      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.orgSigned-off-by: default avatarMichal Hocko <mhocko@suse.com>
      Tested-by: default avatarDan Williams <dan.j.williams@intel.com>
      Acked-by: default avatarVlastimil 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: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      1b862aec
  6. 26 Jun, 2017 1 commit
  7. 13 Jun, 2017 2 commits
  8. 09 May, 2017 1 commit
  9. 05 May, 2017 1 commit
    • Baoquan He's avatar
      x86/mm: Fix boot crash caused by incorrect loop count calculation in sync_global_pgds() · fc5f9d5f
      Baoquan He authored
      Jeff Moyer reported that on his system with two memory regions 0~64G and
      1T~1T+192G, and kernel option "memmap=192G!1024G" added, enabling KASLR
      will make the system hang intermittently during boot. While adding 'nokaslr'
      won't.
      
      The back trace is:
      
       Oops: 0000 [#1] SMP
      
       RIP: memcpy_erms()
       [ .... ]
       Call Trace:
        pmem_rw_page()
        bdev_read_page()
        do_mpage_readpage()
        mpage_readpages()
        blkdev_readpages()
        __do_page_cache_readahead()
        force_page_cache_readahead()
        page_cache_sync_readahead()
        generic_file_read_iter()
        blkdev_read_iter()
        __vfs_read()
        vfs_read()
        SyS_read()
        entry_SYSCALL_64_fastpath()
      
      This crash happens because the for loop count calculation in sync_global_pgds()
      is not correct. When a mapping area crosses PGD entries, we should
      calculate the starting address of region which next PGD covers and assign
      it to next for loop count, but not add PGDIR_SIZE directly. The old
      code works right only if the mapping area is an exact multiple of PGDIR_SIZE,
      otherwize the end region could be skipped so that it can't be synchronized
      to all other processes from kernel PGD init_mm.pgd.
      
      In Jeff's system, emulated pmem area [1024G, 1216G) is smaller than
      PGDIR_SIZE. While 'nokaslr' works because PAGE_OFFSET is 1T aligned, it
      makes this area be mapped inside one PGD entry. With KASLR enabled,
      this area could cross two PGD entries, then the next PGD entry won't
      be synced to all other processes. That is why we saw empty PGD.
      
      Fix it.
      Reported-by: default avatarJeff Moyer <jmoyer@redhat.com>
      Signed-off-by: default avatarBaoquan He <bhe@redhat.com>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: Dan Williams <dan.j.williams@intel.com>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: Dave Young <dyoung@redhat.com>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Jinbum Park <jinb.park7@gmail.com>
      Cc: Josh Poimboeuf <jpoimboe@redhat.com>
      Cc: Kees Cook <keescook@chromium.org>
      Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Garnier <thgarnie@google.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Yasuaki Ishimatsu <yasu.isimatu@gmail.com>
      Cc: Yinghai Lu <yinghai@kernel.org>
      Link: http://lkml.kernel.org/r/1493864747-8506-1-git-send-email-bhe@redhat.comSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      fc5f9d5f
  10. 26 Apr, 2017 1 commit
  11. 27 Mar, 2017 1 commit
  12. 28 Feb, 2017 1 commit
  13. 23 Feb, 2017 1 commit
    • Yasuaki Ishimatsu's avatar
      mm/memory_hotplug: set magic number to page->freelist instead of page->lru.next · ddffe98d
      Yasuaki Ishimatsu authored
      To identify that pages of page table are allocated from bootmem
      allocator, magic number sets to page->lru.next.
      
      But page->lru list is initialized in reserve_bootmem_region().  So when
      calling free_pagetable(), the function cannot find the magic number of
      pages.  And free_pagetable() frees the pages by free_reserved_page() not
      put_page_bootmem().
      
      But if the pages are allocated from bootmem allocator and used as page
      table, the pages have private flag.  So before freeing the pages, we
      should clear the private flag by put_page_bootmem().
      
      Before applying the commit 7bfec6f4 ("mm, page_alloc: check multiple
      page fields with a single branch"), we could find the following visible
      issue:
      
        BUG: Bad page state in process kworker/u1024:1
        page:ffffea103cfd8040 count:0 mapcount:0 mappi
        flags: 0x6fffff80000800(private)
        page dumped because: PAGE_FLAGS_CHECK_AT_FREE flag(s) set
        bad because of flags: 0x800(private)
        <snip>
        Call Trace:
        [...] dump_stack+0x63/0x87
        [...] bad_page+0x114/0x130
        [...] free_pages_prepare+0x299/0x2d0
        [...] free_hot_cold_page+0x31/0x150
        [...] __free_pages+0x25/0x30
        [...] free_pagetable+0x6f/0xb4
        [...] remove_pagetable+0x379/0x7ff
        [...] vmemmap_free+0x10/0x20
        [...] sparse_remove_one_section+0x149/0x180
        [...] __remove_pages+0x2e9/0x4f0
        [...] arch_remove_memory+0x63/0xc0
        [...] remove_memory+0x8c/0xc0
        [...] acpi_memory_device_remove+0x79/0xa5
        [...] acpi_bus_trim+0x5a/0x8d
        [...] acpi_bus_trim+0x38/0x8d
        [...] acpi_device_hotplug+0x1b7/0x418
        [...] acpi_hotplug_work_fn+0x1e/0x29
        [...] process_one_work+0x152/0x400
        [...] worker_thread+0x125/0x4b0
        [...] kthread+0xd8/0xf0
        [...] ret_from_fork+0x22/0x40
      
      And the issue still silently occurs.
      
      Until freeing the pages of page table allocated from bootmem allocator,
      the page->freelist is never used.  So the patch sets magic number to
      page->freelist instead of page->lru.next.
      
      [isimatu.yasuaki@jp.fujitsu.com: fix merge issue]
        Link: http://lkml.kernel.org/r/722b1cc4-93ac-dd8b-2be2-7a7e313b3b0b@gmail.com
      Link: http://lkml.kernel.org/r/2c29bd9f-5b67-02d0-18a3-8828e78bbb6f@gmail.comSigned-off-by: default avatarYasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: Vlastimil Babka <vbabka@suse.cz>
      Cc: Mel Gorman <mgorman@techsingularity.net>
      Cc: Xishi Qiu <qiuxishi@huawei.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      ddffe98d
  14. 28 Jan, 2017 3 commits
    • Ingo Molnar's avatar
      x86/boot/e820: Prefix the E820_* type names with "E820_TYPE_" · 09821ff1
      Ingo Molnar authored
      So there's a number of constants that start with "E820" but which
      are not types - these create a confusing mixture when seen together
      with 'enum e820_type' values:
      
      	E820MAP
      	E820NR
      	E820_X_MAX
      	E820MAX
      
      To better differentiate the 'enum e820_type' values prefix them
      with E820_TYPE_.
      
      No change in functionality.
      
      Cc: Alex Thorlton <athorlton@sgi.com>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: Dan Williams <dan.j.williams@intel.com>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Huang, Ying <ying.huang@intel.com>
      Cc: Josh Poimboeuf <jpoimboe@redhat.com>
      Cc: Juergen Gross <jgross@suse.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Paul Jackson <pj@sgi.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Rafael J. Wysocki <rjw@sisk.pl>
      Cc: Tejun Heo <tj@kernel.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Wei Yang <richard.weiyang@gmail.com>
      Cc: Yinghai Lu <yinghai@kernel.org>
      Cc: linux-kernel@vger.kernel.org
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      09821ff1
    • Ingo Molnar's avatar
      x86/boot/e820: Rename e820_any_mapped()/e820_all_mapped() to e820__mapped_any()/e820__mapped_all() · 3bce64f0
      Ingo Molnar authored
      The 'any' and 'all' are modified to the 'mapped' concept, so move them last in the name.
      
      No change in functionality.
      
      Cc: Alex Thorlton <athorlton@sgi.com>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: Dan Williams <dan.j.williams@intel.com>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Huang, Ying <ying.huang@intel.com>
      Cc: Josh Poimboeuf <jpoimboe@redhat.com>
      Cc: Juergen Gross <jgross@suse.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Paul Jackson <pj@sgi.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Rafael J. Wysocki <rjw@sisk.pl>
      Cc: Tejun Heo <tj@kernel.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Wei Yang <richard.weiyang@gmail.com>
      Cc: Yinghai Lu <yinghai@kernel.org>
      Cc: linux-kernel@vger.kernel.org
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      3bce64f0
    • Ingo Molnar's avatar
      x86/boot/e820: Move asm/e820.h to asm/e820/api.h · 66441bd3
      Ingo Molnar authored
      In line with asm/e820/types.h, move the e820 API declarations to
      asm/e820/api.h and update all usage sites.
      
      This is just a mechanical, obviously correct move & replace patch,
      there will be subsequent changes to clean up the code and to make
      better use of the new header organization.
      
      Cc: Alex Thorlton <athorlton@sgi.com>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: Dan Williams <dan.j.williams@intel.com>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Huang, Ying <ying.huang@intel.com>
      Cc: Josh Poimboeuf <jpoimboe@redhat.com>
      Cc: Juergen Gross <jgross@suse.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Paul Jackson <pj@sgi.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Rafael J. Wysocki <rjw@sisk.pl>
      Cc: Tejun Heo <tj@kernel.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Wei Yang <richard.weiyang@gmail.com>
      Cc: Yinghai Lu <yinghai@kernel.org>
      Cc: linux-kernel@vger.kernel.org
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      66441bd3
  15. 24 Dec, 2016 1 commit
  16. 15 Dec, 2016 1 commit
  17. 15 Jul, 2016 1 commit
  18. 14 Jul, 2016 1 commit
    • Paul Gortmaker's avatar
      x86/mm: Audit and remove any unnecessary uses of module.h · 4b599fed
      Paul Gortmaker authored
      Historically a lot of these existed because we did not have
      a distinction between what was modular code and what was providing
      support to modules via EXPORT_SYMBOL and friends.  That changed
      when we forked out support for the latter into the export.h file.
      
      This means we should be able to reduce the usage of module.h
      in code that is obj-y Makefile or bool Kconfig.  The advantage
      in doing so is that module.h itself sources about 15 other headers;
      adding significantly to what we feed cpp, and it can obscure what
      headers we are effectively using.
      
      Since module.h was the source for init.h (for __init) and for
      export.h (for EXPORT_SYMBOL) we consider each obj-y/bool instance
      for the presence of either and replace accordingly where needed.
      
      Note that some bool/obj-y instances remain since module.h is
      the header for some exception table entry stuff, and for things
      like __init_or_module (code that is tossed when MODULES=n).
      Signed-off-by: default avatarPaul Gortmaker <paul.gortmaker@windriver.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Link: http://lkml.kernel.org/r/20160714001901.31603-3-paul.gortmaker@windriver.comSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      4b599fed
  19. 13 Jul, 2016 1 commit
    • Dave Hansen's avatar
      x86/mm: Use pte_none() to test for empty PTE · dcb32d99
      Dave Hansen authored
      The page table manipulation code seems to have grown a couple of
      sites that are looking for empty PTEs.  Just in case one of these
      entries got a stray bit set, use pte_none() instead of checking
      for a zero pte_val().
      
      The use pte_same() makes me a bit nervous.  If we were doing a
      pte_same() check against two cleared entries and one of them had
      a stray bit set, it might fail the pte_same() check.  But, I
      don't think we ever _do_ pte_same() for cleared entries.  It is
      almost entirely used for checking for races in fault-in paths.
      Signed-off-by: default avatarDave Hansen <dave.hansen@linux.intel.com>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: Dave Hansen <dave@sr71.net>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Josh Poimboeuf <jpoimboe@redhat.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Luis R. Rodriguez <mcgrof@suse.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Toshi Kani <toshi.kani@hp.com>
      Cc: dave.hansen@intel.com
      Cc: linux-mm@kvack.org
      Cc: mhocko@suse.com
      Link: http://lkml.kernel.org/r/20160708001915.813703D9@viggo.jf.intel.comSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      dcb32d99
  20. 08 Jul, 2016 2 commits
    • Thomas Garnier's avatar
      x86/mm: Add PUD VA support for physical mapping · faa37933
      Thomas Garnier authored
      Minor change that allows early boot physical mapping of PUD level virtual
      addresses. The current implementation expects the virtual address to be
      PUD aligned. For KASLR memory randomization, we need to be able to
      randomize the offset used on the PUD table.
      
      It has no impact on current usage.
      Signed-off-by: default avatarThomas Garnier <thgarnie@google.com>
      Signed-off-by: default avatarKees Cook <keescook@chromium.org>
      Cc: Alexander Kuleshov <kuleshovmail@gmail.com>
      Cc: Alexander Popov <alpopov@ptsecurity.com>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
      Cc: Baoquan He <bhe@redhat.com>
      Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Borislav Petkov <bp@suse.de>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: Christian Borntraeger <borntraeger@de.ibm.com>
      Cc: Dan Williams <dan.j.williams@intel.com>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: Dave Young <dyoung@redhat.com>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      Cc: Dmitry Vyukov <dvyukov@google.com>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Jan Beulich <JBeulich@suse.com>
      Cc: Joerg Roedel <jroedel@suse.de>
      Cc: Jonathan Corbet <corbet@lwn.net>
      Cc: Josh Poimboeuf <jpoimboe@redhat.com>
      Cc: Juergen Gross <jgross@suse.com>
      Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Lv Zheng <lv.zheng@intel.com>
      Cc: Mark Salter <msalter@redhat.com>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Matt Fleming <matt@codeblueprint.co.uk>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Stephen Smalley <sds@tycho.nsa.gov>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Toshi Kani <toshi.kani@hpe.com>
      Cc: Xiao Guangrong <guangrong.xiao@linux.intel.com>
      Cc: Yinghai Lu <yinghai@kernel.org>
      Cc: kernel-hardening@lists.openwall.com
      Cc: linux-doc@vger.kernel.org
      Link: http://lkml.kernel.org/r/1466556426-32664-4-git-send-email-keescook@chromium.orgSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      faa37933
    • Thomas Garnier's avatar
      x86/mm: Update physical mapping variable names · 59b3d020
      Thomas Garnier authored
      Change the variable names in kernel_physical_mapping_init() and related
      functions to correctly reflect physical and virtual memory addresses.
      Also add comments on each function to describe usage and alignment
      constraints.
      Signed-off-by: default avatarThomas Garnier <thgarnie@google.com>
      Signed-off-by: default avatarKees Cook <keescook@chromium.org>
      Cc: Alexander Kuleshov <kuleshovmail@gmail.com>
      Cc: Alexander Popov <alpopov@ptsecurity.com>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
      Cc: Baoquan He <bhe@redhat.com>
      Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Borislav Petkov <bp@suse.de>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: Christian Borntraeger <borntraeger@de.ibm.com>
      Cc: Dan Williams <dan.j.williams@intel.com>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: Dave Young <dyoung@redhat.com>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      Cc: Dmitry Vyukov <dvyukov@google.com>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Jan Beulich <JBeulich@suse.com>
      Cc: Joerg Roedel <jroedel@suse.de>
      Cc: Jonathan Corbet <corbet@lwn.net>
      Cc: Josh Poimboeuf <jpoimboe@redhat.com>
      Cc: Juergen Gross <jgross@suse.com>
      Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Lv Zheng <lv.zheng@intel.com>
      Cc: Mark Salter <msalter@redhat.com>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Matt Fleming <matt@codeblueprint.co.uk>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Stephen Smalley <sds@tycho.nsa.gov>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Toshi Kani <toshi.kani@hpe.com>
      Cc: Xiao Guangrong <guangrong.xiao@linux.intel.com>
      Cc: Yinghai Lu <yinghai@kernel.org>
      Cc: kernel-hardening@lists.openwall.com
      Cc: linux-doc@vger.kernel.org
      Link: http://lkml.kernel.org/r/1466556426-32664-3-git-send-email-keescook@chromium.orgSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      59b3d020
  21. 07 May, 2016 1 commit
    • Yinghai Lu's avatar
      x86/boot: Split out kernel_ident_mapping_init() · cf4fb15b
      Yinghai Lu authored
      In order to support on-demand page table creation when moving the
      kernel for KASLR, we need to use kernel_ident_mapping_init() in the
      decompression code.
      
      This splits it out into its own file for use outside of init_64.c.
      Additionally, checking for __pa/__va defines is added since they
      need to be overridden in the decompression code.
      
      [kees: rewrote changelog]
      Signed-off-by: default avatarYinghai Lu <yinghai@kernel.org>
      Signed-off-by: default avatarKees Cook <keescook@chromium.org>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Baoquan He <bhe@redhat.com>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Borislav Petkov <bp@suse.de>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: Dave Young <dyoung@redhat.com>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Vivek Goyal <vgoyal@redhat.com>
      Cc: kernel-hardening@lists.openwall.com
      Cc: lasse.collin@tukaani.org
      Link: http://lkml.kernel.org/r/1462572095-11754-3-git-send-email-keescook@chromium.orgSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      cf4fb15b
  22. 31 Mar, 2016 1 commit
  23. 22 Feb, 2016 1 commit
    • Kees Cook's avatar
      x86/mm: Always enable CONFIG_DEBUG_RODATA and remove the Kconfig option · 9ccaf77c
      Kees Cook authored
      This removes the CONFIG_DEBUG_RODATA option and makes it always enabled.
      
      This simplifies the code and also makes it clearer that read-only mapped
      memory is just as fundamental a security feature in kernel-space as it is
      in user-space.
      Suggested-by: default avatarIngo Molnar <mingo@kernel.org>
      Signed-off-by: default avatarKees Cook <keescook@chromium.org>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: Arnd Bergmann <arnd@arndb.de>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: David Brown <david.brown@linaro.org>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      Cc: Emese Revfy <re.emese@gmail.com>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Mathias Krause <minipli@googlemail.com>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: PaX Team <pageexec@freemail.hu>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: kernel-hardening@lists.openwall.com
      Cc: linux-arch <linux-arch@vger.kernel.org>
      Link: http://lkml.kernel.org/r/1455748879-21872-4-git-send-email-keescook@chromium.orgSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      9ccaf77c
  24. 19 Jan, 2016 1 commit
    • Seth Jennings's avatar
      x86/mm: Streamline and restore probe_memory_block_size() · 43c75f93
      Seth Jennings authored
      The cumulative effect of the following two commits:
      
        bdee237c ("x86: mm: Use 2GB memory block size on large-memory x86-64 systems")
        982792c7 ("x86, mm: probe memory block size for generic x86 64bit")
      
      ... is some pretty convoluted code.
      
      The first commit also removed code for the UV case without stated reason,
      which might lead to unexpected change in behavior.
      
      This commit has no other (intended) functional change; just seeks to simplify
      and make the code more understandable, beyond restoring the UV behavior.
      
      The whole section with the "tail size" doesn't seem to be
      reachable, since both the >= 64GB and < 64GB case return, so it
      was removed.
      Signed-off-by: default avatarSeth Jennings <sjennings@variantweb.net>
      Cc: Daniel J Blueman <daniel@numascale.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Yinghai Lu <yinghai@kernel.org>
      Link: http://lkml.kernel.org/r/1448902063-18885-1-git-send-email-sjennings@variantweb.net
      [ Rewrote the title and changelog. ]
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      43c75f93
  25. 16 Jan, 2016 1 commit
  26. 12 Jan, 2016 1 commit
  27. 09 Oct, 2015 1 commit
  28. 06 Oct, 2015 1 commit
    • Stephen Smalley's avatar
      x86/mm: Warn on W^X mappings · e1a58320
      Stephen Smalley authored
      Warn on any residual W+X mappings after setting NX
      if DEBUG_WX is enabled.  Introduce a separate
      X86_PTDUMP_CORE config that enables the code for
      dumping the page tables without enabling the debugfs
      interface, so that DEBUG_WX can be enabled without
      exposing the debugfs interface.  Switch EFI_PGT_DUMP
      to using X86_PTDUMP_CORE so that it also does not require
      enabling the debugfs interface.
      
      On success it prints this to the kernel log:
      
        x86/mm: Checked W+X mappings: passed, no W+X pages found.
      
      On failure it prints a warning and a count of the failed pages:
      
        ------------[ cut here ]------------
        WARNING: CPU: 1 PID: 1 at arch/x86/mm/dump_pagetables.c:226 note_page+0x610/0x7b0()
        x86/mm: Found insecure W+X mapping at address ffffffff81755000/__stop___ex_table+0xfa8/0xabfa8
        [...]
        Call Trace:
         [<ffffffff81380a5f>] dump_stack+0x44/0x55
         [<ffffffff8109d3f2>] warn_slowpath_common+0x82/0xc0
         [<ffffffff8109d48c>] warn_slowpath_fmt+0x5c/0x80
         [<ffffffff8106cfc9>] ? note_page+0x5c9/0x7b0
         [<ffffffff8106d010>] note_page+0x610/0x7b0
         [<ffffffff8106d409>] ptdump_walk_pgd_level_core+0x259/0x3c0
         [<ffffffff8106d5a7>] ptdump_walk_pgd_level_checkwx+0x17/0x20
         [<ffffffff81063905>] mark_rodata_ro+0xf5/0x100
         [<ffffffff817415a0>] ? rest_init+0x80/0x80
         [<ffffffff817415bd>] kernel_init+0x1d/0xe0
         [<ffffffff8174cd1f>] ret_from_fork+0x3f/0x70
         [<ffffffff817415a0>] ? rest_init+0x80/0x80
        ---[ end trace a1f23a1e42a2ac76 ]---
        x86/mm: Checked W+X mappings: FAILED, 171 W+X pages found.
      Signed-off-by: default avatarStephen Smalley <sds@tycho.nsa.gov>
      Acked-by: default avatarKees Cook <keescook@chromium.org>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: Arjan van de Ven <arjan@linux.intel.com>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Mike Galbraith <efault@gmx.de>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: linux-kernel@vger.kernel.org
      Link: http://lkml.kernel.org/r/1444064120-11450-1-git-send-email-sds@tycho.nsa.gov
      [ Improved the Kconfig help text and made the new option default-y
        if CONFIG_DEBUG_RODATA=y, because it already found buggy mappings,
        so we really want people to have this on by default. ]
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      e1a58320
  29. 02 Oct, 2015 1 commit
    • Stephen Smalley's avatar
      x86/mm: Set NX on gap between __ex_table and rodata · ab76f7b4
      Stephen Smalley authored
      Unused space between the end of __ex_table and the start of
      rodata can be left W+x in the kernel page tables.  Extend the
      setting of the NX bit to cover this gap by starting from
      text_end rather than rodata_start.
      
        Before:
        ---[ High Kernel Mapping ]---
        0xffffffff80000000-0xffffffff81000000          16M                               pmd
        0xffffffff81000000-0xffffffff81600000           6M     ro         PSE     GLB x  pmd
        0xffffffff81600000-0xffffffff81754000        1360K     ro                 GLB x  pte
        0xffffffff81754000-0xffffffff81800000         688K     RW                 GLB x  pte
        0xffffffff81800000-0xffffffff81a00000           2M     ro         PSE     GLB NX pmd
        0xffffffff81a00000-0xffffffff81b3b000        1260K     ro                 GLB NX pte
        0xffffffff81b3b000-0xffffffff82000000        4884K     RW                 GLB NX pte
        0xffffffff82000000-0xffffffff82200000           2M     RW         PSE     GLB NX pmd
        0xffffffff82200000-0xffffffffa0000000         478M                               pmd
      
        After:
        ---[ High Kernel Mapping ]---
        0xffffffff80000000-0xffffffff81000000          16M                               pmd
        0xffffffff81000000-0xffffffff81600000           6M     ro         PSE     GLB x  pmd
        0xffffffff81600000-0xffffffff81754000        1360K     ro                 GLB x  pte
        0xffffffff81754000-0xffffffff81800000         688K     RW                 GLB NX pte
        0xffffffff81800000-0xffffffff81a00000           2M     ro         PSE     GLB NX pmd
        0xffffffff81a00000-0xffffffff81b3b000        1260K     ro                 GLB NX pte
        0xffffffff81b3b000-0xffffffff82000000        4884K     RW                 GLB NX pte
        0xffffffff82000000-0xffffffff82200000           2M     RW         PSE     GLB NX pmd
        0xffffffff82200000-0xffffffffa0000000         478M                               pmd
      Signed-off-by: default avatarStephen Smalley <sds@tycho.nsa.gov>
      Acked-by: default avatarKees Cook <keescook@chromium.org>
      Cc: <stable@vger.kernel.org>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Mike Galbraith <efault@gmx.de>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: linux-kernel@vger.kernel.org
      Link: http://lkml.kernel.org/r/1443704662-3138-1-git-send-email-sds@tycho.nsa.govSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      ab76f7b4
  30. 27 Aug, 2015 1 commit
    • Dan Williams's avatar
      mm: ZONE_DEVICE for "device memory" · 033fbae9
      Dan Williams authored
      While pmem is usable as a block device or via DAX mappings to userspace
      there are several usage scenarios that can not target pmem due to its
      lack of struct page coverage. In preparation for "hot plugging" pmem
      into the vmemmap add ZONE_DEVICE as a new zone to tag these pages
      separately from the ones that are subject to standard page allocations.
      Importantly "device memory" can be removed at will by userspace
      unbinding the driver of the device.
      
      Having a separate zone prevents allocation and otherwise marks these
      pages that are distinct from typical uniform memory.  Device memory has
      different lifetime and performance characteristics than RAM.  However,
      since we have run out of ZONES_SHIFT bits this functionality currently
      depends on sacrificing ZONE_DMA.
      
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: Rik van Riel <riel@redhat.com>
      Cc: Mel Gorman <mgorman@suse.de>
      Cc: Jerome Glisse <j.glisse@gmail.com>
      [hch: various simplifications in the arch interface]
      Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
      Signed-off-by: default avatarDan Williams <dan.j.williams@intel.com>
      033fbae9
  31. 05 Mar, 2015 1 commit
    • Luis R. Rodriguez's avatar
      x86/mm: Use early_param_on_off() for direct_gbpages · 73c8c861
      Luis R. Rodriguez authored
      The enabler / disabler is pretty simple, just use the
      provided wrappers, this lets us easily relate the variable
      to the associated Kconfig entry.
      Signed-off-by: default avatarLuis R. Rodriguez <mcgrof@suse.com>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Borislav Petkov <bp@suse.de>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: David Vrabel <david.vrabel@citrix.com>
      Cc: Dexuan Cui <decui@microsoft.com>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: JBeulich@suse.com
      Cc: Jan Beulich <JBeulich@suse.com>
      Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
      Cc: Juergen Gross <jgross@suse.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Pavel Machek <pavel@ucw.cz>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Tony Lindgren <tony@atomide.com>
      Cc: Toshi Kani <toshi.kani@hp.com>
      Cc: Vlastimil Babka <vbabka@suse.cz>
      Cc: Xishi Qiu <qiuxishi@huawei.com>
      Cc: julia.lawall@lip6.fr
      Link: http://lkml.kernel.org/r/1425518654-3403-5-git-send-email-mcgrof@do-not-panic.comSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      73c8c861