1. 28 4月, 2020 7 次提交
    • B
      x86/resctrl: Initialize the vendor-specific resource functions · 77a3ed64
      Babu Moger 提交于
      to #26613714
      
      commit 1ad4fa41d99f606098fd7b90c1f5deb2b3dfae5d upstream.
      
      Initialize the resource functions that are different between the
      vendors. Some features are initialized differently between the vendors.
      Add _intel suffix to Intel-specific functions.
      
      For example, the MBA feature varies significantly between Intel and AMD.
      Separate the initialization of these resource functions. That way we can
      easily add AMD's functions later.
      Signed-off-by: NBabu Moger <babu.moger@amd.com>
      Signed-off-by: NBorislav Petkov <bp@suse.de>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Arnd Bergmann <arnd@arndb.de>
      Cc: Brijesh Singh <brijesh.singh@amd.com>
      Cc: "Chang S. Bae" <chang.seok.bae@intel.com>
      Cc: David Miller <davem@davemloft.net>
      Cc: David Woodhouse <dwmw2@infradead.org>
      Cc: Dmitry Safonov <dima@arista.com>
      Cc: Fenghua Yu <fenghua.yu@intel.com>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Jann Horn <jannh@google.com>
      Cc: Joerg Roedel <jroedel@suse.de>
      Cc: Jonathan Corbet <corbet@lwn.net>
      Cc: Josh Poimboeuf <jpoimboe@redhat.com>
      Cc: Kate Stewart <kstewart@linuxfoundation.org>
      Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
      Cc: <linux-doc@vger.kernel.org>
      Cc: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
      Cc: Paolo Bonzini <pbonzini@redhat.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Philippe Ombredanne <pombredanne@nexb.com>
      Cc: Pu Wen <puwen@hygon.cn>
      Cc: <qianyue.zj@alibaba-inc.com>
      Cc: "Rafael J. Wysocki" <rafael@kernel.org>
      Cc: Reinette Chatre <reinette.chatre@intel.com>
      Cc: Rian Hunter <rian@alum.mit.edu>
      Cc: Sherry Hurwitz <sherry.hurwitz@amd.com>
      Cc: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Thomas Lendacky <Thomas.Lendacky@amd.com>
      Cc: Tony Luck <tony.luck@intel.com>
      Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
      Cc: <xiaochen.shen@intel.com>
      Link: https://lkml.kernel.org/r/20181121202811.4492-6-babu.moger@amd.comSigned-off-by: NShile Zhang <shile.zhang@linux.alibaba.com>
      Tested-by: NWANG Siyuan <Siyuan.Wang@amd.com>
      Acked-by: NJoseph Qi <joseph.qi@linux.alibaba.com>
      77a3ed64
    • B
      x86/resctrl: Move all the macros to resctrl/internal.h · a7b49907
      Babu Moger 提交于
      to #26613714
      
      commit aa50453a448ad645ea05788505680aa403934aa8 upstream.
      
      Move all the macros to resctrl/internal.h and rename the registers with
      MSR_ prefix for consistency.
      
       [bp: align MSR definitions vertically ]
      Signed-off-by: NBabu Moger <babu.moger@amd.com>
      Signed-off-by: NBorislav Petkov <bp@suse.de>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Arnd Bergmann <arnd@arndb.de>
      Cc: Brijesh Singh <brijesh.singh@amd.com>
      Cc: "Chang S. Bae" <chang.seok.bae@intel.com>
      Cc: David Miller <davem@davemloft.net>
      Cc: David Woodhouse <dwmw2@infradead.org>
      Cc: Dmitry Safonov <dima@arista.com>
      Cc: Fenghua Yu <fenghua.yu@intel.com>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Jann Horn <jannh@google.com>
      Cc: Joerg Roedel <jroedel@suse.de>
      Cc: Jonathan Corbet <corbet@lwn.net>
      Cc: Josh Poimboeuf <jpoimboe@redhat.com>
      Cc: Kate Stewart <kstewart@linuxfoundation.org>
      Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
      Cc: <linux-doc@vger.kernel.org>
      Cc: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
      Cc: Paolo Bonzini <pbonzini@redhat.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Philippe Ombredanne <pombredanne@nexb.com>
      Cc: Pu Wen <puwen@hygon.cn>
      Cc: <qianyue.zj@alibaba-inc.com>
      Cc: "Rafael J. Wysocki" <rafael@kernel.org>
      Cc: Reinette Chatre <reinette.chatre@intel.com>
      Cc: Rian Hunter <rian@alum.mit.edu>
      Cc: Sherry Hurwitz <sherry.hurwitz@amd.com>
      Cc: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Thomas Lendacky <Thomas.Lendacky@amd.com>
      Cc: Tony Luck <tony.luck@intel.com>
      Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
      Cc: <xiaochen.shen@intel.com>
      Link: https://lkml.kernel.org/r/20181121202811.4492-5-babu.moger@amd.comSigned-off-by: NShile Zhang <shile.zhang@linux.alibaba.com>
      Tested-by: NWANG Siyuan <Siyuan.Wang@amd.com>
      Acked-by: NJoseph Qi <joseph.qi@linux.alibaba.com>
      a7b49907
    • B
      x86/resctrl: Re-arrange the RDT init code · 0d7d96de
      Babu Moger 提交于
      to #26613714
      
      commit 0f00717ecce4b366b3f530153e982cb2eeadafd1 upstream.
      
      Separate the call sequence for rdt_quirks and MBA feature. This is in
      preparation to handle vendor differences in these call sequences. Rename
      the functions to make the flow a bit more meaningful.
      Signed-off-by: NBabu Moger <babu.moger@amd.com>
      Signed-off-by: NBorislav Petkov <bp@suse.de>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Arnd Bergmann <arnd@arndb.de>
      Cc: Brijesh Singh <brijesh.singh@amd.com>
      Cc: "Chang S. Bae" <chang.seok.bae@intel.com>
      Cc: David Miller <davem@davemloft.net>
      Cc: David Woodhouse <dwmw2@infradead.org>
      Cc: Dmitry Safonov <dima@arista.com>
      Cc: Fenghua Yu <fenghua.yu@intel.com>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Jann Horn <jannh@google.com>
      Cc: Joerg Roedel <jroedel@suse.de>
      Cc: Jonathan Corbet <corbet@lwn.net>
      Cc: Josh Poimboeuf <jpoimboe@redhat.com>
      Cc: Kate Stewart <kstewart@linuxfoundation.org>
      Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
      Cc: <linux-doc@vger.kernel.org>
      Cc: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
      Cc: Paolo Bonzini <pbonzini@redhat.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Philippe Ombredanne <pombredanne@nexb.com>
      Cc: Pu Wen <puwen@hygon.cn>
      Cc: <qianyue.zj@alibaba-inc.com>
      Cc: "Rafael J. Wysocki" <rafael@kernel.org>
      Cc: Reinette Chatre <reinette.chatre@intel.com>
      Cc: Rian Hunter <rian@alum.mit.edu>
      Cc: Sherry Hurwitz <sherry.hurwitz@amd.com>
      Cc: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Thomas Lendacky <Thomas.Lendacky@amd.com>
      Cc: Tony Luck <tony.luck@intel.com>
      Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
      Cc: <xiaochen.shen@intel.com>
      Cc: x86-ml <x86@kernel.org>
      Link: https://lkml.kernel.org/r/20181121202811.4492-4-babu.moger@amd.comSigned-off-by: NShile Zhang <shile.zhang@linux.alibaba.com>
      Tested-by: NWANG Siyuan <Siyuan.Wang@amd.com>
      Acked-by: NJoseph Qi <joseph.qi@linux.alibaba.com>
      0d7d96de
    • B
      x86/resctrl: Rename the RDT functions and definitions · 51947221
      Babu Moger 提交于
      to #26613714
      
      commit 352940ececaca58536a7fc4ff6b41d181156fd65 upstream.
      
      As AMD is starting to support RESCTRL features, rename the RDT functions
      and definitions to more generic names.
      
      Replace "intel_rdt" with "resctrl" where applicable.
      Signed-off-by: NBabu Moger <babu.moger@amd.com>
      Signed-off-by: NBorislav Petkov <bp@suse.de>
      Reviewed-by: NBorislav Petkov <bp@suse.de>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Arnd Bergmann <arnd@arndb.de>
      Cc: Brijesh Singh <brijesh.singh@amd.com>
      Cc: "Chang S. Bae" <chang.seok.bae@intel.com>
      Cc: David Miller <davem@davemloft.net>
      Cc: David Woodhouse <dwmw2@infradead.org>
      Cc: Dmitry Safonov <dima@arista.com>
      Cc: Fenghua Yu <fenghua.yu@intel.com>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Jann Horn <jannh@google.com>
      Cc: Joerg Roedel <jroedel@suse.de>
      Cc: Jonathan Corbet <corbet@lwn.net>
      Cc: Josh Poimboeuf <jpoimboe@redhat.com>
      Cc: Kate Stewart <kstewart@linuxfoundation.org>
      Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
      Cc: <linux-doc@vger.kernel.org>
      Cc: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
      Cc: Paolo Bonzini <pbonzini@redhat.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Philippe Ombredanne <pombredanne@nexb.com>
      Cc: Pu Wen <puwen@hygon.cn>
      Cc: <qianyue.zj@alibaba-inc.com>
      Cc: "Rafael J. Wysocki" <rafael@kernel.org>
      Cc: Reinette Chatre <reinette.chatre@intel.com>
      Cc: Rian Hunter <rian@alum.mit.edu>
      Cc: Sherry Hurwitz <sherry.hurwitz@amd.com>
      Cc: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Thomas Lendacky <Thomas.Lendacky@amd.com>
      Cc: Tony Luck <tony.luck@intel.com>
      Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
      Cc: <xiaochen.shen@intel.com>
      Link: https://lkml.kernel.org/r/20181121202811.4492-3-babu.moger@amd.comSigned-off-by: NShile Zhang <shile.zhang@linux.alibaba.com>
      Tested-by: NWANG Siyuan <Siyuan.Wang@amd.com>
      Acked-by: NJoseph Qi <joseph.qi@linux.alibaba.com>
      51947221
    • B
      x86/resctrl: Rename and move rdt files to a separate directory · ad6da85b
      Babu Moger 提交于
      to #26613714
      
      commit fa7d949337ccad32c76740c88e0e0351c349053b upstream.
      
      New generation of AMD processors add support for RDT (or QOS) features.
      Together, these features will be called RESCTRL. With more than one
      vendors supporting these features, it seems more appropriate to rename
      these files.
      
      Create a new directory with the name 'resctrl' and move all the
      intel_rdt files to the new directory. This way all the resctrl related
      code resides inside one directory.
      
       [ bp: Add SPDX identifier to the Makefile ]
      Suggested-by: NBorislav Petkov <bp@suse.de>
      Signed-off-by: NBabu Moger <babu.moger@amd.com>
      Signed-off-by: NBorislav Petkov <bp@suse.de>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Arnd Bergmann <arnd@arndb.de>
      Cc: Brijesh Singh <brijesh.singh@amd.com>
      Cc: "Chang S. Bae" <chang.seok.bae@intel.com>
      Cc: David Miller <davem@davemloft.net>
      Cc: David Woodhouse <dwmw2@infradead.org>
      Cc: Dmitry Safonov <dima@arista.com>
      Cc: Fenghua Yu <fenghua.yu@intel.com>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Jann Horn <jannh@google.com>
      Cc: Joerg Roedel <jroedel@suse.de>
      Cc: Jonathan Corbet <corbet@lwn.net>
      Cc: Josh Poimboeuf <jpoimboe@redhat.com>
      Cc: Kate Stewart <kstewart@linuxfoundation.org>
      Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
      Cc: <linux-doc@vger.kernel.org>
      Cc: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
      Cc: Paolo Bonzini <pbonzini@redhat.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Philippe Ombredanne <pombredanne@nexb.com>
      Cc: Pu Wen <puwen@hygon.cn>
      Cc: <qianyue.zj@alibaba-inc.com>
      Cc: "Rafael J. Wysocki" <rafael@kernel.org>
      Cc: Reinette Chatre <reinette.chatre@intel.com>
      Cc: Rian Hunter <rian@alum.mit.edu>
      Cc: Sherry Hurwitz <sherry.hurwitz@amd.com>
      Cc: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Thomas Lendacky <Thomas.Lendacky@amd.com>
      Cc: Tony Luck <tony.luck@intel.com>
      Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
      Cc: <xiaochen.shen@intel.com>
      Link: https://lkml.kernel.org/r/20181121202811.4492-2-babu.moger@amd.com
      
      [ Shile: fixed conflict in arch/x86/kernel/cpu/resctrl/pseudo_lock.c ]
      Signed-off-by: NShile Zhang <shile.zhang@linux.alibaba.com>
      Tested-by: NWANG Siyuan <Siyuan.Wang@amd.com>
      Acked-by: NJoseph Qi <joseph.qi@linux.alibaba.com>
      ad6da85b
    • R
      mm: mempolicy: require at least one nodeid for MPOL_PREFERRED · fd0d6625
      Randy Dunlap 提交于
      to #24913189, fixes CVE-2020-11565.
      
      commit aa9f7d5172fac9bf1f09e678c35e287a40a7b7dd upstream.
      
      Using an empty (malformed) nodelist that is not caught during mount option
      parsing leads to a stack-out-of-bounds access.
      
      The option string that was used was: "mpol=prefer:,".  However,
      MPOL_PREFERRED requires a single node number, which is not being provided
      here.
      
      Add a check that 'nodes' is not empty after parsing for MPOL_PREFERRED's
      nodeid.
      
      Fixes: 095f1fc4 ("mempolicy: rework shmem mpol parsing and display")
      Reported-by: NEntropy Moe <3ntr0py1337@gmail.com>
      Reported-by: syzbot+b055b1a6b2b958707a21@syzkaller.appspotmail.com
      Signed-off-by: NRandy Dunlap <rdunlap@infradead.org>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Tested-by: syzbot+b055b1a6b2b958707a21@syzkaller.appspotmail.com
      Cc: Lee Schermerhorn <lee.schermerhorn@hp.com>
      Link: http://lkml.kernel.org/r/89526377-7eb6-b662-e1d8-4430928abde9@infradead.orgSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: NShile Zhang <shile.zhang@linux.alibaba.com>
      Acked-by: NJoseph Qi <joseph.qi@linux.alibaba.com>
      fd0d6625
    • S
      af776790
  2. 27 4月, 2020 1 次提交
  3. 26 4月, 2020 5 次提交
  4. 24 4月, 2020 13 次提交
  5. 23 4月, 2020 14 次提交
    • V
      mm, compaction: fully assume capture is not NULL in compact_zone_order() · 087f53fc
      Vlastimil Babka 提交于
      to #26255339
      
      commit 6467552ca64c4ddd2b83ed73192107d7145f533b upstream
      
      Dan reports:
      
      The patch 5e1f0f098b46: "mm, compaction: capture a page under direct
      compaction" from Mar 5, 2019, leads to the following Smatch complaint:
      
          mm/compaction.c:2321 compact_zone_order()
           error: we previously assumed 'capture' could be null (see line 2313)
      
      mm/compaction.c
        2288  static enum compact_result compact_zone_order(struct zone *zone, int order,
        2289                  gfp_t gfp_mask, enum compact_priority prio,
        2290                  unsigned int alloc_flags, int classzone_idx,
        2291                  struct page **capture)
                                            ^^^^^^^
      
        2313		if (capture)
                          ^^^^^^^
      Check for NULL
      
        2314			current->capture_control = &capc;
        2315
        2316		ret = compact_zone(&cc, &capc);
        2317
        2318		VM_BUG_ON(!list_empty(&cc.freepages));
        2319		VM_BUG_ON(!list_empty(&cc.migratepages));
        2320
        2321		*capture = capc.page;
                      ^^^^^^^^
      Unchecked dereference.
      
        2322		current->capture_control = NULL;
        2323
      
      In practice this is not an issue, as the only caller path passes non-NULL
      capture:
      
      __alloc_pages_direct_compact()
        struct page *page = NULL;
        try_to_compact_pages(capture = &page);
          compact_zone_order(capture = capture);
      
      So let's remove the unnecessary check, which should also make Smatch happy.
      
      Fixes: 5e1f0f098b46 ("mm, compaction: capture a page under direct compaction")
      Reported-by: NDan Carpenter <dan.carpenter@oracle.com>
      Suggested-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NVlastimil Babka <vbabka@suse.cz>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Reviewed-by: NAndrew Morton <akpm@linux-foundation.org>
      Acked-by: NMel Gorman <mgorman@techsingularity.net>
      Link: http://lkml.kernel.org/r/18b0df3c-0589-d96c-23fa-040798fee187@suse.czSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: NYang Shi <yang.shi@linux.alibaba.com>
      Reviewed-by: NXunlei Pang <xlpang@linux.alibaba.com>
      087f53fc
    • J
      mm/compaction: add missing annotation for compact_lock_irqsave · 61d6ab62
      Jules Irenge 提交于
      to #26255339
      
      commit 77337edee7598d82fb5acf66cb91a5b3f0c46add upstream
      
      Sparse reports a warning at compact_lock_irqsave()
      
      warning: context imbalance in compact_lock_irqsave() - wrong count at exit
      
      The root cause is the missing annotation at compact_lock_irqsave()
      Add the missing __acquires(lock) annotation.
      Signed-off-by: NJules Irenge <jbi.octave@gmail.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Link: http://lkml.kernel.org/r/20200214204741.94112-6-jbi.octave@gmail.comSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: NYang Shi <yang.shi@linux.alibaba.com>
      Reviewed-by: NXunlei Pang <xlpang@linux.alibaba.com>
      61d6ab62
    • V
      mm, compaction: fix wrong pfn handling in __reset_isolation_pfn() · a5c295c0
      Vlastimil Babka 提交于
      to #26255339
      
      commit a2e9a5afce080226edbf1882d63d99bf32070e9e upstream
      
      Florian and Dave reported [1] a NULL pointer dereference in
      __reset_isolation_pfn().  While the exact cause is unclear, staring at
      the code revealed two bugs, which might be related.
      
      One bug is that if zone starts in the middle of pageblock, block_page
      might correspond to different pfn than block_pfn, and then the
      pfn_valid_within() checks will check different pfn's than those accessed
      via struct page.  This might result in acessing an unitialized page in
      CONFIG_HOLES_IN_ZONE configs.
      
      The other bug is that end_page refers to the first page of next
      pageblock and not last page of current pageblock.  The online and valid
      check is then wrong and with sections, the while (page < end_page) loop
      might wander off actual struct page arrays.
      
      [1] https://lore.kernel.org/linux-xfs/87o8z1fvqu.fsf@mid.deneb.enyo.de/
      
      Link: http://lkml.kernel.org/r/20191008152915.24704-1-vbabka@suse.cz
      Fixes: 6b0868c820ff ("mm/compaction.c: correct zone boundary handling when resetting pageblock skip hints")
      Signed-off-by: NVlastimil Babka <vbabka@suse.cz>
      Reported-by: NFlorian Weimer <fw@deneb.enyo.de>
      Reported-by: NDave Chinner <david@fromorbit.com>
      Acked-by: NMel Gorman <mgorman@techsingularity.net>
      Cc: <stable@vger.kernel.org>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: NYang Shi <yang.shi@linux.alibaba.com>
      Reviewed-by: NXunlei Pang <xlpang@linux.alibaba.com>
      a5c295c0
    • P
      mm/compaction.c: remove unnecessary zone parameter in isolate_migratepages() · 57405fb9
      Pengfei Li 提交于
      to #26255339
      
      commit 32aaf0553df99cc4314f6e9f43216cd83afc6c20 upstream
      
      Like commit 40cacbcb3240 ("mm, compaction: remove unnecessary zone
      parameter in some instances"), remove unnecessary zone parameter.
      
      No functional change.
      
      Link: http://lkml.kernel.org/r/20190806151616.21107-1-lpf.vector@gmail.comSigned-off-by: NPengfei Li <lpf.vector@gmail.com>
      Reviewed-by: NAndrew Morton <akpm@linux-foundation.org>
      Acked-by: NVlastimil Babka <vbabka@suse.cz>
      Cc: Mel Gorman <mgorman@techsingularity.net>
      Cc: Qian Cai <cai@lca.pw>
      Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: NYang Shi <yang.shi@linux.alibaba.com>
      Reviewed-by: NXunlei Pang <xlpang@linux.alibaba.com>
      57405fb9
    • Y
      mm/compaction.c: clear total_{migrate,free}_scanned before scanning a new zone · 8539ae81
      Yafang Shao 提交于
      to #26255339
      
      commit a94b525241c0fff3598809131d7cfcfe1d572d8c upstream
      
      total_{migrate,free}_scanned will be added to COMPACTMIGRATE_SCANNED and
      COMPACTFREE_SCANNED in compact_zone().  We should clear them before
      scanning a new zone.  In the proc triggered compaction, we forgot clearing
      them.
      
      [laoar.shao@gmail.com: introduce a helper compact_zone_counters_init()]
        Link: http://lkml.kernel.org/r/1563869295-25748-1-git-send-email-laoar.shao@gmail.com
      [akpm@linux-foundation.org: expand compact_zone_counters_init() into its single callsite, per mhocko]
      [vbabka@suse.cz: squash compact_zone() list_head init as well]
        Link: http://lkml.kernel.org/r/1fb6f7da-f776-9e42-22f8-bbb79b030b98@suse.cz
      [akpm@linux-foundation.org: kcompactd_do_work(): avoid unnecessary initialization of cc.zone]
      Link: http://lkml.kernel.org/r/1563789275-9639-1-git-send-email-laoar.shao@gmail.com
      Fixes: 7f354a54 ("mm, compaction: add vmstats for kcompactd work")
      Signed-off-by: NYafang Shao <laoar.shao@gmail.com>
      Signed-off-by: NVlastimil Babka <vbabka@suse.cz>
      Reviewed-by: NVlastimil Babka <vbabka@suse.cz>
      Cc: David Rientjes <rientjes@google.com>
      Cc: Yafang Shao <shaoyafang@didiglobal.com>
      Cc: Mel Gorman <mgorman@techsingularity.net>
      Cc: Michal Hocko <mhocko@suse.com>
      Cc: <stable@vger.kernel.org>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: NYang Shi <yang.shi@linux.alibaba.com>
      Reviewed-by: NXunlei Pang <xlpang@linux.alibaba.com>
      8539ae81
    • M
      mm: compaction: avoid 100% CPU usage during compaction when a task is killed · 377f424a
      Mel Gorman 提交于
      to #26255339
      
      commit 670105a25608affe01cb0ccdc2a1f4bd2327172b upstream
      
      "howaboutsynergy" reported via kernel buzilla number 204165 that
      compact_zone_order was consuming 100% CPU during a stress test for
      prolonged periods of time.  Specifically the following command, which
      should exit in 10 seconds, was taking an excessive time to finish while
      the CPU was pegged at 100%.
      
        stress -m 220 --vm-bytes 1000000000 --timeout 10
      
      Tracing indicated a pattern as follows
      
                stress-3923  [007]   519.106208: mm_compaction_isolate_migratepages: range=(0x70bb80 ~ 0x70bb80) nr_scanned=0 nr_taken=0
                stress-3923  [007]   519.106212: mm_compaction_isolate_migratepages: range=(0x70bb80 ~ 0x70bb80) nr_scanned=0 nr_taken=0
                stress-3923  [007]   519.106216: mm_compaction_isolate_migratepages: range=(0x70bb80 ~ 0x70bb80) nr_scanned=0 nr_taken=0
                stress-3923  [007]   519.106219: mm_compaction_isolate_migratepages: range=(0x70bb80 ~ 0x70bb80) nr_scanned=0 nr_taken=0
                stress-3923  [007]   519.106223: mm_compaction_isolate_migratepages: range=(0x70bb80 ~ 0x70bb80) nr_scanned=0 nr_taken=0
                stress-3923  [007]   519.106227: mm_compaction_isolate_migratepages: range=(0x70bb80 ~ 0x70bb80) nr_scanned=0 nr_taken=0
                stress-3923  [007]   519.106231: mm_compaction_isolate_migratepages: range=(0x70bb80 ~ 0x70bb80) nr_scanned=0 nr_taken=0
                stress-3923  [007]   519.106235: mm_compaction_isolate_migratepages: range=(0x70bb80 ~ 0x70bb80) nr_scanned=0 nr_taken=0
                stress-3923  [007]   519.106238: mm_compaction_isolate_migratepages: range=(0x70bb80 ~ 0x70bb80) nr_scanned=0 nr_taken=0
                stress-3923  [007]   519.106242: mm_compaction_isolate_migratepages: range=(0x70bb80 ~ 0x70bb80) nr_scanned=0 nr_taken=0
      
      Note that compaction is entered in rapid succession while scanning and
      isolating nothing.  The problem is that when a task that is compacting
      receives a fatal signal, it retries indefinitely instead of exiting
      while making no progress as a fatal signal is pending.
      
      It's not easy to trigger this condition although enabling zswap helps on
      the basis that the timing is altered.  A very small window has to be hit
      for the problem to occur (signal delivered while compacting and
      isolating a PFN for migration that is not aligned to SWAP_CLUSTER_MAX).
      
      This was reproduced locally -- 16G single socket system, 8G swap, 30%
      zswap configured, vm-bytes 22000000000 using Colin Kings stress-ng
      implementation from github running in a loop until the problem hits).
      Tracing recorded the problem occurring almost 200K times in a short
      window.  With this patch, the problem hit 4 times but the task existed
      normally instead of consuming CPU.
      
      This problem has existed for some time but it was made worse by commit
      cf66f0700c8f ("mm, compaction: do not consider a need to reschedule as
      contention").  Before that commit, if the same condition was hit then
      locks would be quickly contended and compaction would exit that way.
      
      Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=204165
      Link: http://lkml.kernel.org/r/20190718085708.GE24383@techsingularity.net
      Fixes: cf66f0700c8f ("mm, compaction: do not consider a need to reschedule as contention")
      Signed-off-by: NMel Gorman <mgorman@techsingularity.net>
      Reviewed-by: NVlastimil Babka <vbabka@suse.cz>
      Cc: <stable@vger.kernel.org>    [5.1+]
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: NYang Shi <yang.shi@linux.alibaba.com>
      Reviewed-by: NXunlei Pang <xlpang@linux.alibaba.com>
      377f424a
    • S
      mm, compaction: make sure we isolate a valid PFN · 89c885ab
      Suzuki K Poulose 提交于
      to #26255339
      
      commit e577c8b64d58fe307ea4d5149d31615df2d90861 upstream
      
      When we have holes in a normal memory zone, we could endup having
      cached_migrate_pfns which may not necessarily be valid, under heavy memory
      pressure with swapping enabled ( via __reset_isolation_suitable(),
      triggered by kswapd).
      
      Later if we fail to find a page via fast_isolate_freepages(), we may end
      up using the migrate_pfn we started the search with, as valid page.  This
      could lead to accessing NULL pointer derefernces like below, due to an
      invalid mem_section pointer.
      
      Unable to handle kernel NULL pointer dereference at virtual address 0000000000000008 [47/1825]
       Mem abort info:
         ESR = 0x96000004
         Exception class = DABT (current EL), IL = 32 bits
         SET = 0, FnV = 0
         EA = 0, S1PTW = 0
       Data abort info:
         ISV = 0, ISS = 0x00000004
         CM = 0, WnR = 0
       user pgtable: 4k pages, 48-bit VAs, pgdp = 0000000082f94ae9
       [0000000000000008] pgd=0000000000000000
       Internal error: Oops: 96000004 [#1] SMP
       ...
       CPU: 10 PID: 6080 Comm: qemu-system-aar Not tainted 510-rc1+ #6
       Hardware name: AmpereComputing(R) OSPREY EV-883832-X3-0001/OSPREY, BIOS 4819 09/25/2018
       pstate: 60000005 (nZCv daif -PAN -UAO)
       pc : set_pfnblock_flags_mask+0x58/0xe8
       lr : compaction_alloc+0x300/0x950
       [...]
       Process qemu-system-aar (pid: 6080, stack limit = 0x0000000095070da5)
       Call trace:
        set_pfnblock_flags_mask+0x58/0xe8
        compaction_alloc+0x300/0x950
        migrate_pages+0x1a4/0xbb0
        compact_zone+0x750/0xde8
        compact_zone_order+0xd8/0x118
        try_to_compact_pages+0xb4/0x290
        __alloc_pages_direct_compact+0x84/0x1e0
        __alloc_pages_nodemask+0x5e0/0xe18
        alloc_pages_vma+0x1cc/0x210
        do_huge_pmd_anonymous_page+0x108/0x7c8
        __handle_mm_fault+0xdd4/0x1190
        handle_mm_fault+0x114/0x1c0
        __get_user_pages+0x198/0x3c0
        get_user_pages_unlocked+0xb4/0x1d8
        __gfn_to_pfn_memslot+0x12c/0x3b8
        gfn_to_pfn_prot+0x4c/0x60
        kvm_handle_guest_abort+0x4b0/0xcd8
        handle_exit+0x140/0x1b8
        kvm_arch_vcpu_ioctl_run+0x260/0x768
        kvm_vcpu_ioctl+0x490/0x898
        do_vfs_ioctl+0xc4/0x898
        ksys_ioctl+0x8c/0xa0
        __arm64_sys_ioctl+0x28/0x38
        el0_svc_common+0x74/0x118
        el0_svc_handler+0x38/0x78
        el0_svc+0x8/0xc
       Code: f8607840 f100001f 8b011401 9a801020 (f9400400)
       ---[ end trace af6a35219325a9b6 ]---
      
      The issue was reported on an arm64 server with 128GB with holes in the
      zone (e.g, [32GB@4GB, 96GB@544GB]), with a swap device enabled, while
      running 100 KVM guest instances.
      
      This patch fixes the issue by ensuring that the page belongs to a valid
      PFN when we fallback to using the lower limit of the scan range upon
      failure in fast_isolate_freepages().
      
      Link: http://lkml.kernel.org/r/1558711908-15688-1-git-send-email-suzuki.poulose@arm.com
      Fixes: 5a811889de10f1eb ("mm, compaction: use free lists to quickly locate a migration target")
      Signed-off-by: NSuzuki K Poulose <suzuki.poulose@arm.com>
      Reported-by: NMarc Zyngier <marc.zyngier@arm.com>
      Reviewed-by: NMel Gorman <mgorman@techsingularity.net>
      Reviewed-by: NAnshuman Khandual <anshuman.khandual@arm.com>
      Cc: Michal Hocko <mhocko@suse.com>
      Cc: Qian Cai <cai@lca.pw>
      Cc: Marc Zyngier <marc.zyngier@arm.com>
      Cc: <stable@vger.kernel.org>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: NYang Shi <yang.shi@linux.alibaba.com>
      Reviewed-by: NXunlei Pang <xlpang@linux.alibaba.com>
      89c885ab
    • M
      mm/compaction.c: correct zone boundary handling when isolating pages from a pageblock · 39470173
      Mel Gorman 提交于
      to #26255339
      
      commit 60fce36afa9c77c7ccbf980c4f670f3be3651fce upstream
      
      syzbot reported the following error from a tree with a head commit of
      baf76f0c58ae ("slip: make slhc_free() silently accept an error pointer")
      
        BUG: unable to handle kernel paging request at ffffea0003348000
        #PF error: [normal kernel read fault]
        PGD 12c3f9067 P4D 12c3f9067 PUD 12c3f8067 PMD 0
        Oops: 0000 [#1] PREEMPT SMP KASAN
        CPU: 1 PID: 28916 Comm: syz-executor.2 Not tainted 5.1.0-rc6+ #89
        Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
        RIP: 0010:constant_test_bit arch/x86/include/asm/bitops.h:314 [inline]
        RIP: 0010:PageCompound include/linux/page-flags.h:186 [inline]
        RIP: 0010:isolate_freepages_block+0x1c0/0xd40 mm/compaction.c:579
        Code: 01 d8 ff 4d 85 ed 0f 84 ef 07 00 00 e8 29 00 d8 ff 4c 89 e0 83 85 38 ff
        ff ff 01 48 c1 e8 03 42 80 3c 38 00 0f 85 31 0a 00 00 <4d> 8b 2c 24 31 ff 49
        c1 ed 10 41 83 e5 01 44 89 ee e8 3a 01 d8 ff
        RSP: 0018:ffff88802b31eab8 EFLAGS: 00010246
        RAX: 1ffffd4000669000 RBX: 00000000000cd200 RCX: ffffc9000a235000
        RDX: 000000000001ca5e RSI: ffffffff81988cc7 RDI: 0000000000000001
        RBP: ffff88802b31ebd8 R08: ffff88805af700c0 R09: 0000000000000000
        R10: 0000000000000000 R11: 0000000000000000 R12: ffffea0003348000
        R13: 0000000000000000 R14: ffff88802b31f030 R15: dffffc0000000000
        FS:  00007f61648dc700(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
        CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
        CR2: ffffea0003348000 CR3: 0000000037c64000 CR4: 00000000001426e0
        Call Trace:
         fast_isolate_around mm/compaction.c:1243 [inline]
         fast_isolate_freepages mm/compaction.c:1418 [inline]
         isolate_freepages mm/compaction.c:1438 [inline]
         compaction_alloc+0x1aee/0x22e0 mm/compaction.c:1550
      
      There is no reproducer and it is difficult to hit -- 1 crash every few
      days.  The issue is very similar to the fix in commit 6b0868c820ff
      ("mm/compaction.c: correct zone boundary handling when resetting pageblock
      skip hints").  When isolating free pages around a target pageblock, the
      boundary handling is off by one and can stray into the next pageblock.
      Triggering the syzbot error requires that the end of pageblock is section
      or zone aligned, and that the next section is unpopulated.
      
      A more subtle consequence of the bug is that pageblocks were being
      improperly used as migration targets which potentially hurts fragmentation
      avoidance in the long-term one page at a time.
      
      A debugging patch revealed that it's definitely possible to stray outside
      of a pageblock which is not intended.  While syzbot cannot be used to
      verify this patch, it was confirmed that the debugging warning no longer
      triggers with this patch applied.  It has also been confirmed that the THP
      allocation stress tests are not degraded by this patch.
      
      Link: http://lkml.kernel.org/r/20190510182124.GI18914@techsingularity.net
      Fixes: e332f741a8dd ("mm, compaction: be selective about what pageblocks to clear skip hints")
      Signed-off-by: NMel Gorman <mgorman@techsingularity.net>
      Reported-by: syzbot+d84c80f9fe26a0f7a734@syzkaller.appspotmail.com
      Cc: Dmitry Vyukov <dvyukov@google.com>
      Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
      Cc: Qian Cai <cai@lca.pw>
      Cc: Michal Hocko <mhocko@suse.com>
      Cc: Vlastimil Babka <vbabka@suse.cz>
      Cc: <stable@vger.kernel.org> # v5.1+
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: NYang Shi <yang.shi@linux.alibaba.com>
      Reviewed-by: NXunlei Pang <xlpang@linux.alibaba.com>
      39470173
    • Q
      mm/compaction.c: fix an undefined behaviour · 00bb2964
      Qian Cai 提交于
      to #26255339
      
      commit dd7ef7bd14640f11763b54f55131000165f48321 upstream
      
      In a low-memory situation, cc->fast_search_fail can keep increasing as it
      is unable to find an available page to isolate in
      fast_isolate_freepages().  As the result, it could trigger an error below,
      so just compare with the maximum bits can be shifted first.
      
      UBSAN: Undefined behaviour in mm/compaction.c:1160:30
      shift exponent 64 is too large for 64-bit type 'unsigned long'
      CPU: 131 PID: 1308 Comm: kcompactd1 Kdump: loaded Tainted: G
      W    L    5.0.0+ #17
      Call trace:
       dump_backtrace+0x0/0x450
       show_stack+0x20/0x2c
       dump_stack+0xc8/0x14c
       __ubsan_handle_shift_out_of_bounds+0x7e8/0x8c4
       compaction_alloc+0x2344/0x2484
       unmap_and_move+0xdc/0x1dbc
       migrate_pages+0x274/0x1310
       compact_zone+0x26ec/0x43bc
       kcompactd+0x15b8/0x1a24
       kthread+0x374/0x390
       ret_from_fork+0x10/0x18
      
      [akpm@linux-foundation.org: code cleanup]
      Link: http://lkml.kernel.org/r/20190320203338.53367-1-cai@lca.pw
      Fixes: 70b44595eafe ("mm, compaction: use free lists to quickly locate a migration source")
      Signed-off-by: NQian Cai <cai@lca.pw>
      Acked-by: NVlastimil Babka <vbabka@suse.cz>
      Acked-by: NMel Gorman <mgorman@techsingularity.net>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: NYang Shi <yang.shi@linux.alibaba.com>
      Reviewed-by: NXunlei Pang <xlpang@linux.alibaba.com>
      00bb2964
    • Q
      mm/compaction.c: abort search if isolation fails · 7f458a1c
      Qian Cai 提交于
      to #26255339
      
      commit 5b56d996dd50a9d2ca87c25ebb50c07b255b7e04 upstream
      
      Running LTP oom01 in a tight loop or memory stress testing put the system
      in a low-memory situation could triggers random memory corruption like
      page flag corruption below due to in fast_isolate_freepages(), if
      isolation fails, next_search_order() does not abort the search immediately
      could lead to improper accesses.
      
      UBSAN: Undefined behaviour in ./include/linux/mm.h:1195:50
      index 7 is out of range for type 'zone [5]'
      Call Trace:
       dump_stack+0x62/0x9a
       ubsan_epilogue+0xd/0x7f
       __ubsan_handle_out_of_bounds+0x14d/0x192
       __isolate_free_page+0x52c/0x600
       compaction_alloc+0x886/0x25f0
       unmap_and_move+0x37/0x1e70
       migrate_pages+0x2ca/0xb20
       compact_zone+0x19cb/0x3620
       kcompactd_do_work+0x2df/0x680
       kcompactd+0x1d8/0x6c0
       kthread+0x32c/0x3f0
       ret_from_fork+0x35/0x40
      ------------[ cut here ]------------
      kernel BUG at mm/page_alloc.c:3124!
      invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN PTI
      RIP: 0010:__isolate_free_page+0x464/0x600
      RSP: 0000:ffff888b9e1af848 EFLAGS: 00010007
      RAX: 0000000030000000 RBX: ffff888c39fcf0f8 RCX: 0000000000000000
      RDX: 1ffff111873f9e25 RSI: 0000000000000004 RDI: ffffed1173c35ef6
      RBP: ffff888b9e1af898 R08: fffffbfff4fc2461 R09: fffffbfff4fc2460
      R10: fffffbfff4fc2460 R11: ffffffffa7e12303 R12: 0000000000000008
      R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000007
      FS:  0000000000000000(0000) GS:ffff888ba8e80000(0000)
      knlGS:0000000000000000
      CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
      CR2: 00007fc7abc00000 CR3: 0000000752416004 CR4: 00000000001606a0
      DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
      DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
      Call Trace:
       compaction_alloc+0x886/0x25f0
       unmap_and_move+0x37/0x1e70
       migrate_pages+0x2ca/0xb20
       compact_zone+0x19cb/0x3620
       kcompactd_do_work+0x2df/0x680
       kcompactd+0x1d8/0x6c0
       kthread+0x32c/0x3f0
       ret_from_fork+0x35/0x40
      
      Link: http://lkml.kernel.org/r/20190320192648.52499-1-cai@lca.pw
      Fixes: dbe2d4e4f12e ("mm, compaction: round-robin the order while searching the free lists for a target")
      Signed-off-by: NQian Cai <cai@lca.pw>
      Acked-by: NMel Gorman <mgorman@techsingularity.net>
      Cc: Daniel Jordan <daniel.m.jordan@oracle.com>
      Cc: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com>
      Cc: Vlastimil Babka <vbabka@suse.cz>
      Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
      Signed-off-by: NMel Gorman <mgorman@techsingularity.net>
      Signed-off-by: NYang Shi <yang.shi@linux.alibaba.com>
      Reviewed-by: NXunlei Pang <xlpang@linux.alibaba.com>
      7f458a1c
    • M
      mm, page_alloc: always use a captured page regardless of compaction result · 19a4cd3c
      Mel Gorman 提交于
      to #26255339
      
      commit ee8ab0eeb49bd3982090c8f14dc9cc65bcd13c5c upstream
      
      During the development of commit 5e1f0f098b46 ("mm, compaction: capture
      a page under direct compaction"), a paranoid check was added to ensure
      that if a captured page was available after compaction that it was
      consistent with the final state of compaction.  The intent was to catch
      serious programming bugs such as using a stale page pointer and causing
      corruption problems.
      
      However, it is possible to get a captured page even if compaction was
      unsuccessful if an interrupt triggered and happened to free pages in
      interrupt context that got merged into a suitable high-order page.  It's
      highly unlikely but Li Wang did report the following warning on s390
      occuring when testing OOM handling.  Note that the warning is slightly
      edited for clarity.
      
        WARNING: CPU: 0 PID: 9783 at mm/page_alloc.c:3777 __alloc_pages_direct_compact+0x182/0x190
        Modules linked in: rpcsec_gss_krb5 auth_rpcgss nfsv4 dns_resolver nfs
          lockd grace fscache sunrpc pkey ghash_s390 prng xts aes_s390
          des_s390 des_generic sha512_s390 zcrypt_cex4 zcrypt vmur binfmt_misc
          ip_tables xfs libcrc32c dasd_fba_mod qeth_l2 dasd_eckd_mod dasd_mod
          qeth qdio lcs ctcm ccwgroup fsm dm_mirror dm_region_hash dm_log
          dm_mod
        CPU: 0 PID: 9783 Comm: copy.sh Kdump: loaded Not tainted 5.1.0-rc 5 #1
      
      This patch simply removes the check entirely instead of trying to be
      clever about pages freed from interrupt context.  If a serious
      programming error was introduced, it is highly likely to be caught by
      prep_new_page() instead.
      
      Link: http://lkml.kernel.org/r/20190419085133.GH18914@techsingularity.net
      Fixes: 5e1f0f098b46 ("mm, compaction: capture a page under direct compaction")
      Signed-off-by: NMel Gorman <mgorman@techsingularity.net>
      Reported-by: NLi Wang <liwang@redhat.com>
      Acked-by: NVlastimil Babka <vbabka@suse.cz>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: NYang Shi <yang.shi@linux.alibaba.com>
      Reviewed-by: NXunlei Pang <xlpang@linux.alibaba.com>
      19a4cd3c
    • M
      mm/compaction.c: correct zone boundary handling when resetting pageblock skip hints · 99d1c410
      Mel Gorman 提交于
      to #26255339
      
      commit 6b0868c820ff7370d15d6ddfe71b1ce6bbe8a25d upstream
      
      Mikhail Gavrilo reported the following bug being triggered in a Fedora
      kernel based on 5.1-rc1 but it is relevant to a vanilla kernel.
      
       kernel: page dumped because: VM_BUG_ON_PAGE(PagePoisoned(p))
       kernel: ------------[ cut here ]------------
       kernel: kernel BUG at include/linux/mm.h:1021!
       kernel: invalid opcode: 0000 [#1] SMP NOPTI
       kernel: CPU: 6 PID: 116 Comm: kswapd0 Tainted: G         C        5.1.0-0.rc1.git1.3.fc31.x86_64 #1
       kernel: Hardware name: System manufacturer System Product Name/ROG STRIX X470-I GAMING, BIOS 1201 12/07/2018
       kernel: RIP: 0010:__reset_isolation_pfn+0x244/0x2b0
       kernel: Code: fe 06 e8 0f 8e fc ff 44 0f b6 4c 24 04 48 85 c0 0f 85 dc fe ff ff e9 68 fe ff ff 48 c7 c6 58 b7 2e 8c 4c 89 ff e8 0c 75 00 00 <0f> 0b 48 c7 c6 58 b7 2e 8c e8 fe 74 00 00 0f 0b 48 89 fa 41 b8 01
       kernel: RSP: 0018:ffff9e2d03f0fde8 EFLAGS: 00010246
       kernel: RAX: 0000000000000034 RBX: 000000000081f380 RCX: ffff8cffbddd6c20
       kernel: RDX: 0000000000000000 RSI: 0000000000000006 RDI: ffff8cffbddd6c20
       kernel: RBP: 0000000000000001 R08: 0000009898b94613 R09: 0000000000000000
       kernel: R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000100000
       kernel: R13: 0000000000100000 R14: 0000000000000001 R15: ffffca7de07ce000
       kernel: FS:  0000000000000000(0000) GS:ffff8cffbdc00000(0000) knlGS:0000000000000000
       kernel: CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
       kernel: CR2: 00007fc1670e9000 CR3: 00000007f5276000 CR4: 00000000003406e0
       kernel: Call Trace:
       kernel:  __reset_isolation_suitable+0x62/0x120
       kernel:  reset_isolation_suitable+0x3b/0x40
       kernel:  kswapd+0x147/0x540
       kernel:  ? finish_wait+0x90/0x90
       kernel:  kthread+0x108/0x140
       kernel:  ? balance_pgdat+0x560/0x560
       kernel:  ? kthread_park+0x90/0x90
       kernel:  ret_from_fork+0x27/0x50
      
      He bisected it down to e332f741a8dd ("mm, compaction: be selective about
      what pageblocks to clear skip hints").  The problem is that the patch in
      question was sloppy with respect to the handling of zone boundaries.  In
      some instances, it was possible for PFNs outside of a zone to be examined
      and if those were not properly initialised or poisoned then it would
      trigger the VM_BUG_ON.  This patch corrects the zone boundary issues when
      resetting pageblock skip hints and Mikhail reported that the bug did not
      trigger after 30 hours of testing.
      
      Link: http://lkml.kernel.org/r/20190327085424.GL3189@techsingularity.net
      Fixes: e332f741a8dd ("mm, compaction: be selective about what pageblocks to clear skip hints")
      Reported-by: NMikhail Gavrilov <mikhail.v.gavrilov@gmail.com>
      Tested-by: NMikhail Gavrilov <mikhail.v.gavrilov@gmail.com>
      Cc: Daniel Jordan <daniel.m.jordan@oracle.com>
      Cc: Qian Cai <cai@lca.pw>
      Cc: Vlastimil Babka <vbabka@suse.cz>
      Signed-off-by: NMel Gorman <mgorman@techsingularity.net>
      Signed-off-by: NYang Shi <yang.shi@linux.alibaba.com>
      Reviewed-by: NXunlei Pang <xlpang@linux.alibaba.com>
      99d1c410
    • M
      mm, compaction: capture a page under direct compaction · 35d915be
      Mel Gorman 提交于
      to #26255339
      
      commit 5e1f0f098b4649fad53011246bcaeff011ffdf5d upstream
      
      Compaction is inherently race-prone as a suitable page freed during
      compaction can be allocated by any parallel task.  This patch uses a
      capture_control structure to isolate a page immediately when it is freed
      by a direct compactor in the slow path of the page allocator.  The
      intent is to avoid redundant scanning.
      
                                           5.0.0-rc1              5.0.0-rc1
                                     selective-v3r17          capture-v3r19
      Amean     fault-both-1         0.00 (   0.00%)        0.00 *   0.00%*
      Amean     fault-both-3      2582.11 (   0.00%)     2563.68 (   0.71%)
      Amean     fault-both-5      4500.26 (   0.00%)     4233.52 (   5.93%)
      Amean     fault-both-7      5819.53 (   0.00%)     6333.65 (  -8.83%)
      Amean     fault-both-12     9321.18 (   0.00%)     9759.38 (  -4.70%)
      Amean     fault-both-18     9782.76 (   0.00%)    10338.76 (  -5.68%)
      Amean     fault-both-24    15272.81 (   0.00%)    13379.55 *  12.40%*
      Amean     fault-both-30    15121.34 (   0.00%)    16158.25 (  -6.86%)
      Amean     fault-both-32    18466.67 (   0.00%)    18971.21 (  -2.73%)
      
      Latency is only moderately affected but the devil is in the details.  A
      closer examination indicates that base page fault latency is reduced but
      latency of huge pages is increased as it takes creater care to succeed.
      Part of the "problem" is that allocation success rates are close to 100%
      even when under pressure and compaction gets harder
      
                                      5.0.0-rc1              5.0.0-rc1
                                selective-v3r17          capture-v3r19
      Percentage huge-3        96.70 (   0.00%)       98.23 (   1.58%)
      Percentage huge-5        96.99 (   0.00%)       95.30 (  -1.75%)
      Percentage huge-7        94.19 (   0.00%)       97.24 (   3.24%)
      Percentage huge-12       94.95 (   0.00%)       97.35 (   2.53%)
      Percentage huge-18       96.74 (   0.00%)       97.30 (   0.58%)
      Percentage huge-24       97.07 (   0.00%)       97.55 (   0.50%)
      Percentage huge-30       95.69 (   0.00%)       98.50 (   2.95%)
      Percentage huge-32       96.70 (   0.00%)       99.27 (   2.65%)
      
      And scan rates are reduced as expected by 6% for the migration scanner
      and 29% for the free scanner indicating that there is less redundant
      work.
      
      Compaction migrate scanned    20815362    19573286
      Compaction free scanned       16352612    11510663
      
      [mgorman@techsingularity.net: remove redundant check]
        Link: http://lkml.kernel.org/r/20190201143853.GH9565@techsingularity.net
      Link: http://lkml.kernel.org/r/20190118175136.31341-23-mgorman@techsingularity.netSigned-off-by: NMel Gorman <mgorman@techsingularity.net>
      Acked-by: NVlastimil Babka <vbabka@suse.cz>
      Cc: Andrea Arcangeli <aarcange@redhat.com>
      Cc: Dan Carpenter <dan.carpenter@oracle.com>
      Cc: David Rientjes <rientjes@google.com>
      Cc: YueHaibing <yuehaibing@huawei.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: NYang Shi <yang.shi@linux.alibaba.com>
      Reviewed-by: NXunlei Pang <xlpang@linux.alibaba.com>
      35d915be
    • M
      mm, compaction: be selective about what pageblocks to clear skip hints · 1edbee61
      Mel Gorman 提交于
      to #26255339
      
      commit e332f741a8dd1ec9a6dc8aa997296ecbfe64323e upstream
      
      Pageblock hints are cleared when compaction restarts or kswapd makes
      enough progress that it can sleep but it's over-eager in that the bit is
      cleared for migration sources with no LRU pages and migration targets
      with no free pages.  As pageblock skip hint flushes are relatively rare
      and out-of-band with respect to kswapd, this patch makes a few more
      expensive checks to see if it's appropriate to even clear the bit.
      Every pageblock that is not cleared will avoid 512 pages being scanned
      unnecessarily on x86-64.
      
      The impact is variable with different workloads showing small
      differences in latency, success rates and scan rates.  This is expected
      as clearing the hints is not that common but doing a small amount of
      work out-of-band to avoid a large amount of work in-band later is
      generally a good thing.
      
      Link: http://lkml.kernel.org/r/20190118175136.31341-22-mgorman@techsingularity.netSigned-off-by: NMel Gorman <mgorman@techsingularity.net>
      Signed-off-by: NQian Cai <cai@lca.pw>
      Acked-by: NVlastimil Babka <vbabka@suse.cz>
      Cc: Andrea Arcangeli <aarcange@redhat.com>
      Cc: Dan Carpenter <dan.carpenter@oracle.com>
      Cc: David Rientjes <rientjes@google.com>
      Cc: YueHaibing <yuehaibing@huawei.com>
      [cai@lca.pw: no stuck in __reset_isolation_pfn()]
        Link: http://lkml.kernel.org/r/20190206034732.75687-1-cai@lca.pwSigned-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: NYang Shi <yang.shi@linux.alibaba.com>
      Reviewed-by: NXunlei Pang <xlpang@linux.alibaba.com>
      1edbee61