1. 04 Feb, 2020 40 commits
    • Steven Price's avatar
      x86: mm+efi: convert ptdump_walk_pgd_level() to take a mm_struct · e455248d
      Steven Price authored
      To enable x86 to use the generic walk_page_range() function, the callers
      of ptdump_walk_pgd_level() need to pass an mm_struct rather than the raw
      pgd_t pointer.  Luckily since commit 7e904a91 ("efi: Use efi_mm in x86
      as well as ARM") we now have an mm_struct for EFI on x86.
      
      Link: http://lkml.kernel.org/r/20191218162402.45610-18-steven.price@arm.comSigned-off-by: default avatarSteven Price <steven.price@arm.com>
      Cc: Albert Ou <aou@eecs.berkeley.edu>
      Cc: Alexandre Ghiti <alex@ghiti.fr>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
      Cc: Arnd Bergmann <arnd@arndb.de>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Christian Borntraeger <borntraeger@de.ibm.com>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: David S. Miller <davem@davemloft.net>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: James Hogan <jhogan@kernel.org>
      Cc: James Morse <james.morse@arm.com>
      Cc: Jerome Glisse <jglisse@redhat.com>
      Cc: "Liang, Kan" <kan.liang@linux.intel.com>
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: Paul Burton <paul.burton@mips.com>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Paul Walmsley <paul.walmsley@sifive.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: Russell King <linux@armlinux.org.uk>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Vasily Gorbik <gor@linux.ibm.com>
      Cc: Vineet Gupta <vgupta@synopsys.com>
      Cc: Will Deacon <will@kernel.org>
      Cc: Zong Li <zong.li@sifive.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      e455248d
    • Steven Price's avatar
      x86: mm: point to struct seq_file from struct pg_state · 74d2aaa1
      Steven Price authored
      mm/dump_pagetables.c passes both struct seq_file and struct pg_state down
      the chain of walk_*_level() functions to be passed to note_page().
      Instead place the struct seq_file in struct pg_state and access it from
      struct pg_state (which is private to this file) in note_page().
      
      Link: http://lkml.kernel.org/r/20191218162402.45610-17-steven.price@arm.comSigned-off-by: default avatarSteven Price <steven.price@arm.com>
      Cc: Albert Ou <aou@eecs.berkeley.edu>
      Cc: Alexandre Ghiti <alex@ghiti.fr>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
      Cc: Arnd Bergmann <arnd@arndb.de>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Christian Borntraeger <borntraeger@de.ibm.com>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: David S. Miller <davem@davemloft.net>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: James Hogan <jhogan@kernel.org>
      Cc: James Morse <james.morse@arm.com>
      Cc: Jerome Glisse <jglisse@redhat.com>
      Cc: "Liang, Kan" <kan.liang@linux.intel.com>
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: Paul Burton <paul.burton@mips.com>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Paul Walmsley <paul.walmsley@sifive.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: Russell King <linux@armlinux.org.uk>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Vasily Gorbik <gor@linux.ibm.com>
      Cc: Vineet Gupta <vgupta@synopsys.com>
      Cc: Will Deacon <will@kernel.org>
      Cc: Zong Li <zong.li@sifive.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      74d2aaa1
    • Steven Price's avatar
      mm: pagewalk: add 'depth' parameter to pte_hole · b7a16c7a
      Steven Price authored
      The pte_hole() callback is called at multiple levels of the page tables.
      Code dumping the kernel page tables needs to know what at what depth the
      missing entry is.  Add this is an extra parameter to pte_hole().  When the
      depth isn't know (e.g.  processing a vma) then -1 is passed.
      
      The depth that is reported is the actual level where the entry is missing
      (ignoring any folding that is in place), i.e.  any levels where
      PTRS_PER_P?D is set to 1 are ignored.
      
      Note that depth starts at 0 for a PGD so that PUD/PMD/PTE retain their
      natural numbers as levels 2/3/4.
      
      Link: http://lkml.kernel.org/r/20191218162402.45610-16-steven.price@arm.comSigned-off-by: default avatarSteven Price <steven.price@arm.com>
      Tested-by: default avatarZong Li <zong.li@sifive.com>
      Cc: Albert Ou <aou@eecs.berkeley.edu>
      Cc: Alexandre Ghiti <alex@ghiti.fr>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
      Cc: Arnd Bergmann <arnd@arndb.de>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Christian Borntraeger <borntraeger@de.ibm.com>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: David S. Miller <davem@davemloft.net>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: James Hogan <jhogan@kernel.org>
      Cc: James Morse <james.morse@arm.com>
      Cc: Jerome Glisse <jglisse@redhat.com>
      Cc: "Liang, Kan" <kan.liang@linux.intel.com>
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: Paul Burton <paul.burton@mips.com>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Paul Walmsley <paul.walmsley@sifive.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: Russell King <linux@armlinux.org.uk>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Vasily Gorbik <gor@linux.ibm.com>
      Cc: Vineet Gupta <vgupta@synopsys.com>
      Cc: Will Deacon <will@kernel.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      b7a16c7a
    • Steven Price's avatar
      mm: pagewalk: fix termination condition in walk_pte_range() · c02a9875
      Steven Price authored
      If walk_pte_range() is called with a 'end' argument that is beyond the
      last page of memory (e.g.  ~0UL) then the comparison between 'addr' and
      'end' will always fail and the loop will be infinite.  Instead change the
      comparison to >= while accounting for overflow.
      
      Link: http://lkml.kernel.org/r/20191218162402.45610-15-steven.price@arm.comSigned-off-by: default avatarSteven Price <steven.price@arm.com>
      Cc: Albert Ou <aou@eecs.berkeley.edu>
      Cc: Alexandre Ghiti <alex@ghiti.fr>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
      Cc: Arnd Bergmann <arnd@arndb.de>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Christian Borntraeger <borntraeger@de.ibm.com>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: David S. Miller <davem@davemloft.net>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: James Hogan <jhogan@kernel.org>
      Cc: James Morse <james.morse@arm.com>
      Cc: Jerome Glisse <jglisse@redhat.com>
      Cc: "Liang, Kan" <kan.liang@linux.intel.com>
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: Paul Burton <paul.burton@mips.com>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Paul Walmsley <paul.walmsley@sifive.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: Russell King <linux@armlinux.org.uk>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Vasily Gorbik <gor@linux.ibm.com>
      Cc: Vineet Gupta <vgupta@synopsys.com>
      Cc: Will Deacon <will@kernel.org>
      Cc: Zong Li <zong.li@sifive.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      c02a9875
    • Steven Price's avatar
      mm: pagewalk: don't lock PTEs for walk_page_range_novma() · fbf56346
      Steven Price authored
      walk_page_range_novma() can be used to walk page tables or the kernel or
      for firmware.  These page tables may contain entries that are not backed
      by a struct page and so it isn't (in general) possible to take the PTE
      lock for the pte_entry() callback.  So update walk_pte_range() to only
      take the lock when no_vma==false by splitting out the inner loop to a
      separate function and add a comment explaining the difference to
      walk_page_range_novma().
      
      Link: http://lkml.kernel.org/r/20191218162402.45610-14-steven.price@arm.comSigned-off-by: default avatarSteven Price <steven.price@arm.com>
      Cc: Albert Ou <aou@eecs.berkeley.edu>
      Cc: Alexandre Ghiti <alex@ghiti.fr>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
      Cc: Arnd Bergmann <arnd@arndb.de>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Christian Borntraeger <borntraeger@de.ibm.com>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: David S. Miller <davem@davemloft.net>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: James Hogan <jhogan@kernel.org>
      Cc: James Morse <james.morse@arm.com>
      Cc: Jerome Glisse <jglisse@redhat.com>
      Cc: "Liang, Kan" <kan.liang@linux.intel.com>
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: Paul Burton <paul.burton@mips.com>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Paul Walmsley <paul.walmsley@sifive.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: Russell King <linux@armlinux.org.uk>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Vasily Gorbik <gor@linux.ibm.com>
      Cc: Vineet Gupta <vgupta@synopsys.com>
      Cc: Will Deacon <will@kernel.org>
      Cc: Zong Li <zong.li@sifive.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      fbf56346
    • Steven Price's avatar
      mm: pagewalk: allow walking without vma · 488ae6a2
      Steven Price authored
      Since 48684a65: "mm: pagewalk: fix misbehavior of walk_page_range for
      vma(VM_PFNMAP)", page_table_walk() will report any kernel area as a hole,
      because it lacks a vma.
      
      This means each arch has re-implemented page table walking when needed,
      for example in the per-arch ptdump walker.
      
      Remove the requirement to have a vma in the generic code and add a new
      function walk_page_range_novma() which ignores the VMAs and simply walks
      the page tables.
      
      Link: http://lkml.kernel.org/r/20191218162402.45610-13-steven.price@arm.comSigned-off-by: default avatarSteven Price <steven.price@arm.com>
      Cc: Albert Ou <aou@eecs.berkeley.edu>
      Cc: Alexandre Ghiti <alex@ghiti.fr>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
      Cc: Arnd Bergmann <arnd@arndb.de>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Christian Borntraeger <borntraeger@de.ibm.com>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: David S. Miller <davem@davemloft.net>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: James Hogan <jhogan@kernel.org>
      Cc: James Morse <james.morse@arm.com>
      Cc: Jerome Glisse <jglisse@redhat.com>
      Cc: "Liang, Kan" <kan.liang@linux.intel.com>
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: Paul Burton <paul.burton@mips.com>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Paul Walmsley <paul.walmsley@sifive.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: Russell King <linux@armlinux.org.uk>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Vasily Gorbik <gor@linux.ibm.com>
      Cc: Vineet Gupta <vgupta@synopsys.com>
      Cc: Will Deacon <will@kernel.org>
      Cc: Zong Li <zong.li@sifive.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      488ae6a2
    • Steven Price's avatar
      mm: pagewalk: add p4d_entry() and pgd_entry() · 3afc4236
      Steven Price authored
      pgd_entry() and pud_entry() were removed by commit 0b1fbfe5
      ("mm/pagewalk: remove pgd_entry() and pud_entry()") because there were no
      users.  We're about to add users so reintroduce them, along with
      p4d_entry() as we now have 5 levels of tables.
      
      Note that commit a00cc7d9 ("mm, x86: add support for PUD-sized
      transparent hugepages") already re-added pud_entry() but with different
      semantics to the other callbacks.  This commit reverts the semantics back
      to match the other callbacks.
      
      To support hmm.c which now uses the new semantics of pud_entry() a new
      member ('action') of struct mm_walk is added which allows the callbacks to
      either descend (ACTION_SUBTREE, the default), skip (ACTION_CONTINUE) or
      repeat the callback (ACTION_AGAIN).  hmm.c is then updated to call
      pud_trans_huge_lock() itself and make use of the splitting/retry logic of
      the core code.
      
      After this change pud_entry() is called for all entries, not just
      transparent huge pages.
      
      [arnd@arndb.de: fix unused variable warning]
       Link: http://lkml.kernel.org/r/20200107204607.1533842-1-arnd@arndb.de
      Link: http://lkml.kernel.org/r/20191218162402.45610-12-steven.price@arm.comSigned-off-by: default avatarSteven Price <steven.price@arm.com>
      Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
      Cc: Albert Ou <aou@eecs.berkeley.edu>
      Cc: Alexandre Ghiti <alex@ghiti.fr>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
      Cc: Arnd Bergmann <arnd@arndb.de>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Christian Borntraeger <borntraeger@de.ibm.com>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: David S. Miller <davem@davemloft.net>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: James Hogan <jhogan@kernel.org>
      Cc: James Morse <james.morse@arm.com>
      Cc: Jerome Glisse <jglisse@redhat.com>
      Cc: "Liang, Kan" <kan.liang@linux.intel.com>
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: Paul Burton <paul.burton@mips.com>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Paul Walmsley <paul.walmsley@sifive.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: Russell King <linux@armlinux.org.uk>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Vasily Gorbik <gor@linux.ibm.com>
      Cc: Vineet Gupta <vgupta@synopsys.com>
      Cc: Will Deacon <will@kernel.org>
      Cc: Zong Li <zong.li@sifive.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      3afc4236
    • Steven Price's avatar
      x86: mm: add p?d_leaf() definitions · 757b2a4a
      Steven Price authored
      walk_page_range() is going to be allowed to walk page tables other than
      those of user space.  For this it needs to know when it has reached a
      'leaf' entry in the page tables.  This information is provided by the
      p?d_leaf() functions/macros.
      
      For x86 we already have p?d_large() functions, so simply add macros to
      provide the generic p?d_leaf() names for the generic code.
      
      Link: http://lkml.kernel.org/r/20191218162402.45610-11-steven.price@arm.comSigned-off-by: default avatarSteven Price <steven.price@arm.com>
      Cc: Albert Ou <aou@eecs.berkeley.edu>
      Cc: Alexandre Ghiti <alex@ghiti.fr>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
      Cc: Arnd Bergmann <arnd@arndb.de>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Christian Borntraeger <borntraeger@de.ibm.com>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: David S. Miller <davem@davemloft.net>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: James Hogan <jhogan@kernel.org>
      Cc: James Morse <james.morse@arm.com>
      Cc: Jerome Glisse <jglisse@redhat.com>
      Cc: "Liang, Kan" <kan.liang@linux.intel.com>
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: Paul Burton <paul.burton@mips.com>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Paul Walmsley <paul.walmsley@sifive.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: Russell King <linux@armlinux.org.uk>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Vasily Gorbik <gor@linux.ibm.com>
      Cc: Vineet Gupta <vgupta@synopsys.com>
      Cc: Will Deacon <will@kernel.org>
      Cc: Zong Li <zong.li@sifive.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      757b2a4a
    • Steven Price's avatar
      sparc: mm: add p?d_leaf() definitions · 80942493
      Steven Price authored
      walk_page_range() is going to be allowed to walk page tables other than
      those of user space.  For this it needs to know when it has reached a
      'leaf' entry in the page tables.  This information is provided by the
      p?d_leaf() functions/macros.
      
      For sparc 64 bit, pmd_large() and pud_large() are already provided, so add
      macros to provide the p?d_leaf names required by the generic code.
      
      Link: http://lkml.kernel.org/r/20191218162402.45610-10-steven.price@arm.comSigned-off-by: default avatarSteven Price <steven.price@arm.com>
      Acked-by: default avatarDavid S. Miller <davem@davemloft.net>
      Cc: Albert Ou <aou@eecs.berkeley.edu>
      Cc: Alexandre Ghiti <alex@ghiti.fr>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
      Cc: Arnd Bergmann <arnd@arndb.de>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Christian Borntraeger <borntraeger@de.ibm.com>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: James Hogan <jhogan@kernel.org>
      Cc: James Morse <james.morse@arm.com>
      Cc: Jerome Glisse <jglisse@redhat.com>
      Cc: "Liang, Kan" <kan.liang@linux.intel.com>
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: Paul Burton <paul.burton@mips.com>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Paul Walmsley <paul.walmsley@sifive.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: Russell King <linux@armlinux.org.uk>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Vasily Gorbik <gor@linux.ibm.com>
      Cc: Vineet Gupta <vgupta@synopsys.com>
      Cc: Will Deacon <will@kernel.org>
      Cc: Zong Li <zong.li@sifive.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      80942493
    • Steven Price's avatar
      s390: mm: add p?d_leaf() definitions · 8d2109f2
      Steven Price authored
      walk_page_range() is going to be allowed to walk page tables other than
      those of user space.  For this it needs to know when it has reached a
      'leaf' entry in the page tables.  This information is provided by the
      p?d_leaf() functions/macros.
      
      For s390, pud_large() and pmd_large() are already implemented as static
      inline functions.  Add a macro to provide the p?d_leaf names for the
      generic code to use.
      
      Link: http://lkml.kernel.org/r/20191218162402.45610-9-steven.price@arm.comSigned-off-by: default avatarSteven Price <steven.price@arm.com>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: Vasily Gorbik <gor@linux.ibm.com>
      Cc: Christian Borntraeger <borntraeger@de.ibm.com>
      Cc: Albert Ou <aou@eecs.berkeley.edu>
      Cc: Alexandre Ghiti <alex@ghiti.fr>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
      Cc: Arnd Bergmann <arnd@arndb.de>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: David S. Miller <davem@davemloft.net>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: James Hogan <jhogan@kernel.org>
      Cc: James Morse <james.morse@arm.com>
      Cc: Jerome Glisse <jglisse@redhat.com>
      Cc: "Liang, Kan" <kan.liang@linux.intel.com>
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: Paul Burton <paul.burton@mips.com>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Paul Walmsley <paul.walmsley@sifive.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: Russell King <linux@armlinux.org.uk>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Vineet Gupta <vgupta@synopsys.com>
      Cc: Will Deacon <will@kernel.org>
      Cc: Zong Li <zong.li@sifive.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      8d2109f2
    • Steven Price's avatar
      riscv: mm: add p?d_leaf() definitions · af6513ea
      Steven Price authored
      walk_page_range() is going to be allowed to walk page tables other than
      those of user space.  For this it needs to know when it has reached a
      'leaf' entry in the page tables.  This information is provided by the
      p?d_leaf() functions/macros.
      
      For riscv a page is a leaf page when it has a read, write or execute bit
      set on it.
      
      Link: http://lkml.kernel.org/r/20191218162402.45610-8-steven.price@arm.comSigned-off-by: default avatarSteven Price <steven.price@arm.com>
      Reviewed-by: default avatarAlexandre Ghiti <alex@ghiti.fr>
      Reviewed-by: default avatarZong Li <zong.li@sifive.com>
      Acked-by: Paul Walmsley <paul.walmsley@sifive.com>	[arch/riscv]
      Cc: Albert Ou <aou@eecs.berkeley.edu>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
      Cc: Arnd Bergmann <arnd@arndb.de>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Christian Borntraeger <borntraeger@de.ibm.com>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: David S. Miller <davem@davemloft.net>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: James Hogan <jhogan@kernel.org>
      Cc: James Morse <james.morse@arm.com>
      Cc: Jerome Glisse <jglisse@redhat.com>
      Cc: "Liang, Kan" <kan.liang@linux.intel.com>
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: Paul Burton <paul.burton@mips.com>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: Russell King <linux@armlinux.org.uk>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Vasily Gorbik <gor@linux.ibm.com>
      Cc: Vineet Gupta <vgupta@synopsys.com>
      Cc: Will Deacon <will@kernel.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      af6513ea
    • Steven Price's avatar
      powerpc: mm: add p?d_leaf() definitions · 070434b1
      Steven Price authored
      walk_page_range() is going to be allowed to walk page tables other than
      those of user space.  For this it needs to know when it has reached a
      'leaf' entry in the page tables.  This information is provided by the
      p?d_leaf() functions/macros.
      
      For powerpc p?d_is_leaf() functions already exist.  Export them using the
      new p?d_leaf() name.
      
      Link: http://lkml.kernel.org/r/20191218162402.45610-7-steven.price@arm.comSigned-off-by: default avatarSteven Price <steven.price@arm.com>
      Acked-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Albert Ou <aou@eecs.berkeley.edu>
      Cc: Alexandre Ghiti <alex@ghiti.fr>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
      Cc: Arnd Bergmann <arnd@arndb.de>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Christian Borntraeger <borntraeger@de.ibm.com>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: David S. Miller <davem@davemloft.net>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: James Hogan <jhogan@kernel.org>
      Cc: James Morse <james.morse@arm.com>
      Cc: Jerome Glisse <jglisse@redhat.com>
      Cc: "Liang, Kan" <kan.liang@linux.intel.com>
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Paul Burton <paul.burton@mips.com>
      Cc: Paul Walmsley <paul.walmsley@sifive.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: Russell King <linux@armlinux.org.uk>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Vasily Gorbik <gor@linux.ibm.com>
      Cc: Vineet Gupta <vgupta@synopsys.com>
      Cc: Will Deacon <will@kernel.org>
      Cc: Zong Li <zong.li@sifive.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      070434b1
    • Steven Price's avatar
      mips: mm: add p?d_leaf() definitions · 501b8104
      Steven Price authored
      walk_page_range() is going to be allowed to walk page tables other than
      those of user space.  For this it needs to know when it has reached a
      'leaf' entry in the page tables.  This information is provided by the
      p?d_leaf() functions/macros.
      
      If _PAGE_HUGE is defined we can simply look for it.  When not defined we
      can be confident that there are no leaf pages in existence and fall back
      on the generic implementation (added in a later patch) which returns 0.
      
      Link: http://lkml.kernel.org/r/20191218162402.45610-6-steven.price@arm.comSigned-off-by: default avatarSteven Price <steven.price@arm.com>
      Acked-by: default avatarPaul Burton <paul.burton@mips.com>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: Paul Burton <paul.burton@mips.com>
      Cc: James Hogan <jhogan@kernel.org>
      Cc: Albert Ou <aou@eecs.berkeley.edu>
      Cc: Alexandre Ghiti <alex@ghiti.fr>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
      Cc: Arnd Bergmann <arnd@arndb.de>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Christian Borntraeger <borntraeger@de.ibm.com>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: David S. Miller <davem@davemloft.net>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: James Morse <james.morse@arm.com>
      Cc: Jerome Glisse <jglisse@redhat.com>
      Cc: "Liang, Kan" <kan.liang@linux.intel.com>
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Paul Walmsley <paul.walmsley@sifive.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Russell King <linux@armlinux.org.uk>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Vasily Gorbik <gor@linux.ibm.com>
      Cc: Vineet Gupta <vgupta@synopsys.com>
      Cc: Will Deacon <will@kernel.org>
      Cc: Zong Li <zong.li@sifive.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      501b8104
    • Steven Price's avatar
      arm64: mm: add p?d_leaf() definitions · 8aa82df3
      Steven Price authored
      walk_page_range() is going to be allowed to walk page tables other than
      those of user space.  For this it needs to know when it has reached a
      'leaf' entry in the page tables.  This information will be provided by the
      p?d_leaf() functions/macros.
      
      For arm64, we already have p?d_sect() macros which we can reuse for
      p?d_leaf().
      
      pud_sect() is defined as a dummy function when CONFIG_PGTABLE_LEVELS < 3
      or CONFIG_ARM64_64K_PAGES is defined.  However when the kernel is
      configured this way then architecturally it isn't allowed to have a large
      page at this level, and any code using these page walking macros is
      implicitly relying on the page size/number of levels being the same as the
      kernel.  So it is safe to reuse this for p?d_leaf() as it is an
      architectural restriction.
      
      Link: http://lkml.kernel.org/r/20191218162402.45610-5-steven.price@arm.comSigned-off-by: default avatarSteven Price <steven.price@arm.com>
      Acked-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Will Deacon <will@kernel.org>
      Cc: Albert Ou <aou@eecs.berkeley.edu>
      Cc: Alexandre Ghiti <alex@ghiti.fr>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
      Cc: Arnd Bergmann <arnd@arndb.de>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Christian Borntraeger <borntraeger@de.ibm.com>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: David S. Miller <davem@davemloft.net>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: James Hogan <jhogan@kernel.org>
      Cc: James Morse <james.morse@arm.com>
      Cc: Jerome Glisse <jglisse@redhat.com>
      Cc: "Liang, Kan" <kan.liang@linux.intel.com>
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: Paul Burton <paul.burton@mips.com>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Paul Walmsley <paul.walmsley@sifive.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: Russell King <linux@armlinux.org.uk>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Vasily Gorbik <gor@linux.ibm.com>
      Cc: Vineet Gupta <vgupta@synopsys.com>
      Cc: Zong Li <zong.li@sifive.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      8aa82df3
    • Steven Price's avatar
      arm: mm: add p?d_leaf() definitions · 8a0af66b
      Steven Price authored
      walk_page_range() is going to be allowed to walk page tables other than
      those of user space.  For this it needs to know when it has reached a
      'leaf' entry in the page tables.  This information is provided by the
      p?d_leaf() functions/macros.
      
      For arm pmd_large() already exists and does what we want.  So simply
      provide the generic pmd_leaf() name.
      
      Link: http://lkml.kernel.org/r/20191218162402.45610-4-steven.price@arm.comSigned-off-by: default avatarSteven Price <steven.price@arm.com>
      Cc: Russell King <linux@armlinux.org.uk>
      Cc: Albert Ou <aou@eecs.berkeley.edu>
      Cc: Alexandre Ghiti <alex@ghiti.fr>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
      Cc: Arnd Bergmann <arnd@arndb.de>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Christian Borntraeger <borntraeger@de.ibm.com>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: David S. Miller <davem@davemloft.net>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: James Hogan <jhogan@kernel.org>
      Cc: James Morse <james.morse@arm.com>
      Cc: Jerome Glisse <jglisse@redhat.com>
      Cc: "Liang, Kan" <kan.liang@linux.intel.com>
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: Paul Burton <paul.burton@mips.com>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Paul Walmsley <paul.walmsley@sifive.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Vasily Gorbik <gor@linux.ibm.com>
      Cc: Vineet Gupta <vgupta@synopsys.com>
      Cc: Will Deacon <will@kernel.org>
      Cc: Zong Li <zong.li@sifive.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      8a0af66b
    • Steven Price's avatar
      arc: mm: add p?d_leaf() definitions · 4f6b2c08
      Steven Price authored
      walk_page_range() is going to be allowed to walk page tables other than
      those of user space.  For this it needs to know when it has reached a
      'leaf' entry in the page tables.  This information will be provided by the
      p?d_leaf() functions/macros.
      
      For arc, we only have two levels, so only pmd_leaf() is needed.
      
      Link: http://lkml.kernel.org/r/20191218162402.45610-3-steven.price@arm.comSigned-off-by: default avatarSteven Price <steven.price@arm.com>
      Acked-by: default avatarVineet Gupta <vgupta@synopsys.com>
      Cc: Albert Ou <aou@eecs.berkeley.edu>
      Cc: Alexandre Ghiti <alex@ghiti.fr>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
      Cc: Arnd Bergmann <arnd@arndb.de>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Christian Borntraeger <borntraeger@de.ibm.com>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: David S. Miller <davem@davemloft.net>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: James Hogan <jhogan@kernel.org>
      Cc: James Morse <james.morse@arm.com>
      Cc: Jerome Glisse <jglisse@redhat.com>
      Cc: "Liang, Kan" <kan.liang@linux.intel.com>
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: Paul Burton <paul.burton@mips.com>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Paul Walmsley <paul.walmsley@sifive.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: Russell King <linux@armlinux.org.uk>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Vasily Gorbik <gor@linux.ibm.com>
      Cc: Will Deacon <will@kernel.org>
      Cc: Zong Li <zong.li@sifive.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      4f6b2c08
    • Steven Price's avatar
      mm: add generic p?d_leaf() macros · 93fab1b2
      Steven Price authored
      Patch series "Generic page walk and ptdump", v17.
      
      Many architectures current have a debugfs file for dumping the kernel page
      tables.  Currently each architecture has to implement custom functions for
      this because the details of walking the page tables used by the kernel are
      different between architectures.
      
      This series extends the capabilities of walk_page_range() so that it can
      deal with the page tables of the kernel (which have no VMAs and can
      contain larger huge pages than exist for user space).  A generic PTDUMP
      implementation is the implemented making use of the new functionality of
      walk_page_range() and finally arm64 and x86 are switch to using it,
      removing the custom table walkers.
      
      To enable a generic page table walker to walk the unusual mappings of the
      kernel we need to implement a set of functions which let us know when the
      walker has reached the leaf entry.  After a suggestion from Will Deacon
      I've chosen the name p?d_leaf() as this (hopefully) describes the purpose
      (and is a new name so has no historic baggage).  Some architectures have
      p?d_large macros but this is easily confused with "large pages".
      
      This series ends with a generic PTDUMP implemention for arm64 and x86.
      
      Mostly this is a clean up and there should be very little functional
      change.  The exceptions are:
      
      * arm64 PTDUMP debugfs now displays pages which aren't present (patch 22).
      
      * arm64 has the ability to efficiently process KASAN pages (which
        previously only x86 implemented).  This means that the combination of
        KASAN and DEBUG_WX is now useable.
      
      This patch (of 23):
      
      Exposing the pud/pgd levels of the page tables to walk_page_range() means
      we may come across the exotic large mappings that come with large areas of
      contiguous memory (such as the kernel's linear map).
      
      For architectures that don't provide all p?d_leaf() macros, provide
      generic do nothing default that are suitable where there cannot be leaf
      pages at that level.  Futher patches will add implementations for
      individual architectures.
      
      The name p?d_leaf() is chosen to minimize the confusion with existing uses
      of "large" pages and "huge" pages which do not necessary mean that the
      entry is a leaf (for example it may be a set of contiguous entries that
      only take 1 TLB slot).  For the purpose of walking the page tables we
      don't need to know how it will be represented in the TLB, but we do need
      to know for sure if it is a leaf of the tree.
      
      Link: http://lkml.kernel.org/r/20191218162402.45610-2-steven.price@arm.comSigned-off-by: default avatarSteven Price <steven.price@arm.com>
      Acked-by: default avatarMark Rutland <mark.rutland@arm.com>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
      Cc: Arnd Bergmann <arnd@arndb.de>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: James Morse <james.morse@arm.com>
      Cc: Jerome Glisse <jglisse@redhat.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Will Deacon <will@kernel.org>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: "Liang, Kan" <kan.liang@linux.intel.com>
      Cc: Albert Ou <aou@eecs.berkeley.edu>
      Cc: Alexandre Ghiti <alex@ghiti.fr>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Christian Borntraeger <borntraeger@de.ibm.com>
      Cc: David S. Miller <davem@davemloft.net>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: James Hogan <jhogan@kernel.org>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: Paul Burton <paul.burton@mips.com>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Paul Walmsley <paul.walmsley@sifive.com>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: Russell King <linux@armlinux.org.uk>
      Cc: Vasily Gorbik <gor@linux.ibm.com>
      Cc: Vineet Gupta <vgupta@synopsys.com>
      Cc: Zong Li <zong.li@sifive.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      93fab1b2
    • Florian Westphal's avatar
      mm: remove __krealloc · 1c948715
      Florian Westphal authored
      Since 5.5-rc1 the last user of this function is gone, so remove the
      functionality.
      
      See commit
      2ad9d774 ("netfilter: conntrack: free extension area immediately")
      for details.
      
      Link: http://lkml.kernel.org/r/20191212223442.22141-1-fw@strlen.deSigned-off-by: default avatarFlorian Westphal <fw@strlen.de>
      Acked-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Acked-by: default avatarDavid Rientjes <rientjes@google.com>
      Reviewed-by: default avatarDavid Hildenbrand <david@redhat.com>
      Cc: Christoph Lameter <cl@linux.com>
      Cc: Pekka Enberg <penberg@kernel.org>
      Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      1c948715
    • Randy Dunlap's avatar
      pinctrl: fix pxa2xx.c build warnings · 9a8c8b43
      Randy Dunlap authored
      Add #include of <linux/pinctrl/machine.h> to fix build
      warnings in pinctrl-pxa2xx.c.  Fixes these warnings:
      
      In file included from ../drivers/pinctrl/pxa/pinctrl-pxa2xx.c:24:0:
      ../drivers/pinctrl/pxa/../pinctrl-utils.h:36:8: warning: `enum pinctrl_map_type' declared inside parameter list [enabled by default]
         enum pinctrl_map_type type);
              ^
      ../drivers/pinctrl/pxa/../pinctrl-utils.h:36:8: warning: its scope is only this definition or declaration, which is probably not what you want [enabled by default]
      
      Link: http://lkml.kernel.org/r/0024542e-cba9-8f13-6c18-32d0050a6007@infradead.orgSigned-off-by: default avatarRandy Dunlap <rdunlap@infradead.org>
      Cc: Robert Jarzmik <robert.jarzmik@free.fr>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      9a8c8b43
    • Andrew Morton's avatar
      drivers/block/null_blk_main.c: fix uninitialized var warnings · 046755a2
      Andrew Morton authored
      With gcc-7.2, many instances of
      
      drivers/block/null_blk_main.c: In function ‘nullb_device_zone_nr_conv_store’:
      drivers/block/null_blk_main.c:291:12: warning: ‘new_value’ may be used uninitialized in this function [-Wmaybe-uninitialized]
        dev->NAME = new_value;      \
                  ^
      drivers/block/null_blk_main.c:279:7: note: ‘new_value’ was declared here
        TYPE new_value;       \
             ^
      
      Presumably notabug, so use uninitialized_var() to suppress them.
      
      Cc: Shaohua Li <shli@fb.com>
      Cc: Jens Axboe <axboe@kernel.dk>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      046755a2
    • Andrew Morton's avatar
      drivers/block/null_blk_main.c: fix layout · ca0a95a6
      Andrew Morton authored
      Each line here overflows 80 cols by exactly one character.  Delete one tab
      per line to fix.
      
      Cc: Shaohua Li <shli@fb.com>
      Cc: Jens Axboe <axboe@kernel.dk>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      ca0a95a6
    • Lu Shuaibing's avatar
      ipc/msg.c: consolidate all xxxctl_down() functions · 889b3317
      Lu Shuaibing authored
      A use of uninitialized memory in msgctl_down() because msqid64 in
      ksys_msgctl hasn't been initialized.  The local | msqid64 | is created in
      ksys_msgctl() and then passed into msgctl_down().  Along the way msqid64
      is never initialized before msgctl_down() checks msqid64->msg_qbytes.
      
      KUMSAN(KernelUninitializedMemorySantizer, a new error detection tool)
      reports:
      
      ==================================================================
      BUG: KUMSAN: use of uninitialized memory in msgctl_down+0x94/0x300
      Read of size 8 at addr ffff88806bb97eb8 by task syz-executor707/2022
      
      CPU: 0 PID: 2022 Comm: syz-executor707 Not tainted 5.2.0-rc4+ #63
      Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014
      Call Trace:
       dump_stack+0x75/0xae
       __kumsan_report+0x17c/0x3e6
       kumsan_report+0xe/0x20
       msgctl_down+0x94/0x300
       ksys_msgctl.constprop.14+0xef/0x260
       do_syscall_64+0x7e/0x1f0
       entry_SYSCALL_64_after_hwframe+0x44/0xa9
      RIP: 0033:0x4400e9
      Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00
      RSP: 002b:00007ffd869e0598 EFLAGS: 00000246 ORIG_RAX: 0000000000000047
      RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 00000000004400e9
      RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
      RBP: 00000000006ca018 R08: 0000000000000000 R09: 0000000000000000
      R10: 00000000ffffffff R11: 0000000000000246 R12: 0000000000401970
      R13: 0000000000401a00 R14: 0000000000000000 R15: 0000000000000000
      
      The buggy address belongs to the page:
      page:ffffea0001aee5c0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0
      flags: 0x100000000000000()
      raw: 0100000000000000 0000000000000000 ffffffff01ae0101 0000000000000000
      raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
      page dumped because: kumsan: bad access detected
      ==================================================================
      
      Syzkaller reproducer:
      msgctl$IPC_RMID(0x0, 0x0)
      
      C reproducer:
      // autogenerated by syzkaller (https://github.com/google/syzkaller)
      
      int main(void)
      {
        syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0);
        syscall(__NR_msgctl, 0, 0, 0);
        return 0;
      }
      
      [natechancellor@gmail.com: adjust indentation in ksys_msgctl]
        Link: https://github.com/ClangBuiltLinux/linux/issues/829
        Link: http://lkml.kernel.org/r/20191218032932.37479-1-natechancellor@gmail.com
      Link: http://lkml.kernel.org/r/20190613014044.24234-1-shuaibinglu@126.comSigned-off-by: default avatarLu Shuaibing <shuaibinglu@126.com>
      Signed-off-by: default avatarNathan Chancellor <natechancellor@gmail.com>
      Suggested-by: default avatarArnd Bergmann <arnd@arndb.de>
      Cc: Davidlohr Bueso <dave@stgolabs.net>
      Cc: Manfred Spraul <manfred@colorfullife.com>
      Cc: NeilBrown <neilb@suse.com>
      From: Andrew Morton <akpm@linux-foundation.org>
      Subject: drivers/block/null_blk_main.c: fix layout
      
      Each line here overflows 80 cols by exactly one character.  Delete one tab
      per line to fix.
      
      Cc: Shaohua Li <shli@fb.com>
      Cc: Jens Axboe <axboe@kernel.dk>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      889b3317
    • Manfred Spraul's avatar
      ipc/sem.c: document and update memory barriers · 8116b54e
      Manfred Spraul authored
      Document and update the memory barriers in ipc/sem.c:
      
      - Add smp_store_release() to wake_up_sem_queue_prepare() and
        document why it is needed.
      
      - Read q->status using READ_ONCE+smp_acquire__after_ctrl_dep().
        as the pair for the barrier inside wake_up_sem_queue_prepare().
      
      - Add comments to all barriers, and mention the rules in the block
        regarding locking.
      
      - Switch to using wake_q_add_safe().
      
      Link: http://lkml.kernel.org/r/20191020123305.14715-6-manfred@colorfullife.comSigned-off-by: default avatarManfred Spraul <manfred@colorfullife.com>
      Cc: Waiman Long <longman@redhat.com>
      Cc: Davidlohr Bueso <dave@stgolabs.net>
      Cc: <1vier1@web.de>
      Cc: Peter Zijlstra <peterz@infradead.org>
      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>
      8116b54e
    • Manfred Spraul's avatar
      ipc/msg.c: update and document memory barriers · 0d97a82b
      Manfred Spraul authored
      Transfer findings from ipc/mqueue.c:
      
      - A control barrier was missing for the lockless receive case So in
        theory, not yet initialized data may have been copied to user space -
        obviously only for architectures where control barriers are not NOP.
      
      - use smp_store_release().  In theory, the refount may have been
        decreased to 0 already when wake_q_add() tries to get a reference.
      
      Link: http://lkml.kernel.org/r/20191020123305.14715-5-manfred@colorfullife.comSigned-off-by: default avatarManfred Spraul <manfred@colorfullife.com>
      Cc: Waiman Long <longman@redhat.com>
      Cc: Davidlohr Bueso <dave@stgolabs.net>
      Cc: <1vier1@web.de>
      Cc: Peter Zijlstra <peterz@infradead.org>
      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>
      0d97a82b
    • Manfred Spraul's avatar
      ipc/mqueue.c: update/document memory barriers · c5b2cbdb
      Manfred Spraul authored
      Update and document memory barriers for mqueue.c:
      
      - ewp->state is read without any locks, thus READ_ONCE is required.
      
      - add smp_aquire__after_ctrl_dep() after the READ_ONCE, we need
        acquire semantics if the value is STATE_READY.
      
      - use wake_q_add_safe()
      
      - document why __set_current_state() may be used:
        Reading task->state cannot happen before the wake_q_add() call,
        which happens while holding info->lock. Thus the spin_unlock()
        is the RELEASE, and the spin_lock() is the ACQUIRE.
      
      For completeness: there is also a 3 CPU scenario, if the to be woken
      up task is already on another wake_q.
      Then:
      - CPU1: spin_unlock() of the task that goes to sleep is the RELEASE
      - CPU2: the spin_lock() of the waker is the ACQUIRE
      - CPU2: smp_mb__before_atomic inside wake_q_add() is the RELEASE
      - CPU3: smp_mb__after_spinlock() inside try_to_wake_up() is the ACQUIRE
      
      Link: http://lkml.kernel.org/r/20191020123305.14715-4-manfred@colorfullife.comSigned-off-by: default avatarManfred Spraul <manfred@colorfullife.com>
      Reviewed-by: default avatarDavidlohr Bueso <dbueso@suse.de>
      Cc: Waiman Long <longman@redhat.com>
      Cc: <1vier1@web.de>
      Cc: Peter Zijlstra <peterz@infradead.org>
      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>
      c5b2cbdb
    • Davidlohr Bueso's avatar
      ipc/mqueue.c: remove duplicated code · ed29f171
      Davidlohr Bueso authored
      pipelined_send() and pipelined_receive() are identical, so merge them.
      
      [manfred@colorfullife.com: add changelog]
      Link: http://lkml.kernel.org/r/20191020123305.14715-3-manfred@colorfullife.comSigned-off-by: default avatarDavidlohr Bueso <dave@stgolabs.net>
      Signed-off-by: default avatarManfred Spraul <manfred@colorfullife.com>
      Cc: <1vier1@web.de>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Waiman Long <longman@redhat.com>
      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>
      ed29f171
    • Manfred Spraul's avatar
      smp_mb__{before,after}_atomic(): update Documentation · 39323c64
      Manfred Spraul authored
      When adding the _{acquire|release|relaxed}() variants of some atomic
      operations, it was forgotten to update Documentation/memory_barrier.txt:
      
      smp_mb__{before,after}_atomic() is now intended for all RMW operations
      that do not imply a memory barrier.
      
      1)
      	smp_mb__before_atomic();
      	atomic_add();
      
      2)
      	smp_mb__before_atomic();
      	atomic_xchg_relaxed();
      
      3)
      	smp_mb__before_atomic();
      	atomic_fetch_add_relaxed();
      
      Invalid would be:
      	smp_mb__before_atomic();
      	atomic_set();
      
      In addition, the patch splits the long sentence into multiple shorter
      sentences.
      
      Link: http://lkml.kernel.org/r/20191020123305.14715-2-manfred@colorfullife.com
      Fixes: 654672d4 ("locking/atomics: Add _{acquire|release|relaxed}() variants of some atomic operations")
      Signed-off-by: default avatarManfred Spraul <manfred@colorfullife.com>
      Acked-by: default avatarWaiman Long <longman@redhat.com>
      Cc: Davidlohr Bueso <dave@stgolabs.net>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Will Deacon <will.deacon@arm.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: <1vier1@web.de>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      39323c64
    • David Hildenbrand's avatar
      mm/memory_hotplug: drop valid_start/valid_end from test_pages_in_a_zone() · 92917998
      David Hildenbrand authored
      The callers are only interested in the actual zone, they don't care about
      boundaries.  Return the zone instead to simplify.
      
      Link: http://lkml.kernel.org/r/20200110183308.11849-1-david@redhat.comSigned-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: "Rafael J. Wysocki" <rafael@kernel.org>
      Cc: Michal Hocko <mhocko@suse.com>
      Cc: Oscar Salvador <osalvador@suse.de>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      92917998
    • David Hildenbrand's avatar
      mm/memory_hotplug: cleanup __remove_pages() · 52fb87c8
      David Hildenbrand authored
      Let's drop the basically unused section stuff and simplify.
      
      Also, let's use a shorter variant to calculate the number of pages to
      the next section boundary.
      
      Link: http://lkml.kernel.org/r/20191006085646.5768-11-david@redhat.comSigned-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Cc: Oscar Salvador <osalvador@suse.de>
      Cc: Michal Hocko <mhocko@suse.com>
      Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
      Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
      Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: Dan Williams <dan.j.williams@intel.com>
      Cc: Logan Gunthorpe <logang@deltatee.com>
      Cc: Pankaj Gupta <pagupta@redhat.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      52fb87c8
    • David Hildenbrand's avatar
      mm/memory_hotplug: drop local variables in shrink_zone_span() · 5d12071c
      David Hildenbrand authored
      Get rid of the unnecessary local variables.
      
      Link: http://lkml.kernel.org/r/20191006085646.5768-10-david@redhat.comSigned-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
      Cc: Dan Williams <dan.j.williams@intel.com>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: Logan Gunthorpe <logang@deltatee.com>
      Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
      Cc: Michal Hocko <mhocko@suse.com>
      Cc: Oscar Salvador <osalvador@suse.de>
      Cc: Pankaj Gupta <pagupta@redhat.com>
      Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      5d12071c
    • David Hildenbrand's avatar
      mm/memory_hotplug: don't check for "all holes" in shrink_zone_span() · 950b68d9
      David Hildenbrand authored
      If we have holes, the holes will automatically get detected and removed
      once we remove the next bigger/smaller section.  The extra checks can go.
      
      Link: http://lkml.kernel.org/r/20191006085646.5768-9-david@redhat.comSigned-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Cc: Michal Hocko <mhocko@suse.com>
      Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
      Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
      Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: Dan Williams <dan.j.williams@intel.com>
      Cc: Logan Gunthorpe <logang@deltatee.com>
      Cc: Oscar Salvador <osalvador@suse.de>
      Cc: Pankaj Gupta <pagupta@redhat.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      950b68d9
    • David Hildenbrand's avatar
      mm/memory_hotplug: we always have a zone in find_(smallest|biggest)_section_pfn · 9b05158f
      David Hildenbrand authored
      With shrink_pgdat_span() out of the way, we now always have a valid zone.
      
      Link: http://lkml.kernel.org/r/20191006085646.5768-8-david@redhat.comSigned-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Cc: Michal Hocko <mhocko@suse.com>
      Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
      Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
      Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: Dan Williams <dan.j.williams@intel.com>
      Cc: Logan Gunthorpe <logang@deltatee.com>
      Cc: Oscar Salvador <osalvador@suse.de>
      Cc: Pankaj Gupta <pagupta@redhat.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      9b05158f
    • David Hildenbrand's avatar
      mm/memory_hotplug: poison memmap in remove_pfn_range_from_zone() · d33695b1
      David Hildenbrand authored
      Let's poison the pages similar to when adding new memory in
      sparse_add_section().  Also call remove_pfn_range_from_zone() from
      memunmap_pages(), so we can poison the memmap from there as well.
      
      Link: http://lkml.kernel.org/r/20191006085646.5768-7-david@redhat.comSigned-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Cc: Michal Hocko <mhocko@suse.com>
      Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
      Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
      Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: Dan Williams <dan.j.williams@intel.com>
      Cc: Logan Gunthorpe <logang@deltatee.com>
      Cc: Oscar Salvador <osalvador@suse.de>
      Cc: Pankaj Gupta <pagupta@redhat.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      d33695b1
    • Aneesh Kumar K.V's avatar
      mm/memmap_init: update variable name in memmap_init_zone · 1f8d75c1
      Aneesh Kumar K.V authored
      Patch series "mm/memory_hotplug: Shrink zones before removing memory", v6.
      
      This series fixes the access of uninitialized memmaps when shrinking
      zones/nodes and when removing memory.  Also, it contains all fixes for
      crashes that can be triggered when removing certain namespace using
      memunmap_pages() - ZONE_DEVICE, reported by Aneesh.
      
      We stop trying to shrink ZONE_DEVICE, as it's buggy, fixing it would be
      more involved (we don't have SECTION_IS_ONLINE as an indicator), and
      shrinking is only of limited use (set_zone_contiguous() cannot detect the
      ZONE_DEVICE as contiguous).
      
      We continue shrinking !ZONE_DEVICE zones, however, I reduced the amount of
      code to a minimum.  Shrinking is especially necessary to keep
      zone->contiguous set where possible, especially, on memory unplug of DIMMs
      at zone boundaries.
      
      --------------------------------------------------------------------------
      
      Zones are now properly shrunk when offlining memory blocks or when
      onlining failed.  This allows to properly shrink zones on memory unplug
      even if the separate memory blocks of a DIMM were onlined to different
      zones or re-onlined to a different zone after offlining.
      
      Example:
      
      :/# cat /proc/zoneinfo
      Node 1, zone  Movable
              spanned  0
              present  0
              managed  0
      :/# echo "online_movable" > /sys/devices/system/memory/memory41/state
      :/# echo "online_movable" > /sys/devices/system/memory/memory43/state
      :/# cat /proc/zoneinfo
      Node 1, zone  Movable
              spanned  98304
              present  65536
              managed  65536
      :/# echo 0 > /sys/devices/system/memory/memory43/online
      :/# cat /proc/zoneinfo
      Node 1, zone  Movable
              spanned  32768
              present  32768
              managed  32768
      :/# echo 0 > /sys/devices/system/memory/memory41/online
      :/# cat /proc/zoneinfo
      Node 1, zone  Movable
              spanned  0
              present  0
              managed  0
      
      This patch (of 6):
      
      The third argument is actually number of pages.  Change the variable name
      from size to nr_pages to indicate this better.
      
      No functional change in this patch.
      
      Link: http://lkml.kernel.org/r/20191006085646.5768-3-david@redhat.comSigned-off-by: default avatarAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
      Signed-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Reviewed-by: default avatarPankaj Gupta <pagupta@redhat.com>
      Reviewed-by: default avatarDavid Hildenbrand <david@redhat.com>
      Cc: Michal Hocko <mhocko@suse.com>
      Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
      Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
      Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: Dan Williams <dan.j.williams@intel.com>
      Cc: Logan Gunthorpe <logang@deltatee.com>
      Cc: Oscar Salvador <osalvador@suse.de>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      1f8d75c1
    • David Hildenbrand's avatar
      mm: factor out next_present_section_nr() · 4c605881
      David Hildenbrand authored
      Let's move it to the header and use the shorter variant from
      mm/page_alloc.c (the original one will also check
      "__highest_present_section_nr + 1", which is not necessary).  While at
      it, make the section_nr in next_pfn() const.
      
      In next_pfn(), we now return section_nr_to_pfn(-1) instead of -1 once we
      exceed __highest_present_section_nr, which doesn't make a difference in
      the caller as it is big enough (>= all sane end_pfn).
      
      Link: http://lkml.kernel.org/r/20200113144035.10848-3-david@redhat.comSigned-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Acked-by: default avatarKirill A. Shutemov <kirill.shutemov@linux.intel.com>
      Cc: Baoquan He <bhe@redhat.com>
      Cc: Dan Williams <dan.j.williams@intel.com>
      Cc: "Jin, Zhi" <zhi.jin@intel.com>
      Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
      Cc: Mel Gorman <mgorman@suse.de>
      Cc: Michal Hocko <mhocko@kernel.org>
      Cc: Michal Hocko <mhocko@suse.com>
      Cc: Oscar Salvador <osalvador@suse.de>
      Cc: Pavel Tatashin <pasha.tatashin@oracle.com>
      Cc: Vlastimil Babka <vbabka@suse.cz>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      4c605881
    • David Hildenbrand's avatar
      mm/page_alloc: fix and rework pfn handling in memmap_init_zone() · 948c436e
      David Hildenbrand authored
      Let's update the pfn manually whenever we continue the loop.  This makes
      the code easier to read but also less error prone (and we can directly fix
      one issue).
      
      When overlap_memmap_init() returns true, pfn is updated to
      "memblock_region_memory_end_pfn(r)".  So it already points at the *next*
      pfn to process.  Incrementing the pfn another time is wrong, we might
      leave one uninitialized.  I spotted this by inspecting the code, so I have
      no idea if this is relevant in practise (with kernelcore=mirror).
      
      Link: http://lkml.kernel.org/r/20200113144035.10848-2-david@redhat.com
      Fixes: a9a9e77f ("mm: move mirrored memory specific code outside of memmap_init_zone")
      Signed-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Acked-by: default avatarKirill A. Shutemov <kirill.shutemov@linux.intel.com>
      Reviewed-by: default avatarAlexander Duyck <alexander.h.duyck@linux.intel.com>
      Cc: Pavel Tatashin <pasha.tatashin@oracle.com>
      Cc: Michal Hocko <mhocko@kernel.org>
      Cc: Oscar Salvador <osalvador@suse.de>
      Cc: Kirill A. Shutemov <kirill@shutemov.name>
      Cc: Baoquan He <bhe@redhat.com>
      Cc: Dan Williams <dan.j.williams@intel.com>
      Cc: Vlastimil Babka <vbabka@suse.cz>
      Cc: Mel Gorman <mgorman@suse.de>
      Cc: "Jin, Zhi" <zhi.jin@intel.com>
      Cc: Michal Hocko <mhocko@suse.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      948c436e
    • David Hildenbrand's avatar
      mm/page_alloc.c: initialize memmap of unavailable memory directly · 4b094b78
      David Hildenbrand authored
      Let's make sure that all memory holes are actually marked PageReserved(),
      that page_to_pfn() produces reliable results, and that these pages are not
      detected as "mmap" pages due to the mapcount.
      
      E.g., booting a x86-64 QEMU guest with 4160 MB:
      
      [    0.010585] Early memory node ranges
      [    0.010586]   node   0: [mem 0x0000000000001000-0x000000000009efff]
      [    0.010588]   node   0: [mem 0x0000000000100000-0x00000000bffdefff]
      [    0.010589]   node   0: [mem 0x0000000100000000-0x0000000143ffffff]
      
      max_pfn is 0x144000.
      
      Before this change:
      
      [root@localhost ~]# ./page-types -r -a 0x144000,
                   flags      page-count       MB  symbolic-flags                     long-symbolic-flags
      0x0000000000000800           16384       64  ___________M_______________________________        mmap
                   total           16384       64
      
      After this change:
      
      [root@localhost ~]# ./page-types -r -a 0x144000,
                   flags      page-count       MB  symbolic-flags                     long-symbolic-flags
      0x0000000100000000           16384       64  ___________________________r_______________        reserved
                   total           16384       64
      
      IOW, especially the unavailable physical memory ("memory hole") in the
      last section would not get properly marked PageReserved() and is indicated
      to be "mmap" memory.
      
      Drop the trace of that function from include/linux/mm.h - nobody else
      needs it, and rename it accordingly.
      
      Note: The fake zone/node might not be covered by the zone/node span.  This
      is not an urgent issue (for now, we had the same node/zone due to the
      zeroing).  We'll need a clean way to mark memory holes (e.g., using a page
      type PageHole() if possible or a fake ZONE_INVALID) and eventually stop
      marking these memory holes PageReserved().
      
      Link: http://lkml.kernel.org/r/20191211163201.17179-4-david@redhat.comSigned-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Cc: Oscar Salvador <osalvador@suse.de>
      Cc: Michal Hocko <mhocko@kernel.org>
      Cc: Dan Williams <dan.j.williams@intel.com>
      Cc: Alexey Dobriyan <adobriyan@gmail.com>
      Cc: Bob Picco <bob.picco@oracle.com>
      Cc: Daniel Jordan <daniel.m.jordan@oracle.com>
      Cc: Michal Hocko <mhocko@suse.com>
      Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
      Cc: Pavel Tatashin <pasha.tatashin@oracle.com>
      Cc: Stephen Rothwell <sfr@canb.auug.org.au>
      Cc: Steven Sistare <steven.sistare@oracle.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      4b094b78
    • David Hildenbrand's avatar
      fs/proc/page.c: allow inspection of last section and fix end detection · abec749f
      David Hildenbrand authored
      If max_pfn does not fall onto a section boundary, it is possible to
      inspect PFNs up to max_pfn, and PFNs above max_pfn, however, max_pfn
      itself can't be inspected.  We can have a valid (and online) memmap at and
      above max_pfn if max_pfn is not aligned to a section boundary.  The whole
      early section has a memmap and is marked online.  Being able to inspect
      the state of these PFNs is valuable for debugging, especially because
      max_pfn can change on memory hotplug and expose these memmaps.
      
      Also, querying page flags via "./page-types -r -a 0x144001,"
      (tools/vm/page-types.c) inside a x86-64 guest with 4160MB under QEMU
      results in an (almost) endless loop in user space, because the end is not
      detected properly when starting after max_pfn.
      
      Instead, let's allow to inspect all pages in the highest section and
      return 0 directly if we try to access pages above that section.
      
      While at it, check the count before adjusting it, to avoid masking user
      errors.
      
      Link: http://lkml.kernel.org/r/20191211163201.17179-3-david@redhat.comSigned-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Cc: Alexey Dobriyan <adobriyan@gmail.com>
      Cc: Oscar Salvador <osalvador@suse.de>
      Cc: Michal Hocko <mhocko@kernel.org>
      Cc: Stephen Rothwell <sfr@canb.auug.org.au>
      Cc: Bob Picco <bob.picco@oracle.com>
      Cc: Daniel Jordan <daniel.m.jordan@oracle.com>
      Cc: Dan Williams <dan.j.williams@intel.com>
      Cc: Michal Hocko <mhocko@suse.com>
      Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
      Cc: Pavel Tatashin <pasha.tatashin@oracle.com>
      Cc: Steven Sistare <steven.sistare@oracle.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      abec749f
    • David Hildenbrand's avatar
      mm/page_alloc.c: fix uninitialized memmaps on a partially populated last section · e822969c
      David Hildenbrand authored
      Patch series "mm: fix max_pfn not falling on section boundary", v2.
      
      Playing with different memory sizes for a x86-64 guest, I discovered that
      some memmaps (highest section if max_mem does not fall on the section
      boundary) are marked as being valid and online, but contain garbage.  We
      have to properly initialize these memmaps.
      
      Looking at /proc/kpageflags and friends, I found some more issues,
      partially related to this.
      
      This patch (of 3):
      
      If max_pfn is not aligned to a section boundary, we can easily run into
      BUGs.  This can e.g., be triggered on x86-64 under QEMU by specifying a
      memory size that is not a multiple of 128MB (e.g., 4097MB, but also
      4160MB).  I was told that on real HW, we can easily have this scenario
      (esp., one of the main reasons sub-section hotadd of devmem was added).
      
      The issue is, that we have a valid memmap (pfn_valid()) for the whole
      section, and the whole section will be marked "online".
      pfn_to_online_page() will succeed, but the memmap contains garbage.
      
      E.g., doing a "./page-types -r -a 0x144001" when QEMU was started with "-m
      4160M" - (see tools/vm/page-types.c):
      
      [  200.476376] BUG: unable to handle page fault for address: fffffffffffffffe
      [  200.477500] #PF: supervisor read access in kernel mode
      [  200.478334] #PF: error_code(0x0000) - not-present page
      [  200.479076] PGD 59614067 P4D 59614067 PUD 59616067 PMD 0
      [  200.479557] Oops: 0000 [#4] SMP NOPTI
      [  200.479875] CPU: 0 PID: 603 Comm: page-types Tainted: G      D W         5.5.0-rc1-next-20191209 #93
      [  200.480646] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu4
      [  200.481648] RIP: 0010:stable_page_flags+0x4d/0x410
      [  200.482061] Code: f3 ff 41 89 c0 48 b8 00 00 00 00 01 00 00 00 45 84 c0 0f 85 cd 02 00 00 48 8b 53 08 48 8b 2b 48f
      [  200.483644] RSP: 0018:ffffb139401cbe60 EFLAGS: 00010202
      [  200.484091] RAX: fffffffffffffffe RBX: fffffbeec5100040 RCX: 0000000000000000
      [  200.484697] RDX: 0000000000000001 RSI: ffffffff9535c7cd RDI: 0000000000000246
      [  200.485313] RBP: ffffffffffffffff R08: 0000000000000000 R09: 0000000000000000
      [  200.485917] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000144001
      [  200.486523] R13: 00007ffd6ba55f48 R14: 00007ffd6ba55f40 R15: ffffb139401cbf08
      [  200.487130] FS:  00007f68df717580(0000) GS:ffff9ec77fa00000(0000) knlGS:0000000000000000
      [  200.487804] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
      [  200.488295] CR2: fffffffffffffffe CR3: 0000000135d48000 CR4: 00000000000006f0
      [  200.488897] Call Trace:
      [  200.489115]  kpageflags_read+0xe9/0x140
      [  200.489447]  proc_reg_read+0x3c/0x60
      [  200.489755]  vfs_read+0xc2/0x170
      [  200.490037]  ksys_pread64+0x65/0xa0
      [  200.490352]  do_syscall_64+0x5c/0xa0
      [  200.490665]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
      
      But it can be triggered much easier via "cat /proc/kpageflags > /dev/null"
      after cold/hot plugging a DIMM to such a system:
      
      [root@localhost ~]# cat /proc/kpageflags > /dev/null
      [  111.517275] BUG: unable to handle page fault for address: fffffffffffffffe
      [  111.517907] #PF: supervisor read access in kernel mode
      [  111.518333] #PF: error_code(0x0000) - not-present page
      [  111.518771] PGD a240e067 P4D a240e067 PUD a2410067 PMD 0
      
      This patch fixes that by at least zero-ing out that memmap (so e.g.,
      page_to_pfn() will not crash).  Commit 907ec5fc ("mm: zero remaining
      unavailable struct pages") tried to fix a similar issue, but forgot to
      consider this special case.
      
      After this patch, there are still problems to solve.  E.g., not all of
      these pages falling into a memory hole will actually get initialized later
      and set PageReserved - they are only zeroed out - but at least the
      immediate crashes are gone.  A follow-up patch will take care of this.
      
      Link: http://lkml.kernel.org/r/20191211163201.17179-2-david@redhat.com
      Fixes: f7f99100 ("mm: stop zeroing memory during allocation in vmemmap")
      Signed-off-by: default avatarDavid Hildenbrand <david@redhat.com>
      Tested-by: default avatarDaniel Jordan <daniel.m.jordan@oracle.com>
      Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
      Cc: Pavel Tatashin <pasha.tatashin@oracle.com>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Steven Sistare <steven.sistare@oracle.com>
      Cc: Michal Hocko <mhocko@suse.com>
      Cc: Daniel Jordan <daniel.m.jordan@oracle.com>
      Cc: Bob Picco <bob.picco@oracle.com>
      Cc: Oscar Salvador <osalvador@suse.de>
      Cc: Alexey Dobriyan <adobriyan@gmail.com>
      Cc: Dan Williams <dan.j.williams@intel.com>
      Cc: Michal Hocko <mhocko@kernel.org>
      Cc: Stephen Rothwell <sfr@canb.auug.org.au>
      Cc: <stable@vger.kernel.org>	[4.15+]
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      e822969c
    • Gang He's avatar
      ocfs2: fix oops when writing cloned file · 2d797e9f
      Gang He authored
      Writing a cloned file triggers a kernel oops and the user-space command
      process is also killed by the system.  The bug can be reproduced stably
      via:
      
      1) create a file under ocfs2 file system directory.
      
        journalctl -b > aa.txt
      
      2) create a cloned file for this file.
      
        reflink aa.txt bb.txt
      
      3) write the cloned file with dd command.
      
        dd if=/dev/zero of=bb.txt bs=512 count=1 conv=notrunc
      
      The dd command is killed by the kernel, then you can see the oops message
      via dmesg command.
      
      [  463.875404] BUG: kernel NULL pointer dereference, address: 0000000000000028
      [  463.875413] #PF: supervisor read access in kernel mode
      [  463.875416] #PF: error_code(0x0000) - not-present page
      [  463.875418] PGD 0 P4D 0
      [  463.875425] Oops: 0000 [#1] SMP PTI
      [  463.875431] CPU: 1 PID: 2291 Comm: dd Tainted: G           OE     5.3.16-2-default
      [  463.875433] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
      [  463.875500] RIP: 0010:ocfs2_refcount_cow+0xa4/0x5d0 [ocfs2]
      [  463.875505] Code: 06 89 6c 24 38 89 eb f6 44 24 3c 02 74 be 49 8b 47 28
      [  463.875508] RSP: 0018:ffffa2cb409dfce8 EFLAGS: 00010202
      [  463.875512] RAX: ffff8b1ebdca8000 RBX: 0000000000000001 RCX: ffff8b1eb73a9df0
      [  463.875515] RDX: 0000000000056a01 RSI: 0000000000000000 RDI: 0000000000000000
      [  463.875517] RBP: 0000000000000001 R08: ffff8b1eb73a9de0 R09: 0000000000000000
      [  463.875520] R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000
      [  463.875522] R13: ffff8b1eb922f048 R14: 0000000000000000 R15: ffff8b1eb922f048
      [  463.875526] FS:  00007f8f44d15540(0000) GS:ffff8b1ebeb00000(0000) knlGS:0000000000000000
      [  463.875529] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
      [  463.875532] CR2: 0000000000000028 CR3: 000000003c17a000 CR4: 00000000000006e0
      [  463.875546] Call Trace:
      [  463.875596]  ? ocfs2_inode_lock_full_nested+0x18b/0x960 [ocfs2]
      [  463.875648]  ocfs2_file_write_iter+0xaf8/0xc70 [ocfs2]
      [  463.875672]  new_sync_write+0x12d/0x1d0
      [  463.875688]  vfs_write+0xad/0x1a0
      [  463.875697]  ksys_write+0xa1/0xe0
      [  463.875710]  do_syscall_64+0x60/0x1f0
      [  463.875743]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
      [  463.875758] RIP: 0033:0x7f8f4482ed44
      [  463.875762] Code: 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 80 00 00 00
      [  463.875765] RSP: 002b:00007fff300a79d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
      [  463.875769] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f8f4482ed44
      [  463.875771] RDX: 0000000000000200 RSI: 000055f771b5c000 RDI: 0000000000000001
      [  463.875774] RBP: 0000000000000200 R08: 00007f8f44af9c78 R09: 0000000000000003
      [  463.875776] R10: 000000000000089f R11: 0000000000000246 R12: 000055f771b5c000
      [  463.875779] R13: 0000000000000200 R14: 0000000000000000 R15: 000055f771b5c000
      
      This regression problem was introduced by commit e74540b2 ("ocfs2:
      protect extent tree in ocfs2_prepare_inode_for_write()").
      
      Link: http://lkml.kernel.org/r/20200121050153.13290-1-ghe@suse.com
      Fixes: e74540b2 ("ocfs2: protect extent tree in ocfs2_prepare_inode_for_write()").
      Signed-off-by: default avatarGang He <ghe@suse.com>
      Reviewed-by: default avatarJoseph Qi <joseph.qi@linux.alibaba.com>
      Cc: Mark Fasheh <mark@fasheh.com>
      Cc: Joel Becker <jlbec@evilplan.org>
      Cc: Junxiao Bi <junxiao.bi@oracle.com>
      Cc: Changwei Ge <gechangwei@live.cn>
      Cc: Jun Piao <piaojun@huawei.com>
      Cc: <stable@vger.kernel.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      2d797e9f