1. 23 3月, 2017 1 次提交
  2. 17 3月, 2017 1 次提交
    • A
      mm, x86: fix native_pud_clear build error · d0f33ac9
      Arnd Bergmann 提交于
      We still get a build error in random configurations, after this has been
      modified a few times:
      
        In file included from include/linux/mm.h:68:0,
                         from include/linux/suspend.h:8,
                         from arch/x86/kernel/asm-offsets.c:12:
        arch/x86/include/asm/pgtable.h:66:26: error: redefinition of 'native_pud_clear'
         #define pud_clear(pud)   native_pud_clear(pud)
      
      My interpretation is that the build error comes from a typo in
      __PAGETABLE_PUD_FOLDED, so fix that typo now, and remove the incorrect
      #ifdef around the native_pud_clear definition.
      
      Fixes: 3e761a42 ("mm, x86: fix HIGHMEM64 && PARAVIRT build config for native_pud_clear()")
      Fixes: a00cc7d9 ("mm, x86: add support for PUD-sized transparent hugepages")
      Link: http://lkml.kernel.org/r/20170314121330.182155-1-arnd@arndb.deSigned-off-by: NArnd Bergmann <arnd@arndb.de>
      Ackedy-by: NDave Jiang <dave.jiang@intel.com>
      Cc: Matthew Wilcox <mawilcox@microsoft.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: Thomas Garnier <thgarnie@google.com>
      Cc: Kees Cook <keescook@chromium.org>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: Hugh Dickins <hughd@google.com>
      Cc: Borislav Petkov <bp@suse.de>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      d0f33ac9
  3. 15 3月, 2017 1 次提交
    • A
      mm, x86: Fix native_pud_clear build error · d434936e
      Arnd Bergmann 提交于
      We still get a build error in random configurations, after this has been
      modified a few times:
      
      In file included from include/linux/mm.h:68:0,
                       from include/linux/suspend.h:8,
                       from arch/x86/kernel/asm-offsets.c:12:
      arch/x86/include/asm/pgtable.h:66:26: error: redefinition of 'native_pud_clear'
       #define pud_clear(pud)   native_pud_clear(pud)
      
      My interpretation is that the build error comes from a typo in __PAGETABLE_PUD_FOLDED,
      so fix that typo now, and remove the incorrect #ifdef around the native_pud_clear
      definition.
      
      Fixes: 3e761a42 ("mm, x86: fix HIGHMEM64 && PARAVIRT build config for native_pud_clear()")
      Fixes: a00cc7d9 ("mm, x86: add support for PUD-sized transparent hugepages")
      Signed-off-by: NArnd Bergmann <arnd@arndb.de>
      Acked-by: NDave Jiang <dave.jiang@intel.com>
      Cc: Kees Cook <keescook@chromium.org>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: Hugh Dickins <hughd@google.com>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Borislav Petkov <bp@suse.de>
      Cc: Thomas Garnier <thgarnie@google.com>
      Link: http://lkml.kernel.org/r/20170314121330.182155-1-arnd@arndb.deSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
      d434936e
  4. 12 3月, 2017 1 次提交
    • D
      x86/tlb: Fix tlb flushing when lguest clears PGE · 2c4ea6e2
      Daniel Borkmann 提交于
      Fengguang reported random corruptions from various locations on x86-32
      after commits d2852a22 ("arch: add ARCH_HAS_SET_MEMORY config") and
      9d876e79 ("bpf: fix unlocking of jited image when module ronx not set")
      that uses the former. While x86-32 doesn't have a JIT like x86_64, the
      bpf_prog_lock_ro() and bpf_prog_unlock_ro() got enabled due to
      ARCH_HAS_SET_MEMORY, whereas Fengguang's test kernel doesn't have module
      support built in and therefore never had the DEBUG_SET_MODULE_RONX setting
      enabled.
      
      After investigating the crashes further, it turned out that using
      set_memory_ro() and set_memory_rw() didn't have the desired effect, for
      example, setting the pages as read-only on x86-32 would still let
      probe_kernel_write() succeed without error. This behavior would manifest
      itself in situations where the vmalloc'ed buffer was accessed prior to
      set_memory_*() such as in case of bpf_prog_alloc(). In cases where it
      wasn't, the page attribute changes seemed to have taken effect, leading to
      the conclusion that a TLB invalidate didn't happen. Moreover, it turned out
      that this issue reproduced with qemu in "-cpu kvm64" mode, but not for
      "-cpu host". When the issue occurs, change_page_attr_set_clr() did trigger
      a TLB flush as expected via __flush_tlb_all() through cpa_flush_range(),
      though.
      
      There are 3 variants for issuing a TLB flush: invpcid_flush_all() (depends
      on CPU feature bits X86_FEATURE_INVPCID, X86_FEATURE_PGE), cr4 based flush
      (depends on X86_FEATURE_PGE), and cr3 based flush.  For "-cpu host" case in
      my setup, the flush used invpcid_flush_all() variant, whereas for "-cpu
      kvm64", the flush was cr4 based. Switching the kvm64 case to cr3 manually
      worked fine, and further investigating the cr4 one turned out that
      X86_CR4_PGE bit was not set in cr4 register, meaning the
      __native_flush_tlb_global_irq_disabled() wrote cr4 twice with the same
      value instead of clearing X86_CR4_PGE in the first write to trigger the
      flush.
      
      It turned out that X86_CR4_PGE was cleared from cr4 during init from
      lguest_arch_host_init() via adjust_pge(). The X86_FEATURE_PGE bit is also
      cleared from there due to concerns of using PGE in guest kernel that can
      lead to hard to trace bugs (see bff672e6 ("lguest: documentation V:
      Host") in init()). The CPU feature bits are cleared in dynamic
      boot_cpu_data, but they never propagated to __flush_tlb_all() as it uses
      static_cpu_has() instead of boot_cpu_has() for testing which variant of TLB
      flushing to use, meaning they still used the old setting of the host
      kernel.
      
      Clearing via setup_clear_cpu_cap(X86_FEATURE_PGE) so this would propagate
      to static_cpu_has() checks is too late at this point as sections have been
      patched already, so for now, it seems reasonable to switch back to
      boot_cpu_has(X86_FEATURE_PGE) as it was prior to commit c109bf95
      ("x86/cpufeature: Remove cpu_has_pge"). This lets the TLB flush trigger via
      cr3 as originally intended, properly makes the new page attributes visible
      and thus fixes the crashes seen by Fengguang.
      
      Fixes: c109bf95 ("x86/cpufeature: Remove cpu_has_pge")
      Reported-by: NFengguang Wu <fengguang.wu@intel.com>
      Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
      Cc: bp@suse.de
      Cc: Kees Cook <keescook@chromium.org>
      Cc: "David S. Miller" <davem@davemloft.net>
      Cc: netdev@vger.kernel.org
      Cc: Rusty Russell <rusty@rustcorp.com.au>
      Cc: Alexei Starovoitov <ast@kernel.org>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: lkp@01.org
      Cc: Laura Abbott <labbott@redhat.com>
      Cc: stable@vger.kernel.org
      Link: http://lkml.kernrl.org/r/20170301125426.l4nf65rx4wahohyl@wfg-t540p.sh.intel.com
      Link: http://lkml.kernel.org/r/25c41ad9eca164be4db9ad84f768965b7eb19d9e.1489191673.git.daniel@iogearbox.netSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
      2c4ea6e2
  5. 11 3月, 2017 1 次提交
    • T
      kexec, x86/purgatory: Unbreak it and clean it up · 40c50c1f
      Thomas Gleixner 提交于
      The purgatory code defines global variables which are referenced via a
      symbol lookup in the kexec code (core and arch).
      
      A recent commit addressing sparse warnings made these static and thereby
      broke kexec_file.
      
      Why did this happen? Simply because the whole machinery is undocumented and
      lacks any form of forward declarations. The variable names are unspecific
      and lack a prefix, so adding forward declarations creates shadow variables
      in the core code. Aside of that the code relies on magic constants and
      duplicate struct definitions with no way to ensure that these things stay
      in sync. The section placement of the purgatory variables happened by
      chance and not by design.
      
      Unbreak kexec and cleanup the mess:
      
       - Add proper forward declarations and document the usage
       - Use common struct definition
       - Use the proper common defines instead of magic constants
       - Add a purgatory_ prefix to have a proper name space
       - Use ARRAY_SIZE() instead of a homebrewn reimplementation
       - Add proper sections to the purgatory variables [ From Mike ]
      
      Fixes: 72042a8c ("x86/purgatory: Make functions and variables static")
      Reported-by: NMike Galbraith <&lt;efault@gmx.de>
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      Cc: Nicholas Mc Guire <der.herr@hofr.at>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Vivek Goyal <vgoyal@redhat.com>
      Cc: "Tobin C. Harding" <me@tobin.cc>
      Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1703101315140.3681@nanosSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
      40c50c1f
  6. 10 3月, 2017 2 次提交
  7. 03 3月, 2017 1 次提交
  8. 02 3月, 2017 4 次提交
  9. 01 3月, 2017 8 次提交
  10. 28 2月, 2017 4 次提交
  11. 25 2月, 2017 2 次提交
  12. 21 2月, 2017 4 次提交
  13. 17 2月, 2017 1 次提交
  14. 16 2月, 2017 1 次提交
  15. 15 2月, 2017 2 次提交
  16. 10 2月, 2017 2 次提交
  17. 09 2月, 2017 1 次提交
  18. 08 2月, 2017 1 次提交
  19. 07 2月, 2017 2 次提交