1. 07 Jan, 2018 6 commits
  2. 06 Jan, 2018 6 commits
  3. 05 Jan, 2018 25 commits
  4. 04 Jan, 2018 3 commits
    • Thomas Gleixner's avatar
      x86/tlb: Drop the _GPL from the cpu_tlbstate export · 1e547681
      Thomas Gleixner authored
      The recent changes for PTI touch cpu_tlbstate from various tlb_flush
      inlines. cpu_tlbstate is exported as GPL symbol, so this causes a
      regression when building out of tree drivers for certain graphics cards.
      
      Aside of that the export was wrong since it was introduced as it should
      have been EXPORT_PER_CPU_SYMBOL_GPL().
      
      Use the correct PER_CPU export and drop the _GPL to restore the previous
      state which allows users to utilize the cards they payed for.
      
      As always I'm really thrilled to make this kind of change to support the
      #friends (or however the hot hashtag of today is spelled) from that closet
      sauce graphics corp.
      
      Fixes: 1e02ce4c ("x86: Store a per-cpu shadow copy of CR4")
      Fixes: 6fd166aa ("x86/mm: Use/Fix PCID to optimize user/kernel switches")
      Reported-by: default avatarKees Cook <keescook@google.com>
      Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: stable@vger.kernel.org
      1e547681
    • Peter Zijlstra's avatar
      x86/events/intel/ds: Use the proper cache flush method for mapping ds buffers · 42f3bdc5
      Peter Zijlstra authored
      Thomas reported the following warning:
      
       BUG: using smp_processor_id() in preemptible [00000000] code: ovsdb-server/4498
       caller is native_flush_tlb_single+0x57/0xc0
       native_flush_tlb_single+0x57/0xc0
       __set_pte_vaddr+0x2d/0x40
       set_pte_vaddr+0x2f/0x40
       cea_set_pte+0x30/0x40
       ds_update_cea.constprop.4+0x4d/0x70
       reserve_ds_buffers+0x159/0x410
       x86_reserve_hardware+0x150/0x160
       x86_pmu_event_init+0x3e/0x1f0
       perf_try_init_event+0x69/0x80
       perf_event_alloc+0x652/0x740
       SyS_perf_event_open+0x3f6/0xd60
       do_syscall_64+0x5c/0x190
      
      set_pte_vaddr is used to map the ds buffers into the cpu entry area, but
      there are two problems with that:
      
       1) The resulting flush is not supposed to be called in preemptible context
      
       2) The cpu entry area is supposed to be per CPU, but the debug store
          buffers are mapped for all CPUs so these mappings need to be flushed
          globally.
      
      Add the necessary preemption protection across the mapping code and flush
      TLBs globally.
      
      Fixes: c1961a46 ("x86/events/intel/ds: Map debug buffers in cpu_entry_area")
      Reported-by: default avatarThomas Zeitlhofer <thomas.zeitlhofer+lkml@ze-it.at>
      Signed-off-by: default avatarPeter Zijlstra <peterz@infradead.org>
      Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
      Tested-by: default avatarThomas Zeitlhofer <thomas.zeitlhofer+lkml@ze-it.at>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: Hugh Dickins <hughd@google.com>
      Cc: stable@vger.kernel.org
      Link: https://lkml.kernel.org/r/20180104170712.GB3040@hirez.programming.kicks-ass.net
      42f3bdc5
    • Thomas Gleixner's avatar
      x86/kaslr: Fix the vaddr_end mess · 1dddd251
      Thomas Gleixner authored
      vaddr_end for KASLR is only documented in the KASLR code itself and is
      adjusted depending on config options. So it's not surprising that a change
      of the memory layout causes KASLR to have the wrong vaddr_end. This can map
      arbitrary stuff into other areas causing hard to understand problems.
      
      Remove the whole ifdef magic and define the start of the cpu_entry_area to
      be the end of the KASLR vaddr range.
      
      Add documentation to that effect.
      
      Fixes: 92a0f81d ("x86/cpu_entry_area: Move it out of the fixmap")
      Reported-by: default avatarBenjamin Gilbert <benjamin.gilbert@coreos.com>
      Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
      Tested-by: default avatarBenjamin Gilbert <benjamin.gilbert@coreos.com>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: stable <stable@vger.kernel.org>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Garnier <thgarnie@google.com>,
      Cc: Alexander Kuleshov <kuleshovmail@gmail.com>
      Link: https://lkml.kernel.org/r/alpine.DEB.2.20.1801041320360.1771@nanos
      1dddd251