1. 09 5月, 2013 21 次提交
  2. 08 5月, 2013 9 次提交
  3. 02 5月, 2013 6 次提交
  4. 13 4月, 2013 1 次提交
    • D
      x86-32: Fix possible incomplete TLB invalidate with PAE pagetables · 1de14c3c
      Dave Hansen 提交于
      This patch attempts to fix:
      
      	https://bugzilla.kernel.org/show_bug.cgi?id=56461
      
      The symptom is a crash and messages like this:
      
      	chrome: Corrupted page table at address 34a03000
      	*pdpt = 0000000000000000 *pde = 0000000000000000
      	Bad pagetable: 000f [#1] PREEMPT SMP
      
      Ingo guesses this got introduced by commit 611ae8e3 ("x86/tlb:
      enable tlb flush range support for x86") since that code started to free
      unused pagetables.
      
      On x86-32 PAE kernels, that new code has the potential to free an entire
      PMD page and will clear one of the four page-directory-pointer-table
      (aka pgd_t entries).
      
      The hardware aggressively "caches" these top-level entries and invlpg
      does not actually affect the CPU's copy.  If we clear one we *HAVE* to
      do a full TLB flush, otherwise we might continue using a freed pmd page.
      (note, we do this properly on the population side in pud_populate()).
      
      This patch tracks whenever we clear one of these entries in the 'struct
      mmu_gather', and ensures that we follow up with a full tlb flush.
      
      BTW, I disassembled and checked that:
      
      	if (tlb->fullmm == 0)
      and
      	if (!tlb->fullmm && !tlb->need_flush_all)
      
      generate essentially the same code, so there should be zero impact there
      to the !PAE case.
      Signed-off-by: NDave Hansen <dave.hansen@linux.intel.com>
      Cc: Peter Anvin <hpa@zytor.com>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Artem S Tashkinov <t.artem@mailcity.com>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      1de14c3c
  5. 12 4月, 2013 2 次提交
  6. 11 4月, 2013 1 次提交