1. 26 Feb, 2009 2 commits
    • Mark Nelson's avatar
      powerpc: Fix 64bit memcpy() regression · e423b9ec
      Mark Nelson authored
      This fixes a regression introduced by commit
      25d6e2d7 ("powerpc: Update 64bit memcpy()
      using CPU_FTR_UNALIGNED_LD_STD").
      
      This commit allowed CPUs that have the CPU_FTR_UNALIGNED_LD_STD CPU
      feature bit present to do the memcpy() with unaligned load doubles. But,
      along with this came a bug where our final load double would read bytes
      beyond a page boundary and into the next (unmapped) page. This was caught
      by enabling CONFIG_DEBUG_PAGEALLOC,
      
      The fix was to read only the number of bytes that we need to store rather
      than reading a full 8-byte doubleword and storing only a portion of that.
      
      In order to minimise the amount of existing code touched we use the
      original do_tail for the src_unaligned case.
      
      Below is an example of the regression, as reported by Sachin Sant:
      
      Unable to handle kernel paging request for data at address 0xc00000003f380000
      Faulting instruction address: 0xc000000000039574
      cpu 0x1: Vector: 300 (Data Access) at [c00000003baf3020]
          pc: c000000000039574: .memcpy+0x74/0x244
          lr: d00000000244916c: .ext3_xattr_get+0x288/0x2f4 [ext3]
          sp: c00000003baf32a0
         msr: 8000000000009032
         dar: c00000003f380000
       dsisr: 40000000
        current = 0xc00000003e54b010
        paca    = 0xc000000000a53680
          pid   = 1840, comm = readahead
      enter ? for help
      [link register   ] d00000000244916c .ext3_xattr_get+0x288/0x2f4 [ext3]
      [c00000003baf32a0] d000000002449104 .ext3_xattr_get+0x220/0x2f4 [ext3]
      (unreliab
      le)
      [c00000003baf3390] d00000000244a6e8 .ext3_xattr_security_get+0x40/0x5c [ext3]
      [c00000003baf3400] c000000000148154 .generic_getxattr+0x74/0x9c
      [c00000003baf34a0] c000000000333400 .inode_doinit_with_dentry+0x1c4/0x678
      [c00000003baf3560] c00000000032c6b0 .security_d_instantiate+0x50/0x68
      [c00000003baf35e0] c00000000013c818 .d_instantiate+0x78/0x9c
      [c00000003baf3680] c00000000013ced0 .d_splice_alias+0xf0/0x120
      [c00000003baf3720] d00000000243e05c .ext3_lookup+0xec/0x134 [ext3]
      [c00000003baf37c0] c000000000131e74 .do_lookup+0x110/0x260
      [c00000003baf3880] c000000000134ed0 .__link_path_walk+0xa98/0x1010
      [c00000003baf3970] c0000000001354a0 .path_walk+0x58/0xc4
      [c00000003baf3a20] c000000000135720 .do_path_lookup+0x138/0x1e4
      [c00000003baf3ad0] c00000000013645c .path_lookup_open+0x6c/0xc8
      [c00000003baf3b70] c000000000136780 .do_filp_open+0xcc/0x874
      [c00000003baf3d10] c0000000001251e0 .do_sys_open+0x80/0x140
      [c00000003baf3dc0] c00000000016aaec .compat_sys_open+0x24/0x38
      [c00000003baf3e30] c00000000000855c syscall_exit+0x0/0x40
      Signed-off-by: default avatarBenjamin Herrenschmidt <benh@kernel.crashing.org>
      e423b9ec
    • Michael Neuling's avatar
      powerpc: Fix load/store float double alignment handler · 49f297f8
      Michael Neuling authored
      When we introduced VSX, we changed the way FPRs are stored in the
      thread_struct.  Unfortunately we missed the load/store float double
      alignment handler code when updating how we access FPRs in the
      thread_struct.
      
      Below fixes this and merges the little/big endian case.
      Signed-off-by: default avatarMichael Neuling <mikey@neuling.org>
      Signed-off-by: default avatarBenjamin Herrenschmidt <benh@kernel.crashing.org>
      49f297f8
  2. 25 Feb, 2009 37 commits
  3. 24 Feb, 2009 1 commit