• Andreas Herrmann's avatar
    x86: memtest: reuse test patterns when memtest parameter exceeds number of available patterns · 40823f73
    Andreas Herrmann authored
    Impact: fix unexpected behaviour when pattern number is out of range
    
    Current implementation provides 4 patterns for memtest. The code doesn't
    check whether the memtest parameter value exceeds the maximum pattern number.
    
    Instead the memtest code pretends to test with non-existing patterns, e.g.
    when booting with memtest=10 I've observed the following
    
      ...
      early_memtest: pattern num 10
      0000001000 - 0000006000 pattern 0
      ...
      0000001000 - 0000006000 pattern 1
      ...
      0000001000 - 0000006000 pattern 2
      ...
      0000001000 - 0000006000 pattern 3
      ...
      0000001000 - 0000006000 pattern 4
      ...
      0000001000 - 0000006000 pattern 5
      ...
      0000001000 - 0000006000 pattern 6
      ...
      0000001000 - 0000006000 pattern 7
      ...
      0000001000 - 0000006000 pattern 8
      ...
      0000001000 - 0000006000 pattern 9
      ...
    
    But in fact Linux didn't test anything for patterns > 4 as the default
    case in memtest() is to leave the function.
    
    I suggest to use the memtest parameter as the number of tests to be
    performed and to re-iterate over all existing patterns.
    Signed-off-by: default avatarAndreas Herrmann <andreas.herrmann3@amd.com>
    Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
    40823f73
memtest.c 2.7 KB