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  1. 20 8月, 2007 2 次提交
  3. 19 8月, 2007 25 次提交
  5. 18 8月, 2007 4 次提交
  7. 17 8月, 2007 5 次提交
    • D
      [MATH-EMU]: Fix underflow exception reporting. · 40584961
      由 David S. Miller 提交于 
      The underflow exception cases were wrong.

This is one weird area of ieee1754 handling in that the underflow
behavior changes based upon whether underflow is enabled in the trap
enable mask of the FPU control register.  As a specific case the Sparc
V9 manual gives us the following description:

--------------------
If UFM = 0:     Underflow occurs if a nonzero result is tiny and a
                loss of accuracy occurs.  Tininess may be detected
                before or after rounding.  Loss of accuracy may be
                either a denormalization loss or an inexact result.

If UFM = 1:     Underflow occurs if a nonzero result is tiny.
                Tininess may be detected before or after rounding.
--------------------

What this amounts to in the packing case is if we go subnormal,
we set underflow if any of the following are true:

1) rounding sets inexact
2) we ended up rounding back up to normal (this is the case where
   we set the exponent to 1 and set the fraction to zero), this
   should set inexact too
3) underflow is set in FPU control register trap-enable mask

The initially discovered example was "DBL_MIN / 16.0" which
incorrectly generated an underflow.  It should not, unless underflow
is set in the trap-enable mask of the FPU csr.

Another example, "0x0.0000000000001p-1022 / 16.0", should signal both
inexact and underflow.  The cpu implementations and ieee1754
literature is very clear about this.  This is case #2 above.

However, if underflow is set in the trap enable mask, only underflow
should be set and reported as a trap.  That is handled properly by the
prioritization logic in

arch/sparc{,64}/math-emu/math.c:record_exception().

Based upon a report and test case from Jakub Jelinek.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      40584961
    • I
      [POWERPC] Fix invalid semicolon after if statement · 2b02d139
      由 Ilpo Järvinen 提交于 
      A similar fix to netfilter from Eric Dumazet inspired me to
look around a bit by using some grep/sed stuff as looking for
this kind of bugs seemed easy to automate.  This is one of them
I found where it looks like this semicolon is not valid.
Signed-off-by: NIlpo Järvinen <ilpo.jarvinen@helsinki.fi>
Acked-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>
      2b02d139
    • D
      [SPARC64]: Create a HWCAP_SPARC_N2 and report it to userspace on Niagara-2. · 8b224b81
      由 David S. Miller 提交于 
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      8b224b81
    • A
      [IA64] Failure to grow RBS · e8c59c0c
      由 Andrew Burgess 提交于 
      There is a bug in the ia64_do_page_fault code that can cause a failure
to grow the register backing store, or any mapping that is marked as
VM_GROWSUP if the mapping is the highest mapped area of memory.

When the address accessed is below the first mapping the previous mapping
is returned as NULL, and this case is handled.  However, when the address
accessed is above the highest mapping the vma returned is NULL, this
case is not handled correctly, and it fails to spot that this access
might require an existing mapping to grow upwards.
Signed-off-by: NAndrew Burgess <andrew@transitive.com>
Signed-off-by: NTony Luck <tony.luck@intel.com>
      e8c59c0c
    • A
      sh: remove extraneous ; on scif_sercon_putc wait loop · 96989d9d
      由 Andy Whitcroft 提交于 
      It seems we have gained an extraneous trailing ';' on one of the
wait loops in scif_sercon_putc().  Although this is completely
benign as the apparent payload is also the empty statement, it
invites error in the future.  Clean it up now.
Signed-off-by: NAndy Whitcroft <apw@shadowen.org>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>
      96989d9d
  9. 16 8月, 2007 4 次提交