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  1. Aug 19, 2007
  3. Aug 18, 2007
  5. Aug 17, 2007
    • David S. Miller's avatar
      [MATH-EMU]: Fix underflow exception reporting. · 40584961
      David S. Miller authored 
      

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: default avatarDavid S. Miller <davem@davemloft.net>
      40584961
    • Ilpo Järvinen's avatar
      [POWERPC] Fix invalid semicolon after if statement · 2b02d139
      Ilpo Järvinen authored 
      

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: default avatarIlpo Järvinen <ilpo.jarvinen@helsinki.fi>
Acked-by: default avatarBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: default avatarPaul Mackerras <paulus@samba.org>
      2b02d139
    • David S. Miller's avatar
      [SPARC64]: Create a HWCAP_SPARC_N2 and report it to userspace on Niagara-2. · 8b224b81
      David S. Miller authored 
      

Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      8b224b81
    • Andrew Burgess's avatar
      [IA64] Failure to grow RBS · e8c59c0c
      Andrew Burgess authored 
      

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: default avatarAndrew Burgess <andrew@transitive.com>
Signed-off-by: default avatarTony Luck <tony.luck@intel.com>
      e8c59c0c
    • Andy Whitcroft's avatar
      sh: remove extraneous ; on scif_sercon_putc wait loop · 96989d9d
      Andy Whitcroft authored 
      

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: default avatarAndy Whitcroft <apw@shadowen.org>
Signed-off-by: default avatarPaul Mundt <lethal@linux-sh.org>
      96989d9d
  7. Aug 16, 2007
  9. Aug 15, 2007
    • Haavard Skinnemoen's avatar
      [AVR32] Define mmiowb() · cca67164
      Haavard Skinnemoen authored 
      

Add empty definition of mmiowb() since some drivers need it. Uncached
writes are strongly ordered on AVR32. They may be delayed if the
dcache is busy doing a writeback, but AFAICT that's not what this
macro is supposed to deal with, at least on UP systems.

We might have to revisit this definition when a SMP-capable AVR32 CPU
comes along, depending on how the busses and cache coherency stuff
end up being implemented.

Signed-off-by: default avatarHaavard Skinnemoen <hskinnemoen@atmel.com>
      cca67164
    • Haavard Skinnemoen's avatar
      [AVR32] Fix bogus pte_page() definition · 6f834197
      Haavard Skinnemoen authored 
      

The current definition of pte_page() masks out valid bits from the
physical address, causing vmalloc_to_page() to misbehave. This may
lead to everything from mmap() silently accessing the wrong data to
"invalid pte" errors dumped by the kernel.

Also remove the now-unused definition of PTE_PHYS_MASK.

Thanks to Matteo Vit for discovering this bug.

Signed-off-by: default avatarHaavard Skinnemoen <hskinnemoen@atmel.com>
      6f834197