powerpc: fix e500 SPE float rounding inexactness detection

The e500 SPE floating-point emulation code for the rounding modes
rounding to positive or negative infinity (which may not be
implemented i

powerpc: fix e500 SPE float rounding inexactness detection

The e500 SPE floating-point emulation code for the rounding modes
rounding to positive or negative infinity (which may not be
implemented in hardware) tries to avoid emulating rounding if the
result was inexact. However, it tests inexactness using the sticky
bit with the cumulative result of previous operations, rather than
with the non-sticky bits relating to the operation that generated the
interrupt. Furthermore, when a vector operation generates the
interrupt, it's possible that only one of the low and high parts is
inexact, and so only that part should have rounding emulated. This
results in incorrect rounding of exact results in these modes when the
sticky bit is set from a previous operation.

(I'm not sure why the rounding interrupts are generated at all when
the result is exact, but empirically the hardware does generate them.)

This patch checks for inexactness using the correct bits of SPEFSCR,
and ensures that rounding only occurs when the relevant part of the
result was actually inexact.

Signed-off-by: Joseph Myers <joseph@codesourcery.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>

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powerpc: fix exception clearing in e500 SPE float emulation

The e500 SPE floating-point emulation code clears existing exceptions
(__FPU_FPSCR &= ~FP_EX_MASK;) before ORing in the exceptions from th

powerpc: fix exception clearing in e500 SPE float emulation

The e500 SPE floating-point emulation code clears existing exceptions
(__FPU_FPSCR &= ~FP_EX_MASK;) before ORing in the exceptions from the
emulated operation. However, these exception bits are the "sticky",
cumulative exception bits, and should only be cleared by the user
program setting SPEFSCR, not implicitly by any floating-point
instruction (whether executed purely by the hardware or emulated).
The spurious clearing of these bits shows up as missing exceptions in
glibc testing.

Fixing this, however, is not as simple as just not clearing the bits,
because while the bits may be from previous floating-point operations
(in which case they should not be cleared), the processor can also set
the sticky bits itself before the interrupt for an exception occurs,
and this can happen in cases when IEEE 754 semantics are that the
sticky bit should not be set. Specifically, the "invalid" sticky bit
is set in various cases with non-finite operands, where IEEE 754
semantics do not involve raising such an exception, and the
"underflow" sticky bit is set in cases of exact underflow, whereas
IEEE 754 semantics are that this flag is set only for inexact
underflow. Thus, for correct emulation the kernel needs to know the
setting of these two sticky bits before the instruction being
emulated.

When a floating-point operation raises an exception, the kernel can
note the state of the sticky bits immediately afterwards. Some
<fenv.h> functions that affect the state of these bits, such as
fesetenv and feholdexcept, need to use prctl with PR_GET_FPEXC and
PR_SET_FPEXC anyway, and so it is natural to record the state of those
bits during that call into the kernel and so avoid any need for a
separate call into the kernel to inform it of a change to those bits.
Thus, the interface I chose to use (in this patch and the glibc port)
is that one of those prctl calls must be made after any userspace
change to those sticky bits, other than through a floating-point
operation that traps into the kernel anyway. feclearexcept and
fesetexceptflag duly make those calls, which would not be required
were it not for this issue.

The previous EGLIBC port, and the uClibc code copied from it, is
fundamentally broken as regards any use of prctl for floating-point
exceptions because it didn't use the PR_FP_EXC_SW_ENABLE bit in its
prctl calls (and did various worse things, such as passing a pointer
when prctl expected an integer). If you avoid anything where prctl is
used, the clearing of sticky bits still means it will never give
anything approximating correct exception semantics with existing
kernels. I don't believe the patch makes things any worse for
existing code that doesn't try to inform the kernel of changes to
sticky bits - such code may get incorrect exceptions in some cases,
but it would have done so anyway in other cases.

Signed-off-by: Joseph Myers <joseph@codesourcery.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>

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Merge branch 'next' into for-linus

Merge branches 'hyperv', 'multitouch', 'roccat', 'upstream', 'upstream-fixes', 'wacom' and 'wiimote' into for-linus

Merge branch 'power-supply-scope' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen

Merge remote branch 'wireless-next/master' into ath6kl-next

Conflicts:
drivers/net/wireless/ath/ath6kl/init.c

Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-next into wl12xx-next

Merge commit 'v3.2-rc3' into next

Merge branch 'master' into x86/memblock

Conflicts & resolutions:

* arch/x86/xen/setup.c

dc91c728fd "xen: allow extra memory to be in multiple regions"
24aa07882b "memblock, x86: Replace memblock

Merge branch 'master' into x86/memblock

Conflicts & resolutions:

* arch/x86/xen/setup.c

dc91c728fd "xen: allow extra memory to be in multiple regions"
24aa07882b "memblock, x86: Replace memblock_x86_reserve/free..."

conflicted on xen_add_extra_mem() updates. The resolution is
trivial as the latter just want to replace
memblock_x86_reserve_range() with memblock_reserve().

* drivers/pci/intel-iommu.c

166e9278a3f "x86/ia64: intel-iommu: move to drivers/iommu/"
5dfe8660a3d "bootmem: Replace work_with_active_regions() with..."

conflicted as the former moved the file under drivers/iommu/.
Resolved by applying the chnages from the latter on the moved
file.

* mm/Kconfig

6661672053a "memblock: add NO_BOOTMEM config symbol"
c378ddd53f9 "memblock, x86: Make ARCH_DISCARD_MEMBLOCK a config option"

conflicted trivially. Both added config options. Just
letting both add their own options resolves the conflict.

* mm/memblock.c

d1f0ece6cdc "mm/memblock.c: small function definition fixes"
ed7b56a799c "memblock: Remove memblock_memory_can_coalesce()"

confliected. The former updates function removed by the
latter. Resolution is trivial.

Signed-off-by: Tejun Heo <tj@kernel.org>

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Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-next into wireless-next

Merge tag 'v3.2-rc2' into staging/for_v3.3

* tag 'v3.2-rc2': (3068 commits)
Linux 3.2-rc2
hfs: add sanity check for file name length
fsl-rio: fix compile error
blackfin: Fixup export.h inclu

Merge tag 'v3.2-rc2' into staging/for_v3.3

* tag 'v3.2-rc2': (3068 commits)
Linux 3.2-rc2
hfs: add sanity check for file name length
fsl-rio: fix compile error
blackfin: Fixup export.h includes
Blackfin: add serial TX IRQ in individual platform resource
virtio-pci: fix use after free
ACPI / cpuidle: Remove acpi_idle_suspend (to fix suspend regression)
drm/radeon/kms/combios: fix dynamic allocation of PM clock modes
[CPUFREQ] db8500: fix build error due to undeclared i variable
bma023: Add SFI translation for this device
vrtc: change its year offset from 1960 to 1972
ce4100: fix a build error
arm/imx: fix imx6q mmc error when mounting rootfs
arm/imx: fix AUTO_ZRELADDR selection
arm/imx: fix the references to ARCH_MX3
ARM: mx51/53: set pwm clock parent to ipg_perclk
btrfs: rename the option to nospace_cache
drm/radeon/kms/pm: switch to dynamically allocating clock mode array
drm/radeon/kms: optimize r600_pm_profile_init
drm/radeon/kms/pm: add a proper pm profile init function for fusion
...

Conflicts:
drivers/media/radio/Kconfig

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Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux

Conflicts:
drivers/net/wireless/iwlegacy/iwl-debugfs.c
drivers/net/wireless/iwlegacy/iwl-rx.c
drivers/net/wir

Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux

Conflicts:
drivers/net/wireless/iwlegacy/iwl-debugfs.c
drivers/net/wireless/iwlegacy/iwl-rx.c
drivers/net/wireless/iwlegacy/iwl-scan.c
drivers/net/wireless/iwlegacy/iwl-tx.c
include/net/bluetooth/bluetooth.h

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Merge commit 'v3.2-rc2' into fbdev-next

Merge branch 'master'; commit 'v3.2-rc2' into next

Merge branch 'master' into for-next

Sync with Linus tree to have 157550ff ("mtd: add GPMI-NAND driver
in the config and Makefile") as I have patch depending on that one.

Merge branches 'sh/pm-runtime' and 'common/clkfwk' into sh-fixes-for-linus

Merge branch 'for-3.2' into for-3.3

Merge branch 'fixes-modulesplit' into fixes

Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (106 commits)
powerpc/p3060qds: Add suppor

Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (106 commits)
powerpc/p3060qds: Add support for P3060QDS board
powerpc/83xx: Add shutdown request support to MCU handling on MPC8349 MITX
powerpc/85xx: Make kexec to interate over online cpus
powerpc/fsl_booke: Fix comment in head_fsl_booke.S
powerpc/85xx: issue 15 EOI after core reset for FSL CoreNet devices
powerpc/8xxx: Fix interrupt handling in MPC8xxx GPIO driver
powerpc/85xx: Add 'fsl,pq3-gpio' compatiable for GPIO driver
powerpc/86xx: Correct Gianfar support for GE boards
powerpc/cpm: Clear muram before it is in use.
drivers/virt: add ioctl for 32-bit compat on 64-bit to fsl-hv-manager
powerpc/fsl_msi: add support for "msi-address-64" property
powerpc/85xx: Setup secondary cores PIR with hard SMP id
powerpc/fsl-booke: Fix settlbcam for 64-bit
powerpc/85xx: Adding DCSR node to dtsi device trees
powerpc/85xx: clean up FPGA device tree nodes for Freecsale QorIQ boards
powerpc/85xx: fix PHYS_64BIT selection for P1022DS
powerpc/fsl-booke: Fix setup_initial_memory_limit to not blindly map
powerpc: respect mem= setting for early memory limit setup
powerpc: Update corenet64_smp_defconfig
powerpc: Update mpc85xx/corenet 32-bit defconfigs
...

Fix up trivial conflicts in:
- arch/powerpc/configs/40x/hcu4_defconfig
removed stale file, edited elsewhere
- arch/powerpc/include/asm/udbg.h, arch/powerpc/kernel/udbg.c:
added opal and gelic drivers vs added ePAPR driver
- drivers/tty/serial/8250.c
moved UPIO_TSI to powerpc vs removed UPIO_DWAPB support

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powerpc/math_emu/efp: Look for errata handler when type mismatches

We already have cpu a005 errata handler when instruction cannot be
recognized. Before we lookup the inst, there's type checking, a

powerpc/math_emu/efp: Look for errata handler when type mismatches

We already have cpu a005 errata handler when instruction cannot be
recognized. Before we lookup the inst, there's type checking, and we also
need to handle it in errata handler when the type checking failed.

Signed-off-by: Liu Yu <yu.liu@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

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powerpc/math_emu/efp: No need to round if the result is exact

Signed-off-by: Liu Yu <yu.liu@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

powerpc/math_emu/efp: Use pr_debug instead of printk

Signed-off-by: Liu Yu <yu.liu@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

Merge commit 'v3.1-rc2' into HEAD

Merge branches 'acpica', 'aml-custom', 'bugzilla-16548', 'bugzilla-20242', 'd3-cold', 'ec-asus' and 'thermal-fix' into release

Merge commit 'v2.6.39' into 20110526

Conflicts:
lib/flex_array.c
security/selinux/avc.c
security/selinux/hooks.c
security/selinux/ss/policydb.c
security/smack/smack_lsm.c