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Subject[PULL] uaccess: fix sparse warning on get/put_user for bitwise types
Hello, Arnd,
As you asked, here's a pull request.
This has been in linux-next apparently with no ill effects.

The following changes since commit 99975cc6ada0d5f2675e83abecae05aba5f437d2:

vhost/net: length miscalculation (2015-01-07 12:22:00 +0200)

are available in the git repository at:

git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost.git tags/uaccess_for_upstream

for you to fetch changes up to 0795cb1b46e7938ed679ccd48f933e75272b30e3:

sparc32: nocheck uaccess coding style tweaks (2015-01-13 15:24:14 +0200)

----------------------------------------------------------------
uaccess: fix sparse warning on get/put_user for bitwise types

At the moment, if p and x are both tagged as bitwise types,
some of get_user(x, p), put_user(x, p), __get_user(x, p), __put_user(x, p)
might produce a sparse warning on many architectures.
This is a false positive: *p on these architectures is loaded into long
(typically using asm), then cast back to typeof(*p).

When typeof(*p) is a bitwise type (which is uncommon), such a cast needs
__force, otherwise sparse produces a warning.

Some architectures already have the __force tag, add it
where it's missing.

I verified that adding these __force casts does not supress any useful warnings.

Specifically, vhost wants to read/write bitwise types in userspace memory
using get_user/put_user.
At the moment this triggers sparse errors, since the value is passed through an
integer.

For example:
__le32 __user *p;
__u32 x;

both
put_user(x, p);
and
get_user(x, p);
should be safe, but produce warnings on some architectures.

While there, I noticed that a bunch of architectures violated
coding style rules within uaccess macros.
Included patches to fix them up.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

----------------------------------------------------------------
Michael S. Tsirkin (37):
x86/uaccess: fix sparse errors
alpha/uaccess: fix sparse errors
arm64/uaccess: fix sparse errors
avr32/uaccess: fix sparse errors
blackfin/uaccess: fix sparse errors
cris/uaccess: fix sparse errors
ia64/uaccess: fix sparse errors
m32r/uaccess: fix sparse errors
metag/uaccess: fix sparse errors
openrisc/uaccess: fix sparse errors
parisc/uaccess: fix sparse errors
sh/uaccess: fix sparse errors
sparc32/uaccess: fix sparse errors
sparc64/uaccess: fix sparse errors
m68k/uaccess: fix sparse errors
arm: fix put_user sparse errors
blackfin: fix put_user sparse errors
ia64: fix put_user sparse errors
metag: fix put_user sparse errors
sh: fix put_user sparse errors
avr32: whitespace fix
sparc32: uaccess_32 macro whitespace fixes
sparc64: uaccess_64 macro whitespace fixes
blackfin: macro whitespace fixes
alpha: macro whitespace fixes
arm: macro whitespace fixes
arm64: macro whitespace fixes
avr32: macro whitespace fixes
cris: macro whitespace fixes
frv: macro whitespace fixes
m32r: macro whitespace fixes
m68k: macro whitespace fixes
parisc: macro whitespace fixes
sh: macro whitespace fixes
xtensa: macro whitespace fixes
sparc64: nocheck uaccess coding style tweaks
sparc32: nocheck uaccess coding style tweaks

arch/alpha/include/asm/uaccess.h | 86 ++++-----
arch/arm/include/asm/uaccess.h | 96 +++++-----
arch/arm64/include/asm/uaccess.h | 4 +-
arch/avr32/include/asm/uaccess.h | 24 +--
arch/blackfin/include/asm/uaccess.h | 32 ++--
arch/cris/include/asm/uaccess.h | 117 +++++++------
arch/frv/include/asm/segment.h | 2 +-
arch/ia64/include/asm/uaccess.h | 11 +-
arch/m32r/include/asm/uaccess.h | 88 +++++-----
arch/m68k/include/asm/segment.h | 2 +-
arch/m68k/include/asm/uaccess_mm.h | 40 ++---
arch/metag/include/asm/uaccess.h | 25 +--
arch/openrisc/include/asm/uaccess.h | 4 +-
arch/parisc/include/asm/uaccess.h | 116 ++++++------
arch/sh/include/asm/segment.h | 2 +-
arch/sh/include/asm/uaccess.h | 4 +-
arch/sh/include/asm/uaccess_64.h | 8 +-
arch/sparc/include/asm/uaccess_32.h | 339 +++++++++++++++++++++---------------
arch/sparc/include/asm/uaccess_64.h | 222 ++++++++++++-----------
arch/x86/include/asm/uaccess.h | 2 +-
arch/xtensa/include/asm/uaccess.h | 90 +++++-----
21 files changed, 700 insertions(+), 614 deletions(-)


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