[PATCH 00/18] uaccess: fix sparse warning on get_user for bitwise types

[Michael S. Tsirkin]

At the moment, if p and x are both tagged as bitwise types,
get_user(x, p) produces a sparse warning on many architectures.
This is because *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.

Specificlly, vhost wants to read bitwise types from userspace using get_user.
At the moment this triggers sparse errors, since the value is passed through an
integer.

For now, I worked around this by converting vhost code to access_ok +
__get_user, but that's not robust, I'd like to switch to get_user for 3.19.

I tested this on x86 only so far. Since it's just adding __force, should be
trivially safe everywhere?

Please review, and consider for 3.19.

Who can merge this? Arnd?

Michael S. Tsirkin (18):
  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
  microblaze/uaccess: fix sparse errors
  openrisc/uaccess: fix sparse errors
  parisc/uaccess: fix sparse errors
  powerpc/uaccess: fix sparse errors
  sh/uaccess: fix sparse errors
  sparc/uaccess: fix sparse errors
  sparc/uaccess: fix sparse errors
  xtensa/uaccess: fix sparse errors
  m68k/uaccess: fix sparse errors

 arch/alpha/include/asm/uaccess.h      | 4 ++--
 arch/arm64/include/asm/uaccess.h      | 2 +-
 arch/avr32/include/asm/uaccess.h      | 4 ++--
 arch/blackfin/include/asm/uaccess.h   | 2 +-
 arch/cris/include/asm/uaccess.h       | 4 ++--
 arch/ia64/include/asm/uaccess.h       | 2 +-
 arch/m32r/include/asm/uaccess.h       | 4 ++--
 arch/m68k/include/asm/uaccess_mm.h    | 4 ++--
 arch/metag/include/asm/uaccess.h      | 4 ++--
 arch/microblaze/include/asm/uaccess.h | 4 ++--
 arch/openrisc/include/asm/uaccess.h   | 4 ++--
 arch/parisc/include/asm/uaccess.h     | 2 +-
 arch/powerpc/include/asm/uaccess.h    | 6 +++---
 arch/sh/include/asm/uaccess.h         | 4 ++--
 arch/sparc/include/asm/uaccess_32.h   | 8 ++++----
 arch/sparc/include/asm/uaccess_64.h   | 4 ++--
 arch/x86/include/asm/uaccess.h        | 2 +-
 arch/xtensa/include/asm/uaccess.h     | 4 ++--
 18 files changed, 34 insertions(+), 34 deletions(-)

-- 
MST

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