[PATCH v2 00/40] uaccess: fix sparse warning on get/put_user for bitwise types
From: Michael S. Tsirkin
Date: Tue Jan 06 2015 - 10:43:45 EST
changes from v1:
- xtensa and powerpc patches have been merged by maintainers, drop them
- added patches to fix put_user on a bunch of architectures
- add acks received since v1
- a bunch of whitespace tweaks
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)
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.
Added patches to fix them up.
I tested this on x86 only. Since it's just adding __force, should be
trivially safe everywhere?
Arnd, did you merge v1 already? If yes, can you please replace with
this version?
Michael S. Tsirkin (40):
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
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
tile: fix put_user sparse errors
tile: enable sparse checks for get/put_user
avr32: whitespace fix
arch/sparc: uaccess_32 macro whitespace fixes
arch/sparc: uaccess_64 macro whitespace fixes
blackfin: macro whitespace fixes
microblaze: whitespace fix
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
s390: macro whitespace fixes
sh: macro whitespace fixes
xtensa: macro whitespace fixes
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/microblaze/include/asm/uaccess.h | 6 +-
arch/openrisc/include/asm/uaccess.h | 4 +-
arch/parisc/include/asm/uaccess.h | 116 +++++------
arch/s390/include/asm/uaccess.h | 4 +-
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 | 364 +++++++++++++++++++++-------------
arch/sparc/include/asm/uaccess_64.h | 246 +++++++++++++----------
arch/tile/include/asm/uaccess.h | 6 +-
arch/x86/include/asm/uaccess.h | 2 +-
arch/xtensa/include/asm/uaccess.h | 90 ++++-----
24 files changed, 759 insertions(+), 620 deletions(-)
--
MST
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/