diff options
author | Arnd Bergmann <arnd@arndb.de> | 2015-01-14 23:17:49 +0100 |
---|---|---|
committer | Arnd Bergmann <arnd@arndb.de> | 2015-01-14 23:17:49 +0100 |
commit | 643165c8bbc8617d8222cb50c89e34fe64d226cf (patch) | |
tree | e2a88de9b8efb0c9fa2436f53b0a3ab4948c4a55 /arch/m68k | |
parent | eaa27f34e91a14cdceed26ed6c6793ec1d186115 (diff) | |
parent | 0795cb1b46e7938ed679ccd48f933e75272b30e3 (diff) |
Merge tag 'uaccess_for_upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost into asm-generic
Merge "uaccess: fix sparse warning on get/put_user for bitwise types" from Michael S. Tsirkin:
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>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
* tag 'uaccess_for_upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (37 commits)
sparc32: nocheck uaccess coding style tweaks
sparc64: nocheck uaccess coding style tweaks
xtensa: macro whitespace fixes
sh: macro whitespace fixes
parisc: macro whitespace fixes
m68k: macro whitespace fixes
m32r: macro whitespace fixes
frv: macro whitespace fixes
cris: macro whitespace fixes
avr32: macro whitespace fixes
arm64: macro whitespace fixes
arm: macro whitespace fixes
alpha: macro whitespace fixes
blackfin: macro whitespace fixes
sparc64: uaccess_64 macro whitespace fixes
sparc32: uaccess_32 macro whitespace fixes
avr32: whitespace fix
sh: fix put_user sparse errors
metag: fix put_user sparse errors
ia64: fix put_user sparse errors
...
Diffstat (limited to 'arch/m68k')
-rw-r--r-- | arch/m68k/include/asm/segment.h | 2 | ||||
-rw-r--r-- | arch/m68k/include/asm/uaccess_mm.h | 40 |
2 files changed, 21 insertions, 21 deletions
diff --git a/arch/m68k/include/asm/segment.h b/arch/m68k/include/asm/segment.h index 0fa80e97ed2d..98216b8111f0 100644 --- a/arch/m68k/include/asm/segment.h +++ b/arch/m68k/include/asm/segment.h @@ -58,7 +58,7 @@ static inline mm_segment_t get_ds(void) #define set_fs(x) (current_thread_info()->addr_limit = (x)) #endif -#define segment_eq(a,b) ((a).seg == (b).seg) +#define segment_eq(a, b) ((a).seg == (b).seg) #endif /* __ASSEMBLY__ */ diff --git a/arch/m68k/include/asm/uaccess_mm.h b/arch/m68k/include/asm/uaccess_mm.h index 15901db435b9..d228601b3afc 100644 --- a/arch/m68k/include/asm/uaccess_mm.h +++ b/arch/m68k/include/asm/uaccess_mm.h @@ -128,25 +128,25 @@ asm volatile ("\n" \ #define put_user(x, ptr) __put_user(x, ptr) -#define __get_user_asm(res, x, ptr, type, bwl, reg, err) ({ \ - type __gu_val; \ - asm volatile ("\n" \ - "1: "MOVES"."#bwl" %2,%1\n" \ - "2:\n" \ - " .section .fixup,\"ax\"\n" \ - " .even\n" \ - "10: move.l %3,%0\n" \ - " sub.l %1,%1\n" \ - " jra 2b\n" \ - " .previous\n" \ - "\n" \ - " .section __ex_table,\"a\"\n" \ - " .align 4\n" \ - " .long 1b,10b\n" \ - " .previous" \ - : "+d" (res), "=&" #reg (__gu_val) \ - : "m" (*(ptr)), "i" (err)); \ - (x) = (typeof(*(ptr)))(unsigned long)__gu_val; \ +#define __get_user_asm(res, x, ptr, type, bwl, reg, err) ({ \ + type __gu_val; \ + asm volatile ("\n" \ + "1: "MOVES"."#bwl" %2,%1\n" \ + "2:\n" \ + " .section .fixup,\"ax\"\n" \ + " .even\n" \ + "10: move.l %3,%0\n" \ + " sub.l %1,%1\n" \ + " jra 2b\n" \ + " .previous\n" \ + "\n" \ + " .section __ex_table,\"a\"\n" \ + " .align 4\n" \ + " .long 1b,10b\n" \ + " .previous" \ + : "+d" (res), "=&" #reg (__gu_val) \ + : "m" (*(ptr)), "i" (err)); \ + (x) = (__force typeof(*(ptr)))(__force unsigned long)__gu_val; \ }) #define __get_user(x, ptr) \ @@ -188,7 +188,7 @@ asm volatile ("\n" \ "+a" (__gu_ptr) \ : "i" (-EFAULT) \ : "memory"); \ - (x) = (typeof(*(ptr)))__gu_val; \ + (x) = (__force typeof(*(ptr)))__gu_val; \ break; \ } */ \ default: \ |