linux/arch
Nathan Chancellor f9cd5f91a8 powerpc: Avoid clang uninitialized warning in __get_user_size_allowed
Commit 9975f852ce ("powerpc/uaccess: Remove calls to __get_user_bad()
and __put_user_bad()") switch to BUILD_BUG() in the default case, which
leaves x uninitialized. This will not be an issue because the build will
be broken in that case but clang does static analysis before it realizes
the default case will be done so it warns about x being uninitialized
(trimmed for brevity):

 In file included from mm/mprotect.c:13:
 In file included from ./include/linux/hugetlb.h:28:
 In file included from ./include/linux/mempolicy.h:16:
 ./include/linux/pagemap.h:772:16: warning: variable '__gu_val' is used
 uninitialized whenever switch default is taken [-Wsometimes-uninitialized]
                 if (unlikely(__get_user(c, uaddr) != 0))
                              ^~~~~~~~~~~~~~~~~~~~
 ./arch/powerpc/include/asm/uaccess.h:266:2: note: expanded from macro '__get_user'
         __get_user_size_allowed(__gu_val, __gu_addr, __gu_size, __gu_err);      \
         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 ./arch/powerpc/include/asm/uaccess.h:235:2: note: expanded from macro
 '__get_user_size_allowed'
        default: BUILD_BUG();                                   \
        ^~~~~~~

Commit 5cd29b1fd3 ("powerpc/uaccess: Use asm goto for get_user when
compiler supports it") added an initialization for x because of the same
reason. Do the same thing here so there is no warning across all
versions of clang.

Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Acked-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://github.com/ClangBuiltLinux/linux/issues/1359
Link: https://lore.kernel.org/r/20210426203518.981550-1-nathan@kernel.org
2021-04-28 23:34:50 +10:00
..
alpha io_uring-worker.v3-2021-02-25 2021-02-27 08:29:02 -08:00
arc
arm A set of irqchip updates: 2021-03-14 13:33:33 -07:00
arm64 lib/vdso: Add vdso_data pointer as input to __arch_get_timens_vdso_data() 2021-04-14 23:04:44 +10:00
csky arch/csky patches for 5.12-rc1 2021-02-28 12:06:45 -08:00
h8300
hexagon io_uring-worker.v3-2021-02-25 2021-02-27 08:29:02 -08:00
ia64 ia64: fix ptrace(PTRACE_SYSCALL_INFO_EXIT) sign 2021-03-13 11:27:31 -08:00
m68k m68k: Fix virt_addr_valid() W=1 compiler warnings 2021-03-06 14:15:07 +01:00
microblaze io_uring-worker.v3-2021-02-25 2021-02-27 08:29:02 -08:00
mips MIPS: kernel: Reserve exception base early to prevent corruption 2021-03-09 11:22:59 +01:00
nds32 io_uring-worker.v3-2021-02-25 2021-02-27 08:29:02 -08:00
nios2 io_uring-worker.v3-2021-02-25 2021-02-27 08:29:02 -08:00
openrisc io_uring-worker.v3-2021-02-25 2021-02-27 08:29:02 -08:00
parisc arch/parisc/kernel: remove duplicate include in ptrace 2021-03-04 09:12:29 +01:00
powerpc powerpc: Avoid clang uninitialized warning in __get_user_size_allowed 2021-04-28 23:34:50 +10:00
riscv RISC-V Patches for the 5.12 Merge Window, Part 2 2021-02-28 12:01:23 -08:00
s390 lib/vdso: Add vdso_data pointer as input to __arch_get_timens_vdso_data() 2021-04-14 23:04:44 +10:00
sh io_uring-worker.v3-2021-02-25 2021-02-27 08:29:02 -08:00
sparc Merge git://git.kernel.org:/pub/scm/linux/kernel/git/davem/sparc 2021-03-09 17:08:41 -08:00
um io_uring-worker.v3-2021-02-25 2021-02-27 08:29:02 -08:00
x86 lib/vdso: Add vdso_data pointer as input to __arch_get_timens_vdso_data() 2021-04-14 23:04:44 +10:00
xtensa io_uring-worker.v3-2021-02-25 2021-02-27 08:29:02 -08:00
.gitignore
Kconfig kbuild: remove LLVM=1 test from HAS_LTO_CLANG 2021-03-11 14:52:55 +09:00