Re: [PATCH v5 5/5] powerpc/inst: Optimise copy_inst_from_kernel_nofault()

kernel test robot
2021-12-01T06:46:11Z

Hi Christophe,

I love your patch! Perhaps something to improve:

[auto build test WARNING on powerpc/next]
[also build test WARNING on v5.16-rc3 next-20211201]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url: https://github.com/0day-ci/linux/commits/Christophe-Leroy/powerpc-inst-Refactor-___get_user_instr/20211130-015346
base: https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git next
config: powerpc64-randconfig-r021-20211201 (https://download.01.org/0day-ci/archive/20211201/202112011435.ttoYYtbC-lkp@intel.com/config)
compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project 25eb7fa01d7ebbe67648ea03841cda55b4239ab2)
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# install powerpc64 cross compiling tool for clang build
# apt-get install binutils-powerpc64-linux-gnu
# https://github.com/0day-ci/linux/commit/fb7bff30cc0efc7e4df1b48bb69de1f325eee826
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review Christophe-Leroy/powerpc-inst-Refactor-___get_user_instr/20211130-015346
git checkout fb7bff30cc0efc7e4df1b48bb69de1f325eee826
# save the config file to linux build tree
mkdir build_dir
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=powerpc prepare

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

In file included from include/linux/kernel_stat.h:9:
In file included from include/linux/interrupt.h:11:
In file included from include/linux/hardirq.h:11:
In file included from arch/powerpc/include/asm/hardirq.h:6:
In file included from include/linux/irq.h:20:
In file included from include/linux/io.h:13:
In file included from arch/powerpc/include/asm/io.h:619:
arch/powerpc/include/asm/io-defs.h:47:1: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
DEF_PCI_AC_NORET(insl, (unsigned long p, void *b, unsigned long c),
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
arch/powerpc/include/asm/io.h:616:3: note: expanded from macro 'DEF_PCI_AC_NORET'
__do_##name al; \
^~~~~~~~~~~~~~
<scratch space>:143:1: note: expanded from here
__do_insl
^
arch/powerpc/include/asm/io.h:558:56: note: expanded from macro '__do_insl'
#define __do_insl(p, b, n) readsl((PCI_IO_ADDR)_IO_BASE+(p), (b), (n))
~~~~~~~~~~~~~~~~~~~~~^
In file included from arch/powerpc/kernel/asm-offsets.c:21:
In file included from include/linux/suspend.h:5:
In file included from include/linux/swap.h:9:
In file included from include/linux/memcontrol.h:13:
In file included from include/linux/cgroup.h:26:
In file included from include/linux/kernel_stat.h:9:
In file included from include/linux/interrupt.h:11:
In file included from include/linux/hardirq.h:11:
In file included from arch/powerpc/include/asm/hardirq.h:6:
In file included from include/linux/irq.h:20:
In file included from include/linux/io.h:13:
In file included from arch/powerpc/include/asm/io.h:619:
arch/powerpc/include/asm/io-defs.h:49:1: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
DEF_PCI_AC_NORET(outsb, (unsigned long p, const void *b, unsigned long c),
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
arch/powerpc/include/asm/io.h:616:3: note: expanded from macro 'DEF_PCI_AC_NORET'
__do_##name al; \
^~~~~~~~~~~~~~
<scratch space>:145:1: note: expanded from here
__do_outsb
^
arch/powerpc/include/asm/io.h:559:58: note: expanded from macro '__do_outsb'
#define __do_outsb(p, b, n) writesb((PCI_IO_ADDR)_IO_BASE+(p),(b),(n))
~~~~~~~~~~~~~~~~~~~~~^
In file included from arch/powerpc/kernel/asm-offsets.c:21:
In file included from include/linux/suspend.h:5:
In file included from include/linux/swap.h:9:
In file included from include/linux/memcontrol.h:13:
In file included from include/linux/cgroup.h:26:
In file included from include/linux/kernel_stat.h:9:
In file included from include/linux/interrupt.h:11:
In file included from include/linux/hardirq.h:11:
In file included from arch/powerpc/include/asm/hardirq.h:6:
In file included from include/linux/irq.h:20:
In file included from include/linux/io.h:13:
In file included from arch/powerpc/include/asm/io.h:619:
arch/powerpc/include/asm/io-defs.h:51:1: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
DEF_PCI_AC_NORET(outsw, (unsigned long p, const void *b, unsigned long c),
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
arch/powerpc/include/asm/io.h:616:3: note: expanded from macro 'DEF_PCI_AC_NORET'
__do_##name al; \
^~~~~~~~~~~~~~
<scratch space>:147:1: note: expanded from here
__do_outsw
^
arch/powerpc/include/asm/io.h:560:58: note: expanded from macro '__do_outsw'
#define __do_outsw(p, b, n) writesw((PCI_IO_ADDR)_IO_BASE+(p),(b),(n))
~~~~~~~~~~~~~~~~~~~~~^
In file included from arch/powerpc/kernel/asm-offsets.c:21:
In file included from include/linux/suspend.h:5:
In file included from include/linux/swap.h:9:
In file included from include/linux/memcontrol.h:13:
In file included from include/linux/cgroup.h:26:
In file included from include/linux/kernel_stat.h:9:
In file included from include/linux/interrupt.h:11:
In file included from include/linux/hardirq.h:11:
In file included from arch/powerpc/include/asm/hardirq.h:6:
In file included from include/linux/irq.h:20:
In file included from include/linux/io.h:13:
In file included from arch/powerpc/include/asm/io.h:619:
arch/powerpc/include/asm/io-defs.h:53:1: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
DEF_PCI_AC_NORET(outsl, (unsigned long p, const void *b, unsigned long c),
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
arch/powerpc/include/asm/io.h:616:3: note: expanded from macro 'DEF_PCI_AC_NORET'
__do_##name al; \
^~~~~~~~~~~~~~
<scratch space>:149:1: note: expanded from here
__do_outsl
^
arch/powerpc/include/asm/io.h:561:58: note: expanded from macro '__do_outsl'
#define __do_outsl(p, b, n) writesl((PCI_IO_ADDR)_IO_BASE+(p),(b),(n))
~~~~~~~~~~~~~~~~~~~~~^
In file included from arch/powerpc/kernel/asm-offsets.c:71:
In file included from arch/powerpc/kernel/../xmon/xmon_bpts.h:7:
arch/powerpc/include/asm/inst.h:161:41: warning: variable 'val' is uninitialized when used here [-Wuninitialized]
if (IS_ENABLED(CONFIG_PPC64) && get_op(val) == OP_PREFIX) {
^~~
arch/powerpc/include/asm/inst.h:155:18: note: initialize the variable 'val' to silence this warning
unsigned int val, suffix;
^
= 0
>> arch/powerpc/include/asm/inst.h:163:32: warning: variable 'suffix' is uninitialized when used here [-Wuninitialized]
*inst = ppc_inst_prefix(val, suffix);
^~~~~~
arch/powerpc/include/asm/inst.h:62:69: note: expanded from macro 'ppc_inst_prefix'
#define ppc_inst_prefix(x, y) ((ppc_inst_t){ .val = (x), .suffix = (y) })
^
arch/powerpc/include/asm/inst.h:155:26: note: initialize the variable 'suffix' to silence this warning
unsigned int val, suffix;
^
= 0
14 warnings generated.
<stdin>:1559:2: warning: syscall futex_waitv not implemented [-W#warnings]
#warning syscall futex_waitv not implemented
^
1 warning generated.
/usr/bin/ld: unrecognised emulation mode: elf64ppc
Supported emulations: elf_x86_64 elf32_x86_64 elf_i386 elf_iamcu elf_l1om elf_k1om i386pep i386pe
clang-14: error: linker command failed with exit code 1 (use -v to see invocation)
make[2]: *** [arch/powerpc/kernel/vdso64/Makefile:44: arch/powerpc/kernel/vdso64/vdso64.so.dbg] Error 1
make[2]: Target 'include/generated/vdso64-offsets.h' not remade because of errors.
make[1]: *** [arch/powerpc/Makefile:422: vdso_prepare] Error 2
make[1]: Target 'prepare' not remade because of errors.
make: *** [Makefile:219: __sub-make] Error 2
make: Target 'prepare' not remade because of errors.

vim +/suffix +163 arch/powerpc/include/asm/inst.h

152
153 static inline int copy_inst_from_kernel_nofault(ppc_inst_t *inst, u32 *src)
154 {
155 unsigned int val, suffix;
156
157 if (unlikely(!is_kernel_addr((unsigned long)src)))
158 return -ERANGE;
159
160 __get_kernel_nofault(&val, src, u32, Efault);
161 if (IS_ENABLED(CONFIG_PPC64) && get_op(val) == OP_PREFIX) {
162 __get_kernel_nofault(&suffix, src + 1, u32, Efault);
> 163 *inst = ppc_inst_prefix(val, suffix);
164 } else {
165 *inst = ppc_inst(val);
166 }
167 return 0;
168 Efault:
169 return -EFAULT;
170 }
171

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0-DAY CI Kernel Test Service, Intel Corporation