Hi Christophe,

I love your patch! Yet something to improve:

[auto build test ERROR on powerpc/next]
[also build test ERROR on kbuild/for-next v5.12-rc7 next-20210412]
[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-bug-Remove-specific-powerpc-BUG_ON-and-WARN_ON-on-PPC32/20210413-002741
base:   https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git next
config: powerpc-randconfig-r035-20210412 (attached as .config)
compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project 9829f5e6b1bca9b61efc629770d28bb9014dec45)
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 powerpc cross compiling tool for clang build
        # apt-get install binutils-powerpc-linux-gnu
        # https://github.com/0day-ci/linux/commit/398ea05a716b58d231d62d20083a101488d155b4
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Christophe-Leroy/powerpc-bug-Remove-specific-powerpc-BUG_ON-and-WARN_ON-on-PPC32/20210413-002741
        git checkout 398ea05a716b58d231d62d20083a101488d155b4
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=powerpc 

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

All errors (new ones prefixed by >>):

   arch/powerpc/kernel/misc_32.S: Assembler messages:
>> arch/powerpc/kernel/misc_32.S:240: Error: unrecognized opcode: `emit_warn_entry'
   clang-13: error: assembler command failed with exit code 1 (use -v to see invocation)


vim +240 arch/powerpc/kernel/misc_32.S

   218	
   219	/*
   220	 * Copy a whole page.  We use the dcbz instruction on the destination
   221	 * to reduce memory traffic (it eliminates the unnecessary reads of
   222	 * the destination into cache).  This requires that the destination
   223	 * is cacheable.
   224	 */
   225	#define COPY_16_BYTES		\
   226		lwz	r6,4(r4);	\
   227		lwz	r7,8(r4);	\
   228		lwz	r8,12(r4);	\
   229		lwzu	r9,16(r4);	\
   230		stw	r6,4(r3);	\
   231		stw	r7,8(r3);	\
   232		stw	r8,12(r3);	\
   233		stwu	r9,16(r3)
   234	
   235	_GLOBAL(copy_page)
   236		rlwinm	r5, r3, 0, L1_CACHE_BYTES - 1
   237		addi	r3,r3,-4
   238	
   239	0:	twnei	r5, 0	/* WARN if r3 is not cache aligned */
 > 240		EMIT_WARN_ENTRY 0b,__FILE__,__LINE__, BUGFLAG_WARNING
   241	
   242		addi	r4,r4,-4
   243	
   244		li	r5,4
   245	

---
0-DAY CI Kernel Test Service, Intel Corporation
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