Hi Johannes,

FYI, the error/warning still remains.

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head:   c3d0e3fd41b7f0f5d5d5b6022ab7e813f04ea727
commit: a30cc14fe49c2d5913caf6b987d7cbd86c5e370b um: Don't use generic barrier.h
date:   1 year, 8 months ago
config: um-randconfig-r011-20210520 (attached as .config)
compiler: gcc-9 (Debian 9.3.0-22) 9.3.0
reproduce (this is a W=1 build):
        # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=a30cc14fe49c2d5913caf6b987d7cbd86c5e370b
        git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
        git fetch --no-tags linus master
        git checkout a30cc14fe49c2d5913caf6b987d7cbd86c5e370b
        # save the attached .config to linux build tree
        make W=1 ARCH=um 

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 >>):

>> /usr/bin/ld: kernel/irq/generic-chip.o:(.altinstructions+0x8): undefined reference to `X86_FEATURE_XMM2'
>> /usr/bin/ld: kernel/irq/generic-chip.o:(.altinstructions+0x15): undefined reference to `X86_FEATURE_XMM'
   /usr/bin/ld: drivers/misc/altera-stapl/altera-lpt.o:(.altinstructions+0x8): undefined reference to `X86_FEATURE_XMM2'
   /usr/bin/ld: drivers/misc/altera-stapl/altera-lpt.o:(.altinstructions+0x15): undefined reference to `X86_FEATURE_XMM'
   /usr/bin/ld: drivers/fpga/altera-pr-ip-core.o:(.altinstructions+0x8): undefined reference to `X86_FEATURE_XMM2'
   /usr/bin/ld: drivers/fpga/altera-pr-ip-core.o:(.altinstructions+0x15): undefined reference to `X86_FEATURE_XMM'
   collect2: error: ld returned 1 exit status

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0-DAY CI Kernel Test Service, Intel Corporation
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