Re: arch/mips/include/asm/timex.h:75:10: error: instruction requires a CPU feature not currently enabled

From: Borislav Petkov
Date: Wed Apr 19 2023 - 18:39:02 EST

+ Thomas.

On Mon, Apr 17, 2023 at 07:57:04AM +0800, kernel test robot wrote:
> tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
> head: 6a8f57ae2eb07ab39a6f0ccad60c760743051026
> commit: aba5b397cad7d398b385aaf5029f99f41b690466 hamradio: baycom_epp: Do not use x86-specific rdtsc()
> date: 4 months ago
> config: mips-buildonly-randconfig-r001-20230417 (https://download.01.org/0day-ci/archive/20230417/202304170748.Fg9VIgGd-lkp@xxxxxxxxx/config)
> compiler: clang version 17.0.0 (https://github.com/llvm/llvm-project 9638da200e00bd069e6dd63604e14cbafede9324)

Where do I get clang 17?

In any case, this

"error: instruction requires a CPU feature not currently enabled"

sounds like clang is trying to generate invalid code for the wrong
target. .config issue?

> 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 mips cross compiling tool for clang build
> # apt-get install binutils-mipsel-linux-gnu
> # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=aba5b397cad7d398b385aaf5029f99f41b690466
> git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
> git fetch --no-tags linus master
> git checkout aba5b397cad7d398b385aaf5029f99f41b690466
> # save the config file
> mkdir build_dir && cp config build_dir/.config
> COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=mips olddefconfig
> COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=mips SHELL=/bin/bash drivers/net/hamradio/
>
> If you fix the issue, kindly add following tag where applicable
> | Reported-by: kernel test robot <lkp@xxxxxxxxx>
> | Link: https://lore.kernel.org/oe-kbuild-all/202304170748.Fg9VIgGd-lkp@xxxxxxxxx/
>
> All errors (new ones prefixed by >>):
>
> In file included from drivers/net/hamradio/baycom_epp.c:29:
> In file included from include/linux/module.h:13:
> In file included from include/linux/stat.h:19:
> In file included from include/linux/time.h:60:
> In file included from include/linux/time32.h:13:
> In file included from include/linux/timex.h:67:
> >> arch/mips/include/asm/timex.h:75:10: error: instruction requires a CPU feature not currently enabled
> return read_c0_count();
> ^
> arch/mips/include/asm/mipsregs.h:1712:26: note: expanded from macro 'read_c0_count'
> #define read_c0_count() __read_32bit_c0_register($9, 0)
> ^
> arch/mips/include/asm/mipsregs.h:1453:2: note: expanded from macro '__read_32bit_c0_register'
> ___read_32bit_c0_register(source, sel, __volatile__)
> ^
> arch/mips/include/asm/mipsregs.h:1419:4: note: expanded from macro '___read_32bit_c0_register'
> "mfc0\t%0, " #source "\n\t" \
> ^
> <inline asm>:1:2: note: instantiated into assembly here
> mfc0 $4, $9
> ^
> In file included from drivers/net/hamradio/baycom_epp.c:29:
> In file included from include/linux/module.h:13:
> In file included from include/linux/stat.h:19:
> In file included from include/linux/time.h:60:
> In file included from include/linux/time32.h:13:
> In file included from include/linux/timex.h:67:
> >> arch/mips/include/asm/timex.h:75:10: error: instruction requires a CPU feature not currently enabled
> return read_c0_count();
> ^
> arch/mips/include/asm/mipsregs.h:1712:26: note: expanded from macro 'read_c0_count'
> #define read_c0_count() __read_32bit_c0_register($9, 0)
> ^
> arch/mips/include/asm/mipsregs.h:1453:2: note: expanded from macro '__read_32bit_c0_register'
> ___read_32bit_c0_register(source, sel, __volatile__)
> ^
> arch/mips/include/asm/mipsregs.h:1419:4: note: expanded from macro '___read_32bit_c0_register'
> "mfc0\t%0, " #source "\n\t" \
> ^
> <inline asm>:1:2: note: instantiated into assembly here
> mfc0 $2, $9
> ^
> In file included from drivers/net/hamradio/baycom_epp.c:29:
> In file included from include/linux/module.h:13:
> In file included from include/linux/stat.h:19:
> In file included from include/linux/time.h:60:
> In file included from include/linux/time32.h:13:
> In file included from include/linux/timex.h:67:
> >> arch/mips/include/asm/timex.h:75:10: error: instruction requires a CPU feature not currently enabled
> return read_c0_count();
> ^
> arch/mips/include/asm/mipsregs.h:1712:26: note: expanded from macro 'read_c0_count'
> #define read_c0_count() __read_32bit_c0_register($9, 0)
> ^
> arch/mips/include/asm/mipsregs.h:1453:2: note: expanded from macro '__read_32bit_c0_register'
> ___read_32bit_c0_register(source, sel, __volatile__)
> ^
> arch/mips/include/asm/mipsregs.h:1419:4: note: expanded from macro '___read_32bit_c0_register'
> "mfc0\t%0, " #source "\n\t" \
> ^
> <inline asm>:1:2: note: instantiated into assembly here
> mfc0 $2, $9
> ^
> In file included from drivers/net/hamradio/baycom_epp.c:29:
> In file included from include/linux/module.h:13:
> In file included from include/linux/stat.h:19:
> In file included from include/linux/time.h:60:
> In file included from include/linux/time32.h:13:
> In file included from include/linux/timex.h:67:
> >> arch/mips/include/asm/timex.h:75:10: error: instruction requires a CPU feature not currently enabled
> return read_c0_count();
> ^
> arch/mips/include/asm/mipsregs.h:1712:26: note: expanded from macro 'read_c0_count'
> #define read_c0_count() __read_32bit_c0_register($9, 0)
> ^
> arch/mips/include/asm/mipsregs.h:1453:2: note: expanded from macro '__read_32bit_c0_register'
> ___read_32bit_c0_register(source, sel, __volatile__)
> ^
> arch/mips/include/asm/mipsregs.h:1419:4: note: expanded from macro '___read_32bit_c0_register'
> "mfc0\t%0, " #source "\n\t" \
> ^
> <inline asm>:1:2: note: instantiated into assembly here
> mfc0 $2, $9
> ^
> 4 errors generated.
>
>
> vim +75 arch/mips/include/asm/timex.h
>
> 9c9b415c50bc29 Ralf Baechle 2013-09-12 71
> 06947aaaf9bf7d Maciej W. Rozycki 2014-04-06 72 static inline cycles_t get_cycles(void)
> 06947aaaf9bf7d Maciej W. Rozycki 2014-04-06 73 {
> 06947aaaf9bf7d Maciej W. Rozycki 2014-04-06 74 if (can_use_mips_counter(read_c0_prid()))
> 9c9b415c50bc29 Ralf Baechle 2013-09-12 @75 return read_c0_count();
> 06947aaaf9bf7d Maciej W. Rozycki 2014-04-06 76 else
> 06947aaaf9bf7d Maciej W. Rozycki 2014-04-06 77 return 0; /* no usable counter */
> 9c9b415c50bc29 Ralf Baechle 2013-09-12 78 }
> 1c99c6a7c3c599 Jason A. Donenfeld 2022-04-08 79 #define get_cycles get_cycles
> 9c9b415c50bc29 Ralf Baechle 2013-09-12 80
>
> :::::: The code at line 75 was first introduced by commit
> :::::: 9c9b415c50bc298ac61412dff856eae2f54889ee MIPS: Reimplement get_cycles().
>
> :::::: TO: Ralf Baechle <ralf@xxxxxxxxxxxxxx>
> :::::: CC: Ralf Baechle <ralf@xxxxxxxxxxxxxx>
>
> --
> 0-DAY CI Kernel Test Service
> https://github.com/intel/lkp-tests

--
Regards/Gruss,
Boris.

https://people.kernel.org/tglx/notes-about-netiquette