[kbuild-all] [linux-stable-rc:linux-4.4.y 8875/9999] arch/x86/kvm/pmu_intel.c:93:10: warning: comparison of integers of different signs: 'int' and 'size_t' (aka 'unsigned long')

Thursday, 10 December 2020

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git
linux-4.4.y
head:   95a3867e897abd7811196123f81a119a75aba863
commit: c3ccf2fdfc89871042659ae1463fd1d9665fdfef [8875/9999] KVM: x86: Protect pmu_intel.c
from Spectre-v1/L1TF attacks
config: x86_64-randconfig-a016-20201208 (attached as .config)
compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project
a2f922140f5380571fb74179f2bf622b3b925697)
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 x86_64 cross compiling tool for clang build
        # apt-get install binutils-x86-64-linux-gnu
        #
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.gi...
        git remote add linux-stable-rc
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git
        git fetch --no-tags linux-stable-rc linux-4.4.y
        git checkout c3ccf2fdfc89871042659ae1463fd1d9665fdfef
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp(a)intel.com&gt;

All warnings (new ones prefixed by >>):

   arch/x86/include/asm/uaccess.h:772:26: warning: comparison of integers of different
signs: 'int' and 'unsigned long' [-Wsign-compare]
           if (likely(sz < 0 || sz >= n))
                                ~~ ^  ~
   include/linux/compiler.h:150:73: note: expanded from macro 'likely'
   #  define likely(x)     (__builtin_constant_p(x) ? !!(x) : __branch_check__(x, 1))
                                                                               ^
   include/linux/compiler.h:139:29: note: expanded from macro '__branch_check__'
                           ______r = likely_notrace(x);                    \
                                                    ^
   include/linux/compiler.h:126:47: note: expanded from macro 'likely_notrace'
   #define likely_notrace(x)       __builtin_expect(!!(x), 1)
                                                       ^
   In file included from arch/x86/kvm/pmu_intel.c:15:
   In file included from include/linux/kvm_host.h:10:
   In file included from include/linux/hardirq.h:8:
   In file included from arch/x86/include/asm/hardirq.h:5:
   In file included from include/linux/irq.h:418:
   In file included from arch/x86/include/asm/hw_irq.h:26:
   In file included from arch/x86/include/asm/sections.h:5:
   arch/x86/include/asm/uaccess.h:772:26: warning: comparison of integers of different
signs: 'int' and 'unsigned long' [-Wsign-compare]
           if (likely(sz < 0 || sz >= n))
                                ~~ ^  ~
   include/linux/compiler.h:150:43: note: expanded from macro 'likely'
   #  define likely(x)     (__builtin_constant_p(x) ? !!(x) : __branch_check__(x, 1))
                                                 ^
   In file included from arch/x86/kvm/pmu_intel.c:15:
   In file included from include/linux/kvm_host.h:10:
   In file included from include/linux/hardirq.h:8:
   In file included from arch/x86/include/asm/hardirq.h:5:
   In file included from include/linux/irq.h:418:
   In file included from arch/x86/include/asm/hw_irq.h:26:
   In file included from arch/x86/include/asm/sections.h:5:
   arch/x86/include/asm/uaccess.h:772:26: warning: comparison of integers of different
signs: 'int' and 'unsigned long' [-Wsign-compare]
           if (likely(sz < 0 || sz >= n))
                                ~~ ^  ~
   include/linux/compiler.h:150:51: note: expanded from macro 'likely'
   #  define likely(x)     (__builtin_constant_p(x) ? !!(x) : __branch_check__(x, 1))
                                                         ^
   In file included from arch/x86/kvm/pmu_intel.c:15:
   In file included from include/linux/kvm_host.h:15:
   In file included from include/linux/sched.h:61:
   In file included from include/linux/cgroup-defs.h:16:
   include/linux/percpu-refcount.h:177:3: warning: comparison of integers of different
signs: 'unsigned long' and 'int' [-Wsign-compare]
                   this_cpu_add(*percpu_count, nr);
                   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   include/linux/percpu-defs.h:526:33: note: expanded from macro 'this_cpu_add'
   #define this_cpu_add(pcp, val)          __pcpu_size_call(this_cpu_add_, pcp, val)
                                           ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   include/linux/percpu-defs.h:397:11: note: expanded from macro
'__pcpu_size_call'
                   case 8: stem##8(variable, __VA_ARGS__);break;           \
                           ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   <scratch space>:261:1: note: expanded from here
   this_cpu_add_8
   ^
   arch/x86/include/asm/percpu.h:478:35: note: expanded from macro
'this_cpu_add_8'
   #define this_cpu_add_8(pcp, val)                percpu_add_op((pcp), val)
                                                   ^~~~~~~~~~~~~~~~~~~~~~~~~
   arch/x86/include/asm/percpu.h:130:31: note: expanded from macro
'percpu_add_op'
                                 ((val) == 1 || (val) == -1)) ?            \
                                                 ~~~  ^  ~~
   In file included from arch/x86/kvm/pmu_intel.c:15:
   In file included from include/linux/kvm_host.h:15:
   In file included from include/linux/sched.h:61:
   In file included from include/linux/cgroup-defs.h:16:
   include/linux/percpu-refcount.h:276:3: warning: comparison of integers of different
signs: 'unsigned long' and 'int' [-Wsign-compare]
                   this_cpu_sub(*percpu_count, nr);
                   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   include/linux/percpu-defs.h:536:33: note: expanded from macro 'this_cpu_sub'
   #define this_cpu_sub(pcp, val)          this_cpu_add(pcp, -(typeof(pcp))(val))
                                           ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   include/linux/percpu-defs.h:526:33: note: expanded from macro 'this_cpu_add'
   #define this_cpu_add(pcp, val)          __pcpu_size_call(this_cpu_add_, pcp, val)
                                           ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   include/linux/percpu-defs.h:397:11: note: expanded from macro
'__pcpu_size_call'
                   case 8: stem##8(variable, __VA_ARGS__);break;           \
                           ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   <scratch space>:97:1: note: expanded from here
   this_cpu_add_8
   ^
   arch/x86/include/asm/percpu.h:478:35: note: expanded from macro
'this_cpu_add_8'
   #define this_cpu_add_8(pcp, val)                percpu_add_op((pcp), val)
                                                   ^~~~~~~~~~~~~~~~~~~~~~~~~
   arch/x86/include/asm/percpu.h:130:31: note: expanded from macro
'percpu_add_op'
                                 ((val) == 1 || (val) == -1)) ?            \
                                                 ~~~  ^  ~~
   In file included from arch/x86/kvm/pmu_intel.c:18:
   In file included from arch/x86/kvm/x86.h:5:
   arch/x86/kvm/kvm_cache_regs.h:43:32: warning: implicit conversion from enumeration type
'enum kvm_reg_ex' to different enumeration type 'enum kvm_reg'
[-Wenum-conversion]
                   kvm_x86_ops->cache_reg(vcpu, VCPU_EXREG_PDPTR);
                   ~~~~~~~~~~~                  ^~~~~~~~~~~~~~~~
   In file included from arch/x86/kvm/pmu_intel.c:21:
   arch/x86/kvm/pmu.h:100:10: warning: comparison of integers of different signs:
'u32' (aka 'unsigned int') and 'int' [-Wsign-compare]
           if (msr >= base && msr < base + pmu->nr_arch_fixed_counters)
{
               ~~~ ^  ~~~~
   arch/x86/kvm/pmu_intel.c:42:16: warning: comparison of integers of different signs:
'int' and 'unsigned int' [-Wsign-compare]
           for (i = 0; i < pmu->nr_arch_fixed_counters; i++) {
                       ~ ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~
   arch/x86/kvm/pmu_intel.c:76:16: warning: comparison of integers of different signs:
'int' and 'unsigned long' [-Wsign-compare]
           for (i = 0; i < ARRAY_SIZE(intel_arch_events); i++)
                       ~ ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
...
> arch/x86/kvm/pmu_intel.c:93:10: warning: comparison of integers
of different signs: 'int' and 'size_t' (aka 'unsigned long')
[-Wsign-compare]            if (idx >= size)
               ~~~ ^  ~~~~
   13 warnings generated.

vim +93 arch/x86/kvm/pmu_intel.c

    87	
    88	static unsigned intel_find_fixed_event(int idx)
    89	{
    90		u32 event;
    91		size_t size = ARRAY_SIZE(fixed_pmc_events);
    92	
...
 93		if (idx >= size)     94			return PERF_COUNT_HW_MAX;
    95	
    96		event = fixed_pmc_events[array_index_nospec(idx, size)];
    97		return intel_arch_events[event].event_type;
    98	}
    99	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org

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[kbuild-all] [linux-stable-rc:linux-4.4.y 8875/9999] arch/x86/kvm/pmu_intel.c:93:10: warning: comparison of integers of different signs: 'int' and 'size_t' (aka 'unsigned long')