linux-kernel - [intel-tdx:kvm-upstream-workaround 434/442] arch/x86/kvm/mmu/mmu.c:981:21: warning: variable 'type' set but not used

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Message-ID: <202206280555.alASo2T9-lkp@intel.com>
Date:   Tue, 28 Jun 2022 05:29:12 +0800
From:   kernel test robot <lkp@...el.com>
To:     Isaku Yamahata <isaku.yamahata@...el.com>
Cc:     llvm@...ts.linux.dev, kbuild-all@...ts.01.org,
        linux-kernel@...r.kernel.org
Subject: [intel-tdx:kvm-upstream-workaround 434/442]
 arch/x86/kvm/mmu/mmu.c:981:21: warning: variable 'type' set but not used

tree:   https://github.com/intel/tdx.git kvm-upstream-workaround
head:   8af973ebaf30642129fc1ca63f155a469f9615ed
commit: 2cf2a8208ae24b96f074aac76f0feef63489137d [434/442] KVM: x86/mmu: update lpage_info on changing page_type
config: x86_64-randconfig-a004-20220627 (https://download.01.org/0day-ci/archive/20220628/202206280555.alASo2T9-lkp@intel.com/config)
compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project 016342e319fd31e41cf5ed16a6140a8ea2de74dd)
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
        # https://github.com/intel/tdx/commit/2cf2a8208ae24b96f074aac76f0feef63489137d
        git remote add intel-tdx https://github.com/intel/tdx.git
        git fetch --no-tags intel-tdx kvm-upstream-workaround
        git checkout 2cf2a8208ae24b96f074aac76f0feef63489137d
        # 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=x86_64 SHELL=/bin/bash arch/x86/kvm/

If you fix the issue, kindly add following tag where applicable
Reported-by: kernel test robot <lkp@...el.com>

All warnings (new ones prefixed by >>):

>> arch/x86/kvm/mmu/mmu.c:981:21: warning: variable 'type' set but not used [-Wunused-but-set-variable]
           enum kvm_page_type type;
                              ^
   1 warning generated.


vim +/type +981 arch/x86/kvm/mmu/mmu.c

aa7e272e931503 Xiaoyao Li     2021-08-31  976  
dbe93493d57473 Xiaoyao Li     2022-05-25  977  static void split_page_type(gfn_t gfn, struct kvm_memory_slot *slot,
dbe93493d57473 Xiaoyao Li     2022-05-25  978  			    enum pg_level level)
aa7e272e931503 Xiaoyao Li     2021-08-31  979  {
aa7e272e931503 Xiaoyao Li     2021-08-31  980  	struct kvm_page_attr *page_attr = page_attr_slot(gfn, slot, level);
aa7e272e931503 Xiaoyao Li     2021-08-31 @981  	enum kvm_page_type type;
aa7e272e931503 Xiaoyao Li     2021-08-31  982  	gfn_t base_gfn;
aa7e272e931503 Xiaoyao Li     2021-08-31  983  
aa7e272e931503 Xiaoyao Li     2021-08-31  984  	if (WARN_ON_ONCE(!kvm_page_type_valid(page_attr) || level <= PG_LEVEL_4K))
aa7e272e931503 Xiaoyao Li     2021-08-31  985  		return;
aa7e272e931503 Xiaoyao Li     2021-08-31  986  
aa7e272e931503 Xiaoyao Li     2021-08-31  987  	base_gfn = gfn & ~(KVM_PAGES_PER_HPAGE(level) - 1);
aa7e272e931503 Xiaoyao Li     2021-08-31  988  	type = page_attr->type;
dbe93493d57473 Xiaoyao Li     2022-05-25  989  
aa7e272e931503 Xiaoyao Li     2021-08-31  990  	/*
aa7e272e931503 Xiaoyao Li     2021-08-31  991  	 * Set the type to KVM_PAGE_TYPE_MIXED in advance since when a large
aa7e272e931503 Xiaoyao Li     2021-08-31  992  	 * page needs to be split means one of the 4K page of it needs to be
aa7e272e931503 Xiaoyao Li     2021-08-31  993  	 * changed to oppsite type
aa7e272e931503 Xiaoyao Li     2021-08-31  994  	 */
2cf2a8208ae24b Isaku Yamahata 2022-06-02  995  	page_type_set(page_attr, KVM_PAGE_TYPE_MIXED, base_gfn, slot, level);
aa7e272e931503 Xiaoyao Li     2021-08-31  996  }
aa7e272e931503 Xiaoyao Li     2021-08-31  997  

:::::: The code at line 981 was first introduced by commit
:::::: aa7e272e931503dda524bd4f15d098a0d4ac28d7 KVM: MMU: Update page_attr->type when guest converts the page

:::::: TO: Xiaoyao Li <xiaoyao.li@...el.com>
:::::: CC: Isaku Yamahata <isaku.yamahata@...el.com>

-- 
0-DAY CI Kernel Test Service
https://01.org/lkp