Re: [PATCH 3/3] KVM: x86/mmu: always take tdp_mmu_pages_lock

[kernel test robot <lkp@intel.com>]

Hi Paolo,

kernel test robot noticed the following build warnings:

[auto build test WARNING on kvm/queue]
[also build test WARNING on linus/master v6.6-rc3 next-20230929]
[cannot apply to mst-vhost/linux-next kvm/linux-next]
[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#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Paolo-Bonzini/KVM-x86-mmu-remove-unnecessary-bool-shared-argument-from-functions/20230929-003259
base:   https://git.kernel.org/pub/scm/virt/kvm/kvm.git queue
patch link:    https://lore.kernel.org/r/20230928162959.1514661-4-pbonzini%40redhat.com
patch subject: [PATCH 3/3] KVM: x86/mmu: always take tdp_mmu_pages_lock
config: x86_64-buildonly-randconfig-004-20230929 (https://download.01.org/0day-ci/archive/20230929/202309291557.Eq3JDvT6-lkp@intel.com/config)
compiler: gcc-9 (Debian 9.3.0-22) 9.3.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20230929/202309291557.Eq3JDvT6-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202309291557.Eq3JDvT6-lkp@intel.com/

All warnings (new ones prefixed by >>):

>> arch/x86/kvm/mmu/tdp_mmu.c:289: warning: Excess function parameter 'shared' description in 'tdp_mmu_unlink_sp'


vim +289 arch/x86/kvm/mmu/tdp_mmu.c

43a063cab325ee7 Yosry Ahmed         2022-08-23  278  
a9442f594147f95 Ben Gardon          2021-02-02  279  /**
c298a30c2821cb0 David Matlack       2022-01-19  280   * tdp_mmu_unlink_sp() - Remove a shadow page from the list of used pages
a9442f594147f95 Ben Gardon          2021-02-02  281   *
a9442f594147f95 Ben Gardon          2021-02-02  282   * @kvm: kvm instance
a9442f594147f95 Ben Gardon          2021-02-02  283   * @sp: the page to be removed
9a77daacc87dee9 Ben Gardon          2021-02-02  284   * @shared: This operation may not be running under the exclusive use of
9a77daacc87dee9 Ben Gardon          2021-02-02  285   *	    the MMU lock and the operation must synchronize with other
9a77daacc87dee9 Ben Gardon          2021-02-02  286   *	    threads that might be adding or removing pages.
a9442f594147f95 Ben Gardon          2021-02-02  287   */
44f1ce87ebc1ca1 Paolo Bonzini       2023-09-28  288  static void tdp_mmu_unlink_sp(struct kvm *kvm, struct kvm_mmu_page *sp)
a9442f594147f95 Ben Gardon          2021-02-02 @289  {
44f1ce87ebc1ca1 Paolo Bonzini       2023-09-28  290  	lockdep_assert_held(&kvm->mmu_lock);
44f1ce87ebc1ca1 Paolo Bonzini       2023-09-28  291  
43a063cab325ee7 Yosry Ahmed         2022-08-23  292  	tdp_unaccount_mmu_page(kvm, sp);
d25ceb9264364dc Sean Christopherson 2022-10-19  293  
d25ceb9264364dc Sean Christopherson 2022-10-19  294  	if (!sp->nx_huge_page_disallowed)
d25ceb9264364dc Sean Christopherson 2022-10-19  295  		return;
d25ceb9264364dc Sean Christopherson 2022-10-19  296  
9a77daacc87dee9 Ben Gardon          2021-02-02  297  	spin_lock(&kvm->arch.tdp_mmu_pages_lock);
61f94478547bb4f Sean Christopherson 2022-10-19  298  	sp->nx_huge_page_disallowed = false;
61f94478547bb4f Sean Christopherson 2022-10-19  299  	untrack_possible_nx_huge_page(kvm, sp);
9a77daacc87dee9 Ben Gardon          2021-02-02  300  	spin_unlock(&kvm->arch.tdp_mmu_pages_lock);
a9442f594147f95 Ben Gardon          2021-02-02  301  }
a9442f594147f95 Ben Gardon          2021-02-02  302  

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