linux-kernel - arch/x86/kernel/cpu/mtrr/generic.c:259: warning: Function parameter or member 'var' not described in 'mtrr_overwrite

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [day] [month] [year] [list]

Message-ID: <202308310450.02aHerFe-lkp@intel.com>
Date:   Thu, 31 Aug 2023 04:32:00 +0800
From:   kernel test robot <lkp@...el.com>
To:     Juergen Gross <jgross@...e.com>
Cc:     llvm@...ts.linux.dev, oe-kbuild-all@...ts.linux.dev,
        linux-kernel@...r.kernel.org,
        "Borislav Petkov (AMD)" <bp@...en8.de>
Subject: arch/x86/kernel/cpu/mtrr/generic.c:259: warning: Function parameter
 or member 'var' not described in 'mtrr_overwrite_state'

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head:   1687d8aca5488674686eb46bf49d1d908b2672a1
commit: 29055dc74287467bd7a053d60b4afe753832960d x86/mtrr: Support setting MTRR state for software defined MTRRs
date:   3 months ago
config: i386-allnoconfig (https://download.01.org/0day-ci/archive/20230831/202308310450.02aHerFe-lkp@intel.com/config)
compiler: clang version 16.0.4 (https://github.com/llvm/llvm-project.git ae42196bc493ffe877a7e3dff8be32035dea4d07)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20230831/202308310450.02aHerFe-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@...el.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202308310450.02aHerFe-lkp@intel.com/

All warnings (new ones prefixed by >>):

   arch/x86/kernel/cpu/mtrr/generic.c:125: warning: Function parameter or member 'start' not described in 'mtrr_type_lookup_fixed'
   arch/x86/kernel/cpu/mtrr/generic.c:125: warning: Function parameter or member 'end' not described in 'mtrr_type_lookup_fixed'
   arch/x86/kernel/cpu/mtrr/generic.c:166: warning: Function parameter or member 'start' not described in 'mtrr_type_lookup_variable'
   arch/x86/kernel/cpu/mtrr/generic.c:166: warning: Function parameter or member 'end' not described in 'mtrr_type_lookup_variable'
   arch/x86/kernel/cpu/mtrr/generic.c:166: warning: Function parameter or member 'partial_end' not described in 'mtrr_type_lookup_variable'
   arch/x86/kernel/cpu/mtrr/generic.c:166: warning: Function parameter or member 'repeat' not described in 'mtrr_type_lookup_variable'
   arch/x86/kernel/cpu/mtrr/generic.c:166: warning: Function parameter or member 'uniform' not described in 'mtrr_type_lookup_variable'
>> arch/x86/kernel/cpu/mtrr/generic.c:259: warning: Function parameter or member 'var' not described in 'mtrr_overwrite_state'
>> arch/x86/kernel/cpu/mtrr/generic.c:259: warning: Function parameter or member 'num_var' not described in 'mtrr_overwrite_state'
>> arch/x86/kernel/cpu/mtrr/generic.c:259: warning: Function parameter or member 'def_type' not described in 'mtrr_overwrite_state'
   arch/x86/kernel/cpu/mtrr/generic.c:316: warning: Function parameter or member 'start' not described in 'mtrr_type_lookup'
   arch/x86/kernel/cpu/mtrr/generic.c:316: warning: Function parameter or member 'end' not described in 'mtrr_type_lookup'
   arch/x86/kernel/cpu/mtrr/generic.c:316: warning: Function parameter or member 'uniform' not described in 'mtrr_type_lookup'


vim +259 arch/x86/kernel/cpu/mtrr/generic.c

   246	
   247	/**
   248	 * mtrr_overwrite_state - set static MTRR state
   249	 *
   250	 * Used to set MTRR state via different means (e.g. with data obtained from
   251	 * a hypervisor).
   252	 * Is allowed only for special cases when running virtualized. Must be called
   253	 * from the x86_init.hyper.init_platform() hook.  It can be called only once.
   254	 * The MTRR state can't be changed afterwards.  To ensure that, X86_FEATURE_MTRR
   255	 * is cleared.
   256	 */
   257	void mtrr_overwrite_state(struct mtrr_var_range *var, unsigned int num_var,
   258				  mtrr_type def_type)
 > 259	{
   260		unsigned int i;
   261	
   262		/* Only allowed to be called once before mtrr_bp_init(). */
   263		if (WARN_ON_ONCE(mtrr_state_set))
   264			return;
   265	
   266		/* Only allowed when running virtualized. */
   267		if (!cpu_feature_enabled(X86_FEATURE_HYPERVISOR))
   268			return;
   269	
   270		/*
   271		 * Only allowed for special virtualization cases:
   272		 * - when running as Hyper-V, SEV-SNP guest using vTOM
   273		 * - when running as Xen PV guest
   274		 * - when running as SEV-SNP or TDX guest to avoid unnecessary
   275		 *   VMM communication/Virtualization exceptions (#VC, #VE)
   276		 */
   277		if (!cc_platform_has(CC_ATTR_GUEST_SEV_SNP) &&
   278		    !hv_is_isolation_supported() &&
   279		    !cpu_feature_enabled(X86_FEATURE_XENPV) &&
   280		    !cpu_feature_enabled(X86_FEATURE_TDX_GUEST))
   281			return;
   282	
   283		/* Disable MTRR in order to disable MTRR modifications. */
   284		setup_clear_cpu_cap(X86_FEATURE_MTRR);
   285	
   286		if (var) {
   287			if (num_var > MTRR_MAX_VAR_RANGES) {
   288				pr_warn("Trying to overwrite MTRR state with %u variable entries\n",
   289					num_var);
   290				num_var = MTRR_MAX_VAR_RANGES;
   291			}
   292			for (i = 0; i < num_var; i++)
   293				mtrr_state.var_ranges[i] = var[i];
   294			num_var_ranges = num_var;
   295		}
   296	
   297		mtrr_state.def_type = def_type;
   298		mtrr_state.enabled |= MTRR_STATE_MTRR_ENABLED;
   299	
   300		mtrr_state_set = 1;
   301	}
   302	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki