[kbuild-all] [intel-tdx:guest-upstream 25/33] arch/x86/mm/pat/set_memory.c:2012:6: warning: variable 'ret' set but not used

tree: https://github.com/intel/tdx.git guest-upstream head: 33b1329c49e6d5f961b29c5cafd6571a5de523f0 commit: 5364ea9ede9af9f08041cacf140f8feef077d375 [25/33] x86/mm/cpa: Add support for TDX shared memory config: x86_64-allyesconfig (https://download.01.org/0day-ci/archive/20220114/202201140659.QkMQQEy9-lk...) compiler: gcc-9 (Debian 9.3.0-22) 9.3.0 reproduce (this is a W=1 build): # https://github.com/intel/tdx/commit/5364ea9ede9af9f08041cacf140f8feef077d375 git remote add intel-tdx https://github.com/intel/tdx.git git fetch --no-tags intel-tdx guest-upstream git checkout 5364ea9ede9af9f08041cacf140f8feef077d375 # save the config file to linux build tree mkdir build_dir make W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash arch/x86/mm/pat/ 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/mm/pat/set_memory.c: In function '__set_memory_enc_pgtable': 2012 | int ret; | ^~~ vim +/ret +2012 arch/x86/mm/pat/set_memory.c 5364ea9ede9af9f arch/x86/mm/pat/set_memory.c Kirill A. Shutemov 2020-03-30 2004 810a521265023a1 arch/x86/mm/pat/set_memory.c Tianyu Lan 2021-10-25 2005 /* 810a521265023a1 arch/x86/mm/pat/set_memory.c Tianyu Lan 2021-10-25 2006 * __set_memory_enc_pgtable() is used for the hypervisors that get 810a521265023a1 arch/x86/mm/pat/set_memory.c Tianyu Lan 2021-10-25 2007 * informed about "encryption" status via page tables. 810a521265023a1 arch/x86/mm/pat/set_memory.c Tianyu Lan 2021-10-25 2008 */ 810a521265023a1 arch/x86/mm/pat/set_memory.c Tianyu Lan 2021-10-25 2009 static int __set_memory_enc_pgtable(unsigned long addr, int numpages, bool enc) 77bd2342d4304bd arch/x86/mm/pageattr.c Tom Lendacky 2017-07-17 2010 { 77bd2342d4304bd arch/x86/mm/pageattr.c Tom Lendacky 2017-07-17 2011 struct cpa_data cpa; 77bd2342d4304bd arch/x86/mm/pageattr.c Tom Lendacky 2017-07-17 @2012 int ret; 77bd2342d4304bd arch/x86/mm/pageattr.c Tom Lendacky 2017-07-17 2013 77bd2342d4304bd arch/x86/mm/pageattr.c Tom Lendacky 2017-07-17 2014 /* Should not be working on unaligned addresses */ 77bd2342d4304bd arch/x86/mm/pageattr.c Tom Lendacky 2017-07-17 2015 if (WARN_ONCE(addr & ~PAGE_MASK, "misaligned address: %#lx\n", addr)) 77bd2342d4304bd arch/x86/mm/pageattr.c Tom Lendacky 2017-07-17 2016 addr &= PAGE_MASK; 77bd2342d4304bd arch/x86/mm/pageattr.c Tom Lendacky 2017-07-17 2017 77bd2342d4304bd arch/x86/mm/pageattr.c Tom Lendacky 2017-07-17 2018 memset(&cpa, 0, sizeof(cpa)); 77bd2342d4304bd arch/x86/mm/pageattr.c Tom Lendacky 2017-07-17 2019 cpa.vaddr = &addr; 77bd2342d4304bd arch/x86/mm/pageattr.c Tom Lendacky 2017-07-17 2020 cpa.numpages = numpages; 5364ea9ede9af9f arch/x86/mm/pat/set_memory.c Kirill A. Shutemov 2020-03-30 2021 5364ea9ede9af9f arch/x86/mm/pat/set_memory.c Kirill A. Shutemov 2020-03-30 2022 cpa.mask_set = pgprot_cc_mask(enc); 5364ea9ede9af9f arch/x86/mm/pat/set_memory.c Kirill A. Shutemov 2020-03-30 2023 cpa.mask_clr = pgprot_cc_mask(!enc); 5364ea9ede9af9f arch/x86/mm/pat/set_memory.c Kirill A. Shutemov 2020-03-30 2024 77bd2342d4304bd arch/x86/mm/pageattr.c Tom Lendacky 2017-07-17 2025 cpa.pgd = init_mm.pgd; 77bd2342d4304bd arch/x86/mm/pageattr.c Tom Lendacky 2017-07-17 2026 77bd2342d4304bd arch/x86/mm/pageattr.c Tom Lendacky 2017-07-17 2027 /* Must avoid aliasing mappings in the highmem code */ 77bd2342d4304bd arch/x86/mm/pageattr.c Tom Lendacky 2017-07-17 2028 kmap_flush_unused(); 77bd2342d4304bd arch/x86/mm/pageattr.c Tom Lendacky 2017-07-17 2029 vm_unmap_aliases(); 77bd2342d4304bd arch/x86/mm/pageattr.c Tom Lendacky 2017-07-17 2030 77bd2342d4304bd arch/x86/mm/pageattr.c Tom Lendacky 2017-07-17 2031 /* 5364ea9ede9af9f arch/x86/mm/pat/set_memory.c Kirill A. Shutemov 2020-03-30 2032 * Before changing the encryption attribute, flush caches. 5364ea9ede9af9f arch/x86/mm/pat/set_memory.c Kirill A. Shutemov 2020-03-30 2033 * 5364ea9ede9af9f arch/x86/mm/pat/set_memory.c Kirill A. Shutemov 2020-03-30 2034 * For TDX, guest is responsible for flushing caches on private->shared 5364ea9ede9af9f arch/x86/mm/pat/set_memory.c Kirill A. Shutemov 2020-03-30 2035 * transition. VMM is responsible for flushing on shared->private. 77bd2342d4304bd arch/x86/mm/pageattr.c Tom Lendacky 2017-07-17 2036 */ 5364ea9ede9af9f arch/x86/mm/pat/set_memory.c Kirill A. Shutemov 2020-03-30 2037 if (cc_platform_has(CC_ATTR_GUEST_TDX)) { 5364ea9ede9af9f arch/x86/mm/pat/set_memory.c Kirill A. Shutemov 2020-03-30 2038 if (!enc) 5364ea9ede9af9f arch/x86/mm/pat/set_memory.c Kirill A. Shutemov 2020-03-30 2039 cpa_flush(&cpa, 1); 5364ea9ede9af9f arch/x86/mm/pat/set_memory.c Kirill A. Shutemov 2020-03-30 2040 } else { 75d1cc0e05af579 arch/x86/mm/pat/set_memory.c Krish Sadhukhan 2020-09-17 2041 cpa_flush(&cpa, !this_cpu_has(X86_FEATURE_SME_COHERENT)); 5364ea9ede9af9f arch/x86/mm/pat/set_memory.c Kirill A. Shutemov 2020-03-30 2042 } 77bd2342d4304bd arch/x86/mm/pageattr.c Tom Lendacky 2017-07-17 2043 77bd2342d4304bd arch/x86/mm/pageattr.c Tom Lendacky 2017-07-17 2044 ret = __change_page_attr_set_clr(&cpa, 1); 77bd2342d4304bd arch/x86/mm/pageattr.c Tom Lendacky 2017-07-17 2045 77bd2342d4304bd arch/x86/mm/pageattr.c Tom Lendacky 2017-07-17 2046 /* fe0937b24ff5d7b arch/x86/mm/pageattr.c Peter Zijlstra 2018-12-03 2047 * After changing the encryption attribute, we need to flush TLBs again fe0937b24ff5d7b arch/x86/mm/pageattr.c Peter Zijlstra 2018-12-03 2048 * in case any speculative TLB caching occurred (but no need to flush fe0937b24ff5d7b arch/x86/mm/pageattr.c Peter Zijlstra 2018-12-03 2049 * caches again). We could just use cpa_flush_all(), but in case TLB fe0937b24ff5d7b arch/x86/mm/pageattr.c Peter Zijlstra 2018-12-03 2050 * flushing gets optimized in the cpa_flush() path use the same logic fe0937b24ff5d7b arch/x86/mm/pageattr.c Peter Zijlstra 2018-12-03 2051 * as above. 77bd2342d4304bd arch/x86/mm/pageattr.c Tom Lendacky 2017-07-17 2052 */ fe0937b24ff5d7b arch/x86/mm/pageattr.c Peter Zijlstra 2018-12-03 2053 cpa_flush(&cpa, 0); 77bd2342d4304bd arch/x86/mm/pageattr.c Tom Lendacky 2017-07-17 2054 064ce6c550a0630 arch/x86/mm/pat/set_memory.c Brijesh Singh 2021-08-24 2055 /* 064ce6c550a0630 arch/x86/mm/pat/set_memory.c Brijesh Singh 2021-08-24 2056 * Notify hypervisor that a given memory range is mapped encrypted 064ce6c550a0630 arch/x86/mm/pat/set_memory.c Brijesh Singh 2021-08-24 2057 * or decrypted. 064ce6c550a0630 arch/x86/mm/pat/set_memory.c Brijesh Singh 2021-08-24 2058 */ 5364ea9ede9af9f arch/x86/mm/pat/set_memory.c Kirill A. Shutemov 2020-03-30 2059 return notify_range_enc_status_changed(addr, numpages, enc); 77bd2342d4304bd arch/x86/mm/pageattr.c Tom Lendacky 2017-07-17 2060 } 77bd2342d4304bd arch/x86/mm/pageattr.c Tom Lendacky 2017-07-17 2061 :::::: The code at line 2012 was first introduced by commit :::::: 77bd2342d4304bda7896c953d424d15deb314ca3 x86/mm: Add support for changing the memory encryption attribute :::::: TO: Tom Lendacky <thomas.lendacky(a)amd.com&gt; :::::: CC: Ingo Molnar <mingo(a)kernel.org&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org