Hi Vipin, [FYI, it's a private test report for your RFC patch.] [auto build test WARNING on kvm/linux-next] [also build test WARNING on vhost/linux-next linus/master cgroup/for-next v5.9-rc6 next-20200921] [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] url: https://github.com/0day-ci/linux/commits/Vipin-Sharma/KVM-SVM-Cgroup-supp... base: https://git.kernel.org/pub/scm/virt/kvm/kvm.git linux-next config: x86_64-allyesconfig (attached as .config) compiler: gcc-9 (Debian 9.3.0-15) 9.3.0 reproduce (this is a W=1 build): # save the attached .config to linux build tree make W=1 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 >>): 103 | int sev_asid_try_charge(int pos) | ^~~~~~~~~~~~~~~~~~~ 145 | void sev_asid_uncharge(int pos) | ^~~~~~~~~~~~~~~~~ 171 | int sev_cgroup_setup(unsigned int max) | ^~~~~~~~~~~~~~~~ 198 | void sev_cgroup_teardown(void) | ^~~~~~~~~~~~~~~~~~~ # https://github.com/0day-ci/linux/commit/a6ea9901dcea64e24118ff35965406ed1... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Vipin-Sharma/KVM-SVM-Cgroup-support-for-SVM-SEV-ASIDs/20200922-084116 git checkout a6ea9901dcea64e24118ff35965406ed101d614f vim +/sev_asid_try_charge +103 arch/x86/kvm/svm/sev_cgroup.c 88 89 /** 90 * sev_asid_try_charge() - Try charging an SEV ASID to the cgroup. 91 * @pos: Index of SEV ASID in the SEV ASIDs bitmap. 92 * 93 * Try charging an SEV ASID to the current task's cgroup and all its ancestors 94 * up to the root. If charging is not possible due to the limit constraint, 95 * then notify the event file and return -errorno. 96 * 97 * Context: Process context. Takes and release sev_cgroup_lock mutex. 98 * Return: 99 * * 0 - If successfully charged the cgroup. 100 * * -EINVAL - If pos is not valid. 101 * * -EBUSY - If usage has already reached the limit. 102 */ 104 { 105 struct sev_cgroup *start, *i, *j; 106 int ret = 0; 107 108 mutex_lock(&sev_cgroup_lock); 109 110 start = css_sev(task_css(current, sev_cgrp_id)); 111 112 for (i = start; i; i = parent_sev_cgroup(i)) { 113 if (i->usage == i->max) 114 goto e_limit; 115 116 i->usage++; 117 } 118 119 sev_asids_cgroup_array[pos] = start; 120 exit: 121 mutex_unlock(&sev_cgroup_lock); 122 return ret; 123 124 e_limit: 125 for (j = start; j != i; j = parent_sev_cgroup(j)) 126 sev_asid_cgroup_dec(j); 127 128 start->allocation_failure_event++; 129 cgroup_file_notify(&start->events_file); 130 131 ret = -EBUSY; 132 goto exit; 133 } 134 EXPORT_SYMBOL(sev_asid_try_charge); 135 136 /** 137 * sev_asid_uncharge() - Uncharge an SEV ASID from the cgroup. 138 * @pos: Index of SEV ASID in the SEV ASIDs bitmap. 139 * 140 * Uncharge an SEV ASID from the cgroup to which it was charged in 141 * sev_asid_try_charge(). 142 * 143 * Context: Process context. Takes and release sev_cgroup_lock mutex. 144 */ 146 { 147 struct sev_cgroup *i; 148 149 mutex_lock(&sev_cgroup_lock); 150 151 for (i = sev_asids_cgroup_array[pos]; i; i = parent_sev_cgroup(i)) 152 sev_asid_cgroup_dec(i); 153 154 sev_asids_cgroup_array[pos] = NULL; 155 156 mutex_unlock(&sev_cgroup_lock); 157 } 158 EXPORT_SYMBOL(sev_asid_uncharge); 159 160 /** 161 * sev_cgroup_setup() - Setup the sev cgroup before charging. 162 * @max: Maximum number of SEV ASIDs supported by the platform. 163 * 164 * Initialize the sev_asids_cgroup_array which stores ASID to cgroup mapping. 165 * 166 * Context: Process context. Takes and release sev_cgroup_lock mutex. 167 * Return: 168 * * 0 - If setup was successful. 169 * * -ENOMEM - If memory not available to allocate the array. 170 */ 172 { 173 int ret = 0; 174 175 mutex_lock(&sev_cgroup_lock); 176 177 sev_max_asids = max; 178 sev_asids_cgroup_array = kcalloc(sev_max_asids, 179 sizeof(struct sev_cgroup *), 180 GFP_KERNEL); 181 if (!sev_asids_cgroup_array) { 182 sev_max_asids = 0; 183 ret = -ENOMEM; 184 } 185 186 mutex_unlock(&sev_cgroup_lock); 187 188 return ret; 189 } 190 EXPORT_SYMBOL(sev_cgroup_setup); 191 192 /** 193 * sev_cgroup_teardown() - Release resources, no more charging/uncharging will 194 * happen. 195 * 196 * Context: Process context. Takes and release sev_cgroup_lock mutex. 197 */ 199 { 200 mutex_lock(&sev_cgroup_lock); 201 202 kfree(sev_asids_cgroup_array); 203 sev_asids_cgroup_array = NULL; 204 sev_max_asids = 0; 205 206 mutex_unlock(&sev_cgroup_lock); 207 } 208 EXPORT_SYMBOL(sev_cgroup_teardown); 209 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org