Hi Srinivasan, I love your patch! Perhaps something to improve: [auto build test WARNING on v4.17-rc2] [also build test WARNING on next-20180426] [cannot apply to tip/x86/core] [if your patch is applied to the wrong git tree, please drop us a note to help improve the system] url: https://github.com/0day-ci/linux/commits/kys-linuxonhyperv-com/X86-Hyper-V-APIC-enlightenments/20180427-114416 reproduce: # apt-get install sparse make ARCH=x86_64 allmodconfig make C=1 CF=-D__CHECK_ENDIAN__ sparse warnings: (new ones prefixed by >>) >> arch/x86/hyperv/hv_init.c:105:30: sparse: incorrect type in initializer (different address spaces) @@ expected void const [noderef] <asn:3>*__vpp_verify @@ got const [noderef] <asn:3>*__vpp_verify @@ arch/x86/hyperv/hv_init.c:105:30: expected void const [noderef] <asn:3>*__vpp_verify arch/x86/hyperv/hv_init.c:105:30: got void [noderef] <asn:3>**<noident> arch/x86/hyperv/hv_init.c:229:30: sparse: incorrect type in initializer (different address spaces) @@ expected void const [noderef] <asn:3>*__vpp_verify @@ got const [noderef] <asn:3>*__vpp_verify @@ arch/x86/hyperv/hv_init.c:229:30: expected void const [noderef] <asn:3>*__vpp_verify arch/x86/hyperv/hv_init.c:229:30: got void [noderef] <asn:3>**<noident> >> arch/x86/hyperv/hv_init.c:275:31: sparse: incorrect type in assignment (different address spaces) @@ expected void [noderef] <asn:3>**extern [addressable] [toplevel] hyperv_pcpu_input_arg @@ got addressable] [toplevel] hyperv_pcpu_input_arg @@ arch/x86/hyperv/hv_init.c:275:31: expected void [noderef] <asn:3>**extern [addressable] [toplevel] hyperv_pcpu_input_arg arch/x86/hyperv/hv_init.c:275:31: got void *[noderef] <asn:3>*<noident> arch/x86/include/asm/paravirt.h:150:9: sparse: cast truncates bits from constant value (8000000000000000 becomes 0) -- >> arch/x86/hyperv/hv_apic.c:118:41: sparse: incorrect type in initializer (different address spaces) @@ expected void const [noderef] <asn:3>*__vpp_verify @@ got const [noderef] <asn:3>*__vpp_verify @@ arch/x86/hyperv/hv_apic.c:118:41: expected void const [noderef] <asn:3>*__vpp_verify arch/x86/hyperv/hv_apic.c:118:41: got void [noderef] <asn:3>**<noident> vim +105 arch/x86/hyperv/hv_init.c 98 99 static int hv_cpu_init(unsigned int cpu) 100 { 101 u64 msr_vp_index; 102 struct hv_vp_assist_page **hvp = &hv_vp_assist_page[smp_processor_id()]; 103 void **input_arg; 104 > 105 input_arg = (void **)this_cpu_ptr(hyperv_pcpu_input_arg); 106 *input_arg = page_address(alloc_page(GFP_ATOMIC)); 107 108 hv_get_vp_index(msr_vp_index); 109 110 hv_vp_index[smp_processor_id()] = msr_vp_index; 111 112 if (msr_vp_index > hv_max_vp_index) 113 hv_max_vp_index = msr_vp_index; 114 115 if (!hv_vp_assist_page) 116 return 0; 117 118 if (!*hvp) 119 *hvp = __vmalloc(PAGE_SIZE, GFP_KERNEL, PAGE_KERNEL); 120 121 if (*hvp) { 122 u64 val; 123 124 val = vmalloc_to_pfn(*hvp); 125 val = (val << HV_X64_MSR_VP_ASSIST_PAGE_ADDRESS_SHIFT) | 126 HV_X64_MSR_VP_ASSIST_PAGE_ENABLE; 127 128 wrmsrl(HV_X64_MSR_VP_ASSIST_PAGE, val); 129 } 130 131 return 0; 132 } 133 134 static void (*hv_reenlightenment_cb)(void); 135 136 static void hv_reenlightenment_notify(struct work_struct *dummy) 137 { 138 struct hv_tsc_emulation_status emu_status; 139 140 rdmsrl(HV_X64_MSR_TSC_EMULATION_STATUS, *(u64 *)&emu_status); 141 142 /* Don't issue the callback if TSC accesses are not emulated */ 143 if (hv_reenlightenment_cb && emu_status.inprogress) 144 hv_reenlightenment_cb(); 145 } 146 static DECLARE_DELAYED_WORK(hv_reenlightenment_work, hv_reenlightenment_notify); 147 148 void hyperv_stop_tsc_emulation(void) 149 { 150 u64 freq; 151 struct hv_tsc_emulation_status emu_status; 152 153 rdmsrl(HV_X64_MSR_TSC_EMULATION_STATUS, *(u64 *)&emu_status); 154 emu_status.inprogress = 0; 155 wrmsrl(HV_X64_MSR_TSC_EMULATION_STATUS, *(u64 *)&emu_status); 156 157 rdmsrl(HV_X64_MSR_TSC_FREQUENCY, freq); 158 tsc_khz = div64_u64(freq, 1000); 159 } 160 EXPORT_SYMBOL_GPL(hyperv_stop_tsc_emulation); 161 162 static inline bool hv_reenlightenment_available(void) 163 { 164 /* 165 * Check for required features and priviliges to make TSC frequency 166 * change notifications work. 167 */ 168 return ms_hyperv.features & HV_X64_ACCESS_FREQUENCY_MSRS && 169 ms_hyperv.misc_features & HV_FEATURE_FREQUENCY_MSRS_AVAILABLE && 170 ms_hyperv.features & HV_X64_ACCESS_REENLIGHTENMENT; 171 } 172 173 __visible void __irq_entry hyperv_reenlightenment_intr(struct pt_regs *regs) 174 { 175 entering_ack_irq(); 176 177 inc_irq_stat(irq_hv_reenlightenment_count); 178 179 schedule_delayed_work(&hv_reenlightenment_work, HZ/10); 180 181 exiting_irq(); 182 } 183 184 void set_hv_tscchange_cb(void (*cb)(void)) 185 { 186 struct hv_reenlightenment_control re_ctrl = { 187 .vector = HYPERV_REENLIGHTENMENT_VECTOR, 188 .enabled = 1, 189 .target_vp = hv_vp_index[smp_processor_id()] 190 }; 191 struct hv_tsc_emulation_control emu_ctrl = {.enabled = 1}; 192 193 if (!hv_reenlightenment_available()) { 194 pr_warn("Hyper-V: reenlightenment support is unavailable\n"); 195 return; 196 } 197 198 hv_reenlightenment_cb = cb; 199 200 /* Make sure callback is registered before we write to MSRs */ 201 wmb(); 202 203 wrmsrl(HV_X64_MSR_REENLIGHTENMENT_CONTROL, *((u64 *)&re_ctrl)); 204 wrmsrl(HV_X64_MSR_TSC_EMULATION_CONTROL, *((u64 *)&emu_ctrl)); 205 } 206 EXPORT_SYMBOL_GPL(set_hv_tscchange_cb); 207 208 void clear_hv_tscchange_cb(void) 209 { 210 struct hv_reenlightenment_control re_ctrl; 211 212 if (!hv_reenlightenment_available()) 213 return; 214 215 rdmsrl(HV_X64_MSR_REENLIGHTENMENT_CONTROL, *(u64 *)&re_ctrl); 216 re_ctrl.enabled = 0; 217 wrmsrl(HV_X64_MSR_REENLIGHTENMENT_CONTROL, *(u64 *)&re_ctrl); 218 219 hv_reenlightenment_cb = NULL; 220 } 221 EXPORT_SYMBOL_GPL(clear_hv_tscchange_cb); 222 223 static int hv_cpu_die(unsigned int cpu) 224 { 225 struct hv_reenlightenment_control re_ctrl; 226 unsigned int new_cpu; 227 void **input_arg; 228 229 input_arg = (void **)this_cpu_ptr(hyperv_pcpu_input_arg); 230 free_page((unsigned long)*input_arg); 231 232 if (hv_vp_assist_page && hv_vp_assist_page[cpu]) 233 wrmsrl(HV_X64_MSR_VP_ASSIST_PAGE, 0); 234 235 if (hv_reenlightenment_cb == NULL) 236 return 0; 237 238 rdmsrl(HV_X64_MSR_REENLIGHTENMENT_CONTROL, *((u64 *)&re_ctrl)); 239 if (re_ctrl.target_vp == hv_vp_index[cpu]) { 240 /* Reassign to some other online CPU */ 241 new_cpu = cpumask_any_but(cpu_online_mask, cpu); 242 243 re_ctrl.target_vp = hv_vp_index[new_cpu]; 244 wrmsrl(HV_X64_MSR_REENLIGHTENMENT_CONTROL, *((u64 *)&re_ctrl)); 245 } 246 247 return 0; 248 } 249 250 /* 251 * This function is to be invoked early in the boot sequence after the 252 * hypervisor has been detected. 253 * 254 * 1. Setup the hypercall page. 255 * 2. Register Hyper-V specific clocksource. 256 * 3. Setup Hyper-V specific APIC entry points. 257 */ 258 void __init hyperv_init(void) 259 { 260 u64 guest_id, required_msrs; 261 union hv_x64_msr_hypercall_contents hypercall_msr; 262 int cpuhp; 263 264 if (x86_hyper_type != X86_HYPER_MS_HYPERV) 265 return; 266 267 /* Absolutely required MSRs */ 268 required_msrs = HV_X64_MSR_HYPERCALL_AVAILABLE | 269 HV_X64_MSR_VP_INDEX_AVAILABLE; 270 271 if ((ms_hyperv.features & required_msrs) != required_msrs) 272 return; 273 274 /* Allocate the per-CPU state for the hypercall input arg */ > 275 hyperv_pcpu_input_arg = alloc_percpu(void *); 276 277 if (hyperv_pcpu_input_arg == NULL) 278 return; 279 280 /* Allocate percpu VP index */ 281 hv_vp_index = kmalloc_array(num_possible_cpus(), sizeof(*hv_vp_index), 282 GFP_KERNEL); 283 if (!hv_vp_index) 284 return; 285 286 hv_vp_assist_page = kcalloc(num_possible_cpus(), 287 sizeof(*hv_vp_assist_page), GFP_KERNEL); 288 if (!hv_vp_assist_page) { 289 ms_hyperv.hints &= ~HV_X64_ENLIGHTENED_VMCS_RECOMMENDED; 290 goto free_vp_index; 291 } 292 293 cpuhp = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "x86/hyperv_init:online", 294 hv_cpu_init, hv_cpu_die); 295 if (cpuhp < 0) 296 goto free_vp_assist_page; 297 298 /* 299 * Setup the hypercall page and enable hypercalls. 300 * 1. Register the guest ID 301 * 2. Enable the hypercall and register the hypercall page 302 */ 303 guest_id = generate_guest_id(0, LINUX_VERSION_CODE, 0); 304 wrmsrl(HV_X64_MSR_GUEST_OS_ID, guest_id); 305 306 hv_hypercall_pg = __vmalloc(PAGE_SIZE, GFP_KERNEL, PAGE_KERNEL_RX); 307 if (hv_hypercall_pg == NULL) { 308 wrmsrl(HV_X64_MSR_GUEST_OS_ID, 0); 309 goto remove_cpuhp_state; 310 } 311 312 rdmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64); 313 hypercall_msr.enable = 1; 314 hypercall_msr.guest_physical_address = vmalloc_to_pfn(hv_hypercall_pg); 315 wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64); 316 317 hyper_alloc_mmu(); 318 319 hv_apic_init(); 320 321 /* 322 * Register Hyper-V specific clocksource. 323 */ 324 #ifdef CONFIG_HYPERV_TSCPAGE 325 if (ms_hyperv.features & HV_X64_MSR_REFERENCE_TSC_AVAILABLE) { 326 union hv_x64_msr_hypercall_contents tsc_msr; 327 328 tsc_pg = __vmalloc(PAGE_SIZE, GFP_KERNEL, PAGE_KERNEL); 329 if (!tsc_pg) 330 goto register_msr_cs; 331 332 hyperv_cs = &hyperv_cs_tsc; 333 334 rdmsrl(HV_X64_MSR_REFERENCE_TSC, tsc_msr.as_uint64); 335 336 tsc_msr.enable = 1; 337 tsc_msr.guest_physical_address = vmalloc_to_pfn(tsc_pg); 338 339 wrmsrl(HV_X64_MSR_REFERENCE_TSC, tsc_msr.as_uint64); 340 341 hyperv_cs_tsc.archdata.vclock_mode = VCLOCK_HVCLOCK; 342 343 clocksource_register_hz(&hyperv_cs_tsc, NSEC_PER_SEC/100); 344 return; 345 } 346 register_msr_cs: 347 #endif 348 /* 349 * For 32 bit guests just use the MSR based mechanism for reading 350 * the partition counter. 351 */ 352 353 hyperv_cs = &hyperv_cs_msr; 354 if (ms_hyperv.features & HV_X64_MSR_TIME_REF_COUNT_AVAILABLE) 355 clocksource_register_hz(&hyperv_cs_msr, NSEC_PER_SEC/100); 356 357 return; 358 359 remove_cpuhp_state: 360 cpuhp_remove_state(cpuhp); 361 free_vp_assist_page: 362 kfree(hv_vp_assist_page); 363 hv_vp_assist_page = NULL; 364 free_vp_index: 365 kfree(hv_vp_index); 366 hv_vp_index = NULL; 367 } 368 --- 0-DAY kernel test infrastructure Open Source Technology Center https://lists.01.org/pipermail/kbuild-all Intel Corporation _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel