Re: [PATCH v13 05/15] iommu/smmuv3: Get prepared for nested stage support
From: kernel test robot
Date: Wed Nov 18 2020 - 23:01:08 EST
Hi Eric,
I love your patch! Perhaps something to improve:
[auto build test WARNING on iommu/next]
[also build test WARNING on linus/master v5.10-rc4 next-20201118]
[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/Eric-Auger/SMMUv3-Nested-Stage-Setup-IOMMU-part/20201118-192520
base: https://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu.git next
config: arm64-randconfig-s031-20201118 (attached as .config)
compiler: aarch64-linux-gcc (GCC) 9.3.0
reproduce:
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# apt-get install sparse
# sparse version: v0.6.3-123-g626c4742-dirty
# https://github.com/0day-ci/linux/commit/7308cdb07384d807c5ef43e6bfe0cd61c35a121e
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review Eric-Auger/SMMUv3-Nested-Stage-Setup-IOMMU-part/20201118-192520
git checkout 7308cdb07384d807c5ef43e6bfe0cd61c35a121e
# save the attached .config to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' ARCH=arm64
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@xxxxxxxxx>
"sparse warnings: (new ones prefixed by >>)"
>> drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c:1326:37: sparse: sparse: restricted __le64 degrades to integer
drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c:1326:37: sparse: sparse: cast to restricted __le64
drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c: note: in included file (through arch/arm64/include/asm/atomic.h, include/linux/atomic.h, include/asm-generic/bitops/atomic.h, ...):
arch/arm64/include/asm/cmpxchg.h:172:1: sparse: sparse: cast truncates bits from constant value (ffffffff80000000 becomes 0)
arch/arm64/include/asm/cmpxchg.h:172:1: sparse: sparse: cast truncates bits from constant value (ffffffff80000000 becomes 0)
vim +1326 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
1175
1176 static void arm_smmu_write_strtab_ent(struct arm_smmu_master *master, u32 sid,
1177 __le64 *dst)
1178 {
1179 /*
1180 * This is hideously complicated, but we only really care about
1181 * three cases at the moment:
1182 *
1183 * 1. Invalid (all zero) -> bypass/fault (init)
1184 * 2. Bypass/fault -> single stage translation/bypass (attach)
1185 * 3. Single or nested stage Translation/bypass -> bypass/fault (detach)
1186 * 4. S2 -> S1 + S2 (attach_pasid_table)
1187 * 5. S1 + S2 -> S2 (detach_pasid_table)
1188 *
1189 * Given that we can't update the STE atomically and the SMMU
1190 * doesn't read the thing in a defined order, that leaves us
1191 * with the following maintenance requirements:
1192 *
1193 * 1. Update Config, return (init time STEs aren't live)
1194 * 2. Write everything apart from dword 0, sync, write dword 0, sync
1195 * 3. Update Config, sync
1196 */
1197 u64 val = le64_to_cpu(dst[0]);
1198 bool s1_live = false, s2_live = false, ste_live;
1199 bool abort, nested = false, translate = false;
1200 struct arm_smmu_device *smmu = NULL;
1201 struct arm_smmu_s1_cfg *s1_cfg;
1202 struct arm_smmu_s2_cfg *s2_cfg;
1203 struct arm_smmu_domain *smmu_domain = NULL;
1204 struct arm_smmu_cmdq_ent prefetch_cmd = {
1205 .opcode = CMDQ_OP_PREFETCH_CFG,
1206 .prefetch = {
1207 .sid = sid,
1208 },
1209 };
1210
1211 if (master) {
1212 smmu_domain = master->domain;
1213 smmu = master->smmu;
1214 }
1215
1216 if (smmu_domain) {
1217 s1_cfg = &smmu_domain->s1_cfg;
1218 s2_cfg = &smmu_domain->s2_cfg;
1219
1220 switch (smmu_domain->stage) {
1221 case ARM_SMMU_DOMAIN_S1:
1222 s1_cfg->set = true;
1223 s2_cfg->set = false;
1224 break;
1225 case ARM_SMMU_DOMAIN_S2:
1226 s1_cfg->set = false;
1227 s2_cfg->set = true;
1228 break;
1229 case ARM_SMMU_DOMAIN_NESTED:
1230 /*
1231 * Actual usage of stage 1 depends on nested mode:
1232 * legacy (2d stage only) or true nested mode
1233 */
1234 s2_cfg->set = true;
1235 break;
1236 default:
1237 break;
1238 }
1239 nested = s1_cfg->set && s2_cfg->set;
1240 translate = s1_cfg->set || s2_cfg->set;
1241 }
1242
1243 if (val & STRTAB_STE_0_V) {
1244 switch (FIELD_GET(STRTAB_STE_0_CFG, val)) {
1245 case STRTAB_STE_0_CFG_BYPASS:
1246 break;
1247 case STRTAB_STE_0_CFG_S1_TRANS:
1248 s1_live = true;
1249 break;
1250 case STRTAB_STE_0_CFG_S2_TRANS:
1251 s2_live = true;
1252 break;
1253 case STRTAB_STE_0_CFG_NESTED:
1254 s1_live = true;
1255 s2_live = true;
1256 break;
1257 case STRTAB_STE_0_CFG_ABORT:
1258 break;
1259 default:
1260 BUG(); /* STE corruption */
1261 }
1262 }
1263
1264 ste_live = s1_live || s2_live;
1265
1266 /* Nuke the existing STE_0 value, as we're going to rewrite it */
1267 val = STRTAB_STE_0_V;
1268
1269 /* Bypass/fault */
1270
1271 if (!smmu_domain)
1272 abort = disable_bypass;
1273 else
1274 abort = smmu_domain->abort;
1275
1276 if (abort || !translate) {
1277 if (abort)
1278 val |= FIELD_PREP(STRTAB_STE_0_CFG, STRTAB_STE_0_CFG_ABORT);
1279 else
1280 val |= FIELD_PREP(STRTAB_STE_0_CFG, STRTAB_STE_0_CFG_BYPASS);
1281
1282 dst[0] = cpu_to_le64(val);
1283 dst[1] = cpu_to_le64(FIELD_PREP(STRTAB_STE_1_SHCFG,
1284 STRTAB_STE_1_SHCFG_INCOMING));
1285 dst[2] = 0; /* Nuke the VMID */
1286 /*
1287 * The SMMU can perform negative caching, so we must sync
1288 * the STE regardless of whether the old value was live.
1289 */
1290 if (smmu)
1291 arm_smmu_sync_ste_for_sid(smmu, sid);
1292 return;
1293 }
1294
1295 BUG_ON(ste_live && !nested);
1296
1297 if (ste_live) {
1298 /* First invalidate the live STE */
1299 dst[0] = cpu_to_le64(STRTAB_STE_0_CFG_ABORT);
1300 arm_smmu_sync_ste_for_sid(smmu, sid);
1301 }
1302
1303 if (s1_cfg->set) {
1304 BUG_ON(s1_live);
1305 dst[1] = cpu_to_le64(
1306 FIELD_PREP(STRTAB_STE_1_S1DSS, STRTAB_STE_1_S1DSS_SSID0) |
1307 FIELD_PREP(STRTAB_STE_1_S1CIR, STRTAB_STE_1_S1C_CACHE_WBRA) |
1308 FIELD_PREP(STRTAB_STE_1_S1COR, STRTAB_STE_1_S1C_CACHE_WBRA) |
1309 FIELD_PREP(STRTAB_STE_1_S1CSH, ARM_SMMU_SH_ISH) |
1310 FIELD_PREP(STRTAB_STE_1_STRW, STRTAB_STE_1_STRW_NSEL1));
1311
1312 if (smmu->features & ARM_SMMU_FEAT_STALLS &&
1313 !(smmu->features & ARM_SMMU_FEAT_STALL_FORCE))
1314 dst[1] |= cpu_to_le64(STRTAB_STE_1_S1STALLD);
1315
1316 val |= (s1_cfg->cdcfg.cdtab_dma & STRTAB_STE_0_S1CTXPTR_MASK) |
1317 FIELD_PREP(STRTAB_STE_0_CFG, STRTAB_STE_0_CFG_S1_TRANS) |
1318 FIELD_PREP(STRTAB_STE_0_S1CDMAX, s1_cfg->s1cdmax) |
1319 FIELD_PREP(STRTAB_STE_0_S1FMT, s1_cfg->s1fmt);
1320 }
1321
1322 if (s2_cfg->set) {
1323 u64 vttbr = s2_cfg->vttbr & STRTAB_STE_3_S2TTB_MASK;
1324
1325 if (s2_live) {
> 1326 u64 s2ttb = le64_to_cpu(dst[3] & STRTAB_STE_3_S2TTB_MASK);
1327
1328 BUG_ON(s2ttb != vttbr);
1329 }
1330
1331 dst[2] = cpu_to_le64(
1332 FIELD_PREP(STRTAB_STE_2_S2VMID, s2_cfg->vmid) |
1333 FIELD_PREP(STRTAB_STE_2_VTCR, s2_cfg->vtcr) |
1334 #ifdef __BIG_ENDIAN
1335 STRTAB_STE_2_S2ENDI |
1336 #endif
1337 STRTAB_STE_2_S2PTW | STRTAB_STE_2_S2AA64 |
1338 STRTAB_STE_2_S2R);
1339
1340 dst[3] = cpu_to_le64(vttbr);
1341
1342 val |= FIELD_PREP(STRTAB_STE_0_CFG, STRTAB_STE_0_CFG_S2_TRANS);
1343 } else {
1344 dst[2] = 0;
1345 dst[3] = 0;
1346 }
1347
1348 if (master->ats_enabled)
1349 dst[1] |= cpu_to_le64(FIELD_PREP(STRTAB_STE_1_EATS,
1350 STRTAB_STE_1_EATS_TRANS));
1351
1352 arm_smmu_sync_ste_for_sid(smmu, sid);
1353 /* See comment in arm_smmu_write_ctx_desc() */
1354 WRITE_ONCE(dst[0], cpu_to_le64(val));
1355 arm_smmu_sync_ste_for_sid(smmu, sid);
1356
1357 /* It's likely that we'll want to use the new STE soon */
1358 if (!(smmu->options & ARM_SMMU_OPT_SKIP_PREFETCH))
1359 arm_smmu_cmdq_issue_cmd(smmu, &prefetch_cmd);
1360 }
1361
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx
Attachment:
.config.gz
Description: application/gzip