[avpatel:riscv_kvm_aia_v1 39/40] arch/riscv/kvm/aia_aplic.c:254:6: warning: variable 'inject' is used uninitialized whenever 'if' condition is true

From: kernel test robot
Date: Tue Dec 07 2021 - 19:11:21 EST


tree: https://github.com/avpatel/linux.git riscv_kvm_aia_v1
head: eb55ca3817a59020fc1e3d5a5de0a5adcebbedd0
commit: dc0299fdaf9714a56b13b955c086bab2f8bd4046 [39/40] RISC-V: KVM: Add in-kernel emulation of AIA APLIC
config: riscv-randconfig-c006-20211207 (https://download.01.org/0day-ci/archive/20211208/202112080820.BR1BIqGS-lkp@xxxxxxxxx/config)
compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project 097a1cb1d5ebb3a0ec4bcaed8ba3ff6a8e33c00a)
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# install riscv cross compiling tool for clang build
# apt-get install binutils-riscv64-linux-gnu
# https://github.com/avpatel/linux/commit/dc0299fdaf9714a56b13b955c086bab2f8bd4046
git remote add avpatel https://github.com/avpatel/linux.git
git fetch --no-tags avpatel riscv_kvm_aia_v1
git checkout dc0299fdaf9714a56b13b955c086bab2f8bd4046
# save the config file to linux build tree
mkdir build_dir
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=riscv SHELL=/bin/bash

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@xxxxxxxxx>

All warnings (new ones prefixed by >>):

>> arch/riscv/kvm/aia_aplic.c:254:6: warning: variable 'inject' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized]
if (irqd->sourcecfg & APLIC_SOURCECFG_D)
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
arch/riscv/kvm/aia_aplic.c:293:6: note: uninitialized use occurs here
if (inject)
^~~~~~
arch/riscv/kvm/aia_aplic.c:254:2: note: remove the 'if' if its condition is always false
if (irqd->sourcecfg & APLIC_SOURCECFG_D)
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
arch/riscv/kvm/aia_aplic.c:242:13: note: initialize the variable 'inject' to silence this warning
bool inject, ie;
^
= 0
1 warning generated.


vim +254 arch/riscv/kvm/aia_aplic.c

238
239 int kvm_riscv_aia_aplic_inject(struct kvm *kvm, u32 source, bool level)
240 {
241 u32 target;
242 bool inject, ie;
243 unsigned long flags;
244 struct aplic_irq *irqd;
245 struct aplic *aplic = kvm->arch.aia.aplic_state;
246
247 if (!aplic || !source || (aplic->nr_irqs <= source))
248 return -ENODEV;
249 irqd = &aplic->irqs[source];
250 ie = (aplic->domaincfg & APLIC_DOMAINCFG_IE) ? true : false;
251
252 raw_spin_lock_irqsave(&irqd->lock, flags);
253
> 254 if (irqd->sourcecfg & APLIC_SOURCECFG_D)
255 goto skip_unlock;
256
257 switch (irqd->sourcecfg & APLIC_SOURCECFG_SM_MASK) {
258 case APLIC_SOURCECFG_SM_EDGE_RISE:
259 if (level && !(irqd->state & APLIC_IRQ_STATE_INPUT) &&
260 !(irqd->state & APLIC_IRQ_STATE_PENDING))
261 irqd->state |= APLIC_IRQ_STATE_PENDING;
262 break;
263 case APLIC_SOURCECFG_SM_EDGE_FALL:
264 if (!level && (irqd->state & APLIC_IRQ_STATE_INPUT) &&
265 !(irqd->state & APLIC_IRQ_STATE_PENDING))
266 irqd->state |= APLIC_IRQ_STATE_PENDING;
267 break;
268 case APLIC_SOURCECFG_SM_LEVEL_HIGH:
269 if (level && !(irqd->state & APLIC_IRQ_STATE_PENDING))
270 irqd->state |= APLIC_IRQ_STATE_PENDING;
271 break;
272 case APLIC_SOURCECFG_SM_LEVEL_LOW:
273 if (!level && !(irqd->state & APLIC_IRQ_STATE_PENDING))
274 irqd->state |= APLIC_IRQ_STATE_PENDING;
275 break;
276 }
277
278 if (level)
279 irqd->state |= APLIC_IRQ_STATE_INPUT;
280 else
281 irqd->state &= ~APLIC_IRQ_STATE_INPUT;
282
283 inject = false;
284 target = irqd->target;
285 if (ie && (irqd->state & APLIC_IRQ_STATE_ENPEND)) {
286 irqd->state &= ~APLIC_IRQ_STATE_PENDING;
287 inject = true;
288 }
289
290 skip_unlock:
291 raw_spin_unlock_irqrestore(&irqd->lock, flags);
292
293 if (inject)
294 aplic_inject_msi(kvm, source, target);
295
296 return 0;
297 }
298

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx