[kvm:queue 71/177] arch/x86/kvm/vmx/nested.c:5246:3: error: variable 'roots_to_free' is used uninitialized whenever 'if' condition is false
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kbuild test robot
May 16, 2020, 11:39:03 AM5/16/20
to Sean Christopherson, kbuil...@lists.01.org, clang-bu...@googlegroups.com, k...@vger.kernel.org, Robert Hu, Farrah Chen, Danmei Wei, Paolo Bonzini
tree: https://git.kernel.org/pub/scm/virt/kvm/kvm.git queue
head: cb953129bfe5c0f2da835a0469930873fb7e71df
commit: ce8fe7b77bd8ee405295e349c82d0ef8c9788200 [71/177] KVM: nVMX: Free only the affected contexts when emulating INVEPT
config: x86_64-randconfig-a012-20200515 (attached as .config)
compiler: clang version 11.0.0 (https://github.com/llvm/llvm-project 13d44b2a0c7ef404b13b16644765977cd5310fe2)
reproduce:
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# install x86_64 cross compiling tool for clang build
# apt-get install binutils-x86-64-linux-gnu
git checkout ce8fe7b77bd8ee405295e349c82d0ef8c9788200
# save the attached .config to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64
If you fix the issue, kindly add following tag as appropriate
Reported-by: kbuild test robot <l...@intel.com>
Note: the kvm/queue HEAD cb953129bfe5c0f2da835a0469930873fb7e71df builds fine.
It only hurts bisectibility.
All errors (new ones prefixed by >>, old ones prefixed by <<):
>> arch/x86/kvm/vmx/nested.c:5246:3: error: variable 'roots_to_free' is used uninitialized whenever 'if' condition is false [-Werror,-Wsometimes-uninitialized]
BUG_ON(1);
^~~~~~~~~
include/asm-generic/bug.h:62:32: note: expanded from macro 'BUG_ON'
#define BUG_ON(condition) do { if (unlikely(condition)) BUG(); } while (0)
^~~~~~~~~~~~~~~~~~~~~~~~
include/linux/compiler.h:56:28: note: expanded from macro 'if'
#define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/compiler.h:58:30: note: expanded from macro '__trace_if_var'
#define __trace_if_var(cond) (__builtin_constant_p(cond) ? (cond) : __trace_if_value(cond))
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
arch/x86/kvm/vmx/nested.c:5250:6: note: uninitialized use occurs here
if (roots_to_free)
^~~~~~~~~~~~~
include/linux/compiler.h:56:47: note: expanded from macro 'if'
#define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
^~~~
include/linux/compiler.h:58:52: note: expanded from macro '__trace_if_var'
#define __trace_if_var(cond) (__builtin_constant_p(cond) ? (cond) : __trace_if_value(cond))
^~~~
arch/x86/kvm/vmx/nested.c:5246:3: note: remove the 'if' if its condition is always true
BUG_ON(1);
^
include/asm-generic/bug.h:62:32: note: expanded from macro 'BUG_ON'
#define BUG_ON(condition) do { if (unlikely(condition)) BUG(); } while (0)
^
include/linux/compiler.h:56:23: note: expanded from macro 'if'
#define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
^
arch/x86/kvm/vmx/nested.c:5179:35: note: initialize the variable 'roots_to_free' to silence this warning
unsigned long type, roots_to_free;
^
= 0
1 error generated.
vim +5246 arch/x86/kvm/vmx/nested.c
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5173
55d2375e58a61b Sean Christopherson 2018-12-03 5174 /* Emulate the INVEPT instruction */
55d2375e58a61b Sean Christopherson 2018-12-03 5175 static int handle_invept(struct kvm_vcpu *vcpu)
55d2375e58a61b Sean Christopherson 2018-12-03 5176 {
55d2375e58a61b Sean Christopherson 2018-12-03 5177 struct vcpu_vmx *vmx = to_vmx(vcpu);
55d2375e58a61b Sean Christopherson 2018-12-03 5178 u32 vmx_instruction_info, types;
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5179 unsigned long type, roots_to_free;
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5180 struct kvm_mmu *mmu;
55d2375e58a61b Sean Christopherson 2018-12-03 5181 gva_t gva;
55d2375e58a61b Sean Christopherson 2018-12-03 5182 struct x86_exception e;
55d2375e58a61b Sean Christopherson 2018-12-03 5183 struct {
55d2375e58a61b Sean Christopherson 2018-12-03 5184 u64 eptp, gpa;
55d2375e58a61b Sean Christopherson 2018-12-03 5185 } operand;
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5186 int i;
55d2375e58a61b Sean Christopherson 2018-12-03 5187
55d2375e58a61b Sean Christopherson 2018-12-03 5188 if (!(vmx->nested.msrs.secondary_ctls_high &
55d2375e58a61b Sean Christopherson 2018-12-03 5189 SECONDARY_EXEC_ENABLE_EPT) ||
55d2375e58a61b Sean Christopherson 2018-12-03 5190 !(vmx->nested.msrs.ept_caps & VMX_EPT_INVEPT_BIT)) {
55d2375e58a61b Sean Christopherson 2018-12-03 5191 kvm_queue_exception(vcpu, UD_VECTOR);
55d2375e58a61b Sean Christopherson 2018-12-03 5192 return 1;
55d2375e58a61b Sean Christopherson 2018-12-03 5193 }
55d2375e58a61b Sean Christopherson 2018-12-03 5194
55d2375e58a61b Sean Christopherson 2018-12-03 5195 if (!nested_vmx_check_permission(vcpu))
55d2375e58a61b Sean Christopherson 2018-12-03 5196 return 1;
55d2375e58a61b Sean Christopherson 2018-12-03 5197
55d2375e58a61b Sean Christopherson 2018-12-03 5198 vmx_instruction_info = vmcs_read32(VMX_INSTRUCTION_INFO);
55d2375e58a61b Sean Christopherson 2018-12-03 5199 type = kvm_register_readl(vcpu, (vmx_instruction_info >> 28) & 0xf);
55d2375e58a61b Sean Christopherson 2018-12-03 5200
55d2375e58a61b Sean Christopherson 2018-12-03 5201 types = (vmx->nested.msrs.ept_caps >> VMX_EPT_EXTENT_SHIFT) & 6;
55d2375e58a61b Sean Christopherson 2018-12-03 5202
55d2375e58a61b Sean Christopherson 2018-12-03 5203 if (type >= 32 || !(types & (1 << type)))
55d2375e58a61b Sean Christopherson 2018-12-03 5204 return nested_vmx_failValid(vcpu,
55d2375e58a61b Sean Christopherson 2018-12-03 5205 VMXERR_INVALID_OPERAND_TO_INVEPT_INVVPID);
55d2375e58a61b Sean Christopherson 2018-12-03 5206
55d2375e58a61b Sean Christopherson 2018-12-03 5207 /* According to the Intel VMX instruction reference, the memory
55d2375e58a61b Sean Christopherson 2018-12-03 5208 * operand is read even if it isn't needed (e.g., for type==global)
55d2375e58a61b Sean Christopherson 2018-12-03 5209 */
55d2375e58a61b Sean Christopherson 2018-12-03 5210 if (get_vmx_mem_address(vcpu, vmcs_readl(EXIT_QUALIFICATION),
fdb28619a8f033 Eugene Korenevsky 2019-06-06 5211 vmx_instruction_info, false, sizeof(operand), &gva))
55d2375e58a61b Sean Christopherson 2018-12-03 5212 return 1;
55d2375e58a61b Sean Christopherson 2018-12-03 5213 if (kvm_read_guest_virt(vcpu, gva, &operand, sizeof(operand), &e)) {
ee1fa209f5e5ca Junaid Shahid 2020-03-20 5214 kvm_inject_emulated_page_fault(vcpu, &e);
55d2375e58a61b Sean Christopherson 2018-12-03 5215 return 1;
55d2375e58a61b Sean Christopherson 2018-12-03 5216 }
55d2375e58a61b Sean Christopherson 2018-12-03 5217
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5218 /*
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5219 * Nested EPT roots are always held through guest_mmu,
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5220 * not root_mmu.
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5221 */
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5222 mmu = &vcpu->arch.guest_mmu;
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5223
55d2375e58a61b Sean Christopherson 2018-12-03 5224 switch (type) {
b119019847fbca Jim Mattson 2019-06-13 5225 case VMX_EPT_EXTENT_CONTEXT:
eed0030e4caa94 Sean Christopherson 2020-03-20 5226 if (!nested_vmx_check_eptp(vcpu, operand.eptp))
eed0030e4caa94 Sean Christopherson 2020-03-20 5227 return nested_vmx_failValid(vcpu,
eed0030e4caa94 Sean Christopherson 2020-03-20 5228 VMXERR_INVALID_OPERAND_TO_INVEPT_INVVPID);
f8aa7e3958bc43 Sean Christopherson 2020-03-20 5229
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5230 roots_to_free = 0;
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5231 if (nested_ept_root_matches(mmu->root_hpa, mmu->root_cr3,
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5232 operand.eptp))
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5233 roots_to_free |= KVM_MMU_ROOT_CURRENT;
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5234
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5235 for (i = 0; i < KVM_MMU_NUM_PREV_ROOTS; i++) {
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5236 if (nested_ept_root_matches(mmu->prev_roots[i].hpa,
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5237 mmu->prev_roots[i].cr3,
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5238 operand.eptp))
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5239 roots_to_free |= KVM_MMU_ROOT_PREVIOUS(i);
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5240 }
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5241 break;
eed0030e4caa94 Sean Christopherson 2020-03-20 5242 case VMX_EPT_EXTENT_GLOBAL:
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5243 roots_to_free = KVM_MMU_ROOTS_ALL;
55d2375e58a61b Sean Christopherson 2018-12-03 5244 break;
55d2375e58a61b Sean Christopherson 2018-12-03 5245 default:
55d2375e58a61b Sean Christopherson 2018-12-03 @5246 BUG_ON(1);
55d2375e58a61b Sean Christopherson 2018-12-03 5247 break;
55d2375e58a61b Sean Christopherson 2018-12-03 5248 }
55d2375e58a61b Sean Christopherson 2018-12-03 5249
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5250 if (roots_to_free)
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5251 kvm_mmu_free_roots(vcpu, mmu, roots_to_free);
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5252
55d2375e58a61b Sean Christopherson 2018-12-03 5253 return nested_vmx_succeed(vcpu);
55d2375e58a61b Sean Christopherson 2018-12-03 5254 }
55d2375e58a61b Sean Christopherson 2018-12-03 5255
:::::: The code at line 5246 was first introduced by commit
:::::: 55d2375e58a61be072431dd3d3c8a320f4a4a01b KVM: nVMX: Move nested code to dedicated files
:::::: TO: Sean Christopherson <sean.j.chr...@intel.com>
:::::: CC: Paolo Bonzini <pbon...@redhat.com>
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuil...@lists.01.org
head: cb953129bfe5c0f2da835a0469930873fb7e71df
commit: ce8fe7b77bd8ee405295e349c82d0ef8c9788200 [71/177] KVM: nVMX: Free only the affected contexts when emulating INVEPT
config: x86_64-randconfig-a012-20200515 (attached as .config)
compiler: clang version 11.0.0 (https://github.com/llvm/llvm-project 13d44b2a0c7ef404b13b16644765977cd5310fe2)
reproduce:
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# install x86_64 cross compiling tool for clang build
# apt-get install binutils-x86-64-linux-gnu
git checkout ce8fe7b77bd8ee405295e349c82d0ef8c9788200
# save the attached .config to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64
If you fix the issue, kindly add following tag as appropriate
Reported-by: kbuild test robot <l...@intel.com>
Note: the kvm/queue HEAD cb953129bfe5c0f2da835a0469930873fb7e71df builds fine.
It only hurts bisectibility.
All errors (new ones prefixed by >>, old ones prefixed by <<):
>> arch/x86/kvm/vmx/nested.c:5246:3: error: variable 'roots_to_free' is used uninitialized whenever 'if' condition is false [-Werror,-Wsometimes-uninitialized]
BUG_ON(1);
^~~~~~~~~
include/asm-generic/bug.h:62:32: note: expanded from macro 'BUG_ON'
#define BUG_ON(condition) do { if (unlikely(condition)) BUG(); } while (0)
^~~~~~~~~~~~~~~~~~~~~~~~
include/linux/compiler.h:56:28: note: expanded from macro 'if'
#define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/compiler.h:58:30: note: expanded from macro '__trace_if_var'
#define __trace_if_var(cond) (__builtin_constant_p(cond) ? (cond) : __trace_if_value(cond))
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
arch/x86/kvm/vmx/nested.c:5250:6: note: uninitialized use occurs here
if (roots_to_free)
^~~~~~~~~~~~~
include/linux/compiler.h:56:47: note: expanded from macro 'if'
#define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
^~~~
include/linux/compiler.h:58:52: note: expanded from macro '__trace_if_var'
#define __trace_if_var(cond) (__builtin_constant_p(cond) ? (cond) : __trace_if_value(cond))
^~~~
arch/x86/kvm/vmx/nested.c:5246:3: note: remove the 'if' if its condition is always true
BUG_ON(1);
^
include/asm-generic/bug.h:62:32: note: expanded from macro 'BUG_ON'
#define BUG_ON(condition) do { if (unlikely(condition)) BUG(); } while (0)
^
include/linux/compiler.h:56:23: note: expanded from macro 'if'
#define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
^
arch/x86/kvm/vmx/nested.c:5179:35: note: initialize the variable 'roots_to_free' to silence this warning
unsigned long type, roots_to_free;
^
= 0
1 error generated.
vim +5246 arch/x86/kvm/vmx/nested.c
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5173
55d2375e58a61b Sean Christopherson 2018-12-03 5174 /* Emulate the INVEPT instruction */
55d2375e58a61b Sean Christopherson 2018-12-03 5175 static int handle_invept(struct kvm_vcpu *vcpu)
55d2375e58a61b Sean Christopherson 2018-12-03 5176 {
55d2375e58a61b Sean Christopherson 2018-12-03 5177 struct vcpu_vmx *vmx = to_vmx(vcpu);
55d2375e58a61b Sean Christopherson 2018-12-03 5178 u32 vmx_instruction_info, types;
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5179 unsigned long type, roots_to_free;
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5180 struct kvm_mmu *mmu;
55d2375e58a61b Sean Christopherson 2018-12-03 5181 gva_t gva;
55d2375e58a61b Sean Christopherson 2018-12-03 5182 struct x86_exception e;
55d2375e58a61b Sean Christopherson 2018-12-03 5183 struct {
55d2375e58a61b Sean Christopherson 2018-12-03 5184 u64 eptp, gpa;
55d2375e58a61b Sean Christopherson 2018-12-03 5185 } operand;
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5186 int i;
55d2375e58a61b Sean Christopherson 2018-12-03 5187
55d2375e58a61b Sean Christopherson 2018-12-03 5188 if (!(vmx->nested.msrs.secondary_ctls_high &
55d2375e58a61b Sean Christopherson 2018-12-03 5189 SECONDARY_EXEC_ENABLE_EPT) ||
55d2375e58a61b Sean Christopherson 2018-12-03 5190 !(vmx->nested.msrs.ept_caps & VMX_EPT_INVEPT_BIT)) {
55d2375e58a61b Sean Christopherson 2018-12-03 5191 kvm_queue_exception(vcpu, UD_VECTOR);
55d2375e58a61b Sean Christopherson 2018-12-03 5192 return 1;
55d2375e58a61b Sean Christopherson 2018-12-03 5193 }
55d2375e58a61b Sean Christopherson 2018-12-03 5194
55d2375e58a61b Sean Christopherson 2018-12-03 5195 if (!nested_vmx_check_permission(vcpu))
55d2375e58a61b Sean Christopherson 2018-12-03 5196 return 1;
55d2375e58a61b Sean Christopherson 2018-12-03 5197
55d2375e58a61b Sean Christopherson 2018-12-03 5198 vmx_instruction_info = vmcs_read32(VMX_INSTRUCTION_INFO);
55d2375e58a61b Sean Christopherson 2018-12-03 5199 type = kvm_register_readl(vcpu, (vmx_instruction_info >> 28) & 0xf);
55d2375e58a61b Sean Christopherson 2018-12-03 5200
55d2375e58a61b Sean Christopherson 2018-12-03 5201 types = (vmx->nested.msrs.ept_caps >> VMX_EPT_EXTENT_SHIFT) & 6;
55d2375e58a61b Sean Christopherson 2018-12-03 5202
55d2375e58a61b Sean Christopherson 2018-12-03 5203 if (type >= 32 || !(types & (1 << type)))
55d2375e58a61b Sean Christopherson 2018-12-03 5204 return nested_vmx_failValid(vcpu,
55d2375e58a61b Sean Christopherson 2018-12-03 5205 VMXERR_INVALID_OPERAND_TO_INVEPT_INVVPID);
55d2375e58a61b Sean Christopherson 2018-12-03 5206
55d2375e58a61b Sean Christopherson 2018-12-03 5207 /* According to the Intel VMX instruction reference, the memory
55d2375e58a61b Sean Christopherson 2018-12-03 5208 * operand is read even if it isn't needed (e.g., for type==global)
55d2375e58a61b Sean Christopherson 2018-12-03 5209 */
55d2375e58a61b Sean Christopherson 2018-12-03 5210 if (get_vmx_mem_address(vcpu, vmcs_readl(EXIT_QUALIFICATION),
fdb28619a8f033 Eugene Korenevsky 2019-06-06 5211 vmx_instruction_info, false, sizeof(operand), &gva))
55d2375e58a61b Sean Christopherson 2018-12-03 5212 return 1;
55d2375e58a61b Sean Christopherson 2018-12-03 5213 if (kvm_read_guest_virt(vcpu, gva, &operand, sizeof(operand), &e)) {
ee1fa209f5e5ca Junaid Shahid 2020-03-20 5214 kvm_inject_emulated_page_fault(vcpu, &e);
55d2375e58a61b Sean Christopherson 2018-12-03 5215 return 1;
55d2375e58a61b Sean Christopherson 2018-12-03 5216 }
55d2375e58a61b Sean Christopherson 2018-12-03 5217
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5218 /*
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5219 * Nested EPT roots are always held through guest_mmu,
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5220 * not root_mmu.
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5221 */
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5222 mmu = &vcpu->arch.guest_mmu;
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5223
55d2375e58a61b Sean Christopherson 2018-12-03 5224 switch (type) {
b119019847fbca Jim Mattson 2019-06-13 5225 case VMX_EPT_EXTENT_CONTEXT:
eed0030e4caa94 Sean Christopherson 2020-03-20 5226 if (!nested_vmx_check_eptp(vcpu, operand.eptp))
eed0030e4caa94 Sean Christopherson 2020-03-20 5227 return nested_vmx_failValid(vcpu,
eed0030e4caa94 Sean Christopherson 2020-03-20 5228 VMXERR_INVALID_OPERAND_TO_INVEPT_INVVPID);
f8aa7e3958bc43 Sean Christopherson 2020-03-20 5229
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5230 roots_to_free = 0;
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5231 if (nested_ept_root_matches(mmu->root_hpa, mmu->root_cr3,
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5232 operand.eptp))
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5233 roots_to_free |= KVM_MMU_ROOT_CURRENT;
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5234
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5235 for (i = 0; i < KVM_MMU_NUM_PREV_ROOTS; i++) {
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5236 if (nested_ept_root_matches(mmu->prev_roots[i].hpa,
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5237 mmu->prev_roots[i].cr3,
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5238 operand.eptp))
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5239 roots_to_free |= KVM_MMU_ROOT_PREVIOUS(i);
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5240 }
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5241 break;
eed0030e4caa94 Sean Christopherson 2020-03-20 5242 case VMX_EPT_EXTENT_GLOBAL:
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5243 roots_to_free = KVM_MMU_ROOTS_ALL;
55d2375e58a61b Sean Christopherson 2018-12-03 5244 break;
55d2375e58a61b Sean Christopherson 2018-12-03 5245 default:
55d2375e58a61b Sean Christopherson 2018-12-03 @5246 BUG_ON(1);
55d2375e58a61b Sean Christopherson 2018-12-03 5247 break;
55d2375e58a61b Sean Christopherson 2018-12-03 5248 }
55d2375e58a61b Sean Christopherson 2018-12-03 5249
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5250 if (roots_to_free)
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5251 kvm_mmu_free_roots(vcpu, mmu, roots_to_free);
ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5252
55d2375e58a61b Sean Christopherson 2018-12-03 5253 return nested_vmx_succeed(vcpu);
55d2375e58a61b Sean Christopherson 2018-12-03 5254 }
55d2375e58a61b Sean Christopherson 2018-12-03 5255
:::::: The code at line 5246 was first introduced by commit
:::::: 55d2375e58a61be072431dd3d3c8a320f4a4a01b KVM: nVMX: Move nested code to dedicated files
:::::: TO: Sean Christopherson <sean.j.chr...@intel.com>
:::::: CC: Paolo Bonzini <pbon...@redhat.com>
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuil...@lists.01.org
Nick Desaulniers
May 18, 2020, 3:16:15 PM5/18/20
to kbuild test robot, Sean Christopherson, kbuil...@lists.01.org, clang-built-linux, kvm, Robert Hu, Farrah Chen, Danmei Wei, Paolo Bonzini
> ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5231 if (nested_ept_root_matches(mmu->root_hpa, mmu->root_cr3,
> ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5232 operand.eptp))
> ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5233 roots_to_free |= KVM_MMU_ROOT_CURRENT;
> ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5234
> ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5235 for (i = 0; i < KVM_MMU_NUM_PREV_ROOTS; i++) {
> ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5236 if (nested_ept_root_matches(mmu->prev_roots[i].hpa,
> ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5237 mmu->prev_roots[i].cr3,
> ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5238 operand.eptp))
> ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5239 roots_to_free |= KVM_MMU_ROOT_PREVIOUS(i);
> ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5240 }
> ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5241 break;
> eed0030e4caa94 Sean Christopherson 2020-03-20 5242 case VMX_EPT_EXTENT_GLOBAL:
> ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5243 roots_to_free = KVM_MMU_ROOTS_ALL;
> 55d2375e58a61b Sean Christopherson 2018-12-03 5244 break;
> 55d2375e58a61b Sean Christopherson 2018-12-03 5245 default:
> 55d2375e58a61b Sean Christopherson 2018-12-03 @5246 BUG_ON(1);
> 55d2375e58a61b Sean Christopherson 2018-12-03 5247 break;
> 55d2375e58a61b Sean Christopherson 2018-12-03 5248 }
> 55d2375e58a61b Sean Christopherson 2018-12-03 5249
> ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5250 if (roots_to_free)
While the BUG_ON in the default case should prevent the problematic
use, Clang can't understand the semantics of BUG_ON. roots_to_free
should just be initialized to zero.
> ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5251 kvm_mmu_free_roots(vcpu, mmu, roots_to_free);
> ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5252
> 55d2375e58a61b Sean Christopherson 2018-12-03 5253 return nested_vmx_succeed(vcpu);
> 55d2375e58a61b Sean Christopherson 2018-12-03 5254 }
> 55d2375e58a61b Sean Christopherson 2018-12-03 5255
>
> :::::: The code at line 5246 was first introduced by commit
> :::::: 55d2375e58a61be072431dd3d3c8a320f4a4a01b KVM: nVMX: Move nested code to dedicated files
>
> :::::: TO: Sean Christopherson <sean.j.chr...@intel.com>
> :::::: CC: Paolo Bonzini <pbon...@redhat.com>
>
> ---
> 0-DAY CI Kernel Test Service, Intel Corporation
> https://lists.01.org/hyperkitty/list/kbuil...@lists.01.org
>
> You received this message because you are subscribed to the Google Groups "Clang Built Linux" group.
> To unsubscribe from this group and stop receiving emails from it, send an email to clang-built-li...@googlegroups.com.
> To view this discussion on the web visit https://groups.google.com/d/msgid/clang-built-linux/202005162313.CDreQC6s%25lkp%40intel.com.
--
Thanks,
~Nick Desaulniers
Nathan Chancellor
May 18, 2020, 3:18:48 PM5/18/20
to Nick Desaulniers, kbuild test robot, Sean Christopherson, kbuil...@lists.01.org, clang-built-linux, kvm, Robert Hu, Farrah Chen, Danmei Wei, Paolo Bonzini
https://git.kernel.org/pub/scm/virt/kvm/kvm.git/commit/?id=f9336e3281880b683137bc18f91848ac34af84c3
> > ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5251 kvm_mmu_free_roots(vcpu, mmu, roots_to_free);
> > ce8fe7b77bd8ee Sean Christopherson 2020-03-20 5252
> > 55d2375e58a61b Sean Christopherson 2018-12-03 5253 return nested_vmx_succeed(vcpu);
> > 55d2375e58a61b Sean Christopherson 2018-12-03 5254 }
> > 55d2375e58a61b Sean Christopherson 2018-12-03 5255
> >
> > :::::: The code at line 5246 was first introduced by commit
> > :::::: 55d2375e58a61be072431dd3d3c8a320f4a4a01b KVM: nVMX: Move nested code to dedicated files
> >
> > :::::: TO: Sean Christopherson <sean.j.chr...@intel.com>
> > :::::: CC: Paolo Bonzini <pbon...@redhat.com>
> >
> > ---
> > 0-DAY CI Kernel Test Service, Intel Corporation
> > https://lists.01.org/hyperkitty/list/kbuil...@lists.01.org
> >
> > --
> > You received this message because you are subscribed to the Google Groups "Clang Built Linux" group.
> > To unsubscribe from this group and stop receiving emails from it, send an email to clang-built-li...@googlegroups.com.
> > To view this discussion on the web visit https://groups.google.com/d/msgid/clang-built-linux/202005162313.CDreQC6s%25lkp%40intel.com.
>
>
>
> --
> Thanks,
> ~Nick Desaulniers
>
Nathan
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