diff options
authorJames Cowgill <>2017-06-20 10:57:51 +0100
committerRadim Krčmář <>2017-06-20 17:02:48 +0200
commite27a9eca5d4a392b96ce5d5238c8d637bcb0a52c (patch)
parentc72544d85fd6e46cfca6056ba775a17dc272d810 (diff)
KVM: MIPS: Fix maybe-uninitialized build failure
This commit fixes a "maybe-uninitialized" build failure in arch/mips/kvm/tlb.c when KVM, DYNAMIC_DEBUG and JUMP_LABEL are all enabled. The failure is: In file included from ./include/linux/printk.h:329:0, from ./include/linux/kernel.h:13, from ./include/asm-generic/bug.h:15, from ./arch/mips/include/asm/bug.h:41, from ./include/linux/bug.h:4, from ./include/linux/thread_info.h:11, from ./include/asm-generic/current.h:4, from ./arch/mips/include/generated/asm/current.h:1, from ./include/linux/sched.h:11, from arch/mips/kvm/tlb.c:13: arch/mips/kvm/tlb.c: In function ‘kvm_mips_host_tlb_inv’: ./include/linux/dynamic_debug.h:126:3: error: ‘idx_kernel’ may be used uninitialized in this function [-Werror=maybe-uninitialized] __dynamic_pr_debug(&descriptor, pr_fmt(fmt), \ ^~~~~~~~~~~~~~~~~~ arch/mips/kvm/tlb.c:169:16: note: ‘idx_kernel’ was declared here int idx_user, idx_kernel; ^~~~~~~~~~ There is a similar error relating to "idx_user". Both errors were observed with GCC 6. As far as I can tell, it is impossible for either idx_user or idx_kernel to be uninitialized when they are later read in the calls to kvm_debug, but to satisfy the compiler, add zero initializers to both variables. Signed-off-by: James Cowgill <> Fixes: 57e3869cfaae ("KVM: MIPS/TLB: Generalise host TLB invalidate to kernel ASID") Cc: <> # 4.11+ Acked-by: James Hogan <> Signed-off-by: Radim Krčmář <>
1 files changed, 5 insertions, 1 deletions
diff --git a/arch/mips/kvm/tlb.c b/arch/mips/kvm/tlb.c
index 7c6336dd2638..7cd92166a0b9 100644
--- a/arch/mips/kvm/tlb.c
+++ b/arch/mips/kvm/tlb.c
@@ -166,7 +166,11 @@ static int _kvm_mips_host_tlb_inv(unsigned long entryhi)
int kvm_mips_host_tlb_inv(struct kvm_vcpu *vcpu, unsigned long va,
bool user, bool kernel)
- int idx_user, idx_kernel;
+ /*
+ * Initialize idx_user and idx_kernel to workaround bogus
+ * maybe-initialized warning when using GCC 6.
+ */
+ int idx_user = 0, idx_kernel = 0;
unsigned long flags, old_entryhi;