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envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=2607:f8b0:4864:20::32e; envelope-from=danielhb413@gmail.com; helo=mail-ot1-x32e.google.com X-Spam_score_int: -3 X-Spam_score: -0.4 X-Spam_bar: / X-Spam_report: (-0.4 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, FREEMAIL_ENVFROM_END_DIGIT=0.25, FREEMAIL_FROM=0.001, PDS_HP_HELO_NORDNS=0.659, RCVD_IN_DNSWL_NONE=-0.0001, RDNS_NONE=0.793, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=no autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Daniel Henrique Barboza , qemu-ppc@nongnu.org, clg@kaod.org, david@gibson.dropbear.id.au Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) X-ZM-MESSAGEID: 1648674399390100001 Content-Type: text/plain; charset="utf-8" Valgrind isn't convinced that we are initializing the values we assign to env->spr[spr] because it doesn't understand that the 'reg_val' union is being written by the kvm_vcpu_ioctl() that follows (via struct kvm_one_reg). This results in Valgrind complaining about uninitialized values every time we use env->spr in a conditional, like this instance: =3D=3D707578=3D=3D Thread 1: =3D=3D707578=3D=3D Conditional jump or move depends on uninitialised value(= s) =3D=3D707578=3D=3D at 0xA10A40: hreg_compute_hflags_value (helper_regs.c= :106) =3D=3D707578=3D=3D by 0xA10C9F: hreg_compute_hflags (helper_regs.c:173) =3D=3D707578=3D=3D by 0xA110F7: hreg_store_msr (helper_regs.c:262) =3D=3D707578=3D=3D by 0xA051A3: ppc_cpu_reset (cpu_init.c:7168) =3D=3D707578=3D=3D by 0xD4730F: device_transitional_reset (qdev.c:799) =3D=3D707578=3D=3D by 0xD4A11B: resettable_phase_hold (resettable.c:182) =3D=3D707578=3D=3D by 0xD49A77: resettable_assert_reset (resettable.c:60) =3D=3D707578=3D=3D by 0xD4994B: resettable_reset (resettable.c:45) =3D=3D707578=3D=3D by 0xD458BB: device_cold_reset (qdev.c:296) =3D=3D707578=3D=3D by 0x48FBC7: cpu_reset (cpu-common.c:114) =3D=3D707578=3D=3D by 0x97B5EB: spapr_reset_vcpu (spapr_cpu_core.c:38) =3D=3D707578=3D=3D by 0x97BABB: spapr_cpu_core_reset (spapr_cpu_core.c:2= 09) =3D=3D707578=3D=3D Uninitialised value was created by a stack allocation =3D=3D707578=3D=3D at 0xB11F08: kvm_get_one_spr (kvm.c:543) Initializing 'reg_val' has no impact in the logic and makes Valgrind output more bearable. Signed-off-by: Daniel Henrique Barboza --- target/ppc/kvm.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/target/ppc/kvm.c b/target/ppc/kvm.c index dc93b99189..ce1b926e8c 100644 --- a/target/ppc/kvm.c +++ b/target/ppc/kvm.c @@ -543,10 +543,12 @@ static void kvm_get_one_spr(CPUState *cs, uint64_t id= , int spr) { PowerPCCPU *cpu =3D POWERPC_CPU(cs); CPUPPCState *env =3D &cpu->env; - union { + union reg_val { uint32_t u32; uint64_t u64; - } val; + }; + /* Init reg_val to avoid "uninitialised value" Valgrind warnings */ + union reg_val val =3D {0}; struct kvm_one_reg reg =3D { .id =3D id, .addr =3D (uintptr_t) &val, --=20 2.35.1