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(unknown [210.73.43.101]) by APP-05 (Coremail) with SMTP id zQCowAC3RgqO_o5pQN4uCA--.25463S3; Fri, 13 Feb 2026 18:36:00 +0800 (CST) From: Jiakai Xu To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, linux-kselftest@vger.kernel.org Cc: Anup Patel , Atish Patra , Paul Walmsley , Palmer Dabbelt , Albert Ou , Alexandre Ghiti , Andrew Jones , Paolo Bonzini , Shuah Khan , Jiakai Xu , Jiakai Xu , Andrew Jones Subject: [PATCH v7 1/3] RISC-V: KVM: Validate SBI STA shmem alignment in kvm_sbi_ext_sta_set_reg() Date: Fri, 13 Feb 2026 10:35:55 +0000 Message-Id: <20260213103557.3207335-2-xujiakai2025@iscas.ac.cn> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20260213103557.3207335-1-xujiakai2025@iscas.ac.cn> References: <20260213103557.3207335-1-xujiakai2025@iscas.ac.cn> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: zQCowAC3RgqO_o5pQN4uCA--.25463S3 X-Coremail-Antispam: 1UD129KBjvJXoWxXF4xXFyfKw4fZrW5Cry7trb_yoWrJF1UpF 42kw15ZrW8tFZ2k39rZw4vgr15u3ykKr1jqFy3W34xZF4kta4Yyrna93y7ZF98JryvvFWI yF10vF1DCw45AaDanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUHYb7Iv0xC_Kw4lb4IE77IF4wAFF20E14v26rWj6s0DM7CY07I2 0VC2zVCF04k26cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28IrcIa0xkI8VA2jI 8067AKxVWUGwA2048vs2IY020Ec7CjxVAFwI0_Gr0_Xr1l8cAvFVAK0II2c7xJM28CjxkF 64kEwVA0rcxSw2x7M28EF7xvwVC0I7IYx2IY67AKxVWUCVW8JwA2z4x0Y4vE2Ix0cI8IcV CY1x0267AKxVW8JVWxJwA2z4x0Y4vEx4A2jsIE14v26rxl6s0DM28EF7xvwVC2z280aVCY 1x0267AKxVW0oVCq3wAac4AC62xK8xCEY4vEwIxC4wAS0I0E0xvYzxvE52x082IY62kv04 87Mc02F40EFcxC0VAKzVAqx4xG6I80ewAv7VC0I7IYx2IY67AKxVWUJVWUGwAv7VC2z280 aVAFwI0_Jr0_Gr1lOx8S6xCaFVCjc4AY6r1j6r4UM4x0Y48IcxkI7VAKI48JM4x0x7Aq67 IIx4CEVc8vx2IErcIFxwACI402YVCY1x02628vn2kIc2xKxwCY1x0262kKe7AKxVW8ZVWr XwCF04k20xvY0x0EwIxGrwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E14v26r 1j6r18MI8I3I0E7480Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_GFv_WrylIxkGc2Ij 64vIr41lIxAIcVC0I7IYx2IY67AKxVWUJVWUCwCI42IY6xIIjxv20xvEc7CjxVAFwI0_Gr 0_Cr1lIxAIcVCF04k26cxKx2IYs7xG6r1j6r1xMIIF0xvEx4A2jsIE14v26r1j6r4UMIIF 0xvEx4A2jsIEc7CjxVAFwI0_Gr0_Gr1UYxBIdaVFxhVjvjDU0xZFpf9x07je-erUUUUU= X-CM-SenderInfo: 50xmxthndljiysv6x2xfdvhtffof0/1tbiCRARCWmOigf8bAAAs7 Content-Type: text/plain; charset="utf-8" The RISC-V SBI Steal-Time Accounting (STA) extension requires the shared memory physical address to be 64-byte aligned, or set to all-ones to explicitly disable steal-time accounting. KVM exposes the SBI STA shared memory configuration to userspace via KVM_SET_ONE_REG. However, the current implementation of kvm_sbi_ext_sta_set_reg() does not validate the alignment of the configured shared memory address. As a result, userspace can install a misaligned shared memory address that violates the SBI specification. Such an invalid configuration may later reach runtime code paths that assume a valid and properly aligned shared memory region. In particular, KVM_RUN can trigger the following WARN_ON in kvm_riscv_vcpu_record_steal_time(): WARNING: arch/riscv/kvm/vcpu_sbi_sta.c:49 at kvm_riscv_vcpu_record_steal_time WARN_ON paths are not expected to be reachable during normal runtime execution, and may result in a kernel panic when panic_on_warn is enabled. Fix this by validating the computed shared memory GPA at the KVM_SET_ONE_REG boundary. A temporary GPA is constructed and checked before committing it to vcpu->arch.sta.shmem. The validation allows either a 64-byte aligned GPA or INVALID_GPA (all-ones), which disables STA as defined by the SBI specification. This prevents invalid userspace state from reaching runtime code paths that assume SBI STA invariants and avoids unexpected WARN_ON behavior. Fixes: f61ce890b1f074 ("RISC-V: KVM: Add support for SBI STA registers") Signed-off-by: Jiakai Xu Signed-off-by: Jiakai Xu Reviewed-by: Andrew Jones --- V5 -> V6: Initialized new_shmem to INVALID_GPA as suggested. V4 -> V5: Added parentheses to function name in subject. V3 -> V4: Declared new_shmem at the top of kvm_sbi_ext_sta_set_reg(). Initialized new_shmem to 0 instead of vcpu->arch.sta.shmem. Added blank lines per review feedback. V2 -> V3: Added parentheses to function name in subject. V1 -> V2: Added Fixes tag. --- arch/riscv/kvm/vcpu_sbi_sta.c | 16 +++++++++++----- 1 file changed, 11 insertions(+), 5 deletions(-) diff --git a/arch/riscv/kvm/vcpu_sbi_sta.c b/arch/riscv/kvm/vcpu_sbi_sta.c index afa0545c3bcfc..3b834709b429f 100644 --- a/arch/riscv/kvm/vcpu_sbi_sta.c +++ b/arch/riscv/kvm/vcpu_sbi_sta.c @@ -181,6 +181,7 @@ static int kvm_sbi_ext_sta_set_reg(struct kvm_vcpu *vcp= u, unsigned long reg_num, unsigned long reg_size, const void *reg_val) { unsigned long value; + gpa_t new_shmem =3D INVALID_GPA; =20 if (reg_size !=3D sizeof(unsigned long)) return -EINVAL; @@ -191,18 +192,18 @@ static int kvm_sbi_ext_sta_set_reg(struct kvm_vcpu *v= cpu, unsigned long reg_num, if (IS_ENABLED(CONFIG_32BIT)) { gpa_t hi =3D upper_32_bits(vcpu->arch.sta.shmem); =20 - vcpu->arch.sta.shmem =3D value; - vcpu->arch.sta.shmem |=3D hi << 32; + new_shmem =3D value; + new_shmem |=3D hi << 32; } else { - vcpu->arch.sta.shmem =3D value; + new_shmem =3D value; } break; case KVM_REG_RISCV_SBI_STA_REG(shmem_hi): if (IS_ENABLED(CONFIG_32BIT)) { gpa_t lo =3D lower_32_bits(vcpu->arch.sta.shmem); =20 - vcpu->arch.sta.shmem =3D ((gpa_t)value << 32); - vcpu->arch.sta.shmem |=3D lo; + new_shmem =3D ((gpa_t)value << 32); + new_shmem |=3D lo; } else if (value !=3D 0) { return -EINVAL; } @@ -211,6 +212,11 @@ static int kvm_sbi_ext_sta_set_reg(struct kvm_vcpu *vc= pu, unsigned long reg_num, return -ENOENT; } =20 + if (new_shmem !=3D INVALID_GPA && !IS_ALIGNED(new_shmem, 64)) + return -EINVAL; + + vcpu->arch.sta.shmem =3D new_shmem; + return 0; } =20 --=20 2.34.1 From nobody Thu Apr 2 20:26:49 2026 Received: from cstnet.cn (smtp25.cstnet.cn [159.226.251.25]) (using TLSv1.2 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B463D335543; Fri, 13 Feb 2026 10:36:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=159.226.251.25 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770979021; cv=none; b=EVobwycMUoy6OzHTl9ih7yoArFEnxptpJrwGrUcRoMRJqgqjfsQWWsu2qCnWs0AlcE+ZgF0XS3NBbVBd15Hy+9GAEQGHRiGCy6IZBXhEWGbe9q7G//t3ylMoaA2oPWa/QZMJoMm/JG58dLtoQ5BXUuMmkZguYfSetPHhgFhyWzY= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770979021; c=relaxed/simple; bh=zwMKAQFVwkPKkCQMq65uZ1GxN38XckvtletF7h923/o=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=hPXqFmUou802tEtOcwEKH5QvIP7OUJx3owcZM0q/QLFDSmGJpWCgCUW0QZ9m0zR176eQFfaIZvNeANDYPzsoAYg9idHbm9rSx8RoVn6Zl+ID3nGY3b2edVgiQ1oyWxjzWj2FDPH7c8cnTuuRoyPfw+LKJ3FDzOQbIr4W1cNbAT8= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=iscas.ac.cn; spf=pass smtp.mailfrom=iscas.ac.cn; arc=none smtp.client-ip=159.226.251.25 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=iscas.ac.cn Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=iscas.ac.cn Received: from fric.. (unknown [210.73.43.101]) by APP-05 (Coremail) with SMTP id zQCowAC3RgqO_o5pQN4uCA--.25463S4; Fri, 13 Feb 2026 18:36:01 +0800 (CST) From: Jiakai Xu To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, linux-kselftest@vger.kernel.org Cc: Anup Patel , Atish Patra , Paul Walmsley , Palmer Dabbelt , Albert Ou , Alexandre Ghiti , Andrew Jones , Paolo Bonzini , Shuah Khan , Jiakai Xu , Jiakai Xu Subject: [PATCH v7 2/3] KVM: selftests: Refactor UAPI tests into dedicated function Date: Fri, 13 Feb 2026 10:35:56 +0000 Message-Id: <20260213103557.3207335-3-xujiakai2025@iscas.ac.cn> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20260213103557.3207335-1-xujiakai2025@iscas.ac.cn> References: <20260213103557.3207335-1-xujiakai2025@iscas.ac.cn> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: zQCowAC3RgqO_o5pQN4uCA--.25463S4 X-Coremail-Antispam: 1UD129KBjvJXoWxtr4kXr17Gr18Jr17urWUtwb_yoW7XFWkpF 97CrZIqrW8tr4fKw1xWrWv9F15Gw4vkrn7Zry7Zw4rAr4kKrZrJF1xCryjvF98KFZ5X3Wf Za4SvF47uF4qkF7anT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUQY14x267AKxVWrJVCq3wAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2048vs2IY020E87I2jVAFwI0_Jryl82xGYIkIc2 x26xkF7I0E14v26ryj6s0DM28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48ve4kI8wA2z4x0 Y4vE2Ix0cI8IcVAFwI0_Gr0_Xr1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI0_Cr0_Gr1UM2 8EF7xvwVC2z280aVAFwI0_GcCE3s1l84ACjcxK6I8E87Iv6xkF7I0E14v26rxl6s0DM2vY z4IE04k24VAvwVAKI4IrM2AIxVAIcxkEcVAq07x20xvEncxIr21l5I8CrVACY4xI64kE6c 02F40Ex7xfMcIj6xIIjxv20xvE14v26r1j6r18McIj6I8E87Iv67AKxVWUJVW8JwAm72CE 4IkC6x0Yz7v_Jr0_Gr1lF7xvr2IYc2Ij64vIr41lF7I21c0EjII2zVCS5cI20VAGYxC7M4 IIrI8v6xkF7I0E8cxan2IY04v7MxkF7I0En4kS14v26r1q6r43MxAIw28IcxkI7VAKI48J MxC20s026xCaFVCjc4AY6r1j6r4UMI8I3I0E5I8CrVAFwI0_Jr0_Jr4lx2IqxVCjr7xvwV AFwI0_JrI_JrWlx4CE17CEb7AF67AKxVW8ZVWrXwCIc40Y0x0EwIxGrwCI42IY6xIIjxv2 0xvE14v26r1j6r1xMIIF0xvE2Ix0cI8IcVCY1x0267AKxVW8JVWxJwCI42IY6xAIw20EY4 v20xvaj40_Jr0_JF4lIxAIcVC2z280aVAFwI0_Jr0_Gr1lIxAIcVC2z280aVCY1x0267AK xVW8JVW8JrUvcSsGvfC2KfnxnUUI43ZEXa7VUbyCJJUUUUU== X-CM-SenderInfo: 50xmxthndljiysv6x2xfdvhtffof0/1tbiBwoRCWmOijX6igAAs9 Content-Type: text/plain; charset="utf-8" Move steal time UAPI tests from steal_time_init() into a separate check_steal_time_uapi() function for better code organization and maintainability. Previously, x86 and ARM64 architectures performed UAPI validation tests within steal_time_init(), mixing initialization logic with uapi tests. Changes by architecture: x86_64: - Extract MSR reserved bits test from steal_time_init() - Move to check_steal_time_uapi() which tests that setting MSR_KVM_STEAL_TIME with KVM_STEAL_RESERVED_MASK fails ARM64: - Extract three UAPI tests from steal_time_init(): Device attribute support check Misaligned IPA rejection (EINVAL) Duplicate IPA setting rejection (EEXIST) - Move all tests to check_steal_time_uapi() RISC-V: - Add empty check_steal_time_uapi() stub for future use - No changes to steal_time_init() (had no tests to extract) The new check_steal_time_uapi() function: - Is called once before the per-VCPU test loop No functional change intended. Signed-off-by: Jiakai Xu Signed-off-by: Jiakai Xu Suggested-by: Andrew Jones --- tools/testing/selftests/kvm/steal_time.c | 63 ++++++++++++++++++------ 1 file changed, 47 insertions(+), 16 deletions(-) diff --git a/tools/testing/selftests/kvm/steal_time.c b/tools/testing/selft= ests/kvm/steal_time.c index 8edc1fca345ba..a814f6f3f8b41 100644 --- a/tools/testing/selftests/kvm/steal_time.c +++ b/tools/testing/selftests/kvm/steal_time.c @@ -69,16 +69,10 @@ static bool is_steal_time_supported(struct kvm_vcpu *vc= pu) =20 static void steal_time_init(struct kvm_vcpu *vcpu, uint32_t i) { - int ret; - /* ST_GPA_BASE is identity mapped */ st_gva[i] =3D (void *)(ST_GPA_BASE + i * STEAL_TIME_SIZE); sync_global_to_guest(vcpu->vm, st_gva[i]); =20 - ret =3D _vcpu_set_msr(vcpu, MSR_KVM_STEAL_TIME, - (ulong)st_gva[i] | KVM_STEAL_RESERVED_MASK); - TEST_ASSERT(ret =3D=3D 0, "Bad GPA didn't fail"); - vcpu_set_msr(vcpu, MSR_KVM_STEAL_TIME, (ulong)st_gva[i] | KVM_MSR_ENABLED= ); } =20 @@ -99,6 +93,18 @@ static void steal_time_dump(struct kvm_vm *vm, uint32_t = vcpu_idx) st->pad[8], st->pad[9], st->pad[10]); } =20 +static void check_steal_time_uapi(struct kvm_vcpu *vcpu) +{ + int ret; + + st_gva[0] =3D (void *)(ST_GPA_BASE); + sync_global_to_guest(vcpu->vm, st_gva[0]); + + ret =3D _vcpu_set_msr(vcpu, MSR_KVM_STEAL_TIME, + (ulong)st_gva[0] | KVM_STEAL_RESERVED_MASK); + TEST_ASSERT(ret =3D=3D 0, "Bad GPA didn't fail"); +} + #elif defined(__aarch64__) =20 /* PV_TIME_ST must have 64-byte alignment */ @@ -170,7 +176,6 @@ static void steal_time_init(struct kvm_vcpu *vcpu, uint= 32_t i) { struct kvm_vm *vm =3D vcpu->vm; uint64_t st_ipa; - int ret; =20 struct kvm_device_attr dev =3D { .group =3D KVM_ARM_VCPU_PVTIME_CTRL, @@ -178,21 +183,12 @@ static void steal_time_init(struct kvm_vcpu *vcpu, ui= nt32_t i) .addr =3D (uint64_t)&st_ipa, }; =20 - vcpu_ioctl(vcpu, KVM_HAS_DEVICE_ATTR, &dev); - /* ST_GPA_BASE is identity mapped */ st_gva[i] =3D (void *)(ST_GPA_BASE + i * STEAL_TIME_SIZE); sync_global_to_guest(vm, st_gva[i]); =20 - st_ipa =3D (ulong)st_gva[i] | 1; - ret =3D __vcpu_ioctl(vcpu, KVM_SET_DEVICE_ATTR, &dev); - TEST_ASSERT(ret =3D=3D -1 && errno =3D=3D EINVAL, "Bad IPA didn't report = EINVAL"); - st_ipa =3D (ulong)st_gva[i]; vcpu_ioctl(vcpu, KVM_SET_DEVICE_ATTR, &dev); - - ret =3D __vcpu_ioctl(vcpu, KVM_SET_DEVICE_ATTR, &dev); - TEST_ASSERT(ret =3D=3D -1 && errno =3D=3D EEXIST, "Set IPA twice without = EEXIST"); } =20 static void steal_time_dump(struct kvm_vm *vm, uint32_t vcpu_idx) @@ -205,6 +201,34 @@ static void steal_time_dump(struct kvm_vm *vm, uint32_= t vcpu_idx) ksft_print_msg(" st_time: %ld\n", st->st_time); } =20 +static void check_steal_time_uapi(struct kvm_vcpu *vcpu) +{ + struct kvm_vm *vm =3D vcpu->vm; + uint64_t st_ipa; + int ret; + + struct kvm_device_attr dev =3D { + .group =3D KVM_ARM_VCPU_PVTIME_CTRL, + .attr =3D KVM_ARM_VCPU_PVTIME_IPA, + .addr =3D (uint64_t)&st_ipa, + }; + + vcpu_ioctl(vcpu, KVM_HAS_DEVICE_ATTR, &dev); + + st_gva[0] =3D (void *)(ST_GPA_BASE); + sync_global_to_guest(vm, st_gva[0]); + + st_ipa =3D (ulong)st_gva[0] | 1; + ret =3D __vcpu_ioctl(vcpu, KVM_SET_DEVICE_ATTR, &dev); + TEST_ASSERT(ret =3D=3D -1 && errno =3D=3D EINVAL, "Bad IPA didn't report = EINVAL"); + + st_ipa =3D (ulong)st_gva[0]; + vcpu_ioctl(vcpu, KVM_SET_DEVICE_ATTR, &dev); + + ret =3D __vcpu_ioctl(vcpu, KVM_SET_DEVICE_ATTR, &dev); + TEST_ASSERT(ret =3D=3D -1 && errno =3D=3D EEXIST, "Set IPA twice without = EEXIST"); +} + #elif defined(__riscv) =20 /* SBI STA shmem must have 64-byte alignment */ @@ -301,6 +325,11 @@ static void steal_time_dump(struct kvm_vm *vm, uint32_= t vcpu_idx) pr_info("\n"); } =20 +static void check_steal_time_uapi(struct kvm_vcpu *vcpu) +{ + /* RISC-V UAPI tests will be added in a subsequent patch */ +} + #endif =20 static void *do_steal_time(void *arg) @@ -369,6 +398,8 @@ int main(int ac, char **av) TEST_REQUIRE(is_steal_time_supported(vcpus[0])); ksft_set_plan(NR_VCPUS); =20 + check_steal_time_uapi(vcpus[0]); + /* Run test on each VCPU */ for (i =3D 0; i < NR_VCPUS; ++i) { steal_time_init(vcpus[i], i); --=20 2.34.1 From nobody Thu Apr 2 20:26:49 2026 Received: from cstnet.cn (smtp25.cstnet.cn [159.226.251.25]) (using TLSv1.2 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B45B432ED45; 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(unknown [210.73.43.101]) by APP-05 (Coremail) with SMTP id zQCowAC3RgqO_o5pQN4uCA--.25463S5; Fri, 13 Feb 2026 18:36:02 +0800 (CST) From: Jiakai Xu To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, linux-kselftest@vger.kernel.org Cc: Anup Patel , Atish Patra , Paul Walmsley , Palmer Dabbelt , Albert Ou , Alexandre Ghiti , Andrew Jones , Paolo Bonzini , Shuah Khan , Jiakai Xu , Jiakai Xu Subject: [PATCH v7 3/3] RISC-V: KVM: selftests: Add RISC-V SBI STA shmem alignment tests Date: Fri, 13 Feb 2026 10:35:57 +0000 Message-Id: <20260213103557.3207335-4-xujiakai2025@iscas.ac.cn> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20260213103557.3207335-1-xujiakai2025@iscas.ac.cn> References: <20260213103557.3207335-1-xujiakai2025@iscas.ac.cn> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: zQCowAC3RgqO_o5pQN4uCA--.25463S5 X-Coremail-Antispam: 1UD129KBjvJXoWxCr1fKw17CrWDCF4rurWrGrg_yoW5Xr4fpr Z7Gr90qrW8trs3t34xKr1vqF4FgrWvkr4vvry7Zw4rAF4xtF1xJryUKFyDZ343WrZ5XF1S vFySqF45uF4DAaDanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUQF14x267AKxVWrJVCq3wAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2048vs2IY020E87I2jVAFwI0_JrWl82xGYIkIc2 x26xkF7I0E14v26ryj6s0DM28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48ve4kI8wA2z4x0 Y4vE2Ix0cI8IcVAFwI0_Gr0_Xr1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI0_Cr0_Gr1UM2 8EF7xvwVC2z280aVAFwI0_GcCE3s1l84ACjcxK6I8E87Iv6xkF7I0E14v26rxl6s0DM2vY z4IE04k24VAvwVAKI4IrM2AIxVAIcxkEcVAq07x20xvEncxIr21l5I8CrVACY4xI64kE6c 02F40Ex7xfMcIj6xIIjxv20xvE14v26r1j6r18McIj6I8E87Iv67AKxVWUJVW8JwAm72CE 4IkC6x0Yz7v_Jr0_Gr1lF7xvr2IYc2Ij64vIr41lF7I21c0EjII2zVCS5cI20VAGYxC7M4 IIrI8v6xkF7I0E8cxan2IY04v7MxkF7I0En4kS14v26r1q6r43MxAIw28IcxkI7VAKI48J MxC20s026xCaFVCjc4AY6r1j6r4UMI8I3I0E5I8CrVAFwI0_Jr0_Jr4lx2IqxVCjr7xvwV AFwI0_JrI_JrWlx4CE17CEb7AF67AKxVW8ZVWrXwCIc40Y0x0EwIxGrwCI42IY6xIIjxv2 0xvE14v26r1j6r1xMIIF0xvE2Ix0cI8IcVCY1x0267AKxVWxJVW8Jr1lIxAIcVCF04k26c xKx2IYs7xG6r1j6r1xMIIF0xvEx4A2jsIE14v26r1j6r4UMIIF0xvEx4A2jsIEc7CjxVAF wI0_Gr0_Gr1UYxBIdaVFxhVjvjDU0xZFpf9x0JUmiifUUUUU= X-CM-SenderInfo: 50xmxthndljiysv6x2xfdvhtffof0/1tbiCRARCWmOigf8bQACs4 Content-Type: text/plain; charset="utf-8" Add RISC-V KVM selftests to verify the SBI Steal-Time Accounting (STA) shared memory alignment requirements. The SBI specification requires the STA shared memory GPA to be 64-byte aligned, or set to all-ones to explicitly disable steal-time accounting. This test verifies that KVM enforces the expected behavior when configuring the SBI STA shared memory via KVM_SET_ONE_REG. Specifically, the test checks that: - misaligned GPAs are rejected with -EINVAL - 64-byte aligned GPAs are accepted - all-ones GPA is accepted Signed-off-by: Jiakai Xu Signed-off-by: Jiakai Xu --- V6 -> V7:=20 - Removed RISCV_SBI_STA_REG() macro addition and used existing=20 KVM_REG_RISCV_SBI_STA_REG(shmem_lo) instead. - Refined assertion messages per review feedback. - Split into two patches per Andrew Jones' suggestion: Refactored UAPI tests from steal_time_init() into dedicated=20 check_steal_time_uapi() function and added empty stub for=20 RISC-V. Filled in RISC-V stub with STA alignment tests. (this patch) --- tools/testing/selftests/kvm/steal_time.c | 26 +++++++++++++++++++++++- 1 file changed, 25 insertions(+), 1 deletion(-) diff --git a/tools/testing/selftests/kvm/steal_time.c b/tools/testing/selft= ests/kvm/steal_time.c index a814f6f3f8b41..2af7fd7513d55 100644 --- a/tools/testing/selftests/kvm/steal_time.c +++ b/tools/testing/selftests/kvm/steal_time.c @@ -233,6 +233,7 @@ static void check_steal_time_uapi(struct kvm_vcpu *vcpu) =20 /* SBI STA shmem must have 64-byte alignment */ #define STEAL_TIME_SIZE ((sizeof(struct sta_struct) + 63) & ~63) +#define INVALID_GPA (~(u64)0) =20 static vm_paddr_t st_gpa[NR_VCPUS]; =20 @@ -327,7 +328,30 @@ static void steal_time_dump(struct kvm_vm *vm, uint32_= t vcpu_idx) =20 static void check_steal_time_uapi(struct kvm_vcpu *vcpu) { - /* RISC-V UAPI tests will be added in a subsequent patch */ + struct kvm_one_reg reg; + uint64_t shmem; + int ret; + + reg.id =3D KVM_REG_RISCV_SBI_STA_REG(shmem_lo); + reg.addr =3D (uint64_t)&shmem; + + /* Case 1: misaligned GPA */ + shmem =3D ST_GPA_BASE + 1; + ret =3D __vcpu_ioctl(vcpu, KVM_SET_ONE_REG, ®); + TEST_ASSERT(ret =3D=3D -1 && errno =3D=3D EINVAL, + "misaligned STA shmem returns -EINVAL"); + + /* Case 2: 64-byte aligned GPA */ + shmem =3D ST_GPA_BASE; + ret =3D __vcpu_ioctl(vcpu, KVM_SET_ONE_REG, ®); + TEST_ASSERT(ret =3D=3D 0, + "aligned STA shmem succeeds"); + + /* Case 3: INVALID_GPA disables STA */ + shmem =3D INVALID_GPA; + ret =3D __vcpu_ioctl(vcpu, KVM_SET_ONE_REG, ®); + TEST_ASSERT(ret =3D=3D 0, + "all-ones for STA shmem succeeds"); } =20 #endif --=20 2.34.1