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(unknown [210.73.43.101]) by APP-01 (Coremail) with SMTP id qwCowAB3HWkjBaBpUDDFCA--.13513S3; Thu, 26 Feb 2026 16:32:37 +0800 (CST) From: Jiakai Xu To: linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, kvm-riscv@lists.infradead.org, linux-kselftest@vger.kernel.org, kvm@vger.kernel.org Cc: Alexandre Ghiti , Paolo Bonzini , Shuah Khan , Paul Walmsley , Palmer Dabbelt , Andrew Jones , Anup Patel , Atish Patra , Albert Ou , Jiakai Xu , Jiakai Xu , Andrew Jones Subject: [PATCH v8 1/3] RISC-V: KVM: Validate SBI STA shmem alignment in kvm_sbi_ext_sta_set_reg() Date: Thu, 26 Feb 2026 08:32:32 +0000 Message-Id: <20260226083234.634716-2-xujiakai2025@iscas.ac.cn> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20260226083234.634716-1-xujiakai2025@iscas.ac.cn> References: <20260226083234.634716-1-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: qwCowAB3HWkjBaBpUDDFCA--.13513S3 X-Coremail-Antispam: 1UD129KBjvJXoWxXF4xXFyfKw4fZrW5Cry7trb_yoWrJF1UpF 42kw15ZrW8tFZ2k39rZw4vgr15u3ykKr1jqFy3W34xZF4kta4Yyrna93y7ZF98JryvvFWI yF10vF1DCw45AaDanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUHFb7Iv0xC_Kw4lb4IE77IF4wAFF20E14v26rWj6s0DM7CY07I2 0VC2zVCF04k26cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28IrcIa0xkI8VA2jI 8067AKxVWUGwA2048vs2IY020Ec7CjxVAFwI0_Gr0_Xr1l8cAvFVAK0II2c7xJM28CjxkF 64kEwVA0rcxSw2x7M28EF7xvwVC0I7IYx2IY67AKxVW7JVWDJwA2z4x0Y4vE2Ix0cI8IcV CY1x0267AKxVWxJVW8Jr1l84ACjcxK6I8E87Iv67AKxVW0oVCq3wA2z4x0Y4vEx4A2jsIE c7CjxVAFwI0_GcCE3s1lnxkEFVAIw20F6cxK64vIFxWle2I262IYc4CY6c8Ij28IcVAaY2 xG8wAqx4xG64xvF2IEw4CE5I8CrVC2j2WlYx0E2Ix0cI8IcVAFwI0_Jr0_Jr4lYx0Ex4A2 jsIE14v26r4j6F4UMcvjeVCFs4IE7xkEbVWUJVW8JwACjcxG0xvY0x0EwIxGrwACjI8F5V A0II8E6IAqYI8I648v4I1lFIxGxcIEc7CjxVA2Y2ka0xkIwI1lc7CjxVAaw2AFwI0_GFv_ Wryl42xK82IYc2Ij64vIr41l4I8I3I0E4IkC6x0Yz7v_Jr0_Gr1lx2IqxVAqx4xG67AKxV WUJVWUGwC20s026x8GjcxK67AKxVWUGVWUWwC2zVAF1VAY17CE14v26r4a6rW5MIIYrxkI 7VAKI48JMIIF0xvE2Ix0cI8IcVAFwI0_Jr0_JF4lIxAIcVC0I7IYx2IY6xkF7I0E14v26r 4j6F4UMIIF0xvE42xK8VAvwI8IcIk0rVWUJVWUCwCI42IY6I8E87Iv67AKxVWUJVW8JwCI 42IY6I8E87Iv6xkF7I0E14v26r4j6r4UJbIYCTnIWIevJa73UjIFyTuYvjxU47KsUUUUU X-CM-SenderInfo: 50xmxthndljiysv6x2xfdvhtffof0/1tbiBwkJCWmeY4AargAEsq 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 16 19:19:01 2026 Received: from cstnet.cn (smtp21.cstnet.cn [159.226.251.21]) (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 B33152C0F6F; Thu, 26 Feb 2026 08:33:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=159.226.251.21 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772094789; cv=none; b=TNR8FWkWrOygbYgDKBZmFbePJFkb1xKoWuu+ykI7QOIKaTs4qYoqfn3BfM7//1agG8MKz7zFYOyP/iRffGPzkCp9Zjr8wAW18/UFqx0mwRNQdRdjWjDZBaKQFQrcWdTvNGGK9hP+9As3XhVArMB+GUgLCgQL4jvEbEzHmZEJ5Io= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772094789; c=relaxed/simple; bh=rHO6/pOQ78+7RUX6EmYeqVaafWwenambqT3Mo6TQyfA=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=ndaTQ3fUwgGFz1LYWLGwkXqhrILJkiexOU5U5lRzmqgIQrp7tnHqiSIMw4aGuI87ZWa7ByWcS+gcXViWl8HWfg/gId25SheLeAbzZcaR8iLsi5nsd426QQ6BAqlGgqXE1nskA7WSycynZTuVo5+zx4Vr5CPaAdVYX/260nzn8TU= 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=159.226.251.21 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-01 (Coremail) with SMTP id qwCowAB3HWkjBaBpUDDFCA--.13513S4; Thu, 26 Feb 2026 16:32:38 +0800 (CST) From: Jiakai Xu To: linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, kvm-riscv@lists.infradead.org, linux-kselftest@vger.kernel.org, kvm@vger.kernel.org Cc: Alexandre Ghiti , Paolo Bonzini , Shuah Khan , Paul Walmsley , Palmer Dabbelt , Andrew Jones , Anup Patel , Atish Patra , Albert Ou , Jiakai Xu , Andrew Jones , Jiakai Xu Subject: [PATCH v8 2/3] KVM: selftests: Refactor UAPI tests into dedicated function Date: Thu, 26 Feb 2026 08:32:33 +0000 Message-Id: <20260226083234.634716-3-xujiakai2025@iscas.ac.cn> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20260226083234.634716-1-xujiakai2025@iscas.ac.cn> References: <20260226083234.634716-1-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: qwCowAB3HWkjBaBpUDDFCA--.13513S4 X-Coremail-Antispam: 1UD129KBjvJXoWxtr4kXr17Jw43Kw13ZFWfuFg_yoW7CryDpF Z7CrsIqrW8trWfKw17Gr4kuF15Gw4kKr4kury3Zw4rAr4kKrZrJF1IgFyUZF98GFWkX3Wf Za4rZF47uF4qkaUanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUQF14x267AKxVWrJVCq3wAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2048vs2IY020E87I2jVAFwI0_Jryl82xGYIkIc2 x26xkF7I0E14v26ryj6s0DM28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48ve4kI8wA2z4x0 Y4vE2Ix0cI8IcVAFwI0_Ar0_tr1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI0_Gr1j6F4UJw A2z4x0Y4vEx4A2jsIE14v26rxl6s0DM28EF7xvwVC2z280aVCY1x0267AKxVW0oVCq3wAa c4AC62xK8xCEY4vEwIxC4wAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC0VAKzV Aqx4xG6I80ewAv7VC0I7IYx2IY67AKxVWUJVWUGwAv7VC2z280aVAFwI0_Gr0_Cr1lOx8S 6xCaFVCjc4AY6r1j6r4UM4x0Y48IcxkI7VAKI48JM4x0x7Aq67IIx4CEVc8vx2IErcIFxw ACI402YVCY1x02628vn2kIc2xKxwCY1x0262kKe7AKxVW8ZVWrXwCF04k20xvY0x0EwIxG rwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E14v26r1j6r18MI8I3I0E7480Y4 vE14v26r106r1rMI8E67AF67kF1VAFwI0_GFv_WrylIxkGc2Ij64vIr41lIxAIcVC0I7IY x2IY67AKxVWUJVWUCwCI42IY6xIIjxv20xvEc7CjxVAFwI0_Gr0_Cr1lIxAIcVCF04k26c xKx2IYs7xG6r1j6r1xMIIF0xvEx4A2jsIE14v26r1j6r4UMIIF0xvEx4A2jsIEc7CjxVAF wI0_Gr0_Gr1UYxBIdaVFxhVjvjDU0xZFpf9x0pR2Q6LUUUUU= X-CM-SenderInfo: 50xmxthndljiysv6x2xfdvhtffof0/1tbiCQ4KCWmf1uCqDwABsg 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. Suggested-by: Andrew Jones Signed-off-by: Jiakai Xu Signed-off-by: Jiakai Xu --- V7 -> V8: Used ST_GPA_BASE directly instead of st_gva[]/sync_global_to_guest() in x86_64 and ARM64 check_steal_time_uapi(). Created a temporary vcpu in ARM64 check_steal_time_uapi() to avoid EEXIST when steal_time_init() later sets IPA for vcpu[0]. Removed unnecessary comment in RISC-V check_steal_time_uapi(). --- tools/testing/selftests/kvm/steal_time.c | 59 +++++++++++++++++------- 1 file changed, 43 insertions(+), 16 deletions(-) diff --git a/tools/testing/selftests/kvm/steal_time.c b/tools/testing/selft= ests/kvm/steal_time.c index 8edc1fca345ba..6f77df4deaad3 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 +93,15 @@ 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; + + ret =3D _vcpu_set_msr(vcpu, MSR_KVM_STEAL_TIME, + (ulong)ST_GPA_BASE | 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 +173,6 @@ 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 +180,12 @@ 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 +198,34 @@ 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; + struct kvm_vcpu *tmp_vcpu =3D vm_vcpu_add(vm, NR_VCPUS, guest_code); + 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(tmp_vcpu, KVM_HAS_DEVICE_ATTR, &dev); + + st_ipa =3D (ulong)ST_GPA_BASE | 1; + ret =3D __vcpu_ioctl(tmp_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_GPA_BASE; + vcpu_ioctl(tmp_vcpu, KVM_SET_DEVICE_ATTR, &dev); + + ret =3D __vcpu_ioctl(tmp_vcpu, KVM_SET_DEVICE_ATTR, &dev); + TEST_ASSERT(ret =3D=3D -1 && errno =3D=3D EEXIST, "Set IPA twice without = EEXIST"); + + vm_vcpu_rm(vm, tmp_vcpu); +} + #elif defined(__riscv) =20 /* SBI STA shmem must have 64-byte alignment */ @@ -301,6 +322,10 @@ 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) +{ +} + #endif =20 static void *do_steal_time(void *arg) @@ -369,6 +394,8 @@ 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 16 19:19:01 2026 Received: from cstnet.cn (smtp21.cstnet.cn [159.226.251.21]) (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 B33A82EFDA1; 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(unknown [210.73.43.101]) by APP-01 (Coremail) with SMTP id qwCowAB3HWkjBaBpUDDFCA--.13513S5; Thu, 26 Feb 2026 16:32:39 +0800 (CST) From: Jiakai Xu To: linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, kvm-riscv@lists.infradead.org, linux-kselftest@vger.kernel.org, kvm@vger.kernel.org Cc: Alexandre Ghiti , Paolo Bonzini , Shuah Khan , Paul Walmsley , Palmer Dabbelt , Andrew Jones , Anup Patel , Atish Patra , Albert Ou , Jiakai Xu , Jiakai Xu Subject: [PATCH v8 3/3] RISC-V: KVM: selftests: Add RISC-V SBI STA shmem alignment tests Date: Thu, 26 Feb 2026 08:32:34 +0000 Message-Id: <20260226083234.634716-4-xujiakai2025@iscas.ac.cn> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20260226083234.634716-1-xujiakai2025@iscas.ac.cn> References: <20260226083234.634716-1-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: qwCowAB3HWkjBaBpUDDFCA--.13513S5 X-Coremail-Antispam: 1UD129KBjvJXoWxCr1fKw17Cryfur4fuFWfKrg_yoW5Zr4rpF ykCFnYgr18Kw4fA3yxKr4kXFWfWw4vyr4vv3y3Zw40yF4xAF4xAry7KF4DZas8ursYqF1S vFyIgF4UuF4DAaDanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUQ214x267AKxVWrJVCq3wAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2048vs2IY020E87I2jVAFwI0_JrWl82xGYIkIc2 x26xkF7I0E14v26ryj6s0DM28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48ve4kI8wA2z4x0 Y4vE2Ix0cI8IcVAFwI0_Ar0_tr1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI0_Gr1j6F4UJw A2z4x0Y4vEx4A2jsIE14v26rxl6s0DM28EF7xvwVC2z280aVCY1x0267AKxVW0oVCq3wAa c4AC62xK8xCEY4vEwIxC4wAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC0VAKzV Aqx4xG6I80ewAv7VC0I7IYx2IY67AKxVWUJVWUGwAv7VC2z280aVAFwI0_Gr0_Cr1lOx8S 6xCaFVCjc4AY6r1j6r4UM4x0Y48IcxkI7VAKI48JM4x0x7Aq67IIx4CEVc8vx2IErcIFxw ACI402YVCY1x02628vn2kIc2xKxwCY1x0262kKe7AKxVWUtVW8ZwCF04k20xvY0x0EwIxG rwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E14v26r1j6r18MI8I3I0E7480Y4 vE14v26r106r1rMI8E67AF67kF1VAFwI0_GFv_WrylIxkGc2Ij64vIr41lIxAIcVC0I7IY x2IY67AKxVWUJVWUCwCI42IY6xIIjxv20xvEc7CjxVAFwI0_Cr0_Gr1UMIIF0xvE42xK8V AvwI8IcIk0rVWUJVWUCwCI42IY6I8E87Iv67AKxVWUJVW8JwCI42IY6I8E87Iv6xkF7I0E 14v26r4j6r4UJbIYCTnIWIevJa73UjIFyTuYvjfUeHUDUUUUU X-CM-SenderInfo: 50xmxthndljiysv6x2xfdvhtffof0/1tbiBwsKCWmf1qeqwAAAsi 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 --- V7 -> V8: Moved INVALID_GPA definition to kvm_util_types.h. Removed comments in RISC-V check_steal_time_uapi(). Corrected reg.id assignment for SBI STA. V6 -> V7: Removed RISCV_SBI_STA_REG() macro addition and used existing 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 check_steal_time_uapi() function and added empty stub for RISC-V. Filled in RISC-V stub with STA alignment tests. (this patch) --- .../selftests/kvm/include/kvm_util_types.h | 4 +++ tools/testing/selftests/kvm/steal_time.c | 25 +++++++++++++++++++ 2 files changed, 29 insertions(+) diff --git a/tools/testing/selftests/kvm/include/kvm_util_types.h b/tools/t= esting/selftests/kvm/include/kvm_util_types.h index ec787b97cf184..90567f8243fe9 100644 --- a/tools/testing/selftests/kvm/include/kvm_util_types.h +++ b/tools/testing/selftests/kvm/include/kvm_util_types.h @@ -17,4 +17,8 @@ typedef uint64_t vm_paddr_t; /* Virtual Machine (Guest) physical address */ typedef uint64_t vm_vaddr_t; /* Virtual Machine (Guest) virtual address */ =20 +#if defined(__riscv) +#define INVALID_GPA (~(uint64_t)0) +#endif + #endif /* SELFTEST_KVM_UTIL_TYPES_H */ diff --git a/tools/testing/selftests/kvm/steal_time.c b/tools/testing/selft= ests/kvm/steal_time.c index 6f77df4deaad3..e90aad9561ff7 100644 --- a/tools/testing/selftests/kvm/steal_time.c +++ b/tools/testing/selftests/kvm/steal_time.c @@ -324,6 +324,31 @@ static void steal_time_dump(struct kvm_vm *vm, uint32_= t vcpu_idx) =20 static void check_steal_time_uapi(struct kvm_vcpu *vcpu) { + struct kvm_one_reg reg; + uint64_t shmem; + int ret; + + reg.id =3D KVM_REG_RISCV | + KVM_REG_SIZE_ULONG | + KVM_REG_RISCV_SBI_STATE | + KVM_REG_RISCV_SBI_STA | + KVM_REG_RISCV_SBI_STA_REG(shmem_lo); + reg.addr =3D (uint64_t)&shmem; + + 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"); + + shmem =3D ST_GPA_BASE; + ret =3D __vcpu_ioctl(vcpu, KVM_SET_ONE_REG, ®); + TEST_ASSERT(ret =3D=3D 0, + "aligned STA shmem succeeds"); + + 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