From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wm1-f73.google.com (mail-wm1-f73.google.com [209.85.128.73]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DFC643A6F15 for ; Fri, 1 May 2026 11:20:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.73 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777634438; cv=none; b=TSu4yq9FsAQd5EpAXE26vrQtNHcAbmP4ZVVdBUN0UeaItlYN5t6NkwLZZ5juHhumxGmXY5Y0HKWBj0NXKMziJwiaVyix16tM5+6V+umFEHPirWbMXNwC8hsmUxgNL+S6+EiCeeOyk/f+O52rn0kvJWXITdVcNrflzdGsVGzkw6U= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777634438; c=relaxed/simple; bh=K0ptwM46SUnUhZWwfceVEOB6BIJZjEKLOxtcjcGQS/U=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=kbVY4uHOowiHRejrVNnCod+DVHooMsD6zGIvV+FFdAL9KLCCquY2Gb2boFDPK3HAvVbBSbi5dWbHxnDZiDNl3bzDMnPHebZZBl9TxTdNdBsl/3/W65ncypZi/pvJuI02TZgbI1JqKAh23jqF7L1nwHHvj23ROz9kERVybh2VHs8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--smostafa.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=ZptM7gQ9; arc=none smtp.client-ip=209.85.128.73 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--smostafa.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="ZptM7gQ9" Received: by mail-wm1-f73.google.com with SMTP id 5b1f17b1804b1-4837b6f6b93so21239985e9.3 for ; Fri, 01 May 2026 04:20:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1777634434; x=1778239234; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=cBYFLa+FC4uonW8niogdkcZuL7rcf529F6haDy+QJc8=; b=ZptM7gQ9DQvKX0kG1Jj+Y6RyAnWQMqzPgi4el7rmPKmC/ScqrwNqwTWC7jbZyJwbiI XU/AeYwsojbXQhtQxN+LVzG0Q794I934rzFwj7taHPs0Prrv41HrfF5i6VYPK4Ia8Ng3 8yp50uk+IS7QmG7sbHHynmGtt/6My9bF4bAG0mb8IIPcDikfvioU4qBzwcwmKp4cJT8G HPybqVDDNIgaEnDHHDT+DrXlS/q8w91O0ST9T6vRlsdkg8uN2ROpNwlxYGCMCpny1O3f CVFGHt+yMXwjvHKIg0Bf2tmkCW/u2qBP0dPIaOWfh04AGG4jmu7iTs3F+OIXJSyA0j/Y ORFg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1777634434; x=1778239234; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=cBYFLa+FC4uonW8niogdkcZuL7rcf529F6haDy+QJc8=; b=IREvIcKBfu5eq1xvGCjuGtLSQSbxiGLVGFwD/27RDmywXJ21V7y6gmmXW3PM0mmqyZ RGI5M1VE0MSCZLexBmDBy4spJhBHYBtVFjm1e6jarogfYDIxgRDlzRF1XZ1iH96CDTBu uce1x1wb5JbVhpU8mZOZcvp46VXG0+pxomcOJ7+Asibo0UQJZCeQLqPyTOD2oIbfUJ/D nNPIDPddluMxelVXIWySa1Q8yt6Ty0CKPajac9J/I5ViKZ/MTWfyhKE4Wkq5olW7HCSl SzvmDB7HuFoEqShp8q/qWlGMU/HVPXX5O/2tQM3mpKfkNfKse9bZeznX1NdBS8TOOSzD vSIA== X-Forwarded-Encrypted: i=1; AFNElJ82/E1n8GQ8ylrwXGWlTMRvXDMBBWfSiGl5bmgiRnRNvGZynxfJa3s+JgqcYPntDdTADsC4wigSYAHVYAY=@vger.kernel.org X-Gm-Message-State: AOJu0YyJh9P1QrH0paudR35g62gHQPkIQIAVG4qPGr0yBRBEJL+TLiHi aWiYkHhgEWp/Va7yWpkfQXdFdQldJv/cBNnQ9QNusDdAqAw7aYovJ0MvBY0yT8Ea5UJYFFHUkUz FSrpbionLWM5JNQ== X-Received: from wmrk12.prod.google.com ([2002:a05:600c:b4c:b0:489:1dcf:1b38]) (user=smostafa job=prod-delivery.src-stubby-dispatcher) by 2002:a05:600c:4588:b0:488:ab1d:dcc5 with SMTP id 5b1f17b1804b1-48a8447f4e9mr111938855e9.27.1777634434360; Fri, 01 May 2026 04:20:34 -0700 (PDT) Date: Fri, 1 May 2026 11:19:26 +0000 In-Reply-To: <20260501111928.259252-1-smostafa@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260501111928.259252-1-smostafa@google.com> X-Mailer: git-send-email 2.54.0.545.g6539524ca2-goog Message-ID: <20260501111928.259252-25-smostafa@google.com> Subject: [PATCH v6 24/25] iommu/arm-smmu-v3-kvm: Enable nesting From: Mostafa Saleh To: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, kvmarm@lists.linux.dev, iommu@lists.linux.dev Cc: catalin.marinas@arm.com, will@kernel.org, maz@kernel.org, oliver.upton@linux.dev, joey.gouly@arm.com, suzuki.poulose@arm.com, yuzenghui@huawei.com, joro@8bytes.org, jean-philippe@linaro.org, jgg@ziepe.ca, mark.rutland@arm.com, qperret@google.com, tabba@google.com, vdonnefort@google.com, sebastianene@google.com, keirf@google.com, Mostafa Saleh Content-Type: text/plain; charset="UTF-8" Now, as the hypervisor controls the command queue, stream table, and shadows the stage-2 page table. Enable stage-2 in case the host puts an STE in bypass or stage-1. Signed-off-by: Mostafa Saleh --- .../iommu/arm/arm-smmu-v3/pkvm/arm-smmu-v3.c | 108 ++++++++++++++++-- 1 file changed, 101 insertions(+), 7 deletions(-) diff --git a/drivers/iommu/arm/arm-smmu-v3/pkvm/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/pkvm/arm-smmu-v3.c index b73a2462f0dd..3d727d6dfbf0 100644 --- a/drivers/iommu/arm/arm-smmu-v3/pkvm/arm-smmu-v3.c +++ b/drivers/iommu/arm/arm-smmu-v3/pkvm/arm-smmu-v3.c @@ -411,6 +411,57 @@ static int smmu_init_cmdq(struct hyp_arm_smmu_v3_device *smmu) return 0; } +static int smmu_attach_stage_2(struct arm_smmu_ste *ste) +{ + unsigned long vttbr; + unsigned long ts, sl, ic, oc, sh, tg, ps; + unsigned long cfg; + struct io_pgtable_cfg *pgt_cfg = &idmap_pgtable->cfg; + + cfg = FIELD_GET(STRTAB_STE_0_CFG, le64_to_cpu(ste->data[0])); + if (!FIELD_GET(STRTAB_STE_0_V, le64_to_cpu(ste->data[0])) || + (cfg == STRTAB_STE_0_CFG_ABORT)) { + ste->data[2] = 0; + ste->data[3] = 0; + return 0; + } + /* S2 is not advertised, that should never be attempted. */ + if (cfg == STRTAB_STE_0_CFG_NESTED) + return -EINVAL; + vttbr = pgt_cfg->arm_lpae_s2_cfg.vttbr; + ps = pgt_cfg->arm_lpae_s2_cfg.vtcr.ps; + tg = pgt_cfg->arm_lpae_s2_cfg.vtcr.tg; + sh = pgt_cfg->arm_lpae_s2_cfg.vtcr.sh; + oc = pgt_cfg->arm_lpae_s2_cfg.vtcr.orgn; + ic = pgt_cfg->arm_lpae_s2_cfg.vtcr.irgn; + sl = pgt_cfg->arm_lpae_s2_cfg.vtcr.sl; + ts = pgt_cfg->arm_lpae_s2_cfg.vtcr.tsz; + + ste->data[1] &= ~cpu_to_le64(STRTAB_STE_1_SHCFG); + ste->data[1] |= cpu_to_le64(FIELD_PREP(STRTAB_STE_1_SHCFG, STRTAB_STE_1_SHCFG_INCOMING)); + + /* The host shouldn't write dwords 2 and 3, overwrite them. */ + ste->data[2] = cpu_to_le64(FIELD_PREP(STRTAB_STE_2_VTCR, + FIELD_PREP(STRTAB_STE_2_VTCR_S2PS, ps) | + FIELD_PREP(STRTAB_STE_2_VTCR_S2TG, tg) | + FIELD_PREP(STRTAB_STE_2_VTCR_S2SH0, sh) | + FIELD_PREP(STRTAB_STE_2_VTCR_S2OR0, oc) | + FIELD_PREP(STRTAB_STE_2_VTCR_S2IR0, ic) | + FIELD_PREP(STRTAB_STE_2_VTCR_S2SL0, sl) | + FIELD_PREP(STRTAB_STE_2_VTCR_S2T0SZ, ts)) | + FIELD_PREP(STRTAB_STE_2_S2VMID, 0) | + STRTAB_STE_2_S2AA64 | STRTAB_STE_2_S2R | + #ifdef __BIG_ENDIAN + STRTAB_STE_2_S2ENDI | +#endif + STRTAB_STE_2_S2PTW); + + ste->data[3] = cpu_to_le64(vttbr & STRTAB_STE_3_S2TTB_MASK); + /* Convert S1 => nested and bypass => S2 */ + ste->data[0] |= cpu_to_le64(FIELD_PREP(STRTAB_STE_0_CFG, cfg | BIT(1))); + return 0; +} + static int smmu_get_host_l2_ste(struct hyp_arm_smmu_v3_device *smmu, u32 sid, struct arm_smmu_ste *host_ste_out) { @@ -440,9 +491,18 @@ static int smmu_get_host_l2_ste(struct hyp_arm_smmu_v3_device *smmu, u32 sid, static int smmu_reshadow_ste(struct hyp_arm_smmu_v3_device *smmu, u32 sid, bool leaf) { struct arm_smmu_strtab_cfg *cfg = &smmu->strtab_cfg; - struct arm_smmu_ste *hyp_ste_ptr, *host_ste_ptr, host_ste_copy; + struct arm_smmu_ste *hyp_ste_ptr; u64 *hyp_ste_base = strtab_hyp_base(smmu); - int ret; + struct arm_smmu_ste target = {}; + struct arm_smmu_cmdq_ent cfgi_cmd = { + .opcode = CMDQ_OP_CFGI_STE, + .cfgi = { + .sid = sid, + .leaf = true, + }, + }; + bool cur_valid, target_valid; + int i, ret; /* * Linux only uses leaf = 1, when leaf is 0, we need to verify that this @@ -463,7 +523,7 @@ static int smmu_reshadow_ste(struct hyp_arm_smmu_v3_device *smmu, u32 sid, bool return -E2BIG; hyp_ste_ptr = &hyp_table[sid]; - host_ste_ptr = &host_table[sid]; + memcpy(target.data, host_table[sid].data, STRTAB_STE_DWORDS << 3); } else { struct arm_smmu_strtab_l1 *l1tab = (struct arm_smmu_strtab_l1 *)hyp_ste_base; u32 l1_idx = arm_smmu_strtab_l1_idx(sid); @@ -472,8 +532,7 @@ static int smmu_reshadow_ste(struct hyp_arm_smmu_v3_device *smmu, u32 sid, bool if (l1_idx >= cfg->l2.num_l1_ents) return -E2BIG; - host_ste_ptr = &host_ste_copy; - ret = smmu_get_host_l2_ste(smmu, sid, host_ste_ptr); + ret = smmu_get_host_l2_ste(smmu, sid, &target); if (ret) return ret; @@ -491,9 +550,44 @@ static int smmu_reshadow_ste(struct hyp_arm_smmu_v3_device *smmu, u32 sid, bool hyp_ste_ptr = &l2ptr->stes[arm_smmu_strtab_l2_idx(sid)]; } - memcpy(hyp_ste_ptr->data, host_ste_ptr->data, STRTAB_STE_DWORDS << 3); - return 0; + /* + * Summary of each host emulated state vs real HW. + * | Host | HW | + * ============================== + * | V=0 | V=0 | + * | Abort | Abort | + * | Bypass | S2 | + * | S1 | S1+S2 | + * + * For the host, any V=0 transition is not hitless, all other permutations of + * (abort, bypass, S1) transitions are hitless. + * For the HW state, any V=0 transition is not hitless, as all the S2 config is + * always the same (ttbr, vtcr...), all other transitions should be hitless too. + * However, the host is not trusted, which means that any V=0 <=> V=1 transitions + * we need to enforce writing order of the STE and add CFGI. + */ + cur_valid = FIELD_GET(STRTAB_STE_0_V, le64_to_cpu(hyp_ste_ptr->data[0])); + ret = smmu_attach_stage_2(&target); + if (ret) + return ret; + target_valid = FIELD_GET(STRTAB_STE_0_V, le64_to_cpu(target.data[0])); + if (cur_valid && !target_valid) { + WRITE_ONCE(hyp_ste_ptr->data[0], target.data[0]); + WARN_ON(smmu_send_cmd(smmu, &cfgi_cmd)); + for (i = 1; i < STRTAB_STE_DWORDS; i++) + WRITE_ONCE(hyp_ste_ptr->data[i], target.data[i]); + } else if (!cur_valid && target_valid) { + for (i = 1; i < STRTAB_STE_DWORDS; i++) + WRITE_ONCE(hyp_ste_ptr->data[i], target.data[i]); + WARN_ON(smmu_send_cmd(smmu, &cfgi_cmd)); + WRITE_ONCE(hyp_ste_ptr->data[0], target.data[0]); + } else { + for (i = 0; i < STRTAB_STE_DWORDS; i++) + WRITE_ONCE(hyp_ste_ptr->data[i], target.data[i]); + } + + return smmu_send_cmd(smmu, &cfgi_cmd); } static int smmu_init_strtab(struct hyp_arm_smmu_v3_device *smmu) -- 2.54.0.545.g6539524ca2-goog