From patchwork Mon Mar 10 12:24:51 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marc Zyngier X-Patchwork-Id: 14009833 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C88D6229B17; Mon, 10 Mar 2025 12:25:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741609514; cv=none; b=PGqEID2kSSGLlN8xmezhYQ8pO6BSXHGT1NgkF2nZMaIkWyM/dt71Ic8p0b2v8wHP5Ly4G3VA3/0P2SnwtIkI7XpjDQyCwKQnFF/1T7ZpNJ7BiR+ph6EMJTC/RkneTV9D/9I2Scb+kwNWuKyecJN6qzRbtxFyIJ3enhvzwpKAXog= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741609514; c=relaxed/simple; bh=f9XQRQuULxKzE9X/XvGWnwafyLw7l1Eqzg+ZWKrvZ6w=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=NjNBl5sSRKi1UJZbJwdg89PN2/2PyFIrPRT9byoe1T18ivHq5wCus0Q4XI5eFjcAqcbPcUVFyicfaRuujDBVf0EbGeNuFqtGPljAJKntsLkK1VKXBZzN3qSMgIPdpzpXcGPJPZ0j5uwZsFozqUnL+f71DbhbIKlPlanGO9iFk0M= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=r1C5CBBv; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="r1C5CBBv" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0E70DC4CEEF; Mon, 10 Mar 2025 12:25:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1741609514; bh=f9XQRQuULxKzE9X/XvGWnwafyLw7l1Eqzg+ZWKrvZ6w=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=r1C5CBBvJ0lnXDmq+fkEdQLccWMG17M6AVjrLEA5Xq+BQgXkbwfznqMH1pjmZffV+ /jQ9ZRg5INcWWvDI4IOczany+FrInaig04H2lFFEwKQ8IBh/AxXgHGHt15yj8CvJvx BmaAysa19gih6xUTabeMlWaGyQxVWIfqZoj0meeE4AIFqmHBywBlp44yy3g1JbVDkY e0U2gUsmDI6vWNBdZrINqlHN1VNBiCRpalDHmddGtmaQO728zySLEXjS++vBmkZ+VS kWjG0/ZtBHngnP7bdpCMB8K6XXIAMWRnU9ULomDEO7MIMXgBKk+OtNt0veP49qPxOQ 2YSb6kKISSexw== Received: from sofa.misterjones.org ([185.219.108.64] helo=valley-girl.lan) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.95) (envelope-from ) id 1trcC0-00CAea-6V; Mon, 10 Mar 2025 12:25:12 +0000 From: Marc Zyngier To: kvmarm@lists.linux.dev, kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org Cc: Joey Gouly , Suzuki K Poulose , Oliver Upton , Zenghui Yu , Mark Rutland , Fuad Tabba Subject: [PATCH v2 09/23] KVM: arm64: Compute FGT masks from KVM's own FGT tables Date: Mon, 10 Mar 2025 12:24:51 +0000 Message-Id: <20250310122505.2857610-10-maz@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20250310122505.2857610-1-maz@kernel.org> References: <20250310122505.2857610-1-maz@kernel.org> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: kvmarm@lists.linux.dev, kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, joey.gouly@arm.com, suzuki.poulose@arm.com, oliver.upton@linux.dev, yuzenghui@huawei.com, mark.rutland@arm.com, tabba@google.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false In the process of decoupling KVM's view of the FGT bits from the wider architectural state, use KVM's own FGT tables to build a synthitic view of what is actually known. This allows for some checking along the way. Signed-off-by: Marc Zyngier --- arch/arm64/include/asm/kvm_arm.h | 4 ++ arch/arm64/include/asm/kvm_host.h | 14 ++++ arch/arm64/kvm/emulate-nested.c | 102 ++++++++++++++++++++++++++++++ 3 files changed, 120 insertions(+) diff --git a/arch/arm64/include/asm/kvm_arm.h b/arch/arm64/include/asm/kvm_arm.h index 52bd4abc2a85d..9ff6fda07a68e 100644 --- a/arch/arm64/include/asm/kvm_arm.h +++ b/arch/arm64/include/asm/kvm_arm.h @@ -362,6 +362,10 @@ #define __HAFGRTR_EL2_MASK (GENMASK(49, 17) | GENMASK(4, 0)) #define __HAFGRTR_EL2_nMASK ~(__HAFGRTR_EL2_RES0 | __HAFGRTR_EL2_MASK) +/* Because the sysreg file mixes R and W... */ +#define HFGRTR_EL2_RES0 HFGxTR_EL2_RES0 +#define HFGWTR_EL2_RES0 (HFGRTR_EL2_RES0 | __HFGRTR_ONLY_MASK) + /* Similar definitions for HCRX_EL2 */ #define __HCRX_EL2_RES0 HCRX_EL2_RES0 #define __HCRX_EL2_MASK (BIT(6)) diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 3a7ec98ef1238..657fb8243ea63 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -569,6 +569,20 @@ struct kvm_sysreg_masks { } mask[NR_SYS_REGS - __SANITISED_REG_START__]; }; +struct fgt_masks { + const char *str; + u64 mask; + u64 nmask; + u64 res0; +}; + +extern struct fgt_masks hfgrtr_masks; +extern struct fgt_masks hfgwtr_masks; +extern struct fgt_masks hfgitr_masks; +extern struct fgt_masks hdfgrtr_masks; +extern struct fgt_masks hdfgwtr_masks; +extern struct fgt_masks hafgrtr_masks; + struct kvm_cpu_context { struct user_pt_regs regs; /* sp = sp_el0 */ diff --git a/arch/arm64/kvm/emulate-nested.c b/arch/arm64/kvm/emulate-nested.c index 607d37bab70b4..bbfe89c37a86e 100644 --- a/arch/arm64/kvm/emulate-nested.c +++ b/arch/arm64/kvm/emulate-nested.c @@ -2033,6 +2033,101 @@ static u32 encoding_next(u32 encoding) return sys_reg(op0 + 1, 0, 0, 0, 0); } +#define FGT_MASKS(__n, __m) \ + struct fgt_masks __n = { .str = #__m, .res0 = __m, } + +FGT_MASKS(hfgrtr_masks, HFGRTR_EL2_RES0); +FGT_MASKS(hfgwtr_masks, HFGWTR_EL2_RES0); +FGT_MASKS(hfgitr_masks, HFGITR_EL2_RES0); +FGT_MASKS(hdfgrtr_masks, HDFGRTR_EL2_RES0); +FGT_MASKS(hdfgwtr_masks, HDFGWTR_EL2_RES0); +FGT_MASKS(hafgrtr_masks, HAFGRTR_EL2_RES0); + +static __init bool aggregate_fgt(union trap_config tc) +{ + struct fgt_masks *rmasks, *wmasks; + + switch (tc.fgt) { + case HFGxTR_GROUP: + rmasks = &hfgrtr_masks; + wmasks = &hfgwtr_masks; + break; + case HDFGRTR_GROUP: + rmasks = &hdfgrtr_masks; + wmasks = &hdfgwtr_masks; + break; + case HAFGRTR_GROUP: + rmasks = &hafgrtr_masks; + wmasks = NULL; + break; + case HFGITR_GROUP: + rmasks = &hfgitr_masks; + wmasks = NULL; + break; + } + + /* + * A bit can be reserved in either the R or W register, but + * not both. + */ + if ((BIT(tc.bit) & rmasks->res0) && + (!wmasks || (BIT(tc.bit) & wmasks->res0))) + return false; + + if (tc.pol) + rmasks->mask |= BIT(tc.bit) & ~rmasks->res0; + else + rmasks->nmask |= BIT(tc.bit) & ~rmasks->res0; + + if (wmasks) { + if (tc.pol) + wmasks->mask |= BIT(tc.bit) & ~wmasks->res0; + else + wmasks->nmask |= BIT(tc.bit) & ~wmasks->res0; + } + + return true; +} + +static __init int check_fgt_masks(struct fgt_masks *masks) +{ + unsigned long duplicate = masks->mask & masks->nmask; + u64 res0 = masks->res0; + int ret = 0; + + if (duplicate) { + int i; + + for_each_set_bit(i, &duplicate, 64) { + kvm_err("%s[%d] bit has both polarities\n", + masks->str, i); + } + + ret = -EINVAL; + } + + masks->res0 = ~(masks->mask | masks->nmask); + if (masks->res0 != res0) + kvm_info("Implicit %s = %016llx, expecting %016llx\n", + masks->str, masks->res0, res0); + + return ret; +} + +static __init int check_all_fgt_masks(int ret) +{ + int err = 0; + + err |= check_fgt_masks(&hfgrtr_masks); + err |= check_fgt_masks(&hfgwtr_masks); + err |= check_fgt_masks(&hfgitr_masks); + err |= check_fgt_masks(&hdfgrtr_masks); + err |= check_fgt_masks(&hdfgwtr_masks); + err |= check_fgt_masks(&hafgrtr_masks); + + return ret ?: err; +} + int __init populate_nv_trap_config(void) { int ret = 0; @@ -2097,8 +2192,15 @@ int __init populate_nv_trap_config(void) ret = xa_err(prev); print_nv_trap_error(fgt, "Failed FGT insertion", ret); } + + if (!aggregate_fgt(tc)) { + ret = -EINVAL; + print_nv_trap_error(fgt, "FGT bit is reserved", ret); + } } + ret = check_all_fgt_masks(ret); + kvm_info("nv: %ld fine grained trap handlers\n", ARRAY_SIZE(encoding_to_fgt));