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authorCatalin Marinas <catalin.marinas@arm.com>2023-06-23 18:34:16 +0100
committerCatalin Marinas <catalin.marinas@arm.com>2023-06-23 18:34:16 +0100
commitabc17128c81ae8d6a091f24348c63cbe8fe59724 (patch)
tree90dc9c2268fc399b0aa812cab6e223859720a741 /arch/arm64/include/asm
parentf42039d10b0f1d0075568df1d64df31f5cc90e92 (diff)
parent5f0419a0083b304566fa32c27a0f009634a7f703 (diff)
Merge branch 'for-next/feat_s1pie' into for-next/core
* for-next/feat_s1pie: : Support for the Armv8.9 Permission Indirection Extensions (stage 1 only) KVM: selftests: get-reg-list: add Permission Indirection registers KVM: selftests: get-reg-list: support ID register features arm64: Document boot requirements for PIE arm64: transfer permission indirection settings to EL2 arm64: enable Permission Indirection Extension (PIE) arm64: add encodings of PIRx_ELx registers arm64: disable EL2 traps for PIE arm64: reorganise PAGE_/PROT_ macros arm64: add PTE_WRITE to PROT_SECT_NORMAL arm64: add PTE_UXN/PTE_WRITE to SWAPPER_*_FLAGS KVM: arm64: expose ID_AA64MMFR3_EL1 to guests KVM: arm64: Save/restore PIE registers KVM: arm64: Save/restore TCR2_EL1 arm64: cpufeature: add Permission Indirection Extension cpucap arm64: cpufeature: add TCR2 cpucap arm64: cpufeature: add system register ID_AA64MMFR3 arm64/sysreg: add PIR*_ELx registers arm64/sysreg: update HCRX_EL2 register arm64/sysreg: add system registers TCR2_ELx arm64/sysreg: Add ID register ID_AA64MMFR3
Diffstat (limited to 'arch/arm64/include/asm')
-rw-r--r--arch/arm64/include/asm/cpu.h1
-rw-r--r--arch/arm64/include/asm/el2_setup.h11
-rw-r--r--arch/arm64/include/asm/kernel-pgtable.h8
-rw-r--r--arch/arm64/include/asm/kvm_arm.h4
-rw-r--r--arch/arm64/include/asm/kvm_host.h5
-rw-r--r--arch/arm64/include/asm/pgtable-hwdef.h8
-rw-r--r--arch/arm64/include/asm/pgtable-prot.h122
-rw-r--r--arch/arm64/include/asm/sysreg.h19
8 files changed, 143 insertions, 35 deletions
diff --git a/arch/arm64/include/asm/cpu.h b/arch/arm64/include/asm/cpu.h
index fd7a92219eea..e749838b9c5d 100644
--- a/arch/arm64/include/asm/cpu.h
+++ b/arch/arm64/include/asm/cpu.h
@@ -56,6 +56,7 @@ struct cpuinfo_arm64 {
u64 reg_id_aa64mmfr0;
u64 reg_id_aa64mmfr1;
u64 reg_id_aa64mmfr2;
+ u64 reg_id_aa64mmfr3;
u64 reg_id_aa64pfr0;
u64 reg_id_aa64pfr1;
u64 reg_id_aa64zfr0;
diff --git a/arch/arm64/include/asm/el2_setup.h b/arch/arm64/include/asm/el2_setup.h
index 96440c7f2a84..f4c3d30bf746 100644
--- a/arch/arm64/include/asm/el2_setup.h
+++ b/arch/arm64/include/asm/el2_setup.h
@@ -159,12 +159,21 @@
mov x0, xzr
mrs x1, id_aa64pfr1_el1
ubfx x1, x1, #ID_AA64PFR1_EL1_SME_SHIFT, #4
- cbz x1, .Lset_fgt_\@
+ cbz x1, .Lset_pie_fgt_\@
/* Disable nVHE traps of TPIDR2 and SMPRI */
orr x0, x0, #HFGxTR_EL2_nSMPRI_EL1_MASK
orr x0, x0, #HFGxTR_EL2_nTPIDR2_EL0_MASK
+.Lset_pie_fgt_\@:
+ mrs_s x1, SYS_ID_AA64MMFR3_EL1
+ ubfx x1, x1, #ID_AA64MMFR3_EL1_S1PIE_SHIFT, #4
+ cbz x1, .Lset_fgt_\@
+
+ /* Disable trapping of PIR_EL1 / PIRE0_EL1 */
+ orr x0, x0, #HFGxTR_EL2_nPIR_EL1
+ orr x0, x0, #HFGxTR_EL2_nPIRE0_EL1
+
.Lset_fgt_\@:
msr_s SYS_HFGRTR_EL2, x0
msr_s SYS_HFGWTR_EL2, x0
diff --git a/arch/arm64/include/asm/kernel-pgtable.h b/arch/arm64/include/asm/kernel-pgtable.h
index 186dd7f85b14..577773870b66 100644
--- a/arch/arm64/include/asm/kernel-pgtable.h
+++ b/arch/arm64/include/asm/kernel-pgtable.h
@@ -107,14 +107,14 @@
/*
* Initial memory map attributes.
*/
-#define SWAPPER_PTE_FLAGS (PTE_TYPE_PAGE | PTE_AF | PTE_SHARED)
-#define SWAPPER_PMD_FLAGS (PMD_TYPE_SECT | PMD_SECT_AF | PMD_SECT_S)
+#define SWAPPER_PTE_FLAGS (PTE_TYPE_PAGE | PTE_AF | PTE_SHARED | PTE_UXN)
+#define SWAPPER_PMD_FLAGS (PMD_TYPE_SECT | PMD_SECT_AF | PMD_SECT_S | PTE_UXN)
#ifdef CONFIG_ARM64_4K_PAGES
-#define SWAPPER_RW_MMUFLAGS (PMD_ATTRINDX(MT_NORMAL) | SWAPPER_PMD_FLAGS)
+#define SWAPPER_RW_MMUFLAGS (PMD_ATTRINDX(MT_NORMAL) | SWAPPER_PMD_FLAGS | PTE_WRITE)
#define SWAPPER_RX_MMUFLAGS (SWAPPER_RW_MMUFLAGS | PMD_SECT_RDONLY)
#else
-#define SWAPPER_RW_MMUFLAGS (PTE_ATTRINDX(MT_NORMAL) | SWAPPER_PTE_FLAGS)
+#define SWAPPER_RW_MMUFLAGS (PTE_ATTRINDX(MT_NORMAL) | SWAPPER_PTE_FLAGS | PTE_WRITE)
#define SWAPPER_RX_MMUFLAGS (SWAPPER_RW_MMUFLAGS | PTE_RDONLY)
#endif
diff --git a/arch/arm64/include/asm/kvm_arm.h b/arch/arm64/include/asm/kvm_arm.h
index d2d4f4cd12b8..c6e12e8f2751 100644
--- a/arch/arm64/include/asm/kvm_arm.h
+++ b/arch/arm64/include/asm/kvm_arm.h
@@ -93,8 +93,8 @@
#define HCR_HOST_NVHE_PROTECTED_FLAGS (HCR_HOST_NVHE_FLAGS | HCR_TSC)
#define HCR_HOST_VHE_FLAGS (HCR_RW | HCR_TGE | HCR_E2H)
-#define HCRX_GUEST_FLAGS (HCRX_EL2_SMPME)
-#define HCRX_HOST_FLAGS (HCRX_EL2_MSCEn)
+#define HCRX_GUEST_FLAGS (HCRX_EL2_SMPME | HCRX_EL2_TCR2En)
+#define HCRX_HOST_FLAGS (HCRX_EL2_MSCEn | HCRX_EL2_TCR2En)
/* TCR_EL2 Registers bits */
#define TCR_EL2_RES1 ((1U << 31) | (1 << 23))
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index e759e6b0cd02..8dbe8d8f7d7a 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -279,6 +279,7 @@ enum vcpu_sysreg {
TTBR0_EL1, /* Translation Table Base Register 0 */
TTBR1_EL1, /* Translation Table Base Register 1 */
TCR_EL1, /* Translation Control Register */
+ TCR2_EL1, /* Extended Translation Control Register */
ESR_EL1, /* Exception Syndrome Register */
AFSR0_EL1, /* Auxiliary Fault Status Register 0 */
AFSR1_EL1, /* Auxiliary Fault Status Register 1 */
@@ -339,6 +340,10 @@ enum vcpu_sysreg {
TFSR_EL1, /* Tag Fault Status Register (EL1) */
TFSRE0_EL1, /* Tag Fault Status Register (EL0) */
+ /* Permission Indirection Extension registers */
+ PIR_EL1, /* Permission Indirection Register 1 (EL1) */
+ PIRE0_EL1, /* Permission Indirection Register 0 (EL1) */
+
/* 32bit specific registers. */
DACR32_EL2, /* Domain Access Control Register */
IFSR32_EL2, /* Instruction Fault Status Register */
diff --git a/arch/arm64/include/asm/pgtable-hwdef.h b/arch/arm64/include/asm/pgtable-hwdef.h
index f658aafc47df..e4944d517c99 100644
--- a/arch/arm64/include/asm/pgtable-hwdef.h
+++ b/arch/arm64/include/asm/pgtable-hwdef.h
@@ -171,6 +171,14 @@
#define PTE_ATTRINDX_MASK (_AT(pteval_t, 7) << 2)
/*
+ * PIIndex[3:0] encoding (Permission Indirection Extension)
+ */
+#define PTE_PI_IDX_0 6 /* AP[1], USER */
+#define PTE_PI_IDX_1 51 /* DBM */
+#define PTE_PI_IDX_2 53 /* PXN */
+#define PTE_PI_IDX_3 54 /* UXN */
+
+/*
* Memory Attribute override for Stage-2 (MemAttr[3:0])
*/
#define PTE_S2_MEMATTR(t) (_AT(pteval_t, (t)) << 2)
diff --git a/arch/arm64/include/asm/pgtable-prot.h b/arch/arm64/include/asm/pgtable-prot.h
index 9b165117a454..eed814b00a38 100644
--- a/arch/arm64/include/asm/pgtable-prot.h
+++ b/arch/arm64/include/asm/pgtable-prot.h
@@ -27,6 +27,40 @@
*/
#define PMD_PRESENT_INVALID (_AT(pteval_t, 1) << 59) /* only when !PMD_SECT_VALID */
+#define _PROT_DEFAULT (PTE_TYPE_PAGE | PTE_AF | PTE_SHARED)
+#define _PROT_SECT_DEFAULT (PMD_TYPE_SECT | PMD_SECT_AF | PMD_SECT_S)
+
+#define PROT_DEFAULT (_PROT_DEFAULT | PTE_MAYBE_NG)
+#define PROT_SECT_DEFAULT (_PROT_SECT_DEFAULT | PMD_MAYBE_NG)
+
+#define PROT_DEVICE_nGnRnE (PROT_DEFAULT | PTE_PXN | PTE_UXN | PTE_WRITE | PTE_ATTRINDX(MT_DEVICE_nGnRnE))
+#define PROT_DEVICE_nGnRE (PROT_DEFAULT | PTE_PXN | PTE_UXN | PTE_WRITE | PTE_ATTRINDX(MT_DEVICE_nGnRE))
+#define PROT_NORMAL_NC (PROT_DEFAULT | PTE_PXN | PTE_UXN | PTE_WRITE | PTE_ATTRINDX(MT_NORMAL_NC))
+#define PROT_NORMAL (PROT_DEFAULT | PTE_PXN | PTE_UXN | PTE_WRITE | PTE_ATTRINDX(MT_NORMAL))
+#define PROT_NORMAL_TAGGED (PROT_DEFAULT | PTE_PXN | PTE_UXN | PTE_WRITE | PTE_ATTRINDX(MT_NORMAL_TAGGED))
+
+#define PROT_SECT_DEVICE_nGnRE (PROT_SECT_DEFAULT | PMD_SECT_PXN | PMD_SECT_UXN | PMD_ATTRINDX(MT_DEVICE_nGnRE))
+#define PROT_SECT_NORMAL (PROT_SECT_DEFAULT | PMD_SECT_PXN | PMD_SECT_UXN | PTE_WRITE | PMD_ATTRINDX(MT_NORMAL))
+#define PROT_SECT_NORMAL_EXEC (PROT_SECT_DEFAULT | PMD_SECT_UXN | PMD_ATTRINDX(MT_NORMAL))
+
+#define _PAGE_DEFAULT (_PROT_DEFAULT | PTE_ATTRINDX(MT_NORMAL))
+
+#define _PAGE_KERNEL (PROT_NORMAL)
+#define _PAGE_KERNEL_RO ((PROT_NORMAL & ~PTE_WRITE) | PTE_RDONLY)
+#define _PAGE_KERNEL_ROX ((PROT_NORMAL & ~(PTE_WRITE | PTE_PXN)) | PTE_RDONLY)
+#define _PAGE_KERNEL_EXEC (PROT_NORMAL & ~PTE_PXN)
+#define _PAGE_KERNEL_EXEC_CONT ((PROT_NORMAL & ~PTE_PXN) | PTE_CONT)
+
+#define _PAGE_SHARED (_PAGE_DEFAULT | PTE_USER | PTE_RDONLY | PTE_NG | PTE_PXN | PTE_UXN | PTE_WRITE)
+#define _PAGE_SHARED_EXEC (_PAGE_DEFAULT | PTE_USER | PTE_RDONLY | PTE_NG | PTE_PXN | PTE_WRITE)
+#define _PAGE_READONLY (_PAGE_DEFAULT | PTE_USER | PTE_RDONLY | PTE_NG | PTE_PXN | PTE_UXN)
+#define _PAGE_READONLY_EXEC (_PAGE_DEFAULT | PTE_USER | PTE_RDONLY | PTE_NG | PTE_PXN)
+#define _PAGE_EXECONLY (_PAGE_DEFAULT | PTE_RDONLY | PTE_NG | PTE_PXN)
+
+#ifdef __ASSEMBLY__
+#define PTE_MAYBE_NG 0
+#endif
+
#ifndef __ASSEMBLY__
#include <asm/cpufeature.h>
@@ -34,9 +68,6 @@
extern bool arm64_use_ng_mappings;
-#define _PROT_DEFAULT (PTE_TYPE_PAGE | PTE_AF | PTE_SHARED)
-#define _PROT_SECT_DEFAULT (PMD_TYPE_SECT | PMD_SECT_AF | PMD_SECT_S)
-
#define PTE_MAYBE_NG (arm64_use_ng_mappings ? PTE_NG : 0)
#define PMD_MAYBE_NG (arm64_use_ng_mappings ? PMD_SECT_NG : 0)
@@ -50,26 +81,11 @@ extern bool arm64_use_ng_mappings;
#define PTE_MAYBE_GP 0
#endif
-#define PROT_DEFAULT (_PROT_DEFAULT | PTE_MAYBE_NG)
-#define PROT_SECT_DEFAULT (_PROT_SECT_DEFAULT | PMD_MAYBE_NG)
-
-#define PROT_DEVICE_nGnRnE (PROT_DEFAULT | PTE_PXN | PTE_UXN | PTE_WRITE | PTE_ATTRINDX(MT_DEVICE_nGnRnE))
-#define PROT_DEVICE_nGnRE (PROT_DEFAULT | PTE_PXN | PTE_UXN | PTE_WRITE | PTE_ATTRINDX(MT_DEVICE_nGnRE))
-#define PROT_NORMAL_NC (PROT_DEFAULT | PTE_PXN | PTE_UXN | PTE_WRITE | PTE_ATTRINDX(MT_NORMAL_NC))
-#define PROT_NORMAL (PROT_DEFAULT | PTE_PXN | PTE_UXN | PTE_WRITE | PTE_ATTRINDX(MT_NORMAL))
-#define PROT_NORMAL_TAGGED (PROT_DEFAULT | PTE_PXN | PTE_UXN | PTE_WRITE | PTE_ATTRINDX(MT_NORMAL_TAGGED))
-
-#define PROT_SECT_DEVICE_nGnRE (PROT_SECT_DEFAULT | PMD_SECT_PXN | PMD_SECT_UXN | PMD_ATTRINDX(MT_DEVICE_nGnRE))
-#define PROT_SECT_NORMAL (PROT_SECT_DEFAULT | PMD_SECT_PXN | PMD_SECT_UXN | PMD_ATTRINDX(MT_NORMAL))
-#define PROT_SECT_NORMAL_EXEC (PROT_SECT_DEFAULT | PMD_SECT_UXN | PMD_ATTRINDX(MT_NORMAL))
-
-#define _PAGE_DEFAULT (_PROT_DEFAULT | PTE_ATTRINDX(MT_NORMAL))
-
-#define PAGE_KERNEL __pgprot(PROT_NORMAL)
-#define PAGE_KERNEL_RO __pgprot((PROT_NORMAL & ~PTE_WRITE) | PTE_RDONLY)
-#define PAGE_KERNEL_ROX __pgprot((PROT_NORMAL & ~(PTE_WRITE | PTE_PXN)) | PTE_RDONLY)
-#define PAGE_KERNEL_EXEC __pgprot(PROT_NORMAL & ~PTE_PXN)
-#define PAGE_KERNEL_EXEC_CONT __pgprot((PROT_NORMAL & ~PTE_PXN) | PTE_CONT)
+#define PAGE_KERNEL __pgprot(_PAGE_KERNEL)
+#define PAGE_KERNEL_RO __pgprot(_PAGE_KERNEL_RO)
+#define PAGE_KERNEL_ROX __pgprot(_PAGE_KERNEL_ROX)
+#define PAGE_KERNEL_EXEC __pgprot(_PAGE_KERNEL_EXEC)
+#define PAGE_KERNEL_EXEC_CONT __pgprot(_PAGE_KERNEL_EXEC_CONT)
#define PAGE_S2_MEMATTR(attr, has_fwb) \
({ \
@@ -83,12 +99,62 @@ extern bool arm64_use_ng_mappings;
#define PAGE_NONE __pgprot(((_PAGE_DEFAULT) & ~PTE_VALID) | PTE_PROT_NONE | PTE_RDONLY | PTE_NG | PTE_PXN | PTE_UXN)
/* shared+writable pages are clean by default, hence PTE_RDONLY|PTE_WRITE */
-#define PAGE_SHARED __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_RDONLY | PTE_NG | PTE_PXN | PTE_UXN | PTE_WRITE)
-#define PAGE_SHARED_EXEC __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_RDONLY | PTE_NG | PTE_PXN | PTE_WRITE)
-#define PAGE_READONLY __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_RDONLY | PTE_NG | PTE_PXN | PTE_UXN)
-#define PAGE_READONLY_EXEC __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_RDONLY | PTE_NG | PTE_PXN)
-#define PAGE_EXECONLY __pgprot(_PAGE_DEFAULT | PTE_RDONLY | PTE_NG | PTE_PXN)
+#define PAGE_SHARED __pgprot(_PAGE_SHARED)
+#define PAGE_SHARED_EXEC __pgprot(_PAGE_SHARED_EXEC)
+#define PAGE_READONLY __pgprot(_PAGE_READONLY)
+#define PAGE_READONLY_EXEC __pgprot(_PAGE_READONLY_EXEC)
+#define PAGE_EXECONLY __pgprot(_PAGE_EXECONLY)
#endif /* __ASSEMBLY__ */
+#define pte_pi_index(pte) ( \
+ ((pte & BIT(PTE_PI_IDX_3)) >> (PTE_PI_IDX_3 - 3)) | \
+ ((pte & BIT(PTE_PI_IDX_2)) >> (PTE_PI_IDX_2 - 2)) | \
+ ((pte & BIT(PTE_PI_IDX_1)) >> (PTE_PI_IDX_1 - 1)) | \
+ ((pte & BIT(PTE_PI_IDX_0)) >> (PTE_PI_IDX_0 - 0)))
+
+/*
+ * Page types used via Permission Indirection Extension (PIE). PIE uses
+ * the USER, DBM, PXN and UXN bits to to generate an index which is used
+ * to look up the actual permission in PIR_ELx and PIRE0_EL1. We define
+ * combinations we use on non-PIE systems with the same encoding, for
+ * convenience these are listed here as comments as are the unallocated
+ * encodings.
+ */
+
+/* 0: PAGE_DEFAULT */
+/* 1: PTE_USER */
+/* 2: PTE_WRITE */
+/* 3: PTE_WRITE | PTE_USER */
+/* 4: PAGE_EXECONLY PTE_PXN */
+/* 5: PAGE_READONLY_EXEC PTE_PXN | PTE_USER */
+/* 6: PTE_PXN | PTE_WRITE */
+/* 7: PAGE_SHARED_EXEC PTE_PXN | PTE_WRITE | PTE_USER */
+/* 8: PAGE_KERNEL_ROX PTE_UXN */
+/* 9: PTE_UXN | PTE_USER */
+/* a: PAGE_KERNEL_EXEC PTE_UXN | PTE_WRITE */
+/* b: PTE_UXN | PTE_WRITE | PTE_USER */
+/* c: PAGE_KERNEL_RO PTE_UXN | PTE_PXN */
+/* d: PAGE_READONLY PTE_UXN | PTE_PXN | PTE_USER */
+/* e: PAGE_KERNEL PTE_UXN | PTE_PXN | PTE_WRITE */
+/* f: PAGE_SHARED PTE_UXN | PTE_PXN | PTE_WRITE | PTE_USER */
+
+#define PIE_E0 ( \
+ PIRx_ELx_PERM(pte_pi_index(_PAGE_EXECONLY), PIE_X_O) | \
+ PIRx_ELx_PERM(pte_pi_index(_PAGE_READONLY_EXEC), PIE_RX) | \
+ PIRx_ELx_PERM(pte_pi_index(_PAGE_SHARED_EXEC), PIE_RWX) | \
+ PIRx_ELx_PERM(pte_pi_index(_PAGE_READONLY), PIE_R) | \
+ PIRx_ELx_PERM(pte_pi_index(_PAGE_SHARED), PIE_RW))
+
+#define PIE_E1 ( \
+ PIRx_ELx_PERM(pte_pi_index(_PAGE_EXECONLY), PIE_NONE_O) | \
+ PIRx_ELx_PERM(pte_pi_index(_PAGE_READONLY_EXEC), PIE_R) | \
+ PIRx_ELx_PERM(pte_pi_index(_PAGE_SHARED_EXEC), PIE_RW) | \
+ PIRx_ELx_PERM(pte_pi_index(_PAGE_READONLY), PIE_R) | \
+ PIRx_ELx_PERM(pte_pi_index(_PAGE_SHARED), PIE_RW) | \
+ PIRx_ELx_PERM(pte_pi_index(_PAGE_KERNEL_ROX), PIE_RX) | \
+ PIRx_ELx_PERM(pte_pi_index(_PAGE_KERNEL_EXEC), PIE_RWX) | \
+ PIRx_ELx_PERM(pte_pi_index(_PAGE_KERNEL_RO), PIE_R) | \
+ PIRx_ELx_PERM(pte_pi_index(_PAGE_KERNEL), PIE_RW))
+
#endif /* __ASM_PGTABLE_PROT_H */
diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h
index 0c07b03d511f..b5943f113af1 100644
--- a/arch/arm64/include/asm/sysreg.h
+++ b/arch/arm64/include/asm/sysreg.h
@@ -704,6 +704,25 @@
#define ICH_VTR_TDS_SHIFT 19
#define ICH_VTR_TDS_MASK (1 << ICH_VTR_TDS_SHIFT)
+/*
+ * Permission Indirection Extension (PIE) permission encodings.
+ * Encodings with the _O suffix, have overlays applied (Permission Overlay Extension).
+ */
+#define PIE_NONE_O 0x0
+#define PIE_R_O 0x1
+#define PIE_X_O 0x2
+#define PIE_RX_O 0x3
+#define PIE_RW_O 0x5
+#define PIE_RWnX_O 0x6
+#define PIE_RWX_O 0x7
+#define PIE_R 0x8
+#define PIE_GCS 0x9
+#define PIE_RX 0xa
+#define PIE_RW 0xc
+#define PIE_RWX 0xe
+
+#define PIRx_ELx_PERM(idx, perm) ((perm) << ((idx) * 4))
+
#define ARM64_FEATURE_FIELD_BITS 4
/* Defined for compatibility only, do not add new users. */