* [RFC PATCH 04/25] powerpc/book3s64/pkeys: Use execute_pkey_disable static key
From: Aneesh Kumar K.V @ 2020-04-27 8:04 UTC (permalink / raw)
To: linuxppc-dev, mpe; +Cc: Aneesh Kumar K.V, linuxram, npiggin
In-Reply-To: <20200427080507.1626327-1-aneesh.kumar@linux.ibm.com>
Use execute_pkey_disabled static key to check for execute key support instead
of pkey_disabled.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
---
arch/powerpc/include/asm/pkeys.h | 10 +---------
arch/powerpc/mm/book3s64/pkeys.c | 5 ++++-
2 files changed, 5 insertions(+), 10 deletions(-)
diff --git a/arch/powerpc/include/asm/pkeys.h b/arch/powerpc/include/asm/pkeys.h
index 47c81d41ea9a..09fbaa409ac4 100644
--- a/arch/powerpc/include/asm/pkeys.h
+++ b/arch/powerpc/include/asm/pkeys.h
@@ -126,15 +126,7 @@ static inline int mm_pkey_free(struct mm_struct *mm, int pkey)
* Try to dedicate one of the protection keys to be used as an
* execute-only protection key.
*/
-extern int __execute_only_pkey(struct mm_struct *mm);
-static inline int execute_only_pkey(struct mm_struct *mm)
-{
- if (static_branch_likely(&pkey_disabled))
- return -1;
-
- return __execute_only_pkey(mm);
-}
-
+extern int execute_only_pkey(struct mm_struct *mm);
extern int __arch_override_mprotect_pkey(struct vm_area_struct *vma,
int prot, int pkey);
static inline int arch_override_mprotect_pkey(struct vm_area_struct *vma,
diff --git a/arch/powerpc/mm/book3s64/pkeys.c b/arch/powerpc/mm/book3s64/pkeys.c
index 36cc4ff8ea5b..e0e63640b227 100644
--- a/arch/powerpc/mm/book3s64/pkeys.c
+++ b/arch/powerpc/mm/book3s64/pkeys.c
@@ -345,8 +345,11 @@ void thread_pkey_regs_init(struct thread_struct *thread)
write_uamor(default_uamor);
}
-int __execute_only_pkey(struct mm_struct *mm)
+int execute_only_pkey(struct mm_struct *mm)
{
+ if (static_branch_likely(&execute_pkey_disabled))
+ return -1;
+
return mm->context.execute_only_pkey;
}
--
2.25.3
^ permalink raw reply related
* [RFC PATCH 05/25] powerpc/book3s64/pkeys: Use MMU_FTR_PKEY instead of pkey_disabled static key
From: Aneesh Kumar K.V @ 2020-04-27 8:04 UTC (permalink / raw)
To: linuxppc-dev, mpe; +Cc: Aneesh Kumar K.V, linuxram, npiggin
In-Reply-To: <20200427080507.1626327-1-aneesh.kumar@linux.ibm.com>
Instead of pkey_disabled static key use mmu feature MMU_FTR_PKEY.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
---
arch/powerpc/include/asm/book3s/64/pkeys.h | 2 +-
arch/powerpc/include/asm/pkeys.h | 14 ++++++--------
arch/powerpc/mm/book3s64/pkeys.c | 16 +++++++---------
3 files changed, 14 insertions(+), 18 deletions(-)
diff --git a/arch/powerpc/include/asm/book3s/64/pkeys.h b/arch/powerpc/include/asm/book3s/64/pkeys.h
index c2c7d744e3bb..e591bebb1a6d 100644
--- a/arch/powerpc/include/asm/book3s/64/pkeys.h
+++ b/arch/powerpc/include/asm/book3s/64/pkeys.h
@@ -7,7 +7,7 @@
static inline u64 vmflag_to_pte_pkey_bits(u64 vm_flags)
{
- if (static_branch_likely(&pkey_disabled))
+ if (!mmu_has_feature(MMU_FTR_PKEY))
return 0x0UL;
if (radix_enabled())
diff --git a/arch/powerpc/include/asm/pkeys.h b/arch/powerpc/include/asm/pkeys.h
index 09fbaa409ac4..b1d448c53209 100644
--- a/arch/powerpc/include/asm/pkeys.h
+++ b/arch/powerpc/include/asm/pkeys.h
@@ -11,7 +11,6 @@
#include <linux/jump_label.h>
#include <asm/firmware.h>
-DECLARE_STATIC_KEY_FALSE(pkey_disabled);
extern int max_pkey;
extern u32 reserved_allocation_mask; /* bits set for reserved keys */
@@ -38,7 +37,7 @@ static inline u64 pkey_to_vmflag_bits(u16 pkey)
static inline int vma_pkey(struct vm_area_struct *vma)
{
- if (static_branch_likely(&pkey_disabled))
+ if (!mmu_has_feature(MMU_FTR_PKEY))
return 0;
return (vma->vm_flags & ARCH_VM_PKEY_FLAGS) >> VM_PKEY_SHIFT;
}
@@ -93,9 +92,8 @@ static inline int mm_pkey_alloc(struct mm_struct *mm)
u32 all_pkeys_mask = (u32)(~(0x0));
int ret;
- if (static_branch_likely(&pkey_disabled))
+ if (!mmu_has_feature(MMU_FTR_PKEY))
return -1;
-
/*
* Are we out of pkeys? We must handle this specially because ffz()
* behavior is undefined if there are no zeros.
@@ -111,7 +109,7 @@ static inline int mm_pkey_alloc(struct mm_struct *mm)
static inline int mm_pkey_free(struct mm_struct *mm, int pkey)
{
- if (static_branch_likely(&pkey_disabled))
+ if (!mmu_has_feature(MMU_FTR_PKEY))
return -1;
if (!mm_pkey_is_allocated(mm, pkey))
@@ -132,7 +130,7 @@ extern int __arch_override_mprotect_pkey(struct vm_area_struct *vma,
static inline int arch_override_mprotect_pkey(struct vm_area_struct *vma,
int prot, int pkey)
{
- if (static_branch_likely(&pkey_disabled))
+ if (!mmu_has_feature(MMU_FTR_PKEY))
return 0;
/*
@@ -150,7 +148,7 @@ extern int __arch_set_user_pkey_access(struct task_struct *tsk, int pkey,
static inline int arch_set_user_pkey_access(struct task_struct *tsk, int pkey,
unsigned long init_val)
{
- if (static_branch_likely(&pkey_disabled))
+ if (!mmu_has_feature(MMU_FTR_PKEY))
return -EINVAL;
/*
@@ -167,7 +165,7 @@ static inline int arch_set_user_pkey_access(struct task_struct *tsk, int pkey,
static inline bool arch_pkeys_enabled(void)
{
- return !static_branch_likely(&pkey_disabled);
+ return mmu_has_feature(MMU_FTR_PKEY);
}
extern void pkey_mm_init(struct mm_struct *mm);
diff --git a/arch/powerpc/mm/book3s64/pkeys.c b/arch/powerpc/mm/book3s64/pkeys.c
index e0e63640b227..8a589509d6fc 100644
--- a/arch/powerpc/mm/book3s64/pkeys.c
+++ b/arch/powerpc/mm/book3s64/pkeys.c
@@ -13,7 +13,6 @@
#include <linux/of_fdt.h>
-DEFINE_STATIC_KEY_FALSE(pkey_disabled);
DEFINE_STATIC_KEY_FALSE(execute_pkey_disabled);
int max_pkey; /* Maximum key value supported */
/*
@@ -114,7 +113,6 @@ void __init pkey_early_init_devtree(void)
pkeys_total = scan_pkey_feature();
if (!pkeys_total) {
/* No support for pkey. Mark it disabled */
- static_branch_enable(&pkey_disabled);
return;
}
@@ -202,7 +200,7 @@ void __init pkey_early_init_devtree(void)
void pkey_mm_init(struct mm_struct *mm)
{
- if (static_branch_likely(&pkey_disabled))
+ if (!mmu_has_feature(MMU_FTR_PKEY))
return;
mm_pkey_allocation_map(mm) = initial_allocation_mask;
mm->context.execute_only_pkey = execute_only_key;
@@ -306,7 +304,7 @@ int __arch_set_user_pkey_access(struct task_struct *tsk, int pkey,
void thread_pkey_regs_save(struct thread_struct *thread)
{
- if (static_branch_likely(&pkey_disabled))
+ if (!mmu_has_feature(MMU_FTR_PKEY))
return;
/*
@@ -320,7 +318,7 @@ void thread_pkey_regs_save(struct thread_struct *thread)
void thread_pkey_regs_restore(struct thread_struct *new_thread,
struct thread_struct *old_thread)
{
- if (static_branch_likely(&pkey_disabled))
+ if (!mmu_has_feature(MMU_FTR_PKEY))
return;
if (old_thread->amr != new_thread->amr)
@@ -333,7 +331,7 @@ void thread_pkey_regs_restore(struct thread_struct *new_thread,
void thread_pkey_regs_init(struct thread_struct *thread)
{
- if (static_branch_likely(&pkey_disabled))
+ if (!mmu_has_feature(MMU_FTR_PKEY))
return;
thread->amr = default_amr;
@@ -408,7 +406,7 @@ static bool pkey_access_permitted(int pkey, bool write, bool execute)
bool arch_pte_access_permitted(u64 pte, bool write, bool execute)
{
- if (static_branch_likely(&pkey_disabled))
+ if (!mmu_has_feature(MMU_FTR_PKEY))
return true;
return pkey_access_permitted(pte_to_pkey_bits(pte), write, execute);
@@ -425,7 +423,7 @@ bool arch_pte_access_permitted(u64 pte, bool write, bool execute)
bool arch_vma_access_permitted(struct vm_area_struct *vma, bool write,
bool execute, bool foreign)
{
- if (static_branch_likely(&pkey_disabled))
+ if (!mmu_has_feature(MMU_FTR_PKEY))
return true;
/*
* Do not enforce our key-permissions on a foreign vma.
@@ -438,7 +436,7 @@ bool arch_vma_access_permitted(struct vm_area_struct *vma, bool write,
void arch_dup_pkeys(struct mm_struct *oldmm, struct mm_struct *mm)
{
- if (static_branch_likely(&pkey_disabled))
+ if (!mmu_has_feature(MMU_FTR_PKEY))
return;
/* Duplicate the oldmm pkey state in mm: */
--
2.25.3
^ permalink raw reply related
* [RFC PATCH 06/25] powerpc/book3s64/kuap: Move KUAP related function outside radix
From: Aneesh Kumar K.V @ 2020-04-27 8:04 UTC (permalink / raw)
To: linuxppc-dev, mpe; +Cc: Aneesh Kumar K.V, linuxram, npiggin
In-Reply-To: <20200427080507.1626327-1-aneesh.kumar@linux.ibm.com>
The next set of patches adds support for kuap with hash translation.
In preparation for that rename/move kuap related functions to
non radix names.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
---
.../asm/book3s/64/{kup-radix.h => kup.h} | 6 +++---
arch/powerpc/include/asm/kup.h | 2 +-
arch/powerpc/kernel/syscall_64.c | 2 +-
arch/powerpc/mm/book3s64/pkeys.c | 18 ++++++++++++++++++
arch/powerpc/mm/book3s64/radix_pgtable.c | 18 ------------------
5 files changed, 23 insertions(+), 23 deletions(-)
rename arch/powerpc/include/asm/book3s/64/{kup-radix.h => kup.h} (96%)
diff --git a/arch/powerpc/include/asm/book3s/64/kup-radix.h b/arch/powerpc/include/asm/book3s/64/kup.h
similarity index 96%
rename from arch/powerpc/include/asm/book3s/64/kup-radix.h
rename to arch/powerpc/include/asm/book3s/64/kup.h
index 224658efe2fd..8d76044a971f 100644
--- a/arch/powerpc/include/asm/book3s/64/kup-radix.h
+++ b/arch/powerpc/include/asm/book3s/64/kup.h
@@ -1,6 +1,6 @@
/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _ASM_POWERPC_BOOK3S_64_KUP_RADIX_H
-#define _ASM_POWERPC_BOOK3S_64_KUP_RADIX_H
+#ifndef _ASM_POWERPC_BOOK3S_64_KUP_H
+#define _ASM_POWERPC_BOOK3S_64_KUP_H
#include <linux/const.h>
#include <asm/reg.h>
@@ -160,4 +160,4 @@ static inline void kuap_check_amr(void)
#endif /* __ASSEMBLY__ */
-#endif /* _ASM_POWERPC_BOOK3S_64_KUP_RADIX_H */
+#endif /* _ASM_POWERPC_BOOK3S_64_KUP_H */
diff --git a/arch/powerpc/include/asm/kup.h b/arch/powerpc/include/asm/kup.h
index 92bcd1a26d73..248438dff74a 100644
--- a/arch/powerpc/include/asm/kup.h
+++ b/arch/powerpc/include/asm/kup.h
@@ -13,7 +13,7 @@
#define KUAP_CURRENT 4
#ifdef CONFIG_PPC64
-#include <asm/book3s/64/kup-radix.h>
+#include <asm/book3s/64/kup.h>
#endif
#ifdef CONFIG_PPC_8xx
#include <asm/nohash/32/kup-8xx.h>
diff --git a/arch/powerpc/kernel/syscall_64.c b/arch/powerpc/kernel/syscall_64.c
index 0625c251548b..09695e042363 100644
--- a/arch/powerpc/kernel/syscall_64.c
+++ b/arch/powerpc/kernel/syscall_64.c
@@ -2,7 +2,7 @@
#include <linux/err.h>
#include <asm/asm-prototypes.h>
-#include <asm/book3s/64/kup-radix.h>
+#include <asm/book3s/64/kup.h>
#include <asm/cputime.h>
#include <asm/hw_irq.h>
#include <asm/kprobes.h>
diff --git a/arch/powerpc/mm/book3s64/pkeys.c b/arch/powerpc/mm/book3s64/pkeys.c
index 8a589509d6fc..efb65629d05b 100644
--- a/arch/powerpc/mm/book3s64/pkeys.c
+++ b/arch/powerpc/mm/book3s64/pkeys.c
@@ -198,6 +198,24 @@ void __init pkey_early_init_devtree(void)
return;
}
+#ifdef CONFIG_PPC_KUAP
+void setup_kuap(bool disabled)
+{
+ if (disabled || !early_radix_enabled())
+ return;
+
+ if (smp_processor_id() == boot_cpuid) {
+ pr_info("Activating Kernel Userspace Access Prevention\n");
+ cur_cpu_spec->mmu_features |= MMU_FTR_RADIX_KUAP;
+ }
+
+ /* Make sure userspace can't change the AMR */
+ mtspr(SPRN_UAMOR, 0);
+ mtspr(SPRN_AMR, AMR_KUAP_BLOCKED);
+ isync();
+}
+#endif
+
void pkey_mm_init(struct mm_struct *mm)
{
if (!mmu_has_feature(MMU_FTR_PKEY))
diff --git a/arch/powerpc/mm/book3s64/radix_pgtable.c b/arch/powerpc/mm/book3s64/radix_pgtable.c
index 8f9edf07063a..74558ce6b5cb 100644
--- a/arch/powerpc/mm/book3s64/radix_pgtable.c
+++ b/arch/powerpc/mm/book3s64/radix_pgtable.c
@@ -526,24 +526,6 @@ void setup_kuep(bool disabled)
}
#endif
-#ifdef CONFIG_PPC_KUAP
-void setup_kuap(bool disabled)
-{
- if (disabled || !early_radix_enabled())
- return;
-
- if (smp_processor_id() == boot_cpuid) {
- pr_info("Activating Kernel Userspace Access Prevention\n");
- cur_cpu_spec->mmu_features |= MMU_FTR_RADIX_KUAP;
- }
-
- /* Make sure userspace can't change the AMR */
- mtspr(SPRN_UAMOR, 0);
- mtspr(SPRN_AMR, AMR_KUAP_BLOCKED);
- isync();
-}
-#endif
-
void __init radix__early_init_mmu(void)
{
unsigned long lpcr;
--
2.25.3
^ permalink raw reply related
* [RFC PATCH 07/25] powerpc/book3s64/kuep: Move KUEP related function outside radix
From: Aneesh Kumar K.V @ 2020-04-27 8:04 UTC (permalink / raw)
To: linuxppc-dev, mpe; +Cc: Aneesh Kumar K.V, linuxram, npiggin
In-Reply-To: <20200427080507.1626327-1-aneesh.kumar@linux.ibm.com>
The next set of patches adds support for kuep with hash translation.
In preparation for that rename/move kuap related functions to
non radix names.
Also set MMU_FTR_KUEP and add the missing isync().
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
---
arch/powerpc/include/asm/book3s/64/kup.h | 1 +
arch/powerpc/mm/book3s64/pkeys.c | 21 +++++++++++++++++++++
arch/powerpc/mm/book3s64/radix_pgtable.c | 18 ------------------
3 files changed, 22 insertions(+), 18 deletions(-)
diff --git a/arch/powerpc/include/asm/book3s/64/kup.h b/arch/powerpc/include/asm/book3s/64/kup.h
index 8d76044a971f..047f4298c053 100644
--- a/arch/powerpc/include/asm/book3s/64/kup.h
+++ b/arch/powerpc/include/asm/book3s/64/kup.h
@@ -7,6 +7,7 @@
#define AMR_KUAP_BLOCK_READ UL(0x4000000000000000)
#define AMR_KUAP_BLOCK_WRITE UL(0x8000000000000000)
+#define AMR_KUEP_BLOCKED (1UL << 62)
#define AMR_KUAP_BLOCKED (AMR_KUAP_BLOCK_READ | AMR_KUAP_BLOCK_WRITE)
#define AMR_KUAP_SHIFT 62
diff --git a/arch/powerpc/mm/book3s64/pkeys.c b/arch/powerpc/mm/book3s64/pkeys.c
index efb65629d05b..dc6b56c6e004 100644
--- a/arch/powerpc/mm/book3s64/pkeys.c
+++ b/arch/powerpc/mm/book3s64/pkeys.c
@@ -198,6 +198,27 @@ void __init pkey_early_init_devtree(void)
return;
}
+#ifdef CONFIG_PPC_KUEP
+void setup_kuep(bool disabled)
+{
+ if (disabled || !early_radix_enabled())
+ return;
+
+ if (smp_processor_id() == boot_cpuid) {
+ pr_info("Activating Kernel Userspace Execution Prevention\n");
+ cur_cpu_spec->mmu_features |= MMU_FTR_KUEP;
+ }
+
+ /*
+ * Radix always uses key0 of the IAMR to determine if an access is
+ * allowed. We set bit 0 (IBM bit 1) of key0, to prevent instruction
+ * fetch.
+ */
+ mtspr(SPRN_IAMR, AMR_KUEP_BLOCKED);
+ isync();
+}
+#endif
+
#ifdef CONFIG_PPC_KUAP
void setup_kuap(bool disabled)
{
diff --git a/arch/powerpc/mm/book3s64/radix_pgtable.c b/arch/powerpc/mm/book3s64/radix_pgtable.c
index 74558ce6b5cb..3fb088eecece 100644
--- a/arch/powerpc/mm/book3s64/radix_pgtable.c
+++ b/arch/powerpc/mm/book3s64/radix_pgtable.c
@@ -508,24 +508,6 @@ static void radix_init_amor(void)
mtspr(SPRN_AMOR, (3ul << 62));
}
-#ifdef CONFIG_PPC_KUEP
-void setup_kuep(bool disabled)
-{
- if (disabled || !early_radix_enabled())
- return;
-
- if (smp_processor_id() == boot_cpuid)
- pr_info("Activating Kernel Userspace Execution Prevention\n");
-
- /*
- * Radix always uses key0 of the IAMR to determine if an access is
- * allowed. We set bit 0 (IBM bit 1) of key0, to prevent instruction
- * fetch.
- */
- mtspr(SPRN_IAMR, (1ul << 62));
-}
-#endif
-
void __init radix__early_init_mmu(void)
{
unsigned long lpcr;
--
2.25.3
^ permalink raw reply related
* [RFC PATCH 09/25] powerpc/book3s64/kuap/kuep: Make KUAP and KUEP a subfeature of PPC_MEM_KEYS
From: Aneesh Kumar K.V @ 2020-04-27 8:04 UTC (permalink / raw)
To: linuxppc-dev, mpe; +Cc: Aneesh Kumar K.V, linuxram, npiggin
In-Reply-To: <20200427080507.1626327-1-aneesh.kumar@linux.ibm.com>
The next set of patches adds support for kuap with hash translation.
Hence make KUAP a BOOK3S_64 feature. Also make it a subfeature of
PPC_MEM_KEYS. Hash translation is going to use pkeys to support
KUAP/KUEP. Adding this dependency reduces the code complexity and
enables us to move some of the initialization code to pkeys.c
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
---
arch/powerpc/platforms/Kconfig.cputype | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/powerpc/platforms/Kconfig.cputype b/arch/powerpc/platforms/Kconfig.cputype
index 0c3c1902135c..8100d5c0812d 100644
--- a/arch/powerpc/platforms/Kconfig.cputype
+++ b/arch/powerpc/platforms/Kconfig.cputype
@@ -99,6 +99,8 @@ config PPC_BOOK3S_64
select ARCH_SUPPORTS_NUMA_BALANCING
select IRQ_WORK
select PPC_MM_SLICES
+ select PPC_HAVE_KUAP if PPC_MEM_KEYS
+ select PPC_HAVE_KUEP if PPC_MEM_KEYS
config PPC_BOOK3E_64
bool "Embedded processors"
@@ -350,8 +352,6 @@ config PPC_RADIX_MMU
bool "Radix MMU Support"
depends on PPC_BOOK3S_64
select ARCH_HAS_GIGANTIC_PAGE
- select PPC_HAVE_KUEP
- select PPC_HAVE_KUAP
default y
help
Enable support for the Power ISA 3.0 Radix style MMU. Currently this
--
2.25.3
^ permalink raw reply related
* [RFC PATCH 08/25] powerpc/book3s64/kuap: Rename MMU_FTR_RADIX_KUAP to MMU_FTR_KUAP
From: Aneesh Kumar K.V @ 2020-04-27 8:04 UTC (permalink / raw)
To: linuxppc-dev, mpe; +Cc: Aneesh Kumar K.V, linuxram, npiggin
In-Reply-To: <20200427080507.1626327-1-aneesh.kumar@linux.ibm.com>
The next set of patches adds support for kuap with hash translation.
In preparation for that rename/move kuap related functions to
non radix names.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
---
arch/powerpc/include/asm/book3s/64/kup.h | 16 ++++++++--------
arch/powerpc/include/asm/mmu.h | 6 +++---
arch/powerpc/kernel/syscall_64.c | 4 ++--
arch/powerpc/mm/book3s64/pkeys.c | 2 +-
4 files changed, 14 insertions(+), 14 deletions(-)
diff --git a/arch/powerpc/include/asm/book3s/64/kup.h b/arch/powerpc/include/asm/book3s/64/kup.h
index 047f4298c053..c56894b9b3a1 100644
--- a/arch/powerpc/include/asm/book3s/64/kup.h
+++ b/arch/powerpc/include/asm/book3s/64/kup.h
@@ -19,7 +19,7 @@
ld \gpr, STACK_REGS_KUAP(r1)
isync
mtspr SPRN_AMR, \gpr
- END_MMU_FTR_SECTION_NESTED_IFSET(MMU_FTR_RADIX_KUAP, 67)
+ END_MMU_FTR_SECTION_NESTED_IFSET(MMU_FTR_KUAP, 67)
#endif
.endm
@@ -31,7 +31,7 @@
sldi \gpr2, \gpr2, AMR_KUAP_SHIFT
999: tdne \gpr1, \gpr2
EMIT_BUG_ENTRY 999b, __FILE__, __LINE__, (BUGFLAG_WARNING | BUGFLAG_ONCE)
- END_MMU_FTR_SECTION_NESTED_IFSET(MMU_FTR_RADIX_KUAP, 67)
+ END_MMU_FTR_SECTION_NESTED_IFSET(MMU_FTR_KUAP, 67)
#endif
.endm
@@ -51,7 +51,7 @@
mtspr SPRN_AMR, \gpr2
isync
99:
- END_MMU_FTR_SECTION_NESTED_IFSET(MMU_FTR_RADIX_KUAP, 67)
+ END_MMU_FTR_SECTION_NESTED_IFSET(MMU_FTR_KUAP, 67)
#endif
.endm
@@ -64,7 +64,7 @@
static inline void kuap_restore_amr(struct pt_regs *regs)
{
- if (mmu_has_feature(MMU_FTR_RADIX_KUAP)) {
+ if (mmu_has_feature(MMU_FTR_KUAP)) {
isync();
mtspr(SPRN_AMR, regs->kuap);
/*
@@ -76,7 +76,7 @@ static inline void kuap_restore_amr(struct pt_regs *regs)
static inline void kuap_check_amr(void)
{
- if (IS_ENABLED(CONFIG_PPC_KUAP_DEBUG) && mmu_has_feature(MMU_FTR_RADIX_KUAP))
+ if (IS_ENABLED(CONFIG_PPC_KUAP_DEBUG) && mmu_has_feature(MMU_FTR_KUAP))
WARN_ON_ONCE(mfspr(SPRN_AMR) != AMR_KUAP_BLOCKED);
}
@@ -87,7 +87,7 @@ static inline void kuap_check_amr(void)
static inline unsigned long get_kuap(void)
{
- if (!early_mmu_has_feature(MMU_FTR_RADIX_KUAP))
+ if (!early_mmu_has_feature(MMU_FTR_KUAP))
return 0;
return mfspr(SPRN_AMR);
@@ -95,7 +95,7 @@ static inline unsigned long get_kuap(void)
static inline void set_kuap(unsigned long value)
{
- if (!early_mmu_has_feature(MMU_FTR_RADIX_KUAP))
+ if (!early_mmu_has_feature(MMU_FTR_KUAP))
return;
/*
@@ -145,7 +145,7 @@ static inline void restore_user_access(unsigned long flags)
static inline bool
bad_kuap_fault(struct pt_regs *regs, unsigned long address, bool is_write)
{
- return WARN(mmu_has_feature(MMU_FTR_RADIX_KUAP) &&
+ return WARN(mmu_has_feature(MMU_FTR_KUAP) &&
(regs->kuap & (is_write ? AMR_KUAP_BLOCK_WRITE : AMR_KUAP_BLOCK_READ)),
"Bug: %s fault blocked by AMR!", is_write ? "Write" : "Read");
}
diff --git a/arch/powerpc/include/asm/mmu.h b/arch/powerpc/include/asm/mmu.h
index f6fcc9daf6ac..55b746d6b844 100644
--- a/arch/powerpc/include/asm/mmu.h
+++ b/arch/powerpc/include/asm/mmu.h
@@ -112,7 +112,7 @@
/*
* Supports KUAP (key 0 controlling userspace addresses) on radix
*/
-#define MMU_FTR_RADIX_KUAP ASM_CONST(0x80000000)
+#define MMU_FTR_KUAP ASM_CONST(0x80000000)
/* MMU feature bit sets for various CPUs */
#define MMU_FTRS_DEFAULT_HPTE_ARCH_V2 \
@@ -174,10 +174,10 @@ enum {
#endif
#ifdef CONFIG_PPC_RADIX_MMU
MMU_FTR_TYPE_RADIX |
+#endif /* CONFIG_PPC_RADIX_MMU */
#ifdef CONFIG_PPC_KUAP
- MMU_FTR_RADIX_KUAP |
+ MMU_FTR_KUAP |
#endif /* CONFIG_PPC_KUAP */
-#endif /* CONFIG_PPC_RADIX_MMU */
#ifdef CONFIG_PPC_MEM_KEYS
MMU_FTR_PKEY |
#endif
diff --git a/arch/powerpc/kernel/syscall_64.c b/arch/powerpc/kernel/syscall_64.c
index 09695e042363..c0fdb02a13d5 100644
--- a/arch/powerpc/kernel/syscall_64.c
+++ b/arch/powerpc/kernel/syscall_64.c
@@ -314,7 +314,7 @@ notrace unsigned long interrupt_exit_kernel_prepare(struct pt_regs *regs, unsign
BUG_ON(regs->msr & MSR_PR);
BUG_ON(!FULL_REGS(regs));
- if (mmu_has_feature(MMU_FTR_RADIX_KUAP)) {
+ if (mmu_has_feature(MMU_FTR_KUAP)) {
amr = mfspr(SPRN_AMR);
if (IS_ENABLED(CONFIG_PPC_KUAP_DEBUG)) /* kuap_check_amr() */
WARN_ON_ONCE(amr != AMR_KUAP_BLOCKED);
@@ -377,7 +377,7 @@ notrace unsigned long interrupt_exit_kernel_prepare(struct pt_regs *regs, unsign
* We don't need to restore AMR on the way back to userspace for KUAP.
* The value of AMR only matters while we're in the kernel.
*/
- if (mmu_has_feature(MMU_FTR_RADIX_KUAP) && (regs->kuap != amr)) {
+ if (mmu_has_feature(MMU_FTR_KUAP) && (regs->kuap != amr)) {
isync();
mtspr(SPRN_AMR, regs->kuap);
}
diff --git a/arch/powerpc/mm/book3s64/pkeys.c b/arch/powerpc/mm/book3s64/pkeys.c
index dc6b56c6e004..727284607fa8 100644
--- a/arch/powerpc/mm/book3s64/pkeys.c
+++ b/arch/powerpc/mm/book3s64/pkeys.c
@@ -227,7 +227,7 @@ void setup_kuap(bool disabled)
if (smp_processor_id() == boot_cpuid) {
pr_info("Activating Kernel Userspace Access Prevention\n");
- cur_cpu_spec->mmu_features |= MMU_FTR_RADIX_KUAP;
+ cur_cpu_spec->mmu_features |= MMU_FTR_KUAP;
}
/* Make sure userspace can't change the AMR */
--
2.25.3
^ permalink raw reply related
* [RFC PATCH 10/25] powerpc/book3s64/kuap: Move UAMOR setup to key init function
From: Aneesh Kumar K.V @ 2020-04-27 8:04 UTC (permalink / raw)
To: linuxppc-dev, mpe; +Cc: Aneesh Kumar K.V, linuxram, npiggin
In-Reply-To: <20200427080507.1626327-1-aneesh.kumar@linux.ibm.com>
With hash translation, the kernel will use key 3 for implementing
KUAP feature. Hence the default UAMOR value depends on what other
keys are marked reserved. Move the UAMOR initialization to pkeys init.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
---
arch/powerpc/include/asm/pkeys.h | 1 +
arch/powerpc/kernel/smp.c | 3 +++
arch/powerpc/mm/book3s64/pkeys.c | 25 ++++++++++++++++++++-----
3 files changed, 24 insertions(+), 5 deletions(-)
diff --git a/arch/powerpc/include/asm/pkeys.h b/arch/powerpc/include/asm/pkeys.h
index b1d448c53209..6e8157f78b52 100644
--- a/arch/powerpc/include/asm/pkeys.h
+++ b/arch/powerpc/include/asm/pkeys.h
@@ -12,6 +12,7 @@
#include <asm/firmware.h>
extern int max_pkey;
+extern u64 default_uamor;
extern u32 reserved_allocation_mask; /* bits set for reserved keys */
#define ARCH_VM_PKEY_FLAGS (VM_PKEY_BIT0 | VM_PKEY_BIT1 | VM_PKEY_BIT2 | \
diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c
index 6d2a3a3666f0..5d1e5489bcd2 100644
--- a/arch/powerpc/kernel/smp.c
+++ b/arch/powerpc/kernel/smp.c
@@ -59,6 +59,7 @@
#include <asm/asm-prototypes.h>
#include <asm/cpu_has_feature.h>
#include <asm/ftrace.h>
+#include <asm/pkeys.h>
#ifdef DEBUG
#include <asm/udbg.h>
@@ -1256,6 +1257,8 @@ void start_secondary(void *unused)
mmgrab(&init_mm);
current->active_mm = &init_mm;
+ mtspr(SPRN_UAMOR, default_uamor);
+
smp_store_cpu_info(cpu);
set_dec(tb_ticks_per_jiffy);
preempt_disable();
diff --git a/arch/powerpc/mm/book3s64/pkeys.c b/arch/powerpc/mm/book3s64/pkeys.c
index 727284607fa8..a0406ea32487 100644
--- a/arch/powerpc/mm/book3s64/pkeys.c
+++ b/arch/powerpc/mm/book3s64/pkeys.c
@@ -23,7 +23,7 @@ static u32 initial_allocation_mask; /* Bits set for the initially allocated k
static u64 default_amr;
static u64 default_iamr;
/* Allow all keys to be modified by default */
-static u64 default_uamor = ~0x0UL;
+u64 default_uamor = ~0x0UL;
/*
* Key used to implement PROT_EXEC mmap. Denies READ/WRITE
* We pick key 2 because 0 is special key and 1 is reserved as per ISA.
@@ -112,8 +112,16 @@ void __init pkey_early_init_devtree(void)
/* scan the device tree for pkey feature */
pkeys_total = scan_pkey_feature();
if (!pkeys_total) {
- /* No support for pkey. Mark it disabled */
- return;
+ /*
+ * No key support but on radix we can use key 0
+ * to implement kuap.
+ */
+ if (early_radix_enabled())
+ /*
+ * Make sure userspace can't change the AMR
+ */
+ default_uamor = 0;
+ goto err_out;
}
cur_cpu_spec->mmu_features |= MMU_FTR_PKEY;
@@ -195,6 +203,12 @@ void __init pkey_early_init_devtree(void)
*/
initial_allocation_mask |= reserved_allocation_mask;
+err_out:
+ /*
+ * Setup uamor on boot cpu
+ */
+ mtspr(SPRN_UAMOR, default_uamor);
+
return;
}
@@ -230,8 +244,9 @@ void setup_kuap(bool disabled)
cur_cpu_spec->mmu_features |= MMU_FTR_KUAP;
}
- /* Make sure userspace can't change the AMR */
- mtspr(SPRN_UAMOR, 0);
+ /*
+ * Set the default kernel AMR values on all cpus.
+ */
mtspr(SPRN_AMR, AMR_KUAP_BLOCKED);
isync();
}
--
2.25.3
^ permalink raw reply related
* [RFC PATCH 11/25] powerpc/book3s64/kuap: Use Key 3 for kernel mapping with hash translation
From: Aneesh Kumar K.V @ 2020-04-27 8:04 UTC (permalink / raw)
To: linuxppc-dev, mpe; +Cc: Aneesh Kumar K.V, linuxram, npiggin
In-Reply-To: <20200427080507.1626327-1-aneesh.kumar@linux.ibm.com>
This patch updates kernel hash page table entries to use storage key 3
for its mapping. This implies all kernel access will now use key 3 to
control READ/WRITE. The patch also prevents the allocation of key 3 from
userspace and UAMOR value is updated such that userspace cannot modify key 3.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
---
.../powerpc/include/asm/book3s/64/hash-pkey.h | 24 ++++++++++++++-----
arch/powerpc/include/asm/book3s/64/hash.h | 3 ++-
arch/powerpc/include/asm/book3s/64/mmu-hash.h | 1 +
arch/powerpc/mm/book3s64/hash_4k.c | 2 +-
arch/powerpc/mm/book3s64/hash_64k.c | 4 ++--
arch/powerpc/mm/book3s64/hash_hugepage.c | 2 +-
arch/powerpc/mm/book3s64/hash_hugetlbpage.c | 2 +-
arch/powerpc/mm/book3s64/hash_pgtable.c | 2 +-
arch/powerpc/mm/book3s64/hash_utils.c | 10 ++++----
arch/powerpc/mm/book3s64/pkeys.c | 4 ++++
10 files changed, 37 insertions(+), 17 deletions(-)
diff --git a/arch/powerpc/include/asm/book3s/64/hash-pkey.h b/arch/powerpc/include/asm/book3s/64/hash-pkey.h
index 795010897e5d..fc75b815c9ca 100644
--- a/arch/powerpc/include/asm/book3s/64/hash-pkey.h
+++ b/arch/powerpc/include/asm/book3s/64/hash-pkey.h
@@ -2,6 +2,9 @@
#ifndef _ASM_POWERPC_BOOK3S_64_HASH_PKEY_H
#define _ASM_POWERPC_BOOK3S_64_HASH_PKEY_H
+/* We use key 3 for KERNEL */
+#define HASH_DEFAULT_KERNEL_KEY (HPTE_R_KEY_BIT0 | HPTE_R_KEY_BIT1)
+
static inline u64 hash__vmflag_to_pte_pkey_bits(u64 vm_flags)
{
return (((vm_flags & VM_PKEY_BIT0) ? H_PTE_PKEY_BIT0 : 0x0UL) |
@@ -11,13 +14,22 @@ static inline u64 hash__vmflag_to_pte_pkey_bits(u64 vm_flags)
((vm_flags & VM_PKEY_BIT4) ? H_PTE_PKEY_BIT4 : 0x0UL));
}
-static inline u64 pte_to_hpte_pkey_bits(u64 pteflags)
+static inline u64 pte_to_hpte_pkey_bits(u64 pteflags, unsigned long flags)
{
- return (((pteflags & H_PTE_PKEY_BIT4) ? HPTE_R_KEY_BIT4 : 0x0UL) |
- ((pteflags & H_PTE_PKEY_BIT3) ? HPTE_R_KEY_BIT3 : 0x0UL) |
- ((pteflags & H_PTE_PKEY_BIT2) ? HPTE_R_KEY_BIT2 : 0x0UL) |
- ((pteflags & H_PTE_PKEY_BIT1) ? HPTE_R_KEY_BIT1 : 0x0UL) |
- ((pteflags & H_PTE_PKEY_BIT0) ? HPTE_R_KEY_BIT0 : 0x0UL));
+ unsigned long pte_pkey;
+
+ pte_pkey = (((pteflags & H_PTE_PKEY_BIT4) ? HPTE_R_KEY_BIT4 : 0x0UL) |
+ ((pteflags & H_PTE_PKEY_BIT3) ? HPTE_R_KEY_BIT3 : 0x0UL) |
+ ((pteflags & H_PTE_PKEY_BIT2) ? HPTE_R_KEY_BIT2 : 0x0UL) |
+ ((pteflags & H_PTE_PKEY_BIT1) ? HPTE_R_KEY_BIT1 : 0x0UL) |
+ ((pteflags & H_PTE_PKEY_BIT0) ? HPTE_R_KEY_BIT0 : 0x0UL));
+
+ if (mmu_has_feature(MMU_FTR_KUAP)) {
+ if ((pte_pkey == 0) && (flags & HPTE_USE_KERNEL_KEY))
+ return HASH_DEFAULT_KERNEL_KEY;
+ }
+
+ return pte_pkey;
}
static inline u16 hash__pte_to_pkey_bits(u64 pteflags)
diff --git a/arch/powerpc/include/asm/book3s/64/hash.h b/arch/powerpc/include/asm/book3s/64/hash.h
index 6fc4520092c7..12b65d3d79aa 100644
--- a/arch/powerpc/include/asm/book3s/64/hash.h
+++ b/arch/powerpc/include/asm/book3s/64/hash.h
@@ -145,7 +145,8 @@ extern void hash__mark_initmem_nx(void);
extern void hpte_need_flush(struct mm_struct *mm, unsigned long addr,
pte_t *ptep, unsigned long pte, int huge);
-extern unsigned long htab_convert_pte_flags(unsigned long pteflags);
+extern unsigned long htab_convert_pte_flags(unsigned long pteflags,
+ unsigned long flags);
/* Atomic PTE updates */
static inline unsigned long hash__pte_update(struct mm_struct *mm,
unsigned long addr,
diff --git a/arch/powerpc/include/asm/book3s/64/mmu-hash.h b/arch/powerpc/include/asm/book3s/64/mmu-hash.h
index 58fcc959f9d5..eb9950043b78 100644
--- a/arch/powerpc/include/asm/book3s/64/mmu-hash.h
+++ b/arch/powerpc/include/asm/book3s/64/mmu-hash.h
@@ -452,6 +452,7 @@ static inline unsigned long hpt_hash(unsigned long vpn,
#define HPTE_LOCAL_UPDATE 0x1
#define HPTE_NOHPTE_UPDATE 0x2
+#define HPTE_USE_KERNEL_KEY 0x4
extern int __hash_page_4K(unsigned long ea, unsigned long access,
unsigned long vsid, pte_t *ptep, unsigned long trap,
diff --git a/arch/powerpc/mm/book3s64/hash_4k.c b/arch/powerpc/mm/book3s64/hash_4k.c
index 22e787123cdf..7de1a8a0c62a 100644
--- a/arch/powerpc/mm/book3s64/hash_4k.c
+++ b/arch/powerpc/mm/book3s64/hash_4k.c
@@ -54,7 +54,7 @@ int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
* PP bits. _PAGE_USER is already PP bit 0x2, so we only
* need to add in 0x1 if it's a read-only user page
*/
- rflags = htab_convert_pte_flags(new_pte);
+ rflags = htab_convert_pte_flags(new_pte, flags);
rpte = __real_pte(__pte(old_pte), ptep, PTRS_PER_PTE);
if (cpu_has_feature(CPU_FTR_NOEXECUTE) &&
diff --git a/arch/powerpc/mm/book3s64/hash_64k.c b/arch/powerpc/mm/book3s64/hash_64k.c
index 7084ce2951e6..998c6817ed47 100644
--- a/arch/powerpc/mm/book3s64/hash_64k.c
+++ b/arch/powerpc/mm/book3s64/hash_64k.c
@@ -72,7 +72,7 @@ int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
* Handle the subpage protection bits
*/
subpg_pte = new_pte & ~subpg_prot;
- rflags = htab_convert_pte_flags(subpg_pte);
+ rflags = htab_convert_pte_flags(subpg_pte, flags);
if (cpu_has_feature(CPU_FTR_NOEXECUTE) &&
!cpu_has_feature(CPU_FTR_COHERENT_ICACHE)) {
@@ -260,7 +260,7 @@ int __hash_page_64K(unsigned long ea, unsigned long access,
new_pte |= _PAGE_DIRTY;
} while (!pte_xchg(ptep, __pte(old_pte), __pte(new_pte)));
- rflags = htab_convert_pte_flags(new_pte);
+ rflags = htab_convert_pte_flags(new_pte, flags);
rpte = __real_pte(__pte(old_pte), ptep, PTRS_PER_PTE);
if (cpu_has_feature(CPU_FTR_NOEXECUTE) &&
diff --git a/arch/powerpc/mm/book3s64/hash_hugepage.c b/arch/powerpc/mm/book3s64/hash_hugepage.c
index 440823797de7..c0fabe6c5a12 100644
--- a/arch/powerpc/mm/book3s64/hash_hugepage.c
+++ b/arch/powerpc/mm/book3s64/hash_hugepage.c
@@ -57,7 +57,7 @@ int __hash_page_thp(unsigned long ea, unsigned long access, unsigned long vsid,
if (!(old_pmd & (H_PAGE_THP_HUGE | _PAGE_DEVMAP)))
return 0;
- rflags = htab_convert_pte_flags(new_pmd);
+ rflags = htab_convert_pte_flags(new_pmd, flags);
#if 0
if (!cpu_has_feature(CPU_FTR_COHERENT_ICACHE)) {
diff --git a/arch/powerpc/mm/book3s64/hash_hugetlbpage.c b/arch/powerpc/mm/book3s64/hash_hugetlbpage.c
index eefa89c6117b..8ce8fc327af4 100644
--- a/arch/powerpc/mm/book3s64/hash_hugetlbpage.c
+++ b/arch/powerpc/mm/book3s64/hash_hugetlbpage.c
@@ -72,7 +72,7 @@ int __hash_page_huge(unsigned long ea, unsigned long access, unsigned long vsid,
if (old_pte & (H_PAGE_THP_HUGE | _PAGE_DEVMAP))
return 0;
- rflags = htab_convert_pte_flags(new_pte);
+ rflags = htab_convert_pte_flags(new_pte, flags);
if (unlikely(mmu_psize == MMU_PAGE_16G))
offset = PTRS_PER_PUD;
else
diff --git a/arch/powerpc/mm/book3s64/hash_pgtable.c b/arch/powerpc/mm/book3s64/hash_pgtable.c
index 64733b9cb20a..6c43aaf1c713 100644
--- a/arch/powerpc/mm/book3s64/hash_pgtable.c
+++ b/arch/powerpc/mm/book3s64/hash_pgtable.c
@@ -454,7 +454,7 @@ void hash__mark_initmem_nx(void)
start = (unsigned long)__init_begin;
end = (unsigned long)__init_end;
- pp = htab_convert_pte_flags(pgprot_val(PAGE_KERNEL));
+ pp = htab_convert_pte_flags(pgprot_val(PAGE_KERNEL), HPTE_USE_KERNEL_KEY);
WARN_ON(!hash__change_memory_range(start, end, pp));
}
diff --git a/arch/powerpc/mm/book3s64/hash_utils.c b/arch/powerpc/mm/book3s64/hash_utils.c
index 8ed2411c3f39..bdd4f1792c76 100644
--- a/arch/powerpc/mm/book3s64/hash_utils.c
+++ b/arch/powerpc/mm/book3s64/hash_utils.c
@@ -183,7 +183,7 @@ static struct mmu_psize_def mmu_psize_defaults_gp[] = {
* - We make sure R is always set and never lost
* - C is _PAGE_DIRTY, and *should* always be set for a writeable mapping
*/
-unsigned long htab_convert_pte_flags(unsigned long pteflags)
+unsigned long htab_convert_pte_flags(unsigned long pteflags, unsigned long flags)
{
unsigned long rflags = 0;
@@ -237,7 +237,7 @@ unsigned long htab_convert_pte_flags(unsigned long pteflags)
*/
rflags |= HPTE_R_M;
- rflags |= pte_to_hpte_pkey_bits(pteflags);
+ rflags |= pte_to_hpte_pkey_bits(pteflags, flags);
return rflags;
}
@@ -252,7 +252,7 @@ int htab_bolt_mapping(unsigned long vstart, unsigned long vend,
shift = mmu_psize_defs[psize].shift;
step = 1 << shift;
- prot = htab_convert_pte_flags(prot);
+ prot = htab_convert_pte_flags(prot, HPTE_USE_KERNEL_KEY);
DBG("htab_bolt_mapping(%lx..%lx -> %lx (%lx,%d,%d)\n",
vstart, vend, pstart, prot, psize, ssize);
@@ -1295,12 +1295,14 @@ int hash_page_mm(struct mm_struct *mm, unsigned long ea,
vsid = get_kernel_vsid(ea, mmu_kernel_ssize);
psize = mmu_vmalloc_psize;
ssize = mmu_kernel_ssize;
+ flags |= HPTE_USE_KERNEL_KEY;
break;
case IO_REGION_ID:
vsid = get_kernel_vsid(ea, mmu_kernel_ssize);
psize = mmu_io_psize;
ssize = mmu_kernel_ssize;
+ flags |= HPTE_USE_KERNEL_KEY;
break;
default:
/*
@@ -1894,7 +1896,7 @@ static void kernel_map_linear_page(unsigned long vaddr, unsigned long lmi)
unsigned long hash;
unsigned long vsid = get_kernel_vsid(vaddr, mmu_kernel_ssize);
unsigned long vpn = hpt_vpn(vaddr, vsid, mmu_kernel_ssize);
- unsigned long mode = htab_convert_pte_flags(pgprot_val(PAGE_KERNEL));
+ unsigned long mode = htab_convert_pte_flags(pgprot_val(PAGE_KERNEL), HPTE_USE_KERNEL_KEY);
long ret;
hash = hpt_hash(vpn, PAGE_SHIFT, mmu_kernel_ssize);
diff --git a/arch/powerpc/mm/book3s64/pkeys.c b/arch/powerpc/mm/book3s64/pkeys.c
index a0406ea32487..d0d781876c20 100644
--- a/arch/powerpc/mm/book3s64/pkeys.c
+++ b/arch/powerpc/mm/book3s64/pkeys.c
@@ -189,6 +189,10 @@ void __init pkey_early_init_devtree(void)
*/
reserved_allocation_mask |= (0x1 << 1);
+ /* handle key 3 which is used by kernel for KAUP */
+ reserved_allocation_mask |= (0x1 << 3);
+ default_uamor &= ~(0x3ul << pkeyshift(3));
+
/*
* Prevent the usage of OS reserved keys. Update UAMOR
* for those keys. Also mark the rest of the bits in the
--
2.25.3
^ permalink raw reply related
* [RFC PATCH 12/25] powerpc/exec: Set thread.regs early during exec
From: Aneesh Kumar K.V @ 2020-04-27 8:04 UTC (permalink / raw)
To: linuxppc-dev, mpe; +Cc: Aneesh Kumar K.V, linuxram, npiggin
In-Reply-To: <20200427080507.1626327-1-aneesh.kumar@linux.ibm.com>
In later patches during exec, we would like to access default regs.kuap to
control access to the user mapping. Having thread.regs set early makes the
code changes simpler.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
---
arch/powerpc/kernel/process.c | 24 ++++++++++++------------
1 file changed, 12 insertions(+), 12 deletions(-)
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index 9c21288f8645..78eedf0b5c30 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -1461,9 +1461,18 @@ void flush_thread(void)
#ifdef CONFIG_PPC_BOOK3S_64
void arch_setup_new_exec(void)
{
- if (radix_enabled())
- return;
- hash__setup_new_exec();
+ if (!radix_enabled())
+ hash__setup_new_exec();
+
+ /*
+ * If we exec out of a kernel thread then thread.regs will not be
+ * set. Do it now.
+ */
+ if (!current->thread.regs) {
+ struct pt_regs *regs = task_stack_page(current) + THREAD_SIZE;
+ current->thread.regs = regs - 1;
+ }
+
}
#endif
@@ -1709,15 +1718,6 @@ void start_thread(struct pt_regs *regs, unsigned long start, unsigned long sp)
#endif
#endif
- /*
- * If we exec out of a kernel thread then thread.regs will not be
- * set. Do it now.
- */
- if (!current->thread.regs) {
- struct pt_regs *regs = task_stack_page(current) + THREAD_SIZE;
- current->thread.regs = regs - 1;
- }
-
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
/*
* Clear any transactional state, we're exec()ing. The cause is
--
2.25.3
^ permalink raw reply related
* [RFC PATCH 13/25] powerpc/book3s64/pkeys: Store/restore userspace AMR correctly on entry and exit from kernel
From: Aneesh Kumar K.V @ 2020-04-27 8:04 UTC (permalink / raw)
To: linuxppc-dev, mpe; +Cc: Aneesh Kumar K.V, linuxram, npiggin
In-Reply-To: <20200427080507.1626327-1-aneesh.kumar@linux.ibm.com>
This prepare kernel to operate with a different value than userspace AMR.
For this, AMR needs to be saved and restored on entry and return from the
kernel.
With KUAP we modify kernel AMR when accessing user address from the kernel
via copy_to/from_user interfaces.
If MMU_FTR_KEY is enabled we always use the key mechanism to implement KUAP
feature. If MMU_FTR_KEY is not supported and if we support MMU_FTR_KUAP
(radix translation on POWER9), we can skip restoring AMR on return
to userspace. Userspace won't be using AMR in that specific config.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
---
arch/powerpc/include/asm/book3s/64/kup.h | 86 ++++++++++++++++++++----
arch/powerpc/kernel/entry_64.S | 4 +-
arch/powerpc/kernel/syscall_64.c | 19 +++++-
3 files changed, 92 insertions(+), 17 deletions(-)
diff --git a/arch/powerpc/include/asm/book3s/64/kup.h b/arch/powerpc/include/asm/book3s/64/kup.h
index c56894b9b3a1..85645d1b7102 100644
--- a/arch/powerpc/include/asm/book3s/64/kup.h
+++ b/arch/powerpc/include/asm/book3s/64/kup.h
@@ -13,13 +13,32 @@
#ifdef __ASSEMBLY__
-.macro kuap_restore_amr gpr
-#ifdef CONFIG_PPC_KUAP
+.macro kuap_restore_amr gpr to_user
+#if defined(CONFIG_PPC_MEM_KEYS) || defined (CONFIG_PPC_KUAP)
BEGIN_MMU_FTR_SECTION_NESTED(67)
+ b 101f // handle_pkey_restore_amr
+ END_MMU_FTR_SECTION_NESTED_IFSET(MMU_FTR_PKEY , 67)
+
+ BEGIN_MMU_FTR_SECTION_NESTED(68)
+ b 99f // handle_kuap_restore_amr
+ MMU_FTR_SECTION_ELSE_NESTED(68)
+ b 100f // skip_restore_amr
+ ALT_MMU_FTR_SECTION_END_NESTED_IFSET(MMU_FTR_KUAP, 68)
+
+99: // handle_kuap_restore_amr
+ /*
+ * No key support, don't bother to restore AMR
+ * when returning to userspace.
+ */
+ .ifnb \to_user
+ b 100f
+ .endif
+101: // handle_pkey_restore_amr
ld \gpr, STACK_REGS_KUAP(r1)
isync
mtspr SPRN_AMR, \gpr
- END_MMU_FTR_SECTION_NESTED_IFSET(MMU_FTR_KUAP, 67)
+ /* No isync here because we will return to a different context */
+100: // skip_restore_amr
#endif
.endm
@@ -35,23 +54,58 @@
#endif
.endm
+/*
+ * MMU_FTR_PKEY and MMU_FTR_KUAP can both be enabled on a platform. We prefer
+ * PKEY over KUAP if both can be enabled on the platform.
+ *
+ * With KUAP only enabled on exception if we are coming from userspace we don't
+ * save the AMR at all, because the expectation is that userspace can't change
+ * the AMR if KUAP feature is enabled.
+ */
.macro kuap_save_amr_and_lock gpr1, gpr2, use_cr, msr_pr_cr
-#ifdef CONFIG_PPC_KUAP
+#if defined(CONFIG_PPC_MEM_KEYS) || defined (CONFIG_PPC_KUAP)
+
BEGIN_MMU_FTR_SECTION_NESTED(67)
+ b 101f // handle_pkey_save_amr
+ END_MMU_FTR_SECTION_NESTED_IFSET(MMU_FTR_PKEY , 67)
+
+ BEGIN_MMU_FTR_SECTION_NESTED(68)
+ b 99f // handle_kuap_save_amr
+ MMU_FTR_SECTION_ELSE_NESTED(68)
+ b 100f // skip_save_amr
+ ALT_MMU_FTR_SECTION_END_NESTED_IFSET(MMU_FTR_KUAP, 68)
+
+
+99: // handle_kuap_save_amr
.ifnb \msr_pr_cr
- bne \msr_pr_cr, 99f
+ /*
+ * We avoid changing AMR outside the kernel
+ * hence skip this completely.
+ */
+ bne \msr_pr_cr, 100f // from userspace
.endif
+
+101: // handle_pkey_save_amr
mfspr \gpr1, SPRN_AMR
std \gpr1, STACK_REGS_KUAP(r1)
- li \gpr2, (AMR_KUAP_BLOCKED >> AMR_KUAP_SHIFT)
- sldi \gpr2, \gpr2, AMR_KUAP_SHIFT
+
+ /*
+ * update kernel AMR with AMR_KUAP_BLOCKED only
+ * if KUAP feature is enabled
+ */
+ BEGIN_MMU_FTR_SECTION_NESTED(69)
+ LOAD_REG_IMMEDIATE(\gpr2, AMR_KUAP_BLOCKED)
cmpd \use_cr, \gpr1, \gpr2
- beq \use_cr, 99f
- // We don't isync here because we very recently entered via rfid
+ beq \use_cr, 102f
+ /*
+ * We don't isync here because we very recently entered via an interrupt
+ */
mtspr SPRN_AMR, \gpr2
isync
-99:
- END_MMU_FTR_SECTION_NESTED_IFSET(MMU_FTR_KUAP, 67)
+102:
+ END_MMU_FTR_SECTION_NESTED_IFSET(MMU_FTR_KUAP, 69)
+
+100: // skip_save_amr
#endif
.endm
@@ -62,9 +116,12 @@
#include <asm/mmu.h>
#include <asm/ptrace.h>
-static inline void kuap_restore_amr(struct pt_regs *regs)
+static inline void kuap_restore_amr(struct pt_regs *regs, bool to_user)
{
- if (mmu_has_feature(MMU_FTR_KUAP)) {
+ if (!mmu_has_feature(MMU_FTR_PKEY) && to_user)
+ return;
+
+ if (mmu_has_feature(MMU_FTR_KUAP) || mmu_has_feature(MMU_FTR_PKEY)) {
isync();
mtspr(SPRN_AMR, regs->kuap);
/*
@@ -76,7 +133,8 @@ static inline void kuap_restore_amr(struct pt_regs *regs)
static inline void kuap_check_amr(void)
{
- if (IS_ENABLED(CONFIG_PPC_KUAP_DEBUG) && mmu_has_feature(MMU_FTR_KUAP))
+ if (IS_ENABLED(CONFIG_PPC_KUAP_DEBUG) &&
+ (mmu_has_feature(MMU_FTR_KUAP) || mmu_has_feature(MMU_FTR_PKEY)))
WARN_ON_ONCE(mfspr(SPRN_AMR) != AMR_KUAP_BLOCKED);
}
diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S
index b3c9f15089b6..c2f783dda56d 100644
--- a/arch/powerpc/kernel/entry_64.S
+++ b/arch/powerpc/kernel/entry_64.S
@@ -481,7 +481,7 @@ _ASM_NOKPROBE_SYMBOL(fast_interrupt_return)
kuap_check_amr r3, r4
ld r4,_MSR(r1)
andi. r0,r4,MSR_PR
- bne .Lfast_user_interrupt_return
+ bne .Lfast_user_interrupt_return_amr
kuap_restore_amr r3
andi. r0,r4,MSR_RI
li r3,0 /* 0 return value, no EMULATE_STACK_STORE */
@@ -502,6 +502,8 @@ _ASM_NOKPROBE_SYMBOL(interrupt_return)
cmpdi r3,0
bne- .Lrestore_nvgprs
+.Lfast_user_interrupt_return_amr:
+ kuap_restore_amr r3, 1
.Lfast_user_interrupt_return:
ld r11,_NIP(r1)
ld r12,_MSR(r1)
diff --git a/arch/powerpc/kernel/syscall_64.c b/arch/powerpc/kernel/syscall_64.c
index c0fdb02a13d5..f69b4774f3b3 100644
--- a/arch/powerpc/kernel/syscall_64.c
+++ b/arch/powerpc/kernel/syscall_64.c
@@ -35,7 +35,15 @@ notrace long system_call_exception(long r3, long r4, long r5,
BUG_ON(!FULL_REGS(regs));
BUG_ON(regs->softe != IRQS_ENABLED);
- kuap_check_amr();
+ if (mmu_has_feature(MMU_FTR_PKEY)) {
+ unsigned long amr;
+
+ amr = mfspr(SPRN_AMR);
+ regs->kuap = amr;
+ mtspr(SPRN_AMR, AMR_KUAP_BLOCKED);
+ isync();
+ } else
+ kuap_check_amr();
account_cpu_user_entry();
@@ -208,6 +216,10 @@ notrace unsigned long syscall_exit_prepare(unsigned long r3,
account_cpu_user_exit();
+ /*
+ * We do this at the end so that we do context switch with KERNEL AMR
+ */
+ kuap_restore_amr(regs, true);
return ret;
}
@@ -293,9 +305,12 @@ notrace unsigned long interrupt_exit_user_prepare(struct pt_regs *regs, unsigned
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
local_paca->tm_scratch = regs->msr;
#endif
-
account_cpu_user_exit();
+ /*
+ * We do this at the end so that we do context switch with KERNEL AMR
+ */
+ kuap_restore_amr(regs, true);
return ret;
}
--
2.25.3
^ permalink raw reply related
* [RFC PATCH 14/25] powerpc/book3s64/kuep: Store/restore userspace IAMR correctly on entry and exit from kernel
From: Aneesh Kumar K.V @ 2020-04-27 8:04 UTC (permalink / raw)
To: linuxppc-dev, mpe; +Cc: Aneesh Kumar K.V, linuxram, npiggin
In-Reply-To: <20200427080507.1626327-1-aneesh.kumar@linux.ibm.com>
This prepare kernel to operate with a different value than userspace IAMR.
For this, IAMR needs to be saved and restored on entry and return from the
kernel.
If MMU_FTR_KEY is enabled we always use the key mechanism to implement KUEP
feature. If MMU_FTR_KEY is not supported and if we support MMU_FTR_KUEP
(radix translation on POWER9), we can skip restoring IAMR on return
to userspace. Userspace won't be using IAMR in that specific config.
We don't need to save/restore IAMR on reentry into the kernel due to interrupt
because the kernel doesn't modify IAMR internally.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
---
arch/powerpc/include/asm/book3s/64/kup.h | 51 +++++++++++++++++++++++-
arch/powerpc/include/asm/ptrace.h | 6 ++-
arch/powerpc/kernel/asm-offsets.c | 4 ++
arch/powerpc/kernel/syscall_64.c | 5 ++-
4 files changed, 62 insertions(+), 4 deletions(-)
diff --git a/arch/powerpc/include/asm/book3s/64/kup.h b/arch/powerpc/include/asm/book3s/64/kup.h
index 85645d1b7102..717c2c4d3681 100644
--- a/arch/powerpc/include/asm/book3s/64/kup.h
+++ b/arch/powerpc/include/asm/book3s/64/kup.h
@@ -25,6 +25,13 @@
b 100f // skip_restore_amr
ALT_MMU_FTR_SECTION_END_NESTED_IFSET(MMU_FTR_KUAP, 68)
+ /*
+ * We don't check KUEP feature here, because if FTR_PKEY
+ * is not enabled we don't need to restore IAMR on
+ * return to usespace. That is handled by either
+ * handle_kuap_restore_amr or skip_restore_amr
+ */
+
99: // handle_kuap_restore_amr
/*
* No key support, don't bother to restore AMR
@@ -37,7 +44,17 @@
ld \gpr, STACK_REGS_KUAP(r1)
isync
mtspr SPRN_AMR, \gpr
- /* No isync here because we will return to a different context */
+
+ /*
+ * Restore IAMR only when returning to userspace
+ */
+ .ifnb \to_user
+ ld \gpr, STACK_REGS_KUEP(r1)
+ mtspr SPRN_IAMR, \gpr
+ .endif
+ /*
+ * No isync here because we will return to a different context
+ */
100: // skip_restore_amr
#endif
.endm
@@ -75,6 +92,12 @@
b 100f // skip_save_amr
ALT_MMU_FTR_SECTION_END_NESTED_IFSET(MMU_FTR_KUAP, 68)
+ /*
+ * We don't check KUEP feature here, because if FTR_PKEY
+ * is not enabled we don't need to save IAMR on
+ * entry from usespace. That is handled by either
+ * handle_kuap_save_amr or skip_save_amr
+ */
99: // handle_kuap_save_amr
.ifnb \msr_pr_cr
@@ -103,7 +126,26 @@
mtspr SPRN_AMR, \gpr2
isync
102:
- END_MMU_FTR_SECTION_NESTED_IFSET(MMU_FTR_KUAP, 69)
+ END_MMU_FTR_SECTION_NESTED_IFSET(MMU_FTR_KUAP, 69)
+
+ .ifnb \msr_pr_cr
+ beq \msr_pr_cr, 103f // from kernel space
+ mfspr \gpr1, SPRN_IAMR
+ std \gpr1, STACK_REGS_KUEP(r1)
+
+ /*
+ * update kernel IAMR with AMR_KUEP_BLOCKED only
+ * if KUAP feature is enabled
+ */
+ BEGIN_MMU_FTR_SECTION_NESTED(70)
+ LOAD_REG_IMMEDIATE(\gpr2, AMR_KUEP_BLOCKED)
+ cmpd \use_cr, \gpr1, \gpr2
+ beq \use_cr, 103f
+ mtspr SPRN_IAMR, \gpr2
+ isync
+103:
+ END_MMU_FTR_SECTION_NESTED_IFSET(MMU_FTR_KUEP, 70)
+ .endif
100: // skip_save_amr
#endif
@@ -129,6 +171,11 @@ static inline void kuap_restore_amr(struct pt_regs *regs, bool to_user)
* returning to a different context using rfid
*/
}
+ /*
+ * We do support FTR_PKEY, restore IAMR when returning to user
+ */
+ if (to_user)
+ mtspr(SPRN_IAMR, regs->kuep);
}
static inline void kuap_check_amr(void)
diff --git a/arch/powerpc/include/asm/ptrace.h b/arch/powerpc/include/asm/ptrace.h
index e0195e6b892b..2bfd2b6a72ab 100644
--- a/arch/powerpc/include/asm/ptrace.h
+++ b/arch/powerpc/include/asm/ptrace.h
@@ -56,8 +56,12 @@ struct pt_regs
#ifdef CONFIG_PPC_KUAP
unsigned long kuap;
#endif
+#ifdef CONFIG_PPC_KUEP
+ unsigned long kuep;
+#endif
+
};
- unsigned long __pad[2]; /* Maintain 16 byte interrupt stack alignment */
+ unsigned long __pad[4]; /* Maintain 16 byte interrupt stack alignment */
};
};
#endif
diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c
index fcf24a365fc0..6c7326fc73b9 100644
--- a/arch/powerpc/kernel/asm-offsets.c
+++ b/arch/powerpc/kernel/asm-offsets.c
@@ -353,6 +353,10 @@ int main(void)
#ifdef CONFIG_PPC_KUAP
STACK_PT_REGS_OFFSET(STACK_REGS_KUAP, kuap);
#endif
+#ifdef CONFIG_PPC_KUEP
+ STACK_PT_REGS_OFFSET(STACK_REGS_KUEP, kuep);
+#endif
+
#if defined(CONFIG_PPC32)
#if defined(CONFIG_BOOKE) || defined(CONFIG_40x)
diff --git a/arch/powerpc/kernel/syscall_64.c b/arch/powerpc/kernel/syscall_64.c
index f69b4774f3b3..458f2bb80c6d 100644
--- a/arch/powerpc/kernel/syscall_64.c
+++ b/arch/powerpc/kernel/syscall_64.c
@@ -36,11 +36,14 @@ notrace long system_call_exception(long r3, long r4, long r5,
BUG_ON(regs->softe != IRQS_ENABLED);
if (mmu_has_feature(MMU_FTR_PKEY)) {
- unsigned long amr;
+ unsigned long amr, iamr;
amr = mfspr(SPRN_AMR);
+ iamr = mfspr(SPRN_IAMR);
regs->kuap = amr;
+ regs->kuep = iamr;
mtspr(SPRN_AMR, AMR_KUAP_BLOCKED);
+ mtspr(SPRN_IAMR, AMR_KUEP_BLOCKED);
isync();
} else
kuap_check_amr();
--
2.25.3
^ permalink raw reply related
* [RFC PATCH 15/25] powerpc/book3s64/pkeys: Inherit correctly on fork.
From: Aneesh Kumar K.V @ 2020-04-27 8:04 UTC (permalink / raw)
To: linuxppc-dev, mpe; +Cc: Aneesh Kumar K.V, linuxram, npiggin
In-Reply-To: <20200427080507.1626327-1-aneesh.kumar@linux.ibm.com>
Child thread.kuap value is inherited from the parent in copy_thread_tls. We still
need to make sure when the child returns from a fork in the kernel we start with the kernel
default AMR value.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
---
arch/powerpc/kernel/process.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index 78eedf0b5c30..fc4cc32d4726 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -1698,6 +1698,11 @@ int copy_thread_tls(unsigned long clone_flags, unsigned long usp,
p->thread.tidr = 0;
#endif
+ /*
+ * Run with the current AMR value of the kernel
+ */
+ kregs->kuap = AMR_KUAP_BLOCKED;
+ kregs->kuep = AMR_KUEP_BLOCKED;
kregs->nip = ppc_function_entry(f);
return 0;
}
--
2.25.3
^ permalink raw reply related
* [RFC PATCH 16/25] powerpc/book3s64/pkeys: Reset userspace AMR correctly on exec
From: Aneesh Kumar K.V @ 2020-04-27 8:04 UTC (permalink / raw)
To: linuxppc-dev, mpe; +Cc: Aneesh Kumar K.V, linuxram, npiggin
In-Reply-To: <20200427080507.1626327-1-aneesh.kumar@linux.ibm.com>
On fork, we inherit from the parent and on exec, we should switch to default_amr values.
Also, avoid changing the AMR register value within the kernel. The kernel now runs with
different AMR values.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
---
arch/powerpc/include/asm/pkeys.h | 1 +
arch/powerpc/kernel/process.c | 3 ++-
arch/powerpc/mm/book3s64/pkeys.c | 16 +---------------
3 files changed, 4 insertions(+), 16 deletions(-)
diff --git a/arch/powerpc/include/asm/pkeys.h b/arch/powerpc/include/asm/pkeys.h
index 6e8157f78b52..cd1a03044814 100644
--- a/arch/powerpc/include/asm/pkeys.h
+++ b/arch/powerpc/include/asm/pkeys.h
@@ -13,6 +13,7 @@
extern int max_pkey;
extern u64 default_uamor;
+extern u64 default_amr;
extern u32 reserved_allocation_mask; /* bits set for reserved keys */
#define ARCH_VM_PKEY_FLAGS (VM_PKEY_BIT0 | VM_PKEY_BIT1 | VM_PKEY_BIT2 | \
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index fc4cc32d4726..9660bab1d99d 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -1473,6 +1473,8 @@ void arch_setup_new_exec(void)
current->thread.regs = regs - 1;
}
+ current->thread.regs->kuap = default_amr;
+ current->thread.regs->kuep = default_iamr;
}
#endif
@@ -1827,7 +1829,6 @@ void start_thread(struct pt_regs *regs, unsigned long start, unsigned long sp)
current->thread.load_tm = 0;
#endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
- thread_pkey_regs_init(¤t->thread);
}
EXPORT_SYMBOL(start_thread);
diff --git a/arch/powerpc/mm/book3s64/pkeys.c b/arch/powerpc/mm/book3s64/pkeys.c
index d0d781876c20..42ca7aa09d5b 100644
--- a/arch/powerpc/mm/book3s64/pkeys.c
+++ b/arch/powerpc/mm/book3s64/pkeys.c
@@ -20,7 +20,7 @@ int max_pkey; /* Maximum key value supported */
*/
u32 reserved_allocation_mask;
static u32 initial_allocation_mask; /* Bits set for the initially allocated keys */
-static u64 default_amr;
+u64 default_amr;
static u64 default_iamr;
/* Allow all keys to be modified by default */
u64 default_uamor = ~0x0UL;
@@ -387,20 +387,6 @@ void thread_pkey_regs_restore(struct thread_struct *new_thread,
write_uamor(new_thread->uamor);
}
-void thread_pkey_regs_init(struct thread_struct *thread)
-{
- if (!mmu_has_feature(MMU_FTR_PKEY))
- return;
-
- thread->amr = default_amr;
- thread->iamr = default_iamr;
- thread->uamor = default_uamor;
-
- write_amr(default_amr);
- write_iamr(default_iamr);
- write_uamor(default_uamor);
-}
-
int execute_only_pkey(struct mm_struct *mm)
{
if (static_branch_likely(&execute_pkey_disabled))
--
2.25.3
^ permalink raw reply related
* [RFC PATCH 17/25] powerpc/ptrace-view: Use pt_regs values instead of thread_struct based one.
From: Aneesh Kumar K.V @ 2020-04-27 8:04 UTC (permalink / raw)
To: linuxppc-dev, mpe; +Cc: Aneesh Kumar K.V, linuxram, npiggin
In-Reply-To: <20200427080507.1626327-1-aneesh.kumar@linux.ibm.com>
We will remove thread.amr/iamr/uamor in a later patch
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
---
arch/powerpc/kernel/ptrace/ptrace-view.c | 23 +++++++++++++++++------
1 file changed, 17 insertions(+), 6 deletions(-)
diff --git a/arch/powerpc/kernel/ptrace/ptrace-view.c b/arch/powerpc/kernel/ptrace/ptrace-view.c
index 15e3b79b6395..5b7bea41c699 100644
--- a/arch/powerpc/kernel/ptrace/ptrace-view.c
+++ b/arch/powerpc/kernel/ptrace/ptrace-view.c
@@ -488,14 +488,25 @@ static int pkey_active(struct task_struct *target, const struct user_regset *reg
static int pkey_get(struct task_struct *target, const struct user_regset *regset,
unsigned int pos, unsigned int count, void *kbuf, void __user *ubuf)
{
- BUILD_BUG_ON(TSO(amr) + sizeof(unsigned long) != TSO(iamr));
- BUILD_BUG_ON(TSO(iamr) + sizeof(unsigned long) != TSO(uamor));
+ int ret;
if (!arch_pkeys_enabled())
return -ENODEV;
- return user_regset_copyout(&pos, &count, &kbuf, &ubuf, &target->thread.amr,
- 0, ELF_NPKEY * sizeof(unsigned long));
+ ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, &target->thread.regs->kuap,
+ 0, 1 * sizeof(unsigned long));
+ if (ret)
+ goto err_out;
+
+ ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, &target->thread.regs->kuep,
+ 1 * sizeof(unsigned long), 2 * sizeof(unsigned long));
+ if (ret)
+ goto err_out;
+
+ ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, &default_uamor,
+ 2 * sizeof(unsigned long), 3 * sizeof(unsigned long));
+err_out:
+ return ret;
}
static int pkey_set(struct task_struct *target, const struct user_regset *regset,
@@ -518,8 +529,8 @@ static int pkey_set(struct task_struct *target, const struct user_regset *regset
return ret;
/* UAMOR determines which bits of the AMR can be set from userspace. */
- target->thread.amr = (new_amr & target->thread.uamor) |
- (target->thread.amr & ~target->thread.uamor);
+ target->thread.regs->kuap = (new_amr & default_uamor) |
+ (target->thread.regs->kuap & ~default_uamor);
return 0;
}
--
2.25.3
^ permalink raw reply related
* [RFC PATCH 18/25] powerpc/book3s64/pkeys: Don't update SPRN_AMR when in kernel mode.
From: Aneesh Kumar K.V @ 2020-04-27 8:04 UTC (permalink / raw)
To: linuxppc-dev, mpe; +Cc: Aneesh Kumar K.V, linuxram, npiggin
In-Reply-To: <20200427080507.1626327-1-aneesh.kumar@linux.ibm.com>
Now that kernel correctly store/restore userspace AMR/IAMR values, avoid
manipulating AMR and IAMR from the kernel on behalf of userspace.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
---
arch/powerpc/include/asm/book3s/64/kup.h | 27 +++++++++
arch/powerpc/include/asm/pkeys.h | 2 -
arch/powerpc/include/asm/processor.h | 5 --
arch/powerpc/kernel/process.c | 4 --
arch/powerpc/kernel/traps.c | 6 --
arch/powerpc/mm/book3s64/pkeys.c | 73 ++++--------------------
6 files changed, 39 insertions(+), 78 deletions(-)
diff --git a/arch/powerpc/include/asm/book3s/64/kup.h b/arch/powerpc/include/asm/book3s/64/kup.h
index 717c2c4d3681..6a706e6fef59 100644
--- a/arch/powerpc/include/asm/book3s/64/kup.h
+++ b/arch/powerpc/include/asm/book3s/64/kup.h
@@ -158,6 +158,33 @@
#include <asm/mmu.h>
#include <asm/ptrace.h>
+extern u64 default_uamor;
+extern u64 default_amr;
+extern u64 default_iamr;
+
+/*
+ * For kernel thread that doesn't have thread.regs return
+ * default AMR/IAMR values.
+ */
+static inline u64 current_thread_amr(void)
+{
+ if (current->thread.regs)
+ return current->thread.regs->kuap;
+ return AMR_KUAP_BLOCKED;
+}
+
+static inline u64 current_thread_iamr(void)
+{
+ if (current->thread.regs)
+ return current->thread.regs->kuep;
+ return AMR_KUEP_BLOCKED;
+}
+
+static inline u64 read_uamor(void)
+{
+ return default_uamor;
+}
+
static inline void kuap_restore_amr(struct pt_regs *regs, bool to_user)
{
if (!mmu_has_feature(MMU_FTR_PKEY) && to_user)
diff --git a/arch/powerpc/include/asm/pkeys.h b/arch/powerpc/include/asm/pkeys.h
index cd1a03044814..b1d448c53209 100644
--- a/arch/powerpc/include/asm/pkeys.h
+++ b/arch/powerpc/include/asm/pkeys.h
@@ -12,8 +12,6 @@
#include <asm/firmware.h>
extern int max_pkey;
-extern u64 default_uamor;
-extern u64 default_amr;
extern u32 reserved_allocation_mask; /* bits set for reserved keys */
#define ARCH_VM_PKEY_FLAGS (VM_PKEY_BIT0 | VM_PKEY_BIT1 | VM_PKEY_BIT2 | \
diff --git a/arch/powerpc/include/asm/processor.h b/arch/powerpc/include/asm/processor.h
index eedcbfb9a6ff..3cef707b27c7 100644
--- a/arch/powerpc/include/asm/processor.h
+++ b/arch/powerpc/include/asm/processor.h
@@ -234,11 +234,6 @@ struct thread_struct {
struct thread_vr_state ckvr_state; /* Checkpointed VR state */
unsigned long ckvrsave; /* Checkpointed VRSAVE */
#endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
-#ifdef CONFIG_PPC_MEM_KEYS
- unsigned long amr;
- unsigned long iamr;
- unsigned long uamor;
-#endif
#ifdef CONFIG_KVM_BOOK3S_32_HANDLER
void* kvm_shadow_vcpu; /* KVM internal data */
#endif /* CONFIG_KVM_BOOK3S_32_HANDLER */
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index 9660bab1d99d..17f65a2738bc 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -585,7 +585,6 @@ static void save_all(struct task_struct *tsk)
__giveup_spe(tsk);
msr_check_and_clear(msr_all_available);
- thread_pkey_regs_save(&tsk->thread);
}
void flush_all_to_thread(struct task_struct *tsk)
@@ -1097,8 +1096,6 @@ static inline void save_sprs(struct thread_struct *t)
t->tar = mfspr(SPRN_TAR);
}
#endif
-
- thread_pkey_regs_save(t);
}
static inline void restore_sprs(struct thread_struct *old_thread,
@@ -1139,7 +1136,6 @@ static inline void restore_sprs(struct thread_struct *old_thread,
mtspr(SPRN_TIDR, new_thread->tidr);
#endif
- thread_pkey_regs_restore(new_thread, old_thread);
}
struct task_struct *__switch_to(struct task_struct *prev,
diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
index 3fca22276bb1..a47fb49b7af8 100644
--- a/arch/powerpc/kernel/traps.c
+++ b/arch/powerpc/kernel/traps.c
@@ -348,12 +348,6 @@ static bool exception_common(int signr, struct pt_regs *regs, int code,
current->thread.trap_nr = code;
- /*
- * Save all the pkey registers AMR/IAMR/UAMOR. Eg: Core dumps need
- * to capture the content, if the task gets killed.
- */
- thread_pkey_regs_save(¤t->thread);
-
return true;
}
diff --git a/arch/powerpc/mm/book3s64/pkeys.c b/arch/powerpc/mm/book3s64/pkeys.c
index 42ca7aa09d5b..2484d8502499 100644
--- a/arch/powerpc/mm/book3s64/pkeys.c
+++ b/arch/powerpc/mm/book3s64/pkeys.c
@@ -21,7 +21,7 @@ int max_pkey; /* Maximum key value supported */
u32 reserved_allocation_mask;
static u32 initial_allocation_mask; /* Bits set for the initially allocated keys */
u64 default_amr;
-static u64 default_iamr;
+u64 default_iamr;
/* Allow all keys to be modified by default */
u64 default_uamor = ~0x0UL;
/*
@@ -264,40 +264,17 @@ void pkey_mm_init(struct mm_struct *mm)
mm->context.execute_only_pkey = execute_only_key;
}
-static inline u64 read_amr(void)
+static inline void update_current_thread_amr(u64 value)
{
- return mfspr(SPRN_AMR);
+ current->thread.regs->kuap = value;
}
-static inline void write_amr(u64 value)
-{
- mtspr(SPRN_AMR, value);
-}
-
-static inline u64 read_iamr(void)
-{
- if (static_branch_unlikely(&execute_pkey_disabled))
- return 0x0UL;
-
- return mfspr(SPRN_IAMR);
-}
-
-static inline void write_iamr(u64 value)
+static inline void update_current_thread_iamr(u64 value)
{
if (static_branch_unlikely(&execute_pkey_disabled))
return;
- mtspr(SPRN_IAMR, value);
-}
-
-static inline u64 read_uamor(void)
-{
- return mfspr(SPRN_UAMOR);
-}
-
-static inline void write_uamor(u64 value)
-{
- mtspr(SPRN_UAMOR, value);
+ current->thread.regs->kuep = value;
}
static bool is_pkey_enabled(int pkey)
@@ -314,20 +291,21 @@ static bool is_pkey_enabled(int pkey)
return !!(uamor_pkey_bits);
}
+/* FIXME!! what happens to other threads AMR value? */
static inline void init_amr(int pkey, u8 init_bits)
{
u64 new_amr_bits = (((u64)init_bits & 0x3UL) << pkeyshift(pkey));
- u64 old_amr = read_amr() & ~((u64)(0x3ul) << pkeyshift(pkey));
+ u64 old_amr = current_thread_amr() & ~((u64)(0x3ul) << pkeyshift(pkey));
- write_amr(old_amr | new_amr_bits);
+ update_current_thread_amr(old_amr | new_amr_bits);
}
static inline void init_iamr(int pkey, u8 init_bits)
{
u64 new_iamr_bits = (((u64)init_bits & 0x1UL) << pkeyshift(pkey));
- u64 old_iamr = read_iamr() & ~((u64)(0x1ul) << pkeyshift(pkey));
+ u64 old_iamr = current_thread_iamr() & ~((u64)(0x1ul) << pkeyshift(pkey));
- write_iamr(old_iamr | new_iamr_bits);
+ update_current_thread_iamr(old_iamr | new_iamr_bits);
}
/*
@@ -360,33 +338,6 @@ int __arch_set_user_pkey_access(struct task_struct *tsk, int pkey,
return 0;
}
-void thread_pkey_regs_save(struct thread_struct *thread)
-{
- if (!mmu_has_feature(MMU_FTR_PKEY))
- return;
-
- /*
- * TODO: Skip saving registers if @thread hasn't used any keys yet.
- */
- thread->amr = read_amr();
- thread->iamr = read_iamr();
- thread->uamor = read_uamor();
-}
-
-void thread_pkey_regs_restore(struct thread_struct *new_thread,
- struct thread_struct *old_thread)
-{
- if (!mmu_has_feature(MMU_FTR_PKEY))
- return;
-
- if (old_thread->amr != new_thread->amr)
- write_amr(new_thread->amr);
- if (old_thread->iamr != new_thread->iamr)
- write_iamr(new_thread->iamr);
- if (old_thread->uamor != new_thread->uamor)
- write_uamor(new_thread->uamor);
-}
-
int execute_only_pkey(struct mm_struct *mm)
{
if (static_branch_likely(&execute_pkey_disabled))
@@ -440,10 +391,10 @@ static bool pkey_access_permitted(int pkey, bool write, bool execute)
return true;
pkey_shift = pkeyshift(pkey);
- if (execute && !(read_iamr() & (IAMR_EX_BIT << pkey_shift)))
+ if (execute && !(current_thread_iamr() & (IAMR_EX_BIT << pkey_shift)))
return true;
- amr = read_amr(); /* Delay reading amr until absolutely needed */
+ amr = current_thread_amr();
return ((!write && !(amr & (AMR_RD_BIT << pkey_shift))) ||
(write && !(amr & (AMR_WR_BIT << pkey_shift))));
}
--
2.25.3
^ permalink raw reply related
* [RFC PATCH 23/25] powerpc/book3s64/hash/kuap: Enable kuap on hash
From: Aneesh Kumar K.V @ 2020-04-27 8:05 UTC (permalink / raw)
To: linuxppc-dev, mpe; +Cc: Aneesh Kumar K.V, linuxram, npiggin
In-Reply-To: <20200427080507.1626327-1-aneesh.kumar@linux.ibm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
---
arch/powerpc/mm/book3s64/pkeys.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/arch/powerpc/mm/book3s64/pkeys.c b/arch/powerpc/mm/book3s64/pkeys.c
index 2484d8502499..40b6240ecc89 100644
--- a/arch/powerpc/mm/book3s64/pkeys.c
+++ b/arch/powerpc/mm/book3s64/pkeys.c
@@ -240,7 +240,12 @@ void setup_kuep(bool disabled)
#ifdef CONFIG_PPC_KUAP
void setup_kuap(bool disabled)
{
- if (disabled || !early_radix_enabled())
+ if (disabled)
+ return;
+ /*
+ * On hash if PKEY feature is not enabled, disable KUAP too.
+ */
+ if (!early_radix_enabled() && !early_mmu_has_feature(MMU_FTR_PKEY))
return;
if (smp_processor_id() == boot_cpuid) {
--
2.25.3
^ permalink raw reply related
* [RFC PATCH 20/25] powerpc/book3s64/kuap: Improve error reporting with KUAP
From: Aneesh Kumar K.V @ 2020-04-27 8:05 UTC (permalink / raw)
To: linuxppc-dev, mpe; +Cc: Aneesh Kumar K.V, linuxram, npiggin
In-Reply-To: <20200427080507.1626327-1-aneesh.kumar@linux.ibm.com>
With hash translation use DSISR_KEYFAULT to identify a wrong access.
With Radix we look at the AMR value and type of fault.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
---
arch/powerpc/include/asm/book3s/64/kup.h | 7 ------
arch/powerpc/mm/fault.c | 27 +++++++++++++++++++++++-
2 files changed, 26 insertions(+), 8 deletions(-)
diff --git a/arch/powerpc/include/asm/book3s/64/kup.h b/arch/powerpc/include/asm/book3s/64/kup.h
index 590c1d9455d1..f564d909e195 100644
--- a/arch/powerpc/include/asm/book3s/64/kup.h
+++ b/arch/powerpc/include/asm/book3s/64/kup.h
@@ -280,13 +280,6 @@ static inline void restore_user_access(unsigned long flags)
set_kuap(flags);
}
-static inline bool
-bad_kuap_fault(struct pt_regs *regs, unsigned long address, bool is_write)
-{
- return WARN(mmu_has_feature(MMU_FTR_KUAP) &&
- (regs->kuap & (is_write ? AMR_KUAP_BLOCK_WRITE : AMR_KUAP_BLOCK_READ)),
- "Bug: %s fault blocked by AMR!", is_write ? "Write" : "Read");
-}
#else /* CONFIG_PPC_KUAP */
static inline void kuap_restore_amr(struct pt_regs *regs)
{
diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c
index 84af6c8eecf7..4f866b11512c 100644
--- a/arch/powerpc/mm/fault.c
+++ b/arch/powerpc/mm/fault.c
@@ -198,6 +198,31 @@ static int mm_fault_error(struct pt_regs *regs, unsigned long addr,
return 0;
}
+#define RADIX_KUAP_BLOCK_READ UL(0x4000000000000000)
+#define RADIX_KUAP_BLOCK_WRITE UL(0x8000000000000000)
+
+static bool bad_kuap_fault(struct pt_regs *regs, unsigned long address,
+ bool is_write, unsigned long error_code)
+{
+ if (!mmu_has_feature(MMU_FTR_KUAP))
+ return false;
+
+ if (radix_enabled()) {
+ /*
+ * Will be a storage protection fault.
+ * Only check the details of AMR[0]
+ */
+ return WARN((regs->kuap & (is_write ? RADIX_KUAP_BLOCK_WRITE : RADIX_KUAP_BLOCK_READ)),
+ "Bug: %s fault blocked by AMR!", is_write ? "Write" : "Read");
+ }
+ /*
+ * We don't want to WARN here because userspace can setup
+ * keys such that a kernel access to user address can cause
+ * fault
+ */
+ return !!(error_code & DSISR_KEYFAULT);
+}
+
/* Is this a bad kernel fault ? */
static bool bad_kernel_fault(struct pt_regs *regs, unsigned long error_code,
unsigned long address, bool is_write)
@@ -233,7 +258,7 @@ static bool bad_kernel_fault(struct pt_regs *regs, unsigned long error_code,
// Read/write fault in a valid region (the exception table search passed
// above), but blocked by KUAP is bad, it can never succeed.
- if (bad_kuap_fault(regs, address, is_write))
+ if (bad_kuap_fault(regs, address, is_write, error_code))
return true;
// What's left? Kernel fault on user in well defined regions (extable
--
2.25.3
^ permalink raw reply related
* [RFC PATCH 21/25] powerpc/book3s64/kuap: Use Key 3 to implement KUAP with hash translation.
From: Aneesh Kumar K.V @ 2020-04-27 8:05 UTC (permalink / raw)
To: linuxppc-dev, mpe; +Cc: Aneesh Kumar K.V, linuxram, npiggin
In-Reply-To: <20200427080507.1626327-1-aneesh.kumar@linux.ibm.com>
Radix use AMR Key 0 and hash translation use AMR key 3.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
---
arch/powerpc/include/asm/book3s/64/kup.h | 9 ++++-----
1 file changed, 4 insertions(+), 5 deletions(-)
diff --git a/arch/powerpc/include/asm/book3s/64/kup.h b/arch/powerpc/include/asm/book3s/64/kup.h
index f564d909e195..7ccbe2653273 100644
--- a/arch/powerpc/include/asm/book3s/64/kup.h
+++ b/arch/powerpc/include/asm/book3s/64/kup.h
@@ -5,11 +5,10 @@
#include <linux/const.h>
#include <asm/reg.h>
-#define AMR_KUAP_BLOCK_READ UL(0x4000000000000000)
-#define AMR_KUAP_BLOCK_WRITE UL(0x8000000000000000)
+#define AMR_KUAP_BLOCK_READ UL(0x5455555555555555)
+#define AMR_KUAP_BLOCK_WRITE UL(0xa8aaaaaaaaaaaaaa)
#define AMR_KUEP_BLOCKED (1UL << 62)
#define AMR_KUAP_BLOCKED (AMR_KUAP_BLOCK_READ | AMR_KUAP_BLOCK_WRITE)
-#define AMR_KUAP_SHIFT 62
#ifdef __ASSEMBLY__
@@ -63,8 +62,8 @@
#ifdef CONFIG_PPC_KUAP_DEBUG
BEGIN_MMU_FTR_SECTION_NESTED(67)
mfspr \gpr1, SPRN_AMR
- li \gpr2, (AMR_KUAP_BLOCKED >> AMR_KUAP_SHIFT)
- sldi \gpr2, \gpr2, AMR_KUAP_SHIFT
+ /* Prevent access to userspace using any key values */
+ LOAD_REG_IMMEDIATE(\gpr2, AMR_KUAP_BLOCKED)
999: tdne \gpr1, \gpr2
EMIT_BUG_ENTRY 999b, __FILE__, __LINE__, (BUGFLAG_WARNING | BUGFLAG_ONCE)
END_MMU_FTR_SECTION_NESTED_IFSET(MMU_FTR_KUAP, 67)
--
2.25.3
^ permalink raw reply related
* [RFC PATCH 25/25] powerpc/book3s64/keys: Print information during boot.
From: Aneesh Kumar K.V @ 2020-04-27 8:05 UTC (permalink / raw)
To: linuxppc-dev, mpe; +Cc: Aneesh Kumar K.V, linuxram, npiggin
In-Reply-To: <20200427080507.1626327-1-aneesh.kumar@linux.ibm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
---
arch/powerpc/mm/book3s64/pkeys.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/arch/powerpc/mm/book3s64/pkeys.c b/arch/powerpc/mm/book3s64/pkeys.c
index a1952ee6668e..660e0691db07 100644
--- a/arch/powerpc/mm/book3s64/pkeys.c
+++ b/arch/powerpc/mm/book3s64/pkeys.c
@@ -207,6 +207,7 @@ void __init pkey_early_init_devtree(void)
*/
initial_allocation_mask |= reserved_allocation_mask;
+ pr_info("Enabling Memory keys with max key count %d", max_pkey);
err_out:
/*
* Setup uamor on boot cpu
--
2.25.3
^ permalink raw reply related
* [RFC PATCH 22/25] powerpc/book3s64/kuep: Use Key 3 to implement KUEP with hash translation.
From: Aneesh Kumar K.V @ 2020-04-27 8:05 UTC (permalink / raw)
To: linuxppc-dev, mpe; +Cc: Aneesh Kumar K.V, linuxram, npiggin
In-Reply-To: <20200427080507.1626327-1-aneesh.kumar@linux.ibm.com>
Radix use IAMR Key 0 and hash translation use IAMR key 3.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
---
arch/powerpc/include/asm/book3s/64/kup.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/powerpc/include/asm/book3s/64/kup.h b/arch/powerpc/include/asm/book3s/64/kup.h
index 7ccbe2653273..ae03b6341f88 100644
--- a/arch/powerpc/include/asm/book3s/64/kup.h
+++ b/arch/powerpc/include/asm/book3s/64/kup.h
@@ -7,7 +7,7 @@
#define AMR_KUAP_BLOCK_READ UL(0x5455555555555555)
#define AMR_KUAP_BLOCK_WRITE UL(0xa8aaaaaaaaaaaaaa)
-#define AMR_KUEP_BLOCKED (1UL << 62)
+#define AMR_KUEP_BLOCKED UL(0x5455555555555555)
#define AMR_KUAP_BLOCKED (AMR_KUAP_BLOCK_READ | AMR_KUAP_BLOCK_WRITE)
#ifdef __ASSEMBLY__
--
2.25.3
^ permalink raw reply related
* [RFC PATCH 24/25] powerpc/book3s64/hash/kuep: Enable KUEP on hash
From: Aneesh Kumar K.V @ 2020-04-27 8:05 UTC (permalink / raw)
To: linuxppc-dev, mpe; +Cc: Aneesh Kumar K.V, linuxram, npiggin
In-Reply-To: <20200427080507.1626327-1-aneesh.kumar@linux.ibm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
---
arch/powerpc/mm/book3s64/pkeys.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/arch/powerpc/mm/book3s64/pkeys.c b/arch/powerpc/mm/book3s64/pkeys.c
index 40b6240ecc89..a1952ee6668e 100644
--- a/arch/powerpc/mm/book3s64/pkeys.c
+++ b/arch/powerpc/mm/book3s64/pkeys.c
@@ -219,7 +219,12 @@ void __init pkey_early_init_devtree(void)
#ifdef CONFIG_PPC_KUEP
void setup_kuep(bool disabled)
{
- if (disabled || !early_radix_enabled())
+ if (disabled)
+ return;
+ /*
+ * On hash if PKEY feature is not enabled, disable KUAP too.
+ */
+ if (!early_radix_enabled() && !early_mmu_has_feature(MMU_FTR_PKEY))
return;
if (smp_processor_id() == boot_cpuid) {
--
2.25.3
^ permalink raw reply related
* [RFC PATCH 19/25] powerpc/book3s64/kuap: Restrict access to userspace based on userspace AMR
From: Aneesh Kumar K.V @ 2020-04-27 8:05 UTC (permalink / raw)
To: linuxppc-dev, mpe; +Cc: Aneesh Kumar K.V, linuxram, npiggin
In-Reply-To: <20200427080507.1626327-1-aneesh.kumar@linux.ibm.com>
If an application has configured address protection such that read/write is
denied using pkey even the kernel should receive a FAULT on accessing the same.
This patch use user AMR value stored in pt_regs.kuap to achieve the same.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
---
arch/powerpc/include/asm/book3s/64/kup.h | 12 +++++++++---
1 file changed, 9 insertions(+), 3 deletions(-)
diff --git a/arch/powerpc/include/asm/book3s/64/kup.h b/arch/powerpc/include/asm/book3s/64/kup.h
index 6a706e6fef59..590c1d9455d1 100644
--- a/arch/powerpc/include/asm/book3s/64/kup.h
+++ b/arch/powerpc/include/asm/book3s/64/kup.h
@@ -242,14 +242,20 @@ static inline void set_kuap(unsigned long value)
static __always_inline void allow_user_access(void __user *to, const void __user *from,
unsigned long size, unsigned long dir)
{
+ unsigned long thread_amr = 0;
+
// This is written so we can resolve to a single case at build time
BUILD_BUG_ON(!__builtin_constant_p(dir));
+
+ if (mmu_has_feature(MMU_FTR_PKEY))
+ thread_amr = current_thread_amr();
+
if (dir == KUAP_READ)
- set_kuap(AMR_KUAP_BLOCK_WRITE);
+ set_kuap(thread_amr | AMR_KUAP_BLOCK_WRITE);
else if (dir == KUAP_WRITE)
- set_kuap(AMR_KUAP_BLOCK_READ);
+ set_kuap(thread_amr | AMR_KUAP_BLOCK_READ);
else if (dir == KUAP_READ_WRITE)
- set_kuap(0);
+ set_kuap(thread_amr);
else
BUILD_BUG();
}
--
2.25.3
^ permalink raw reply related
* Re: [RFC 1/3] powernv/cpuidle : Support for pre-entry and post exit of stop state in firmware
From: Gautham R Shenoy @ 2020-04-27 10:26 UTC (permalink / raw)
To: Abhishek Goel
Cc: ego, mikey, linux-kernel, npiggin, linuxppc-dev, oohall, psampat
In-Reply-To: <20200427021027.114582-1-huntbag@linux.vnet.ibm.com>
Hi Abhishek,
On Sun, Apr 26, 2020 at 09:10:25PM -0500, Abhishek Goel wrote:
> This patch provides kernel framework fro opal support of save restore
> of sprs in idle stop loop. Opal support for stop states is needed to
> selectively enable stop states or to introduce a quirk quickly in case
> a buggy stop state is present.
>
> We make a opal call from kernel if firmware-stop-support for stop
> states is present and enabled. All the quirks for pre-entry of stop
> state is handled inside opal. A call from opal is made into kernel
> where we execute stop afer saving of NVGPRs.
> After waking up from 0x100 vector in kernel, we enter back into opal.
> All the quirks in post exit path, if any, are then handled in opal,
> from where we return successfully back to kernel.
> For deep stop states in which additional SPRs are lost, saving and
> restoration will be done in OPAL.
>
> This idea was first proposed by Nick here:
> https://patchwork.ozlabs.org/patch/1208159/
>
> The corresponding skiboot patch for this kernel patch is here:
> https://patchwork.ozlabs.org/project/skiboot/list/?series=172831
>
> When we callback from OPAL into kernel, r13 is clobbered. So, to
> access PACA we need to restore it from HSPRGO. In future we can
> handle this into OPAL as in here:
> https://patchwork.ozlabs.org/patch/1245275/
>
> Signed-off-by: Abhishek Goel <huntbag@linux.vnet.ibm.com>
> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
> ---
>
> v1->v2 : No change in this patch.
>
> arch/powerpc/include/asm/opal-api.h | 8 ++++-
> arch/powerpc/include/asm/opal.h | 3 ++
> arch/powerpc/kernel/idle_book3s.S | 5 +++
> arch/powerpc/platforms/powernv/idle.c | 37 ++++++++++++++++++++++
> arch/powerpc/platforms/powernv/opal-call.c | 2 ++
> 5 files changed, 54 insertions(+), 1 deletion(-)
>
> diff --git a/arch/powerpc/include/asm/opal-api.h b/arch/powerpc/include/asm/opal-api.h
> index c1f25a760eb1..a2c782c99c9e 100644
> --- a/arch/powerpc/include/asm/opal-api.h
> +++ b/arch/powerpc/include/asm/opal-api.h
> @@ -214,7 +214,9 @@
> #define OPAL_SECVAR_GET 176
> #define OPAL_SECVAR_GET_NEXT 177
> #define OPAL_SECVAR_ENQUEUE_UPDATE 178
> -#define OPAL_LAST 178
> +#define OPAL_REGISTER_OS_OPS 181
> +#define OPAL_CPU_IDLE 182
> +#define OPAL_LAST 182
>
> #define QUIESCE_HOLD 1 /* Spin all calls at entry */
> #define QUIESCE_REJECT 2 /* Fail all calls with OPAL_BUSY */
> @@ -1181,6 +1183,10 @@ struct opal_mpipl_fadump {
> struct opal_mpipl_region region[];
> } __packed;
>
> +struct opal_os_ops {
> + __be64 os_idle_stop;
> +};
> +
> #endif /* __ASSEMBLY__ */
>
> #endif /* __OPAL_API_H */
> diff --git a/arch/powerpc/include/asm/opal.h b/arch/powerpc/include/asm/opal.h
> index 9986ac34b8e2..3c340bc4df8e 100644
> --- a/arch/powerpc/include/asm/opal.h
> +++ b/arch/powerpc/include/asm/opal.h
> @@ -400,6 +400,9 @@ void opal_powercap_init(void);
> void opal_psr_init(void);
> void opal_sensor_groups_init(void);
>
> +extern int64_t opal_register_os_ops(struct opal_os_ops *os_ops);
> +extern int64_t opal_cpu_idle(__be64 srr1_addr, uint64_t psscr);
> +
> #endif /* __ASSEMBLY__ */
>
> #endif /* _ASM_POWERPC_OPAL_H */
> diff --git a/arch/powerpc/kernel/idle_book3s.S b/arch/powerpc/kernel/idle_book3s.S
> index 22f249b6f58d..8d287d1d06c0 100644
> --- a/arch/powerpc/kernel/idle_book3s.S
> +++ b/arch/powerpc/kernel/idle_book3s.S
> @@ -49,6 +49,8 @@ _GLOBAL(isa300_idle_stop_noloss)
> */
> _GLOBAL(isa300_idle_stop_mayloss)
> mtspr SPRN_PSSCR,r3
> + mr r6, r13
> + mfspr r13, SPRN_HSPRG0
> std r1,PACAR1(r13)
> mflr r4
> mfcr r5
> @@ -74,6 +76,7 @@ _GLOBAL(isa300_idle_stop_mayloss)
> std r31,-8*18(r1)
> std r4,-8*19(r1)
> std r5,-8*20(r1)
> + std r6,-8*21(r1)
> /* 168 bytes */
> PPC_STOP
> b . /* catch bugs */
> @@ -91,8 +94,10 @@ _GLOBAL(idle_return_gpr_loss)
> ld r1,PACAR1(r13)
> ld r4,-8*19(r1)
> ld r5,-8*20(r1)
> + ld r6,-8*21(r1)
> mtlr r4
> mtcr r5
> + mr r13,r6
> /*
> * KVM nap requires r2 to be saved, rather than just restoring it
> * from PACATOC. This could be avoided for that less common case
> diff --git a/arch/powerpc/platforms/powernv/idle.c b/arch/powerpc/platforms/powernv/idle.c
> index 78599bca66c2..1841027b25c5 100644
> --- a/arch/powerpc/platforms/powernv/idle.c
> +++ b/arch/powerpc/platforms/powernv/idle.c
> @@ -35,6 +35,7 @@
> static u32 supported_cpuidle_states;
> struct pnv_idle_states_t *pnv_idle_states;
> int nr_pnv_idle_states;
> +static bool firmware_stop_supported;
>
> /*
> * The default stop state that will be used by ppc_md.power_save
> @@ -602,6 +603,25 @@ struct p9_sprs {
> u64 uamor;
> };
>
> +/*
> + * This function is called from OPAL if firmware support for stop
> + * states is present and enabled. It provides a fallback for idle
> + * stop states via OPAL.
> + */
> +static uint64_t os_idle_stop(uint64_t psscr, bool save_gprs)
> +{
> + /*
> + * For lite state which does not lose even GPRS we call
> + * idle_stop_noloss while for all other states we call
> + * idle_stop_mayloss. Saving and restoration of other additional
> + * SPRs if required is handled in OPAL. All the quirks are also
> + * handled in OPAL.
> + */
> + if (!save_gprs)
> + return isa300_idle_stop_noloss(psscr);
I think PSSCR[ESL|EC] = 0 case is an overkill to go into OPAL and come
back via a callback. That can be handled in the kernel itself.
> + return isa300_idle_stop_mayloss(psscr);
> +}
> +
> static unsigned long power9_idle_stop(unsigned long psscr, bool mmu_on)
> {
> int cpu = raw_smp_processor_id();
> @@ -613,6 +633,16 @@ static unsigned long power9_idle_stop(unsigned long psscr, bool mmu_on)
> unsigned long mmcr0 = 0;
> struct p9_sprs sprs = {}; /* avoid false used-uninitialised */
> bool sprs_saved = false;
> + int rc = 0;
> +
> + /*
> + * Kernel takes decision whether to make OPAL call or not. This logic
> + * will be combined with the logic for BE opal to take decision.
> + */
> + if (firmware_stop_supported) {
> + rc = opal_cpu_idle(cpu_to_be64(__pa(&srr1)), (uint64_t) psscr);
Couple of comments here.
1) If PSSCR[ESL|EC] = 0, the current code expects mmu_on=true. When
we make an OPAL call and come back into the kernel via the
callback today, we will be in real-mode, with mmu turned off.
2) You seem to be choosing the opal cpuidle support as the default
case, and not as a fallback. Thus, with this patch you will miss
out on the deep stop-state support.
> + goto out;
> + }
>
> if (!(psscr & (PSSCR_EC|PSSCR_ESL))) {
> /* EC=ESL=0 case */
> @@ -1232,6 +1262,10 @@ static int pnv_parse_cpuidle_dt(void)
> pr_warn("opal: PowerMgmt Node not found\n");
> return -ENODEV;
> }
> +
> + if (of_device_is_compatible(np, "firmware-stop-supported"))
> + firmware_stop_supported = true;
IMO, at least for POWER9 generation, you need to do this only when
"idle-stop" device-tree cpu-feature is unavailable.
> +
> nr_idle_states = of_property_count_u32_elems(np,
> "ibm,cpu-idle-state-flags");
>
> @@ -1326,6 +1360,7 @@ static int pnv_parse_cpuidle_dt(void)
>
> static int __init pnv_init_idle_states(void)
> {
> + struct opal_os_ops os_ops;
> int cpu;
> int rc = 0;
>
> @@ -1349,6 +1384,8 @@ static int __init pnv_init_idle_states(void)
> }
> }
>
> + os_ops.os_idle_stop = be64_to_cpu(os_idle_stop);
> + rc = opal_register_os_ops((struct opal_os_ops *)(&os_ops));
> /* In case we error out nr_pnv_idle_states will be zero */
> nr_pnv_idle_states = 0;
> supported_cpuidle_states = 0;
> diff --git a/arch/powerpc/platforms/powernv/opal-call.c b/arch/powerpc/platforms/powernv/opal-call.c
> index 5cd0f52d258f..c885e607ba62 100644
> --- a/arch/powerpc/platforms/powernv/opal-call.c
> +++ b/arch/powerpc/platforms/powernv/opal-call.c
> @@ -293,3 +293,5 @@ OPAL_CALL(opal_mpipl_query_tag, OPAL_MPIPL_QUERY_TAG);
> OPAL_CALL(opal_secvar_get, OPAL_SECVAR_GET);
> OPAL_CALL(opal_secvar_get_next, OPAL_SECVAR_GET_NEXT);
> OPAL_CALL(opal_secvar_enqueue_update, OPAL_SECVAR_ENQUEUE_UPDATE);
> +OPAL_CALL(opal_register_os_ops, OPAL_REGISTER_OS_OPS);
> +OPAL_CALL(opal_cpu_idle, OPAL_CPU_IDLE);
> --
> 2.17.1
>
^ permalink raw reply
* Re: [PATCH v2] ASoC: fsl_esai: Disable exception interrupt before scheduling tasklet
From: Mark Brown @ 2020-04-27 12:06 UTC (permalink / raw)
To: festevam, Xiubo.Lee, nicoleotsuka, timur, Shengjiu Wang,
alsa-devel, tiwai, perex
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <a8f2ad955aac9e52587beedc1133b3efbe746895.1587968824.git.shengjiu.wang@nxp.com>
On Mon, 27 Apr 2020 14:23:21 +0800, Shengjiu Wang wrote:
> Disable exception interrupt before scheduling tasklet, otherwise if
> the tasklet isn't handled immediately, there will be endless xrun
> interrupt.
>
> Fixes: 7ccafa2b3879 ("ASoC: fsl_esai: recover the channel swap after xrun")
> Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
> Acked-by: Nicolin Chen <nicoleotsuka@gmail.com>
>
> [...]
Applied to
https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git for-5.7
Thanks!
[1/1] ASoC: fsl_esai: Disable exception interrupt before scheduling tasklet
commit: 1fecbb71fe0e46b886f84e3b6decca6643c3af6d
All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.
You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.
If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.
Please add any relevant lists and maintainers to the CCs when replying
to this mail.
Thanks,
Mark
^ permalink raw reply
* Re: [PATCH v2] ASoC: fsl_easrc: Check for null pointer before dereferencing "ctx" in fsl_easrc_hw_free()
From: Mark Brown @ 2020-04-27 13:09 UTC (permalink / raw)
To: perex, timur, alsa-devel, tiwai, festevam, Shengjiu Wang,
Xiubo.Lee, nicoleotsuka, lgirdwood
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <d23c939f1c9eeb3fce34b6c34d44e2d6156f663a.1587799355.git.shengjiu.wang@nxp.com>
On Sat, 25 Apr 2020 15:19:29 +0800, Shengjiu Wang wrote:
> The patch 955ac624058f: "ASoC: fsl_easrc: Add EASRC ASoC CPU DAI
> drivers" from Apr 16, 2020, leads to the following Smatch complaint:
>
> sound/soc/fsl/fsl_easrc.c:1529 fsl_easrc_hw_free()
> warn: variable dereferenced before check 'ctx' (see line 1527)
>
> sound/soc/fsl/fsl_easrc.c
> 1526 struct fsl_asrc_pair *ctx = runtime->private_data;
> 1527 struct fsl_easrc_ctx_priv *ctx_priv = ctx->private;
> ^^^^^
> Dereference
>
> [...]
Applied to
https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git for-5.8
Thanks!
[1/1] ASoC: fsl_easrc: Check for null pointer before dereferencing "ctx" in fsl_easrc_hw_free()
commit: f3fc1ea011f09156886e8f4beb240ea814f2197a
All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.
You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.
If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.
Please add any relevant lists and maintainers to the CCs when replying
to this mail.
Thanks,
Mark
^ permalink raw reply
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