[PATCH 5/5] ARM: Remove the domain switching on ARMv6k/v7 CPUs
Catalin Marinas
catalin.marinas at arm.com
Mon Mar 22 11:20:01 EDT 2010
This patch removes the domain switching functionality via the set_fs and
__switch_to functions on cores that have a TLS register.
Currently, the ioremap and vmalloc areas share the same level 1 page
tables and therefore have the same domain (DOMAIN_KERNEL). When the
kernel domain is modified from Client to Manager (via the __set_fs or in
the __switch_to function), the XN (eXecute Never) bit is overridden and
newer CPUs can speculatively prefetch the ioremap'ed memory.
Linux performs the kernel domain switching to allow user-specific
functions (copy_to/from_user, get/put_user etc.) to access kernel
memory. In order for these functions to work with the kernel domain set
to Client, the patch modifies the LDRT/STRT and related instructions to
the LDR/STR ones.
The user pages access rights are also modified for kernel read-only
access rather than read/write so that the copy-on-write mechanism still
works. CPU_USE_DOMAINS gets disabled only if HAS_TLS_REG is defined
since writing the TLS value to the high vectors page isn't possible.
The user addresses passed to the kernel are checked by the access_ok()
function so that they do not point to the kernel space.
Signed-off-by: Catalin Marinas <catalin.marinas at arm.com>
---
arch/arm/include/asm/assembler.h | 13 +++---
arch/arm/include/asm/domain.h | 31 +++++++++++++-
arch/arm/include/asm/futex.h | 9 ++--
arch/arm/include/asm/uaccess.h | 16 ++++---
arch/arm/kernel/entry-armv.S | 4 +-
arch/arm/kernel/traps.c | 17 ++++++++
arch/arm/lib/getuser.S | 13 +++---
arch/arm/lib/putuser.S | 29 +++++++------
arch/arm/lib/uaccess.S | 83 +++++++++++++++++++-------------------
arch/arm/mm/Kconfig | 8 ++++
arch/arm/mm/proc-macros.S | 7 +++
arch/arm/mm/proc-v7.S | 5 +-
12 files changed, 150 insertions(+), 85 deletions(-)
diff --git a/arch/arm/include/asm/assembler.h b/arch/arm/include/asm/assembler.h
index 00f46d9..cc84083 100644
--- a/arch/arm/include/asm/assembler.h
+++ b/arch/arm/include/asm/assembler.h
@@ -18,6 +18,7 @@
#endif
#include <asm/ptrace.h>
+#include <asm/domain.h>
/*
* Endian independent macros for shifting bytes within registers.
@@ -183,12 +184,12 @@
*/
#ifdef CONFIG_THUMB2_KERNEL
- .macro usraccoff, instr, reg, ptr, inc, off, cond, abort
+ .macro usraccoff, instr, reg, ptr, inc, off, cond, abort, t=T()
9999:
.if \inc == 1
- \instr\cond\()bt \reg, [\ptr, #\off]
+ \instr\cond\()b\()\t\().w \reg, [\ptr, #\off]
.elseif \inc == 4
- \instr\cond\()t \reg, [\ptr, #\off]
+ \instr\cond\()\t\().w \reg, [\ptr, #\off]
.else
.error "Unsupported inc macro argument"
.endif
@@ -223,13 +224,13 @@
#else /* !CONFIG_THUMB2_KERNEL */
- .macro usracc, instr, reg, ptr, inc, cond, rept, abort
+ .macro usracc, instr, reg, ptr, inc, cond, rept, abort, t=T()
.rept \rept
9999:
.if \inc == 1
- \instr\cond\()bt \reg, [\ptr], #\inc
+ \instr\cond\()b\()\t \reg, [\ptr], #\inc
.elseif \inc == 4
- \instr\cond\()t \reg, [\ptr], #\inc
+ \instr\cond\()\t \reg, [\ptr], #\inc
.else
.error "Unsupported inc macro argument"
.endif
diff --git a/arch/arm/include/asm/domain.h b/arch/arm/include/asm/domain.h
index cc7ef40..af18cea 100644
--- a/arch/arm/include/asm/domain.h
+++ b/arch/arm/include/asm/domain.h
@@ -45,13 +45,17 @@
*/
#define DOMAIN_NOACCESS 0
#define DOMAIN_CLIENT 1
+#ifdef CONFIG_CPU_USE_DOMAINS
#define DOMAIN_MANAGER 3
+#else
+#define DOMAIN_MANAGER 1
+#endif
#define domain_val(dom,type) ((type) << (2*(dom)))
#ifndef __ASSEMBLY__
-#ifdef CONFIG_MMU
+#ifdef CONFIG_CPU_USE_DOMAINS
#define set_domain(x) \
do { \
__asm__ __volatile__( \
@@ -74,5 +78,28 @@
#define modify_domain(dom,type) do { } while (0)
#endif
+/*
+ * Generate the T (user) versions of the LDR/STR and related
+ * instructions (inline assembly)
+ */
+#ifdef CONFIG_CPU_USE_DOMAINS
+#define T(instr) #instr "t"
+#else
+#define T(instr) #instr
#endif
-#endif /* !__ASSEMBLY__ */
+
+#else /* __ASSEMBLY__ */
+
+/*
+ * Generate the T (user) versions of the LDR/STR and related
+ * instructions
+ */
+#ifdef CONFIG_CPU_USE_DOMAINS
+#define T(instr) instr ## t
+#else
+#define T(instr) instr
+#endif
+
+#endif /* __ASSEMBLY__ */
+
+#endif /* !__ASM_PROC_DOMAIN_H */
diff --git a/arch/arm/include/asm/futex.h b/arch/arm/include/asm/futex.h
index bfcc159..8d868bd 100644
--- a/arch/arm/include/asm/futex.h
+++ b/arch/arm/include/asm/futex.h
@@ -13,12 +13,13 @@
#include <linux/preempt.h>
#include <linux/uaccess.h>
#include <asm/errno.h>
+#include <asm/domain.h>
#define __futex_atomic_op(insn, ret, oldval, uaddr, oparg) \
__asm__ __volatile__( \
- "1: ldrt %1, [%2]\n" \
+ "1: " T(ldr) " %1, [%2]\n" \
" " insn "\n" \
- "2: strt %0, [%2]\n" \
+ "2: " T(str) " %0, [%2]\n" \
" mov %0, #0\n" \
"3:\n" \
" .section __ex_table,\"a\"\n" \
@@ -97,10 +98,10 @@ futex_atomic_cmpxchg_inatomic(int __user *uaddr, int oldval, int newval)
pagefault_disable(); /* implies preempt_disable() */
__asm__ __volatile__("@futex_atomic_cmpxchg_inatomic\n"
- "1: ldrt %0, [%3]\n"
+ "1: " T(ldr) " %0, [%3]\n"
" teq %0, %1\n"
" it eq @ explicit IT needed for the 2b label\n"
- "2: streqt %2, [%3]\n"
+ "2: " T(streq) " %2, [%3]\n"
"3:\n"
" .section __ex_table,\"a\"\n"
" .align 3\n"
diff --git a/arch/arm/include/asm/uaccess.h b/arch/arm/include/asm/uaccess.h
index 1d6bd40..e4d0905 100644
--- a/arch/arm/include/asm/uaccess.h
+++ b/arch/arm/include/asm/uaccess.h
@@ -227,7 +227,7 @@ do { \
#define __get_user_asm_byte(x,addr,err) \
__asm__ __volatile__( \
- "1: ldrbt %1,[%2]\n" \
+ "1: " T(ldrb) " %1,[%2],#0\n" \
"2:\n" \
" .section .fixup,\"ax\"\n" \
" .align 2\n" \
@@ -263,7 +263,7 @@ do { \
#define __get_user_asm_word(x,addr,err) \
__asm__ __volatile__( \
- "1: ldrt %1,[%2]\n" \
+ "1: " T(ldr) " %1,[%2],#0\n" \
"2:\n" \
" .section .fixup,\"ax\"\n" \
" .align 2\n" \
@@ -308,7 +308,7 @@ do { \
#define __put_user_asm_byte(x,__pu_addr,err) \
__asm__ __volatile__( \
- "1: strbt %1,[%2]\n" \
+ "1: " T(strb) " %1,[%2],#0\n" \
"2:\n" \
" .section .fixup,\"ax\"\n" \
" .align 2\n" \
@@ -341,7 +341,7 @@ do { \
#define __put_user_asm_word(x,__pu_addr,err) \
__asm__ __volatile__( \
- "1: strt %1,[%2]\n" \
+ "1: " T(str) " %1,[%2],#0\n" \
"2:\n" \
" .section .fixup,\"ax\"\n" \
" .align 2\n" \
@@ -366,10 +366,10 @@ do { \
#define __put_user_asm_dword(x,__pu_addr,err) \
__asm__ __volatile__( \
- ARM( "1: strt " __reg_oper1 ", [%1], #4\n" ) \
- ARM( "2: strt " __reg_oper0 ", [%1]\n" ) \
- THUMB( "1: strt " __reg_oper1 ", [%1]\n" ) \
- THUMB( "2: strt " __reg_oper0 ", [%1, #4]\n" ) \
+ ARM( "1: " T(str) " " __reg_oper1 ", [%1], #4\n" ) \
+ ARM( "2: " T(str) " " __reg_oper0 ", [%1]\n" ) \
+ THUMB( "1: " T(str) " " __reg_oper1 ", [%1]\n" ) \
+ THUMB( "2: " T(str) " " __reg_oper0 ", [%1, #4]\n" ) \
"3:\n" \
" .section .fixup,\"ax\"\n" \
" .align 2\n" \
diff --git a/arch/arm/kernel/entry-armv.S b/arch/arm/kernel/entry-armv.S
index 6c5cf36..694f7ab 100644
--- a/arch/arm/kernel/entry-armv.S
+++ b/arch/arm/kernel/entry-armv.S
@@ -736,7 +736,7 @@ ENTRY(__switch_to)
THUMB( stmia ip!, {r4 - sl, fp} ) @ Store most regs on stack
THUMB( str sp, [ip], #4 )
THUMB( str lr, [ip], #4 )
-#ifdef CONFIG_MMU
+#ifdef CONFIG_CPU_USE_DOMAINS
ldr r6, [r2, #TI_CPU_DOMAIN]
#endif
#if defined(CONFIG_HAS_TLS_REG)
@@ -745,7 +745,7 @@ ENTRY(__switch_to)
mov r4, #0xffff0fff
str r3, [r4, #-15] @ TLS val at 0xffff0ff0
#endif
-#ifdef CONFIG_MMU
+#ifdef CONFIG_CPU_USE_DOMAINS
mcr p15, 0, r6, c3, c0, 0 @ Set domain register
#endif
mov r5, r0
diff --git a/arch/arm/kernel/traps.c b/arch/arm/kernel/traps.c
index 1621e53..6571e19 100644
--- a/arch/arm/kernel/traps.c
+++ b/arch/arm/kernel/traps.c
@@ -30,6 +30,7 @@
#include <asm/unistd.h>
#include <asm/traps.h>
#include <asm/unwind.h>
+#include <asm/tlbflush.h>
#include "ptrace.h"
#include "signal.h"
@@ -750,6 +751,16 @@ void __init early_trap_init(void)
extern char __vectors_start[], __vectors_end[];
extern char __kuser_helper_start[], __kuser_helper_end[];
int kuser_sz = __kuser_helper_end - __kuser_helper_start;
+#if !defined(CONFIG_CPU_USE_DOMAINS) && defined(CONFIG_MMU)
+ pgd_t *pgd = pgd_offset_k(vectors);
+ pmd_t *pmd = pmd_offset(pgd, vectors);
+ pte_t *pte = pte_offset_kernel(pmd, vectors);
+ pte_t entry = *pte;
+
+ /* allow writing to the vectors page */
+ set_pte_ext(pte, pte_mkwrite(entry), 0);
+ local_flush_tlb_kernel_page(vectors);
+#endif
/*
* Copy the vectors, stubs and kuser helpers (in entry-armv.S)
@@ -769,6 +780,12 @@ void __init early_trap_init(void)
memcpy((void *)KERN_RESTART_CODE, syscall_restart_code,
sizeof(syscall_restart_code));
+#if !defined(CONFIG_CPU_USE_DOMAINS) && defined(CONFIG_MMU)
+ /* restore the vectors page permissions */
+ set_pte_ext(pte, entry, 0);
+ local_flush_tlb_kernel_page(vectors);
+#endif
+
flush_icache_range(vectors, vectors + PAGE_SIZE);
modify_domain(DOMAIN_USER, DOMAIN_CLIENT);
}
diff --git a/arch/arm/lib/getuser.S b/arch/arm/lib/getuser.S
index a1814d9..acc966b 100644
--- a/arch/arm/lib/getuser.S
+++ b/arch/arm/lib/getuser.S
@@ -28,20 +28,21 @@
*/
#include <linux/linkage.h>
#include <asm/errno.h>
+#include <asm/domain.h>
ENTRY(__get_user_1)
-1: ldrbt r2, [r0]
+1: T(ldrb) r2, [r0]
mov r0, #0
mov pc, lr
ENDPROC(__get_user_1)
ENTRY(__get_user_2)
#ifdef CONFIG_THUMB2_KERNEL
-2: ldrbt r2, [r0]
-3: ldrbt r3, [r0, #1]
+2: T(ldrb) r2, [r0]
+3: T(ldrb) r3, [r0, #1]
#else
-2: ldrbt r2, [r0], #1
-3: ldrbt r3, [r0]
+2: T(ldrb) r2, [r0], #1
+3: T(ldrb) r3, [r0]
#endif
#ifndef __ARMEB__
orr r2, r2, r3, lsl #8
@@ -53,7 +54,7 @@ ENTRY(__get_user_2)
ENDPROC(__get_user_2)
ENTRY(__get_user_4)
-4: ldrt r2, [r0]
+4: T(ldr) r2, [r0]
mov r0, #0
mov pc, lr
ENDPROC(__get_user_4)
diff --git a/arch/arm/lib/putuser.S b/arch/arm/lib/putuser.S
index 02fedbf..95b3fe8 100644
--- a/arch/arm/lib/putuser.S
+++ b/arch/arm/lib/putuser.S
@@ -28,9 +28,10 @@
*/
#include <linux/linkage.h>
#include <asm/errno.h>
+#include <asm/domain.h>
ENTRY(__put_user_1)
-1: strbt r2, [r0]
+1: T(strb) r2, [r0]
mov r0, #0
mov pc, lr
ENDPROC(__put_user_1)
@@ -39,19 +40,19 @@ ENTRY(__put_user_2)
mov ip, r2, lsr #8
#ifdef CONFIG_THUMB2_KERNEL
#ifndef __ARMEB__
-2: strbt r2, [r0]
-3: strbt ip, [r0, #1]
+2: T(strb) r2, [r0]
+3: T(strb) ip, [r0, #1]
#else
-2: strbt ip, [r0]
-3: strbt r2, [r0, #1]
+2: T(strb) ip, [r0]
+3: T(strb) r2, [r0, #1]
#endif
#else /* !CONFIG_THUMB2_KERNEL */
#ifndef __ARMEB__
-2: strbt r2, [r0], #1
-3: strbt ip, [r0]
+2: T(strb) r2, [r0], #1
+3: T(strb) ip, [r0]
#else
-2: strbt ip, [r0], #1
-3: strbt r2, [r0]
+2: T(strb) ip, [r0], #1
+3: T(strb) r2, [r0]
#endif
#endif /* CONFIG_THUMB2_KERNEL */
mov r0, #0
@@ -59,18 +60,18 @@ ENTRY(__put_user_2)
ENDPROC(__put_user_2)
ENTRY(__put_user_4)
-4: strt r2, [r0]
+4: T(str) r2, [r0]
mov r0, #0
mov pc, lr
ENDPROC(__put_user_4)
ENTRY(__put_user_8)
#ifdef CONFIG_THUMB2_KERNEL
-5: strt r2, [r0]
-6: strt r3, [r0, #4]
+5: T(str) r2, [r0]
+6: T(str) r3, [r0, #4]
#else
-5: strt r2, [r0], #4
-6: strt r3, [r0]
+5: T(str) r2, [r0], #4
+6: T(str) r3, [r0]
#endif
mov r0, #0
mov pc, lr
diff --git a/arch/arm/lib/uaccess.S b/arch/arm/lib/uaccess.S
index ffdd274..e47cdfd 100644
--- a/arch/arm/lib/uaccess.S
+++ b/arch/arm/lib/uaccess.S
@@ -14,6 +14,7 @@
#include <linux/linkage.h>
#include <asm/assembler.h>
#include <asm/errno.h>
+#include <asm/domain.h>
.text
@@ -31,11 +32,11 @@
rsb ip, ip, #4
cmp ip, #2
ldrb r3, [r1], #1
-USER( strbt r3, [r0], #1) @ May fault
+USER( T(strb) r3, [r0], #1) @ May fault
ldrgeb r3, [r1], #1
-USER( strgebt r3, [r0], #1) @ May fault
+USER( T(strgeb) r3, [r0], #1) @ May fault
ldrgtb r3, [r1], #1
-USER( strgtbt r3, [r0], #1) @ May fault
+USER( T(strgtb) r3, [r0], #1) @ May fault
sub r2, r2, ip
b .Lc2u_dest_aligned
@@ -58,7 +59,7 @@ ENTRY(__copy_to_user)
addmi ip, r2, #4
bmi .Lc2u_0nowords
ldr r3, [r1], #4
-USER( strt r3, [r0], #4) @ May fault
+USER( T(str) r3, [r0], #4) @ May fault
mov ip, r0, lsl #32 - PAGE_SHIFT @ On each page, use a ld/st??t instruction
rsb ip, ip, #0
movs ip, ip, lsr #32 - PAGE_SHIFT
@@ -87,18 +88,18 @@ USER( strt r3, [r0], #4) @ May fault
stmneia r0!, {r3 - r4} @ Shouldnt fault
tst ip, #4
ldrne r3, [r1], #4
- strnet r3, [r0], #4 @ Shouldnt fault
+ T(strne) r3, [r0], #4 @ Shouldnt fault
ands ip, ip, #3
beq .Lc2u_0fupi
.Lc2u_0nowords: teq ip, #0
beq .Lc2u_finished
.Lc2u_nowords: cmp ip, #2
ldrb r3, [r1], #1
-USER( strbt r3, [r0], #1) @ May fault
+USER( T(strb) r3, [r0], #1) @ May fault
ldrgeb r3, [r1], #1
-USER( strgebt r3, [r0], #1) @ May fault
+USER( T(strgeb) r3, [r0], #1) @ May fault
ldrgtb r3, [r1], #1
-USER( strgtbt r3, [r0], #1) @ May fault
+USER( T(strgtb) r3, [r0], #1) @ May fault
b .Lc2u_finished
.Lc2u_not_enough:
@@ -119,7 +120,7 @@ USER( strgtbt r3, [r0], #1) @ May fault
mov r3, r7, pull #8
ldr r7, [r1], #4
orr r3, r3, r7, push #24
-USER( strt r3, [r0], #4) @ May fault
+USER( T(str) r3, [r0], #4) @ May fault
mov ip, r0, lsl #32 - PAGE_SHIFT
rsb ip, ip, #0
movs ip, ip, lsr #32 - PAGE_SHIFT
@@ -154,18 +155,18 @@ USER( strt r3, [r0], #4) @ May fault
movne r3, r7, pull #8
ldrne r7, [r1], #4
orrne r3, r3, r7, push #24
- strnet r3, [r0], #4 @ Shouldnt fault
+ T(strne) r3, [r0], #4 @ Shouldnt fault
ands ip, ip, #3
beq .Lc2u_1fupi
.Lc2u_1nowords: mov r3, r7, get_byte_1
teq ip, #0
beq .Lc2u_finished
cmp ip, #2
-USER( strbt r3, [r0], #1) @ May fault
+USER( T(strb) r3, [r0], #1) @ May fault
movge r3, r7, get_byte_2
-USER( strgebt r3, [r0], #1) @ May fault
+USER( T(strgeb) r3, [r0], #1) @ May fault
movgt r3, r7, get_byte_3
-USER( strgtbt r3, [r0], #1) @ May fault
+USER( T(strgtb) r3, [r0], #1) @ May fault
b .Lc2u_finished
.Lc2u_2fupi: subs r2, r2, #4
@@ -174,7 +175,7 @@ USER( strgtbt r3, [r0], #1) @ May fault
mov r3, r7, pull #16
ldr r7, [r1], #4
orr r3, r3, r7, push #16
-USER( strt r3, [r0], #4) @ May fault
+USER( T(str) r3, [r0], #4) @ May fault
mov ip, r0, lsl #32 - PAGE_SHIFT
rsb ip, ip, #0
movs ip, ip, lsr #32 - PAGE_SHIFT
@@ -209,18 +210,18 @@ USER( strt r3, [r0], #4) @ May fault
movne r3, r7, pull #16
ldrne r7, [r1], #4
orrne r3, r3, r7, push #16
- strnet r3, [r0], #4 @ Shouldnt fault
+ T(strne) r3, [r0], #4 @ Shouldnt fault
ands ip, ip, #3
beq .Lc2u_2fupi
.Lc2u_2nowords: mov r3, r7, get_byte_2
teq ip, #0
beq .Lc2u_finished
cmp ip, #2
-USER( strbt r3, [r0], #1) @ May fault
+USER( T(strb) r3, [r0], #1) @ May fault
movge r3, r7, get_byte_3
-USER( strgebt r3, [r0], #1) @ May fault
+USER( T(strgeb) r3, [r0], #1) @ May fault
ldrgtb r3, [r1], #0
-USER( strgtbt r3, [r0], #1) @ May fault
+USER( T(strgtb) r3, [r0], #1) @ May fault
b .Lc2u_finished
.Lc2u_3fupi: subs r2, r2, #4
@@ -229,7 +230,7 @@ USER( strgtbt r3, [r0], #1) @ May fault
mov r3, r7, pull #24
ldr r7, [r1], #4
orr r3, r3, r7, push #8
-USER( strt r3, [r0], #4) @ May fault
+USER( T(str) r3, [r0], #4) @ May fault
mov ip, r0, lsl #32 - PAGE_SHIFT
rsb ip, ip, #0
movs ip, ip, lsr #32 - PAGE_SHIFT
@@ -264,18 +265,18 @@ USER( strt r3, [r0], #4) @ May fault
movne r3, r7, pull #24
ldrne r7, [r1], #4
orrne r3, r3, r7, push #8
- strnet r3, [r0], #4 @ Shouldnt fault
+ T(strne) r3, [r0], #4 @ Shouldnt fault
ands ip, ip, #3
beq .Lc2u_3fupi
.Lc2u_3nowords: mov r3, r7, get_byte_3
teq ip, #0
beq .Lc2u_finished
cmp ip, #2
-USER( strbt r3, [r0], #1) @ May fault
+USER( T(strb) r3, [r0], #1) @ May fault
ldrgeb r3, [r1], #1
-USER( strgebt r3, [r0], #1) @ May fault
+USER( T(strgeb) r3, [r0], #1) @ May fault
ldrgtb r3, [r1], #0
-USER( strgtbt r3, [r0], #1) @ May fault
+USER( T(strgtb) r3, [r0], #1) @ May fault
b .Lc2u_finished
ENDPROC(__copy_to_user)
@@ -294,11 +295,11 @@ ENDPROC(__copy_to_user)
.Lcfu_dest_not_aligned:
rsb ip, ip, #4
cmp ip, #2
-USER( ldrbt r3, [r1], #1) @ May fault
+USER( T(ldrb) r3, [r1], #1) @ May fault
strb r3, [r0], #1
-USER( ldrgebt r3, [r1], #1) @ May fault
+USER( T(ldrgeb) r3, [r1], #1) @ May fault
strgeb r3, [r0], #1
-USER( ldrgtbt r3, [r1], #1) @ May fault
+USER( T(ldrgtb) r3, [r1], #1) @ May fault
strgtb r3, [r0], #1
sub r2, r2, ip
b .Lcfu_dest_aligned
@@ -321,7 +322,7 @@ ENTRY(__copy_from_user)
.Lcfu_0fupi: subs r2, r2, #4
addmi ip, r2, #4
bmi .Lcfu_0nowords
-USER( ldrt r3, [r1], #4)
+USER( T(ldr) r3, [r1], #4)
str r3, [r0], #4
mov ip, r1, lsl #32 - PAGE_SHIFT @ On each page, use a ld/st??t instruction
rsb ip, ip, #0
@@ -350,18 +351,18 @@ USER( ldrt r3, [r1], #4)
ldmneia r1!, {r3 - r4} @ Shouldnt fault
stmneia r0!, {r3 - r4}
tst ip, #4
- ldrnet r3, [r1], #4 @ Shouldnt fault
+ T(ldrne) r3, [r1], #4 @ Shouldnt fault
strne r3, [r0], #4
ands ip, ip, #3
beq .Lcfu_0fupi
.Lcfu_0nowords: teq ip, #0
beq .Lcfu_finished
.Lcfu_nowords: cmp ip, #2
-USER( ldrbt r3, [r1], #1) @ May fault
+USER( T(ldrb) r3, [r1], #1) @ May fault
strb r3, [r0], #1
-USER( ldrgebt r3, [r1], #1) @ May fault
+USER( T(ldrgeb) r3, [r1], #1) @ May fault
strgeb r3, [r0], #1
-USER( ldrgtbt r3, [r1], #1) @ May fault
+USER( T(ldrgtb) r3, [r1], #1) @ May fault
strgtb r3, [r0], #1
b .Lcfu_finished
@@ -374,7 +375,7 @@ USER( ldrgtbt r3, [r1], #1) @ May fault
.Lcfu_src_not_aligned:
bic r1, r1, #3
-USER( ldrt r7, [r1], #4) @ May fault
+USER( T(ldr) r7, [r1], #4) @ May fault
cmp ip, #2
bgt .Lcfu_3fupi
beq .Lcfu_2fupi
@@ -382,7 +383,7 @@ USER( ldrt r7, [r1], #4) @ May fault
addmi ip, r2, #4
bmi .Lcfu_1nowords
mov r3, r7, pull #8
-USER( ldrt r7, [r1], #4) @ May fault
+USER( T(ldr) r7, [r1], #4) @ May fault
orr r3, r3, r7, push #24
str r3, [r0], #4
mov ip, r1, lsl #32 - PAGE_SHIFT
@@ -417,7 +418,7 @@ USER( ldrt r7, [r1], #4) @ May fault
stmneia r0!, {r3 - r4}
tst ip, #4
movne r3, r7, pull #8
-USER( ldrnet r7, [r1], #4) @ May fault
+USER( T(ldrne) r7, [r1], #4) @ May fault
orrne r3, r3, r7, push #24
strne r3, [r0], #4
ands ip, ip, #3
@@ -437,7 +438,7 @@ USER( ldrnet r7, [r1], #4) @ May fault
addmi ip, r2, #4
bmi .Lcfu_2nowords
mov r3, r7, pull #16
-USER( ldrt r7, [r1], #4) @ May fault
+USER( T(ldr) r7, [r1], #4) @ May fault
orr r3, r3, r7, push #16
str r3, [r0], #4
mov ip, r1, lsl #32 - PAGE_SHIFT
@@ -473,7 +474,7 @@ USER( ldrt r7, [r1], #4) @ May fault
stmneia r0!, {r3 - r4}
tst ip, #4
movne r3, r7, pull #16
-USER( ldrnet r7, [r1], #4) @ May fault
+USER( T(ldrne) r7, [r1], #4) @ May fault
orrne r3, r3, r7, push #16
strne r3, [r0], #4
ands ip, ip, #3
@@ -485,7 +486,7 @@ USER( ldrnet r7, [r1], #4) @ May fault
strb r3, [r0], #1
movge r3, r7, get_byte_3
strgeb r3, [r0], #1
-USER( ldrgtbt r3, [r1], #0) @ May fault
+USER( T(ldrgtb) r3, [r1], #0) @ May fault
strgtb r3, [r0], #1
b .Lcfu_finished
@@ -493,7 +494,7 @@ USER( ldrgtbt r3, [r1], #0) @ May fault
addmi ip, r2, #4
bmi .Lcfu_3nowords
mov r3, r7, pull #24
-USER( ldrt r7, [r1], #4) @ May fault
+USER( T(ldr) r7, [r1], #4) @ May fault
orr r3, r3, r7, push #8
str r3, [r0], #4
mov ip, r1, lsl #32 - PAGE_SHIFT
@@ -528,7 +529,7 @@ USER( ldrt r7, [r1], #4) @ May fault
stmneia r0!, {r3 - r4}
tst ip, #4
movne r3, r7, pull #24
-USER( ldrnet r7, [r1], #4) @ May fault
+USER( T(ldrne) r7, [r1], #4) @ May fault
orrne r3, r3, r7, push #8
strne r3, [r0], #4
ands ip, ip, #3
@@ -538,9 +539,9 @@ USER( ldrnet r7, [r1], #4) @ May fault
beq .Lcfu_finished
cmp ip, #2
strb r3, [r0], #1
-USER( ldrgebt r3, [r1], #1) @ May fault
+USER( T(ldrgeb) r3, [r1], #1) @ May fault
strgeb r3, [r0], #1
-USER( ldrgtbt r3, [r1], #1) @ May fault
+USER( T(ldrgtb) r3, [r1], #1) @ May fault
strgtb r3, [r0], #1
b .Lcfu_finished
ENDPROC(__copy_from_user)
diff --git a/arch/arm/mm/Kconfig b/arch/arm/mm/Kconfig
index 5df74c1..755e081 100644
--- a/arch/arm/mm/Kconfig
+++ b/arch/arm/mm/Kconfig
@@ -597,6 +597,14 @@ config CPU_CP15_MPU
help
Processor has the CP15 register, which has MPU related registers.
+config CPU_USE_DOMAINS
+ bool
+ depends on MMU
+ default y if !HAS_TLS_REG
+ help
+ This option enables or disables the use of domain switching
+ via the set_fs() function.
+
#
# CPU supports 36-bit I/O
#
diff --git a/arch/arm/mm/proc-macros.S b/arch/arm/mm/proc-macros.S
index 7d63bea..337f102 100644
--- a/arch/arm/mm/proc-macros.S
+++ b/arch/arm/mm/proc-macros.S
@@ -99,6 +99,10 @@
* 110x 0 1 0 r/w r/o
* 11x0 0 1 0 r/w r/o
* 1111 0 1 1 r/w r/w
+ *
+ * If !CONFIG_CPU_USE_DOMAINS, the following permissions are changed:
+ * 110x 1 1 1 r/o r/o
+ * 11x0 1 1 1 r/o r/o
*/
.macro armv6_mt_table pfx
\pfx\()_mt_table:
@@ -138,8 +142,11 @@
tst r1, #L_PTE_USER
orrne r3, r3, #PTE_EXT_AP1
+#ifdef CONFIG_CPU_USE_DOMAINS
+ @ allow kernel read/write access to read-only user pages
tstne r3, #PTE_EXT_APX
bicne r3, r3, #PTE_EXT_APX | PTE_EXT_AP0
+#endif
tst r1, #L_PTE_EXEC
orreq r3, r3, #PTE_EXT_XN
diff --git a/arch/arm/mm/proc-v7.S b/arch/arm/mm/proc-v7.S
index 7aaf88a..c1c3fe0 100644
--- a/arch/arm/mm/proc-v7.S
+++ b/arch/arm/mm/proc-v7.S
@@ -152,8 +152,11 @@ ENTRY(cpu_v7_set_pte_ext)
tst r1, #L_PTE_USER
orrne r3, r3, #PTE_EXT_AP1
+#ifdef CONFIG_CPU_USE_DOMAINS
+ @ allow kernel read/write access to read-only user pages
tstne r3, #PTE_EXT_APX
bicne r3, r3, #PTE_EXT_APX | PTE_EXT_AP0
+#endif
tst r1, #L_PTE_EXEC
orreq r3, r3, #PTE_EXT_XN
@@ -240,8 +243,6 @@ __v7_setup:
mcr p15, 0, r10, c2, c0, 2 @ TTB control register
orr r4, r4, #TTB_FLAGS
mcr p15, 0, r4, c2, c0, 1 @ load TTB1
- mov r10, #0x1f @ domains 0, 1 = manager
- mcr p15, 0, r10, c3, c0, 0 @ load domain access register
/*
* Memory region attributes with SCTLR.TRE=1
*
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