From 247055aa21ffef1c49dd64710d5e94c2aee19b58 Mon Sep 17 00:00:00 2001 From: Catalin Marinas Date: Mon, 13 Sep 2010 16:03:21 +0100 Subject: ARM: 6384/1: Remove the domain switching on ARMv6k/v7 CPUs 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 the hardware has a TLS register (CPU_32v6K 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. Tested-by: Anton Vorontsov Cc: Tony Lindgren Signed-off-by: Catalin Marinas Signed-off-by: Russell King --- arch/arm/lib/getuser.S | 13 ++++---- arch/arm/lib/putuser.S | 29 +++++++++--------- arch/arm/lib/uaccess.S | 83 +++++++++++++++++++++++++------------------------- 3 files changed, 64 insertions(+), 61 deletions(-) (limited to 'arch/arm/lib') diff --git a/arch/arm/lib/getuser.S b/arch/arm/lib/getuser.S index b1631a7dbe7..1b049cd7a49 100644 --- a/arch/arm/lib/getuser.S +++ b/arch/arm/lib/getuser.S @@ -28,20 +28,21 @@ */ #include #include +#include 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 5a01a23c6c0..c023fc11e86 100644 --- a/arch/arm/lib/putuser.S +++ b/arch/arm/lib/putuser.S @@ -28,9 +28,10 @@ */ #include #include +#include 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 fee9f6f88ad..d0ece2aeb70 100644 --- a/arch/arm/lib/uaccess.S +++ b/arch/arm/lib/uaccess.S @@ -14,6 +14,7 @@ #include #include #include +#include .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) -- cgit v1.2.3-70-g09d2