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authorCatalin Marinas <catalin.marinas@arm.com>2010-09-13 11:03:21 -0400
committerRussell King <rmk+kernel@arm.linux.org.uk>2010-11-04 11:44:31 -0400
commit247055aa21ffef1c49dd64710d5e94c2aee19b58 (patch)
treee9e026b96597d080de4c16bb88c17b0495c61904 /arch/arm/lib/uaccess.S
parentff8b16d7e15a8ba2a6086645614a483e048e3fbf (diff)
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 <cbouatmailru@gmail.com> Cc: Tony Lindgren <tony@atomide.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm/lib/uaccess.S')
-rw-r--r--arch/arm/lib/uaccess.S83
1 files changed, 42 insertions, 41 deletions
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 @@
14#include <linux/linkage.h> 14#include <linux/linkage.h>
15#include <asm/assembler.h> 15#include <asm/assembler.h>
16#include <asm/errno.h> 16#include <asm/errno.h>
17#include <asm/domain.h>
17 18
18 .text 19 .text
19 20
@@ -31,11 +32,11 @@
31 rsb ip, ip, #4 32 rsb ip, ip, #4
32 cmp ip, #2 33 cmp ip, #2
33 ldrb r3, [r1], #1 34 ldrb r3, [r1], #1
34USER( strbt r3, [r0], #1) @ May fault 35USER( T(strb) r3, [r0], #1) @ May fault
35 ldrgeb r3, [r1], #1 36 ldrgeb r3, [r1], #1
36USER( strgebt r3, [r0], #1) @ May fault 37USER( T(strgeb) r3, [r0], #1) @ May fault
37 ldrgtb r3, [r1], #1 38 ldrgtb r3, [r1], #1
38USER( strgtbt r3, [r0], #1) @ May fault 39USER( T(strgtb) r3, [r0], #1) @ May fault
39 sub r2, r2, ip 40 sub r2, r2, ip
40 b .Lc2u_dest_aligned 41 b .Lc2u_dest_aligned
41 42
@@ -58,7 +59,7 @@ ENTRY(__copy_to_user)
58 addmi ip, r2, #4 59 addmi ip, r2, #4
59 bmi .Lc2u_0nowords 60 bmi .Lc2u_0nowords
60 ldr r3, [r1], #4 61 ldr r3, [r1], #4
61USER( strt r3, [r0], #4) @ May fault 62USER( T(str) r3, [r0], #4) @ May fault
62 mov ip, r0, lsl #32 - PAGE_SHIFT @ On each page, use a ld/st??t instruction 63 mov ip, r0, lsl #32 - PAGE_SHIFT @ On each page, use a ld/st??t instruction
63 rsb ip, ip, #0 64 rsb ip, ip, #0
64 movs ip, ip, lsr #32 - PAGE_SHIFT 65 movs ip, ip, lsr #32 - PAGE_SHIFT
@@ -87,18 +88,18 @@ USER( strt r3, [r0], #4) @ May fault
87 stmneia r0!, {r3 - r4} @ Shouldnt fault 88 stmneia r0!, {r3 - r4} @ Shouldnt fault
88 tst ip, #4 89 tst ip, #4
89 ldrne r3, [r1], #4 90 ldrne r3, [r1], #4
90 strnet r3, [r0], #4 @ Shouldnt fault 91 T(strne) r3, [r0], #4 @ Shouldnt fault
91 ands ip, ip, #3 92 ands ip, ip, #3
92 beq .Lc2u_0fupi 93 beq .Lc2u_0fupi
93.Lc2u_0nowords: teq ip, #0 94.Lc2u_0nowords: teq ip, #0
94 beq .Lc2u_finished 95 beq .Lc2u_finished
95.Lc2u_nowords: cmp ip, #2 96.Lc2u_nowords: cmp ip, #2
96 ldrb r3, [r1], #1 97 ldrb r3, [r1], #1
97USER( strbt r3, [r0], #1) @ May fault 98USER( T(strb) r3, [r0], #1) @ May fault
98 ldrgeb r3, [r1], #1 99 ldrgeb r3, [r1], #1
99USER( strgebt r3, [r0], #1) @ May fault 100USER( T(strgeb) r3, [r0], #1) @ May fault
100 ldrgtb r3, [r1], #1 101 ldrgtb r3, [r1], #1
101USER( strgtbt r3, [r0], #1) @ May fault 102USER( T(strgtb) r3, [r0], #1) @ May fault
102 b .Lc2u_finished 103 b .Lc2u_finished
103 104
104.Lc2u_not_enough: 105.Lc2u_not_enough:
@@ -119,7 +120,7 @@ USER( strgtbt r3, [r0], #1) @ May fault
119 mov r3, r7, pull #8 120 mov r3, r7, pull #8
120 ldr r7, [r1], #4 121 ldr r7, [r1], #4
121 orr r3, r3, r7, push #24 122 orr r3, r3, r7, push #24
122USER( strt r3, [r0], #4) @ May fault 123USER( T(str) r3, [r0], #4) @ May fault
123 mov ip, r0, lsl #32 - PAGE_SHIFT 124 mov ip, r0, lsl #32 - PAGE_SHIFT
124 rsb ip, ip, #0 125 rsb ip, ip, #0
125 movs ip, ip, lsr #32 - PAGE_SHIFT 126 movs ip, ip, lsr #32 - PAGE_SHIFT
@@ -154,18 +155,18 @@ USER( strt r3, [r0], #4) @ May fault
154 movne r3, r7, pull #8 155 movne r3, r7, pull #8
155 ldrne r7, [r1], #4 156 ldrne r7, [r1], #4
156 orrne r3, r3, r7, push #24 157 orrne r3, r3, r7, push #24
157 strnet r3, [r0], #4 @ Shouldnt fault 158 T(strne) r3, [r0], #4 @ Shouldnt fault
158 ands ip, ip, #3 159 ands ip, ip, #3
159 beq .Lc2u_1fupi 160 beq .Lc2u_1fupi
160.Lc2u_1nowords: mov r3, r7, get_byte_1 161.Lc2u_1nowords: mov r3, r7, get_byte_1
161 teq ip, #0 162 teq ip, #0
162 beq .Lc2u_finished 163 beq .Lc2u_finished
163 cmp ip, #2 164 cmp ip, #2
164USER( strbt r3, [r0], #1) @ May fault 165USER( T(strb) r3, [r0], #1) @ May fault
165 movge r3, r7, get_byte_2 166 movge r3, r7, get_byte_2
166USER( strgebt r3, [r0], #1) @ May fault 167USER( T(strgeb) r3, [r0], #1) @ May fault
167 movgt r3, r7, get_byte_3 168 movgt r3, r7, get_byte_3
168USER( strgtbt r3, [r0], #1) @ May fault 169USER( T(strgtb) r3, [r0], #1) @ May fault
169 b .Lc2u_finished 170 b .Lc2u_finished
170 171
171.Lc2u_2fupi: subs r2, r2, #4 172.Lc2u_2fupi: subs r2, r2, #4
@@ -174,7 +175,7 @@ USER( strgtbt r3, [r0], #1) @ May fault
174 mov r3, r7, pull #16 175 mov r3, r7, pull #16
175 ldr r7, [r1], #4 176 ldr r7, [r1], #4
176 orr r3, r3, r7, push #16 177 orr r3, r3, r7, push #16
177USER( strt r3, [r0], #4) @ May fault 178USER( T(str) r3, [r0], #4) @ May fault
178 mov ip, r0, lsl #32 - PAGE_SHIFT 179 mov ip, r0, lsl #32 - PAGE_SHIFT
179 rsb ip, ip, #0 180 rsb ip, ip, #0
180 movs ip, ip, lsr #32 - PAGE_SHIFT 181 movs ip, ip, lsr #32 - PAGE_SHIFT
@@ -209,18 +210,18 @@ USER( strt r3, [r0], #4) @ May fault
209 movne r3, r7, pull #16 210 movne r3, r7, pull #16
210 ldrne r7, [r1], #4 211 ldrne r7, [r1], #4
211 orrne r3, r3, r7, push #16 212 orrne r3, r3, r7, push #16
212 strnet r3, [r0], #4 @ Shouldnt fault 213 T(strne) r3, [r0], #4 @ Shouldnt fault
213 ands ip, ip, #3 214 ands ip, ip, #3
214 beq .Lc2u_2fupi 215 beq .Lc2u_2fupi
215.Lc2u_2nowords: mov r3, r7, get_byte_2 216.Lc2u_2nowords: mov r3, r7, get_byte_2
216 teq ip, #0 217 teq ip, #0
217 beq .Lc2u_finished 218 beq .Lc2u_finished
218 cmp ip, #2 219 cmp ip, #2
219USER( strbt r3, [r0], #1) @ May fault 220USER( T(strb) r3, [r0], #1) @ May fault
220 movge r3, r7, get_byte_3 221 movge r3, r7, get_byte_3
221USER( strgebt r3, [r0], #1) @ May fault 222USER( T(strgeb) r3, [r0], #1) @ May fault
222 ldrgtb r3, [r1], #0 223 ldrgtb r3, [r1], #0
223USER( strgtbt r3, [r0], #1) @ May fault 224USER( T(strgtb) r3, [r0], #1) @ May fault
224 b .Lc2u_finished 225 b .Lc2u_finished
225 226
226.Lc2u_3fupi: subs r2, r2, #4 227.Lc2u_3fupi: subs r2, r2, #4
@@ -229,7 +230,7 @@ USER( strgtbt r3, [r0], #1) @ May fault
229 mov r3, r7, pull #24 230 mov r3, r7, pull #24
230 ldr r7, [r1], #4 231 ldr r7, [r1], #4
231 orr r3, r3, r7, push #8 232 orr r3, r3, r7, push #8
232USER( strt r3, [r0], #4) @ May fault 233USER( T(str) r3, [r0], #4) @ May fault
233 mov ip, r0, lsl #32 - PAGE_SHIFT 234 mov ip, r0, lsl #32 - PAGE_SHIFT
234 rsb ip, ip, #0 235 rsb ip, ip, #0
235 movs ip, ip, lsr #32 - PAGE_SHIFT 236 movs ip, ip, lsr #32 - PAGE_SHIFT
@@ -264,18 +265,18 @@ USER( strt r3, [r0], #4) @ May fault
264 movne r3, r7, pull #24 265 movne r3, r7, pull #24
265 ldrne r7, [r1], #4 266 ldrne r7, [r1], #4
266 orrne r3, r3, r7, push #8 267 orrne r3, r3, r7, push #8
267 strnet r3, [r0], #4 @ Shouldnt fault 268 T(strne) r3, [r0], #4 @ Shouldnt fault
268 ands ip, ip, #3 269 ands ip, ip, #3
269 beq .Lc2u_3fupi 270 beq .Lc2u_3fupi
270.Lc2u_3nowords: mov r3, r7, get_byte_3 271.Lc2u_3nowords: mov r3, r7, get_byte_3
271 teq ip, #0 272 teq ip, #0
272 beq .Lc2u_finished 273 beq .Lc2u_finished
273 cmp ip, #2 274 cmp ip, #2
274USER( strbt r3, [r0], #1) @ May fault 275USER( T(strb) r3, [r0], #1) @ May fault
275 ldrgeb r3, [r1], #1 276 ldrgeb r3, [r1], #1
276USER( strgebt r3, [r0], #1) @ May fault 277USER( T(strgeb) r3, [r0], #1) @ May fault
277 ldrgtb r3, [r1], #0 278 ldrgtb r3, [r1], #0
278USER( strgtbt r3, [r0], #1) @ May fault 279USER( T(strgtb) r3, [r0], #1) @ May fault
279 b .Lc2u_finished 280 b .Lc2u_finished
280ENDPROC(__copy_to_user) 281ENDPROC(__copy_to_user)
281 282
@@ -294,11 +295,11 @@ ENDPROC(__copy_to_user)
294.Lcfu_dest_not_aligned: 295.Lcfu_dest_not_aligned:
295 rsb ip, ip, #4 296 rsb ip, ip, #4
296 cmp ip, #2 297 cmp ip, #2
297USER( ldrbt r3, [r1], #1) @ May fault 298USER( T(ldrb) r3, [r1], #1) @ May fault
298 strb r3, [r0], #1 299 strb r3, [r0], #1
299USER( ldrgebt r3, [r1], #1) @ May fault 300USER( T(ldrgeb) r3, [r1], #1) @ May fault
300 strgeb r3, [r0], #1 301 strgeb r3, [r0], #1
301USER( ldrgtbt r3, [r1], #1) @ May fault 302USER( T(ldrgtb) r3, [r1], #1) @ May fault
302 strgtb r3, [r0], #1 303 strgtb r3, [r0], #1
303 sub r2, r2, ip 304 sub r2, r2, ip
304 b .Lcfu_dest_aligned 305 b .Lcfu_dest_aligned
@@ -321,7 +322,7 @@ ENTRY(__copy_from_user)
321.Lcfu_0fupi: subs r2, r2, #4 322.Lcfu_0fupi: subs r2, r2, #4
322 addmi ip, r2, #4 323 addmi ip, r2, #4
323 bmi .Lcfu_0nowords 324 bmi .Lcfu_0nowords
324USER( ldrt r3, [r1], #4) 325USER( T(ldr) r3, [r1], #4)
325 str r3, [r0], #4 326 str r3, [r0], #4
326 mov ip, r1, lsl #32 - PAGE_SHIFT @ On each page, use a ld/st??t instruction 327 mov ip, r1, lsl #32 - PAGE_SHIFT @ On each page, use a ld/st??t instruction
327 rsb ip, ip, #0 328 rsb ip, ip, #0
@@ -350,18 +351,18 @@ USER( ldrt r3, [r1], #4)
350 ldmneia r1!, {r3 - r4} @ Shouldnt fault 351 ldmneia r1!, {r3 - r4} @ Shouldnt fault
351 stmneia r0!, {r3 - r4} 352 stmneia r0!, {r3 - r4}
352 tst ip, #4 353 tst ip, #4
353 ldrnet r3, [r1], #4 @ Shouldnt fault 354 T(ldrne) r3, [r1], #4 @ Shouldnt fault
354 strne r3, [r0], #4 355 strne r3, [r0], #4
355 ands ip, ip, #3 356 ands ip, ip, #3
356 beq .Lcfu_0fupi 357 beq .Lcfu_0fupi
357.Lcfu_0nowords: teq ip, #0 358.Lcfu_0nowords: teq ip, #0
358 beq .Lcfu_finished 359 beq .Lcfu_finished
359.Lcfu_nowords: cmp ip, #2 360.Lcfu_nowords: cmp ip, #2
360USER( ldrbt r3, [r1], #1) @ May fault 361USER( T(ldrb) r3, [r1], #1) @ May fault
361 strb r3, [r0], #1 362 strb r3, [r0], #1
362USER( ldrgebt r3, [r1], #1) @ May fault 363USER( T(ldrgeb) r3, [r1], #1) @ May fault
363 strgeb r3, [r0], #1 364 strgeb r3, [r0], #1
364USER( ldrgtbt r3, [r1], #1) @ May fault 365USER( T(ldrgtb) r3, [r1], #1) @ May fault
365 strgtb r3, [r0], #1 366 strgtb r3, [r0], #1
366 b .Lcfu_finished 367 b .Lcfu_finished
367 368
@@ -374,7 +375,7 @@ USER( ldrgtbt r3, [r1], #1) @ May fault
374 375
375.Lcfu_src_not_aligned: 376.Lcfu_src_not_aligned:
376 bic r1, r1, #3 377 bic r1, r1, #3
377USER( ldrt r7, [r1], #4) @ May fault 378USER( T(ldr) r7, [r1], #4) @ May fault
378 cmp ip, #2 379 cmp ip, #2
379 bgt .Lcfu_3fupi 380 bgt .Lcfu_3fupi
380 beq .Lcfu_2fupi 381 beq .Lcfu_2fupi
@@ -382,7 +383,7 @@ USER( ldrt r7, [r1], #4) @ May fault
382 addmi ip, r2, #4 383 addmi ip, r2, #4
383 bmi .Lcfu_1nowords 384 bmi .Lcfu_1nowords
384 mov r3, r7, pull #8 385 mov r3, r7, pull #8
385USER( ldrt r7, [r1], #4) @ May fault 386USER( T(ldr) r7, [r1], #4) @ May fault
386 orr r3, r3, r7, push #24 387 orr r3, r3, r7, push #24
387 str r3, [r0], #4 388 str r3, [r0], #4
388 mov ip, r1, lsl #32 - PAGE_SHIFT 389 mov ip, r1, lsl #32 - PAGE_SHIFT
@@ -417,7 +418,7 @@ USER( ldrt r7, [r1], #4) @ May fault
417 stmneia r0!, {r3 - r4} 418 stmneia r0!, {r3 - r4}
418 tst ip, #4 419 tst ip, #4
419 movne r3, r7, pull #8 420 movne r3, r7, pull #8
420USER( ldrnet r7, [r1], #4) @ May fault 421USER( T(ldrne) r7, [r1], #4) @ May fault
421 orrne r3, r3, r7, push #24 422 orrne r3, r3, r7, push #24
422 strne r3, [r0], #4 423 strne r3, [r0], #4
423 ands ip, ip, #3 424 ands ip, ip, #3
@@ -437,7 +438,7 @@ USER( ldrnet r7, [r1], #4) @ May fault
437 addmi ip, r2, #4 438 addmi ip, r2, #4
438 bmi .Lcfu_2nowords 439 bmi .Lcfu_2nowords
439 mov r3, r7, pull #16 440 mov r3, r7, pull #16
440USER( ldrt r7, [r1], #4) @ May fault 441USER( T(ldr) r7, [r1], #4) @ May fault
441 orr r3, r3, r7, push #16 442 orr r3, r3, r7, push #16
442 str r3, [r0], #4 443 str r3, [r0], #4
443 mov ip, r1, lsl #32 - PAGE_SHIFT 444 mov ip, r1, lsl #32 - PAGE_SHIFT
@@ -473,7 +474,7 @@ USER( ldrt r7, [r1], #4) @ May fault
473 stmneia r0!, {r3 - r4} 474 stmneia r0!, {r3 - r4}
474 tst ip, #4 475 tst ip, #4
475 movne r3, r7, pull #16 476 movne r3, r7, pull #16
476USER( ldrnet r7, [r1], #4) @ May fault 477USER( T(ldrne) r7, [r1], #4) @ May fault
477 orrne r3, r3, r7, push #16 478 orrne r3, r3, r7, push #16
478 strne r3, [r0], #4 479 strne r3, [r0], #4
479 ands ip, ip, #3 480 ands ip, ip, #3
@@ -485,7 +486,7 @@ USER( ldrnet r7, [r1], #4) @ May fault
485 strb r3, [r0], #1 486 strb r3, [r0], #1
486 movge r3, r7, get_byte_3 487 movge r3, r7, get_byte_3
487 strgeb r3, [r0], #1 488 strgeb r3, [r0], #1
488USER( ldrgtbt r3, [r1], #0) @ May fault 489USER( T(ldrgtb) r3, [r1], #0) @ May fault
489 strgtb r3, [r0], #1 490 strgtb r3, [r0], #1
490 b .Lcfu_finished 491 b .Lcfu_finished
491 492
@@ -493,7 +494,7 @@ USER( ldrgtbt r3, [r1], #0) @ May fault
493 addmi ip, r2, #4 494 addmi ip, r2, #4
494 bmi .Lcfu_3nowords 495 bmi .Lcfu_3nowords
495 mov r3, r7, pull #24 496 mov r3, r7, pull #24
496USER( ldrt r7, [r1], #4) @ May fault 497USER( T(ldr) r7, [r1], #4) @ May fault
497 orr r3, r3, r7, push #8 498 orr r3, r3, r7, push #8
498 str r3, [r0], #4 499 str r3, [r0], #4
499 mov ip, r1, lsl #32 - PAGE_SHIFT 500 mov ip, r1, lsl #32 - PAGE_SHIFT
@@ -528,7 +529,7 @@ USER( ldrt r7, [r1], #4) @ May fault
528 stmneia r0!, {r3 - r4} 529 stmneia r0!, {r3 - r4}
529 tst ip, #4 530 tst ip, #4
530 movne r3, r7, pull #24 531 movne r3, r7, pull #24
531USER( ldrnet r7, [r1], #4) @ May fault 532USER( T(ldrne) r7, [r1], #4) @ May fault
532 orrne r3, r3, r7, push #8 533 orrne r3, r3, r7, push #8
533 strne r3, [r0], #4 534 strne r3, [r0], #4
534 ands ip, ip, #3 535 ands ip, ip, #3
@@ -538,9 +539,9 @@ USER( ldrnet r7, [r1], #4) @ May fault
538 beq .Lcfu_finished 539 beq .Lcfu_finished
539 cmp ip, #2 540 cmp ip, #2
540 strb r3, [r0], #1 541 strb r3, [r0], #1
541USER( ldrgebt r3, [r1], #1) @ May fault 542USER( T(ldrgeb) r3, [r1], #1) @ May fault
542 strgeb r3, [r0], #1 543 strgeb r3, [r0], #1
543USER( ldrgtbt r3, [r1], #1) @ May fault 544USER( T(ldrgtb) r3, [r1], #1) @ May fault
544 strgtb r3, [r0], #1 545 strgtb r3, [r0], #1
545 b .Lcfu_finished 546 b .Lcfu_finished
546ENDPROC(__copy_from_user) 547ENDPROC(__copy_from_user)
generated by cgit v1.2.2 (git 2.25.0) at 2024-12-26 00:02:42 -0500