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ARM: entry: data abort: ensure r5 is preserved by abort functions
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Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Russell King committed Jul 2, 2011
1 parent 108f6af commit 40f0b90
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Showing 2 changed files with 38 additions and 43 deletions.
48 changes: 22 additions & 26 deletions arch/arm/mm/abort-lv4t.S
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Original file line number Diff line number Diff line change
Expand Up @@ -7,11 +7,7 @@
* : r4 = aborted context pc
* : r5 = aborted context psr
*
* Returns : r0 = address of abort
* : r1 = FSR, bit 11 = write
* : r2-r8 = corrupted
* : r9 = preserved
* : sp = pointer to registers
* Returns : r4-r5, r10-r11, r13 preserved
*
* Purpose : obtain information about current aborted instruction.
* Note: we read user space. This means we might cause a data
Expand Down Expand Up @@ -72,30 +68,30 @@ ENTRY(v4t_late_abort)
add r6, r6, r6, lsr #8
add r6, r6, r6, lsr #4
and r6, r6, #15 @ r6 = no. of registers to transfer.
and r5, r8, #15 << 16 @ Extract 'n' from instruction
ldr r7, [r2, r5, lsr #14] @ Get register 'Rn'
and r9, r8, #15 << 16 @ Extract 'n' from instruction
ldr r7, [r2, r9, lsr #14] @ Get register 'Rn'
tst r8, #1 << 23 @ Check U bit
subne r7, r7, r6, lsl #2 @ Undo increment
addeq r7, r7, r6, lsl #2 @ Undo decrement
str r7, [r2, r5, lsr #14] @ Put register 'Rn'
str r7, [r2, r9, lsr #14] @ Put register 'Rn'
b do_DataAbort

.data_arm_lateldrhpre:
tst r8, #1 << 21 @ Check writeback bit
beq do_DataAbort @ No writeback -> no fixup
.data_arm_lateldrhpost:
and r5, r8, #0x00f @ get Rm / low nibble of immediate value
and r9, r8, #0x00f @ get Rm / low nibble of immediate value
tst r8, #1 << 22 @ if (immediate offset)
andne r6, r8, #0xf00 @ { immediate high nibble
orrne r6, r5, r6, lsr #4 @ combine nibbles } else
ldreq r6, [r2, r5, lsl #2] @ { load Rm value }
orrne r6, r9, r6, lsr #4 @ combine nibbles } else
ldreq r6, [r2, r9, lsl #2] @ { load Rm value }
.data_arm_apply_r6_and_rn:
and r5, r8, #15 << 16 @ Extract 'n' from instruction
ldr r7, [r2, r5, lsr #14] @ Get register 'Rn'
and r9, r8, #15 << 16 @ Extract 'n' from instruction
ldr r7, [r2, r9, lsr #14] @ Get register 'Rn'
tst r8, #1 << 23 @ Check U bit
subne r7, r7, r6 @ Undo incrmenet
addeq r7, r7, r6 @ Undo decrement
str r7, [r2, r5, lsr #14] @ Put register 'Rn'
str r7, [r2, r9, lsr #14] @ Put register 'Rn'
b do_DataAbort

.data_arm_lateldrpreconst:
Expand All @@ -104,12 +100,12 @@ ENTRY(v4t_late_abort)
.data_arm_lateldrpostconst:
movs r6, r8, lsl #20 @ Get offset
beq do_DataAbort @ zero -> no fixup
and r5, r8, #15 << 16 @ Extract 'n' from instruction
ldr r7, [r2, r5, lsr #14] @ Get register 'Rn'
and r9, r8, #15 << 16 @ Extract 'n' from instruction
ldr r7, [r2, r9, lsr #14] @ Get register 'Rn'
tst r8, #1 << 23 @ Check U bit
subne r7, r7, r6, lsr #20 @ Undo increment
addeq r7, r7, r6, lsr #20 @ Undo decrement
str r7, [r2, r5, lsr #14] @ Put register 'Rn'
str r7, [r2, r9, lsr #14] @ Put register 'Rn'
b do_DataAbort

.data_arm_lateldrprereg:
Expand All @@ -118,38 +114,38 @@ ENTRY(v4t_late_abort)
.data_arm_lateldrpostreg:
and r7, r8, #15 @ Extract 'm' from instruction
ldr r6, [r2, r7, lsl #2] @ Get register 'Rm'
mov r5, r8, lsr #7 @ get shift count
ands r5, r5, #31
mov r9, r8, lsr #7 @ get shift count
ands r9, r9, #31
and r7, r8, #0x70 @ get shift type
orreq r7, r7, #8 @ shift count = 0
add pc, pc, r7
nop

mov r6, r6, lsl r5 @ 0: LSL #!0
mov r6, r6, lsl r9 @ 0: LSL #!0
b .data_arm_apply_r6_and_rn
b .data_arm_apply_r6_and_rn @ 1: LSL #0
nop
b .data_unknown @ 2: MUL?
nop
b .data_unknown @ 3: MUL?
nop
mov r6, r6, lsr r5 @ 4: LSR #!0
mov r6, r6, lsr r9 @ 4: LSR #!0
b .data_arm_apply_r6_and_rn
mov r6, r6, lsr #32 @ 5: LSR #32
b .data_arm_apply_r6_and_rn
b .data_unknown @ 6: MUL?
nop
b .data_unknown @ 7: MUL?
nop
mov r6, r6, asr r5 @ 8: ASR #!0
mov r6, r6, asr r9 @ 8: ASR #!0
b .data_arm_apply_r6_and_rn
mov r6, r6, asr #32 @ 9: ASR #32
b .data_arm_apply_r6_and_rn
b .data_unknown @ A: MUL?
nop
b .data_unknown @ B: MUL?
nop
mov r6, r6, ror r5 @ C: ROR #!0
mov r6, r6, ror r9 @ C: ROR #!0
b .data_arm_apply_r6_and_rn
mov r6, r6, rrx @ D: RRX
b .data_arm_apply_r6_and_rn
Expand Down Expand Up @@ -216,9 +212,9 @@ ENTRY(v4t_late_abort)
and r6, r6, #0x33
add r6, r6, r9, lsr #2
add r6, r6, r6, lsr #4
and r5, r8, #7 << 8
ldr r7, [r2, r5, lsr #6]
and r9, r8, #7 << 8
ldr r7, [r2, r9, lsr #6]
and r6, r6, #15 @ number of regs to transfer
sub r7, r7, r6, lsl #2 @ always decrement
str r7, [r2, r5, lsr #6]
str r7, [r2, r9, lsr #6]
b do_DataAbort
33 changes: 16 additions & 17 deletions arch/arm/mm/proc-arm6_7.S
View file
Original file line number Diff line number Diff line change
Expand Up @@ -35,8 +35,7 @@ ENTRY(cpu_arm7_dcache_clean_area)
*
* Purpose : obtain information about current aborted instruction
*
* Returns : r0 = address of abort
* : r1 = FSR
* Returns : r4-r5, r10-r11, r13 preserved
*/

ENTRY(cpu_arm7_data_abort)
Expand Down Expand Up @@ -95,21 +94,21 @@ ENTRY(cpu_arm6_data_abort)
add r6, r6, r6, lsr #8
add r6, r6, r6, lsr #4
and r6, r6, #15 @ r6 = no. of registers to transfer.
and r5, r8, #15 << 16 @ Extract 'n' from instruction
ldr r7, [r2, r5, lsr #14] @ Get register 'Rn'
and r9, r8, #15 << 16 @ Extract 'n' from instruction
ldr r7, [r2, r9, lsr #14] @ Get register 'Rn'
tst r8, #1 << 23 @ Check U bit
subne r7, r7, r6, lsl #2 @ Undo increment
addeq r7, r7, r6, lsl #2 @ Undo decrement
str r7, [r2, r5, lsr #14] @ Put register 'Rn'
str r7, [r2, r9, lsr #14] @ Put register 'Rn'
b do_DataAbort

.data_arm_apply_r6_and_rn:
and r5, r8, #15 << 16 @ Extract 'n' from instruction
ldr r7, [r2, r5, lsr #14] @ Get register 'Rn'
and r9, r8, #15 << 16 @ Extract 'n' from instruction
ldr r7, [r2, r9, lsr #14] @ Get register 'Rn'
tst r8, #1 << 23 @ Check U bit
subne r7, r7, r6 @ Undo incrmenet
addeq r7, r7, r6 @ Undo decrement
str r7, [r2, r5, lsr #14] @ Put register 'Rn'
str r7, [r2, r9, lsr #14] @ Put register 'Rn'
b do_DataAbort

.data_arm_lateldrpreconst:
Expand All @@ -118,12 +117,12 @@ ENTRY(cpu_arm6_data_abort)
.data_arm_lateldrpostconst:
movs r6, r8, lsl #20 @ Get offset
beq do_DataAbort @ zero -> no fixup
and r5, r8, #15 << 16 @ Extract 'n' from instruction
ldr r7, [r2, r5, lsr #14] @ Get register 'Rn'
and r9, r8, #15 << 16 @ Extract 'n' from instruction
ldr r7, [r2, r9, lsr #14] @ Get register 'Rn'
tst r8, #1 << 23 @ Check U bit
subne r7, r7, r6, lsr #20 @ Undo increment
addeq r7, r7, r6, lsr #20 @ Undo decrement
str r7, [r2, r5, lsr #14] @ Put register 'Rn'
str r7, [r2, r9, lsr #14] @ Put register 'Rn'
b do_DataAbort

.data_arm_lateldrprereg:
Expand All @@ -132,38 +131,38 @@ ENTRY(cpu_arm6_data_abort)
.data_arm_lateldrpostreg:
and r7, r8, #15 @ Extract 'm' from instruction
ldr r6, [r2, r7, lsl #2] @ Get register 'Rm'
mov r5, r8, lsr #7 @ get shift count
ands r5, r5, #31
mov r9, r8, lsr #7 @ get shift count
ands r9, r9, #31
and r7, r8, #0x70 @ get shift type
orreq r7, r7, #8 @ shift count = 0
add pc, pc, r7
nop

mov r6, r6, lsl r5 @ 0: LSL #!0
mov r6, r6, lsl r9 @ 0: LSL #!0
b .data_arm_apply_r6_and_rn
b .data_arm_apply_r6_and_rn @ 1: LSL #0
nop
b .data_unknown @ 2: MUL?
nop
b .data_unknown @ 3: MUL?
nop
mov r6, r6, lsr r5 @ 4: LSR #!0
mov r6, r6, lsr r9 @ 4: LSR #!0
b .data_arm_apply_r6_and_rn
mov r6, r6, lsr #32 @ 5: LSR #32
b .data_arm_apply_r6_and_rn
b .data_unknown @ 6: MUL?
nop
b .data_unknown @ 7: MUL?
nop
mov r6, r6, asr r5 @ 8: ASR #!0
mov r6, r6, asr r9 @ 8: ASR #!0
b .data_arm_apply_r6_and_rn
mov r6, r6, asr #32 @ 9: ASR #32
b .data_arm_apply_r6_and_rn
b .data_unknown @ A: MUL?
nop
b .data_unknown @ B: MUL?
nop
mov r6, r6, ror r5 @ C: ROR #!0
mov r6, r6, ror r9 @ C: ROR #!0
b .data_arm_apply_r6_and_rn
mov r6, r6, rrx @ D: RRX
b .data_arm_apply_r6_and_rn
Expand Down

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