forked from luck/tmp_suning_uos_patched
26ffd0d43b
PROT_NONE mappings apply the page protection attributes defined by _P000 which translate to PAGE_NONE for ARM. These attributes specify an XN, RDONLY pte that is inaccessible to userspace. However, on kernels configured without support for domains, such a pte *is* accessible to the kernel and can be read via get_user, allowing tasks to read PROT_NONE pages via syscalls such as read/write over a pipe. This patch introduces a new software pte flag, L_PTE_NONE, that is set to identify faulting, present entries. Signed-off-by: Will Deacon <will.deacon@arm.com>
176 lines
4.5 KiB
ArmAsm
176 lines
4.5 KiB
ArmAsm
/*
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* arch/arm/mm/proc-v7-2level.S
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*
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* Copyright (C) 2001 Deep Blue Solutions Ltd.
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#define TTB_S (1 << 1)
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#define TTB_RGN_NC (0 << 3)
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#define TTB_RGN_OC_WBWA (1 << 3)
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#define TTB_RGN_OC_WT (2 << 3)
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#define TTB_RGN_OC_WB (3 << 3)
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#define TTB_NOS (1 << 5)
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#define TTB_IRGN_NC ((0 << 0) | (0 << 6))
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#define TTB_IRGN_WBWA ((0 << 0) | (1 << 6))
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#define TTB_IRGN_WT ((1 << 0) | (0 << 6))
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#define TTB_IRGN_WB ((1 << 0) | (1 << 6))
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/* PTWs cacheable, inner WB not shareable, outer WB not shareable */
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#define TTB_FLAGS_UP TTB_IRGN_WB|TTB_RGN_OC_WB
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#define PMD_FLAGS_UP PMD_SECT_WB
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/* PTWs cacheable, inner WBWA shareable, outer WBWA not shareable */
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#define TTB_FLAGS_SMP TTB_IRGN_WBWA|TTB_S|TTB_NOS|TTB_RGN_OC_WBWA
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#define PMD_FLAGS_SMP PMD_SECT_WBWA|PMD_SECT_S
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/*
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* cpu_v7_switch_mm(pgd_phys, tsk)
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*
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* Set the translation table base pointer to be pgd_phys
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*
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* - pgd_phys - physical address of new TTB
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*
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* It is assumed that:
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* - we are not using split page tables
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*/
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ENTRY(cpu_v7_switch_mm)
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#ifdef CONFIG_MMU
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mov r2, #0
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ldr r1, [r1, #MM_CONTEXT_ID] @ get mm->context.id
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ALT_SMP(orr r0, r0, #TTB_FLAGS_SMP)
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ALT_UP(orr r0, r0, #TTB_FLAGS_UP)
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#ifdef CONFIG_ARM_ERRATA_430973
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mcr p15, 0, r2, c7, c5, 6 @ flush BTAC/BTB
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#endif
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#ifdef CONFIG_PID_IN_CONTEXTIDR
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mrc p15, 0, r2, c13, c0, 1 @ read current context ID
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lsr r2, r2, #8 @ extract the PID
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bfi r1, r2, #8, #24 @ insert into new context ID
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#endif
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#ifdef CONFIG_ARM_ERRATA_754322
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dsb
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#endif
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mcr p15, 0, r1, c13, c0, 1 @ set context ID
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isb
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mcr p15, 0, r0, c2, c0, 0 @ set TTB 0
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isb
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#endif
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mov pc, lr
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ENDPROC(cpu_v7_switch_mm)
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/*
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* cpu_v7_set_pte_ext(ptep, pte)
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*
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* Set a level 2 translation table entry.
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*
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* - ptep - pointer to level 2 translation table entry
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* (hardware version is stored at +2048 bytes)
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* - pte - PTE value to store
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* - ext - value for extended PTE bits
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*/
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ENTRY(cpu_v7_set_pte_ext)
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#ifdef CONFIG_MMU
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str r1, [r0] @ linux version
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bic r3, r1, #0x000003f0
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bic r3, r3, #PTE_TYPE_MASK
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orr r3, r3, r2
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orr r3, r3, #PTE_EXT_AP0 | 2
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tst r1, #1 << 4
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orrne r3, r3, #PTE_EXT_TEX(1)
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eor r1, r1, #L_PTE_DIRTY
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tst r1, #L_PTE_RDONLY | L_PTE_DIRTY
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orrne r3, r3, #PTE_EXT_APX
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tst r1, #L_PTE_USER
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orrne r3, r3, #PTE_EXT_AP1
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#ifdef CONFIG_CPU_USE_DOMAINS
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@ allow kernel read/write access to read-only user pages
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tstne r3, #PTE_EXT_APX
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bicne r3, r3, #PTE_EXT_APX | PTE_EXT_AP0
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#endif
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tst r1, #L_PTE_XN
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orrne r3, r3, #PTE_EXT_XN
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tst r1, #L_PTE_YOUNG
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tstne r1, #L_PTE_VALID
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#ifndef CONFIG_CPU_USE_DOMAINS
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eorne r1, r1, #L_PTE_NONE
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tstne r1, #L_PTE_NONE
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#endif
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moveq r3, #0
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ARM( str r3, [r0, #2048]! )
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THUMB( add r0, r0, #2048 )
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THUMB( str r3, [r0] )
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mcr p15, 0, r0, c7, c10, 1 @ flush_pte
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#endif
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mov pc, lr
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ENDPROC(cpu_v7_set_pte_ext)
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/*
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* Memory region attributes with SCTLR.TRE=1
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*
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* n = TEX[0],C,B
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* TR = PRRR[2n+1:2n] - memory type
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* IR = NMRR[2n+1:2n] - inner cacheable property
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* OR = NMRR[2n+17:2n+16] - outer cacheable property
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*
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* n TR IR OR
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* UNCACHED 000 00
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* BUFFERABLE 001 10 00 00
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* WRITETHROUGH 010 10 10 10
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* WRITEBACK 011 10 11 11
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* reserved 110
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* WRITEALLOC 111 10 01 01
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* DEV_SHARED 100 01
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* DEV_NONSHARED 100 01
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* DEV_WC 001 10
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* DEV_CACHED 011 10
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*
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* Other attributes:
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*
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* DS0 = PRRR[16] = 0 - device shareable property
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* DS1 = PRRR[17] = 1 - device shareable property
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* NS0 = PRRR[18] = 0 - normal shareable property
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* NS1 = PRRR[19] = 1 - normal shareable property
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* NOS = PRRR[24+n] = 1 - not outer shareable
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*/
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.equ PRRR, 0xff0a81a8
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.equ NMRR, 0x40e040e0
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/*
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* Macro for setting up the TTBRx and TTBCR registers.
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* - \ttb0 and \ttb1 updated with the corresponding flags.
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*/
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.macro v7_ttb_setup, zero, ttbr0, ttbr1, tmp
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mcr p15, 0, \zero, c2, c0, 2 @ TTB control register
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ALT_SMP(orr \ttbr0, \ttbr0, #TTB_FLAGS_SMP)
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ALT_UP(orr \ttbr0, \ttbr0, #TTB_FLAGS_UP)
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ALT_SMP(orr \ttbr1, \ttbr1, #TTB_FLAGS_SMP)
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ALT_UP(orr \ttbr1, \ttbr1, #TTB_FLAGS_UP)
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mcr p15, 0, \ttbr1, c2, c0, 1 @ load TTB1
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.endm
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__CPUINIT
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/* AT
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* TFR EV X F I D LR S
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* .EEE ..EE PUI. .T.T 4RVI ZWRS BLDP WCAM
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* rxxx rrxx xxx0 0101 xxxx xxxx x111 xxxx < forced
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* 01 0 110 0011 1100 .111 1101 < we want
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*/
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.align 2
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.type v7_crval, #object
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v7_crval:
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crval clear=0x2120c302, mmuset=0x10c03c7d, ucset=0x00c01c7c
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.previous
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