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    ARM: 7781/1: mmu: Add debug_ll_io_init() mappings to early mappings · ee4de5d9
    Stephen Boyd 提交于
    Failure to add the mapping created in debug_ll_io_init() can lead
    to the BUG_ON() triggering in lib/ioremap.c:27 if the static
    virtual address decided for the debug_ll mapping overlaps with
    another mapping that is created later. This happens because the
    generic ioremap code has no idea there is a mapping there and it
    tries to place a mapping in the same location and blows up when
    it sees that there is a pte already present.
    
    kernel BUG at lib/ioremap.c:27!
    Internal error: Oops - BUG: 0 [#1] PREEMPT SMP ARM
    Modules linked in:
    CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.10.0-rc2-00042-g2af0c67-dirty #316
    task: ef088000 ti: ef082000 task.ti: ef082000
    PC is at ioremap_page_range+0x16c/0x198
    LR is at ioremap_page_range+0xf0/0x198
    pc : [<c04cb874>]    lr : [<c04cb7f8>]    psr: 20000113
    sp : ef083e78  ip : af140000  fp : ef083ebc
    r10: ef7fc100  r9 : ef7fc104  r8 : 000af174
    r7 : 00000647  r6 : beffffff  r5 : f004c000  r4 : f0040000
    r3 : af173417  r2 : 16440653  r1 : af173e07  r0 : ef7fc8fc
    Flags: nzCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment kernel
    Control: 10c5787d  Table: 8020406a  DAC: 00000015
    Process swapper/0 (pid: 1, stack limit = 0xef082238)
    Stack: (0xef083e78 to 0xef084000)
    3e60:                                                       00040000 ef083eec
    3e80: bf134000 f004bfff c0207c00 f004c000 c02fc120 f000c000 c15e7800 00040000
    3ea0: ef083eec 00000647 c098ba9c c0953544 ef083edc ef083ec0 c021b82c c04cb714
    3ec0: c09cdc50 00000040 ef0f1e00 ef1003c0 ef083f14 ef083ee0 c09535bc c021b7bc
    3ee0: c0953544 c04d0c6c c094e2cc c1600be4 c07440c4 c09a6888 00000002 c0a15f00
    3f00: ef082000 00000000 ef083f54 ef083f18 c0208728 c0953550 00000002 c1600bfc
    3f20: c08e3fac c0839918 ef083f54 c1600b80 c09a6888 c0a15f00 0000008b c094e2cc
    3f40: c098ba9c c098bab8 ef083f94 ef083f58 c094ea0c c020865c 00000002 00000002
    3f60: c094e2cc 00000000 c025b674 00000000 c06ff860 00000000 00000000 00000000
    3f80: 00000000 00000000 ef083fac ef083f98 c06ff878 c094e910 00000000 00000000
    3fa0: 00000000 ef083fb0 c020efe8 c06ff86c 00000000 00000000 00000000 00000000
    3fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
    3fe0: 00000000 00000000 00000000 00000000 00000013 00000000 00000000 c0595108
    [<c04cb874>] (ioremap_page_range+0x16c/0x198) from [<c021b82c>] (__alloc_remap_buffer.isra.18+0x7c/0xc4)
    [<c021b82c>] (__alloc_remap_buffer.isra.18+0x7c/0xc4) from [<c09535bc>] (atomic_pool_init+0x78/0x128)
    [<c09535bc>] (atomic_pool_init+0x78/0x128) from [<c0208728>] (do_one_initcall+0xd8/0x198)
    [<c0208728>] (do_one_initcall+0xd8/0x198) from [<c094ea0c>] (kernel_init_freeable+0x108/0x1d0)
    [<c094ea0c>] (kernel_init_freeable+0x108/0x1d0) from [<c06ff878>] (kernel_init+0x18/0xf4)
    [<c06ff878>] (kernel_init+0x18/0xf4) from [<c020efe8>] (ret_from_fork+0x14/0x20)
    Code: e50b0040 ebf54b2f e51b0040 eaffffee (e7f001f2)
    
    Fix it by telling generic layers about the static mapping via
    iotable_init().  This also has the nice side effect of letting
    you see the mapping in procfs' vmallocinfo file.
    
    Cc: Rob Herring <rob.herring@calxeda.com>
    Cc: Stephen Warren <swarren@nvidia.com>
    Signed-off-by: NStephen Boyd <sboyd@codeaurora.org>
    Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
    ee4de5d9
mmu.c 34.7 KB