• Mian Yousaf Kaukab's avatar
    coresight: fix offset by one error in counting ports · 9554c355
    Mian Yousaf Kaukab authored
    Since port-numbers start from 0, add 1 to port-number to get the port
    count.
    
    Fix following crash when Coresight is enabled on ACPI based systems:
    
    [   61.061736] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000008
    ...
    [   61.135494] pc : acpi_coresight_parse_graph+0x1c4/0x37c
    [   61.140705] lr : acpi_coresight_parse_graph+0x160/0x37c
    [   61.145915] sp : ffff800012f4ba40
    [   61.145917] x29: ffff800012f4ba40 x28: ffff00becce62f98
    [   61.159896] x27: 0000000000000005 x26: ffff00becd8a7c88
    [   61.165195] x25: ffff00becd8a7d88 x24: ffff00becce62f80
    [   61.170492] x23: ffff800011ef99c0 x22: ffff009efb8bc010
    [   61.175790] x21: 0000000000000018 x20: 0000000000000005
    [   61.181087] x19: ffff00becce62e80 x18: 0000000000000020
    [   61.186385] x17: 0000000000000001 x16: 00000000000002a8
    [   61.191682] x15: ffff000838648550 x14: ffffffffffffffff
    [   61.196980] x13: 0000000000000000 x12: ffff00becce62d87
    [   61.202277] x11: 00000000ffffff76 x10: 000000000000002e
    [   61.207575] x9 : ffff8000107e1a68 x8 : ffff00becce63000
    [   61.212873] x7 : 0000000000000018 x6 : 000000000000003f
    [   61.218170] x5 : 0000000000000000 x4 : 0000000000000000
    [   61.223467] x3 : 0000000000000000 x2 : 0000000000000000
    [   61.228764] x1 : ffff00becce62f80 x0 : 0000000000000000
    [   61.234062] Call trace:
    [   61.236497]  acpi_coresight_parse_graph+0x1c4/0x37c
    [   61.241361]  coresight_get_platform_data+0xdc/0x130
    [   61.246225]  tmc_probe+0x138/0x2dc
    [   61.246227]  amba_probe+0xdc/0x220
    [   61.255779]  really_probe+0xe8/0x49c
    [   61.255781]  driver_probe_device+0xec/0x140
    [   61.255782]  device_driver_attach+0xc8/0xd0
    [   61.255785]  __driver_attach+0xac/0x180
    [   61.265857]  bus_for_each_dev+0x78/0xcc
    [   61.265859]  driver_attach+0x2c/0x40
    [   61.265861]  bus_add_driver+0x150/0x244
    [   61.265863]  driver_register+0x80/0x13c
    [   61.273591]  amba_driver_register+0x60/0x70
    [   61.273594]  tmc_driver_init+0x20/0x2c
    [   61.281582]  do_one_initcall+0x50/0x230
    [   61.281585]  do_initcalls+0x104/0x144
    [   61.291831]  kernel_init_freeable+0x168/0x1dc
    [   61.291834]  kernel_init+0x1c/0x120
    [   61.299215]  ret_from_fork+0x10/0x18
    [   61.299219] Code: b9400022 f9400660 9b277c42 8b020000 (f9400404)
    [   61.307381] ---[ end trace 63c6c3d7ec6a9b7c ]---
    [   61.315225] Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b
    
    Fixes: d375b356 ("coresight: Fix support for sparsely populated ports")
    Reported-by: default avatarRuediger Oertel <ro@suse.com>
    Tested-by: default avatarJeremy Linton <jeremy.linton@arm.com>
    Reviewed-by: default avatarSuzuki K Poulose <suzuki.poulose@arm.com>
    Reviewed-by: default avatarJeremy Linton <jeremy.linton@arm.com>
    Signed-off-by: default avatarMian Yousaf Kaukab <ykaukab@suse.de>
    Signed-off-by: default avatarMathieu Poirier <mathieu.poirier@linaro.org>
    Link: https://lore.kernel.org/r/20200916191737.4001561-4-mathieu.poirier@linaro.orgSigned-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
    9554c355
coresight-platform.c 21.7 KB