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: d375b356e687 ("coresight: Fix support for sparsely populated ports") Reported-by: Ruediger Oertel <r...@suse.com> Signed-off-by: Mian Yousaf Kaukab <ykau...@suse.de> --- drivers/hwtracing/coresight/coresight-platform.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/drivers/hwtracing/coresight/coresight-platform.c b/drivers/hwtracing/coresight/coresight-platform.c index bfd44231d7ad..227e234a2470 100644 --- a/drivers/hwtracing/coresight/coresight-platform.c +++ b/drivers/hwtracing/coresight/coresight-platform.c @@ -711,11 +711,11 @@ static int acpi_coresight_parse_graph(struct acpi_device *adev, return dir; if (dir == ACPI_CORESIGHT_LINK_MASTER) { - if (ptr->outport > pdata->nr_outport) - pdata->nr_outport = ptr->outport; + if (ptr->outport >= pdata->nr_outport) + pdata->nr_outport = ptr->outport + 1; ptr++; } else { - WARN_ON(pdata->nr_inport == ptr->child_port); + WARN_ON(pdata->nr_inport == ptr->child_port + 1); /* * We do not track input port connections for a device. * However we need the highest port number described, @@ -723,8 +723,8 @@ static int acpi_coresight_parse_graph(struct acpi_device *adev, * record for an output connection. Hence, do not move * the ptr for input connections */ - if (ptr->child_port > pdata->nr_inport) - pdata->nr_inport = ptr->child_port; + if (ptr->child_port >= pdata->nr_inport) + pdata->nr_inport = ptr->child_port + 1; } } -- 2.26.2