Brajesh Gupta 5dfd429591 drm/imagination: Fix segfault when updating ftrace mask
Fix invalid data access by passing right data for debugfs entry.

[  171.549793] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
[  171.559248] Mem abort info:
[  171.562173]   ESR = 0x0000000096000044
[  171.566227]   EC = 0x25: DABT (current EL), IL = 32 bits
[  171.573108]   SET = 0, FnV = 0
[  171.576448]   EA = 0, S1PTW = 0
[  171.579745]   FSC = 0x04: level 0 translation fault
[  171.584760] Data abort info:
[  171.588012]   ISV = 0, ISS = 0x00000044, ISS2 = 0x00000000
[  171.593734]   CM = 0, WnR = 1, TnD = 0, TagAccess = 0
[  171.598962]   GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
[  171.604471] user pgtable: 4k pages, 48-bit VAs, pgdp=0000000083837000
[  171.611358] [0000000000000000] pgd=0000000000000000, p4d=0000000000000000
[  171.618500] Internal error: Oops: 0000000096000044 [#1]  SMP
[  171.624222] Modules linked in: powervr drm_shmem_helper drm_gpuvm...
[  171.656580] CPU: 0 UID: 0 PID: 549 Comm: bash Not tainted 7.0.0-rc2-g730b257ba723-dirty #13 PREEMPT
[  171.665773] Hardware name: BeagleBoard.org BeaglePlay (DT)
[  171.671296] pstate: 20000005 (nzCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[  171.678306] pc : pvr_fw_trace_mask_set+0x78/0x154 [powervr]
[  171.683959] lr : pvr_fw_trace_mask_set+0x4c/0x154 [powervr]
[  171.689593] sp : ffff8000835ebb90
[  171.692929] x29: ffff8000835ebc00 x28: ffff000005c60f80 x27: 0000000000000000
[  171.700130] x26: 0000000000000000 x25: ffff00000504af28 x24: 0000000000000000
[  171.707324] x23: ffff00000504af50 x22: 0000000000000203 x21: 0000000000000000
[  171.714518] x20: ffff000005c44a80 x19: ffff000005c457b8 x18: 0000000000000000
[  171.721715] x17: 0000000000000000 x16: 0000000000000000 x15: 0000aaaae8887580
[  171.728908] x14: 0000000000000000 x13: 0000000000000000 x12: ffff8000835ebc30
[  171.736095] x11: ffff00000504af2a x10: ffff00008504af29 x9 : 0fffffffffffffff
[  171.743286] x8 : ffff8000835ebbf8 x7 : 0000000000000000 x6 : 000000000000002a
[  171.750479] x5 : ffff00000504af2e x4 : 0000000000000000 x3 : 0000000000000010
[  171.757674] x2 : 0000000000000203 x1 : 0000000000000000 x0 : ffff8000835ebba0
[  171.764871] Call trace:
[  171.767342]  pvr_fw_trace_mask_set+0x78/0x154 [powervr] (P)
[  171.772984]  simple_attr_write_xsigned.isra.0+0xe0/0x19c
[  171.778341]  simple_attr_write+0x18/0x24
[  171.782296]  debugfs_attr_write+0x50/0x98
[  171.786341]  full_proxy_write+0x6c/0xa8
[  171.790208]  vfs_write+0xd4/0x350
[  171.793561]  ksys_write+0x70/0x108
[  171.796995]  __arm64_sys_write+0x1c/0x28
[  171.800952]  invoke_syscall+0x48/0x10c
[  171.804740]  el0_svc_common.constprop.0+0x40/0xe0
[  171.809487]  do_el0_svc+0x1c/0x28
[  171.812834]  el0_svc+0x34/0x108
[  171.816013]  el0t_64_sync_handler+0xa0/0xe4
[  171.820237]  el0t_64_sync+0x198/0x19c
[  171.823939] Code: 32000262 b90ac293 1a931056 9134e293 (b9000036)
[  171.830073] ---[ end trace 0000000000000000 ]---

Fixes: a331631496 ("drm/imagination: Simplify module parameters")
Signed-off-by: Brajesh Gupta <brajesh.gupta@imgtec.com>
Reviewed-by: Alessio Belle <alessio.belle@imgtec.com>
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260427-ftrace_fix-v3-1-e081530759a8@imgtec.com
Signed-off-by: Matt Coster <matt.coster@imgtec.com>
2026-04-27 14:22:52 +01:00
2026-01-26 19:07:09 -08:00
2022-09-28 09:02:20 +02:00
2025-02-19 14:53:27 -07:00
2026-04-26 14:19:00 -07:00

Linux kernel
============

The Linux kernel is the core of any Linux operating system. It manages hardware,
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-----------

* Report a bug: See Documentation/admin-guide/reporting-issues.rst
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-----------------------

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==================

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--------------------

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-------------------

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-----------------------------

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--------------------

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----------

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---------------

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-----------------------

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-------------------

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