[PATCH 1/2] drm/imagination: Fix segfault when updating ftrace mask
From: Brajesh Gupta
Date: Fri Apr 17 2026 - 06:17:01 EST
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: a331631496a0 ("drm/imagination: Simplify module parameters")
Signed-off-by: Brajesh Gupta <brajesh.gupta@xxxxxxxxxx>
---
drivers/gpu/drm/imagination/pvr_fw_trace.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/imagination/pvr_fw_trace.c b/drivers/gpu/drm/imagination/pvr_fw_trace.c
index e154cb35f604..6193811ef7be 100644
--- a/drivers/gpu/drm/imagination/pvr_fw_trace.c
+++ b/drivers/gpu/drm/imagination/pvr_fw_trace.c
@@ -558,6 +558,6 @@ pvr_fw_trace_debugfs_init(struct pvr_device *pvr_dev, struct dentry *dir)
&pvr_fw_trace_fops);
}
- debugfs_create_file("trace_mask", 0600, dir, fw_trace,
+ debugfs_create_file("trace_mask", 0600, dir, pvr_dev,
&pvr_fw_trace_mask_fops);
}
--
2.43.0