[PATCH] drm/xe/display: Fix memleak in display initialization

From: wangxiaoming321
Date: Fri Jan 26 2024 - 09:34:57 EST


intel_power_domains_init has been called twice in xe_device_probe:
xe_device_probe -> xe_display_init_nommio -> intel_power_domains_init(xe)
xe_device_probe -> xe_display_init_noirq -> intel_display_driver_probe_noirq
-> intel_power_domains_init(i915)

It needs add a flag to avoid power_domains->power_wells double malloc.

unreferenced object 0xffff88811150ee00 (size 512):
comm "systemd-udevd", pid 506, jiffies 4294674198 (age 3605.560s)
hex dump (first 32 bytes):
10 b4 9d a0 ff ff ff ff ff ff ff ff ff ff ff ff ................
ff ff ff ff ff ff ff ff 00 00 00 00 00 00 00 00 ................
backtrace:
[<ffffffff8134b901>] __kmem_cache_alloc_node+0x1c1/0x2b0
[<ffffffff812c98b2>] __kmalloc+0x52/0x150
[<ffffffffa08b0033>] __set_power_wells+0xc3/0x360 [xe]
[<ffffffffa08562fc>] xe_display_init_nommio+0x4c/0x70 [xe]
[<ffffffffa07f0d1c>] xe_device_probe+0x3c/0x5a0 [xe]
[<ffffffffa082e48f>] xe_pci_probe+0x33f/0x5a0 [xe]
[<ffffffff817f2187>] local_pci_probe+0x47/0xa0
[<ffffffff817f3db3>] pci_device_probe+0xc3/0x1f0
[<ffffffff8192f2a2>] really_probe+0x1a2/0x410
[<ffffffff8192f598>] __driver_probe_device+0x78/0x160
[<ffffffff8192f6ae>] driver_probe_device+0x1e/0x90
[<ffffffff8192f92a>] __driver_attach+0xda/0x1d0
[<ffffffff8192c95c>] bus_for_each_dev+0x7c/0xd0
[<ffffffff8192e159>] bus_add_driver+0x119/0x220
[<ffffffff81930d00>] driver_register+0x60/0x120
[<ffffffffa05e50a0>] 0xffffffffa05e50a0

Signed-off-by: wangxiaoming321 <xiaoming.wang@xxxxxxxxx>
---
drivers/gpu/drm/i915/display/intel_display_power.c | 8 ++++++++
1 file changed, 8 insertions(+)

diff --git a/drivers/gpu/drm/i915/display/intel_display_power.c b/drivers/gpu/drm/i915/display/intel_display_power.c
index bf9685acf75a..3b48a1cb7c54 100644
--- a/drivers/gpu/drm/i915/display/intel_display_power.c
+++ b/drivers/gpu/drm/i915/display/intel_display_power.c
@@ -36,6 +36,8 @@
for_each_power_well_reverse(__dev_priv, __power_well) \
for_each_if(test_bit((__domain), (__power_well)->domains.bits))

+static int intel_power_domains_init_flag = 0;
+
const char *
intel_display_power_domain_str(enum intel_display_power_domain domain)
{
@@ -1016,6 +1018,11 @@ int intel_power_domains_init(struct drm_i915_private *dev_priv)
{
struct i915_power_domains *power_domains = &dev_priv->display.power.domains;

+ if(intel_power_domains_init_flag == 1)
+ return 0;
+
+ intel_power_domains_init_flag++;
+
dev_priv->display.params.disable_power_well =
sanitize_disable_power_well_option(dev_priv,
dev_priv->display.params.disable_power_well);
@@ -1041,6 +1048,7 @@ int intel_power_domains_init(struct drm_i915_private *dev_priv)
*/
void intel_power_domains_cleanup(struct drm_i915_private *dev_priv)
{
+ intel_power_domains_init_flag = 0;
intel_display_power_map_cleanup(&dev_priv->display.power.domains);
}

--
2.25.1