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From: wangxiaoming321 <xiaoming.wang@intel.com>
To: lucas.demarchi@intel.com,
	ogabbay@kernel.org,
	thomas.hellstrom@linux.intel.com,
	maarten.lankhorst@linux.intel.com,
	mripard@kernel.org,
	tzimmermann@suse.de,
	airlied@gmail.com,
	daniel@ffwll.ch,
	intel-xe@lists.freedesktop.org,
	dri-devel@lists.freedesktop.org,
	linux-kernel@vger.kernel.org
Cc: wangxiaoming321 <xiaoming.wang@intel.com>
Subject: [PATCH] drm/xe/display: Fix memleak in display initialization
Date: Fri, 26 Jan 2024 22:34:33 +0800
Message-Id: <20240126143433.997078-1-xiaoming.wang@intel.com>
In-Reply-To: <20240125063633.989944-1-xiaoming.wang@intel.com>
References: <20240125063633.989944-1-xiaoming.wang@intel.com>
Precedence: bulk
MIME-Version: 1.0
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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@intel.com>
---
 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