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

[Lucas De Marchi]

On Fri, Feb 02, 2024 at 01:56:58PM -0800, Lucas De Marchi wrote:
>From: Xiaoming Wang <xiaoming.wang at intel.com>
>
>intel_power_domains_init is called twice in xe_device_probe:
>xe_device_probe -> xe_display_init_nommio -> intel_power_domains_init()
>xe_device_probe -> xe_display_init_noirq -> intel_display_driver_probe_noirq
>-> intel_power_domains_init(i915)
>
>It needs remove one 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
>
>The call to intel_power_domains_cleanup() needs to stay where it is for
>now. The main issue is that while the init is called by the display
>side, shared by i915 and xe, the cleanup is called by a non-shared code
>path. Fixing that will be done as a separate commit.
>
>Fixes: 44e694958b95 ("drm/xe/display: Implement display support")
>Signed-off-by: Xiaoming Wang <xiaoming.wang at intel.com>
>[ reword commit message and explain why the fini needs to stay
>  where it is ]
>Reviewed-by: Lucas De Marchi <lucas.demarchi at intel.com>
>Signed-off-by: Lucas De Marchi <lucas.demarchi at intel.com>

applied, thanks

Lucas De Marchi

>---
> drivers/gpu/drm/xe/display/xe_display.c | 6 ------
> 1 file changed, 6 deletions(-)
>
>diff --git a/drivers/gpu/drm/xe/display/xe_display.c b/drivers/gpu/drm/xe/display/xe_display.c
>index 74391d9b11ae..e4db069f0db3 100644
>--- a/drivers/gpu/drm/xe/display/xe_display.c
>+++ b/drivers/gpu/drm/xe/display/xe_display.c
>@@ -134,8 +134,6 @@ static void xe_display_fini_nommio(struct drm_device *dev, void *dummy)
>
> int xe_display_init_nommio(struct xe_device *xe)
> {
>-	int err;
>-
> 	if (!xe->info.enable_display)
> 		return 0;
>
>@@ -145,10 +143,6 @@ int xe_display_init_nommio(struct xe_device *xe)
> 	/* This must be called before any calls to HAS_PCH_* */
> 	intel_detect_pch(xe);
>
>-	err = intel_power_domains_init(xe);
>-	if (err)
>-		return err;
>-
> 	return drmm_add_action_or_reset(&xe->drm, xe_display_fini_nommio, xe);
> }
>
>-- 
>2.43.0
>