Patch "drm/amd/display: Fix memory leak in dm_sw_fini()" has been added to the 5.15-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    drm/amd/display: Fix memory leak in dm_sw_fini()

to the 5.15-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     drm-amd-display-fix-memory-leak-in-dm_sw_fini.patch
and it can be found in the queue-5.15 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 978dec007ac1ff482c5e645221d026f2aa671059
Author: Armin Wolf <W_Armin@xxxxxx>
Date:   Tue Feb 13 01:50:50 2024 +0100

    drm/amd/display: Fix memory leak in dm_sw_fini()
    
    [ Upstream commit bae67893578d608e35691dcdfa90c4957debf1d3 ]
    
    After destroying dmub_srv, the memory associated with it is
    not freed, causing a memory leak:
    
    unreferenced object 0xffff896302b45800 (size 1024):
      comm "(udev-worker)", pid 222, jiffies 4294894636
      hex dump (first 32 bytes):
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
      backtrace (crc 6265fd77):
        [<ffffffff993495ed>] kmalloc_trace+0x29d/0x340
        [<ffffffffc0ea4a94>] dm_dmub_sw_init+0xb4/0x450 [amdgpu]
        [<ffffffffc0ea4e55>] dm_sw_init+0x15/0x2b0 [amdgpu]
        [<ffffffffc0ba8557>] amdgpu_device_init+0x1417/0x24e0 [amdgpu]
        [<ffffffffc0bab285>] amdgpu_driver_load_kms+0x15/0x190 [amdgpu]
        [<ffffffffc0ba09c7>] amdgpu_pci_probe+0x187/0x4e0 [amdgpu]
        [<ffffffff9968fd1e>] local_pci_probe+0x3e/0x90
        [<ffffffff996918a3>] pci_device_probe+0xc3/0x230
        [<ffffffff99805872>] really_probe+0xe2/0x480
        [<ffffffff99805c98>] __driver_probe_device+0x78/0x160
        [<ffffffff99805daf>] driver_probe_device+0x1f/0x90
        [<ffffffff9980601e>] __driver_attach+0xce/0x1c0
        [<ffffffff99803170>] bus_for_each_dev+0x70/0xc0
        [<ffffffff99804822>] bus_add_driver+0x112/0x210
        [<ffffffff99807245>] driver_register+0x55/0x100
        [<ffffffff990012d1>] do_one_initcall+0x41/0x300
    
    Fix this by freeing dmub_srv after destroying it.
    
    Fixes: 743b9786b14a ("drm/amd/display: Hook up the DMUB service in DM")
    Signed-off-by: Armin Wolf <W_Armin@xxxxxx>
    Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index f5b257cb32cbd..7385efe699f88 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -2088,6 +2088,7 @@ static int dm_sw_fini(void *handle)
 
 	if (adev->dm.dmub_srv) {
 		dmub_srv_destroy(adev->dm.dmub_srv);
+		kfree(adev->dm.dmub_srv);
 		adev->dm.dmub_srv = NULL;
 	}