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From c6c48acdee6297631fd6b52263526e14a459e4e3 Mon Sep 17 00:00:00 2001
From: Philip Yang <Philip.Yang@amd.com>
Date: Thu, 3 Nov 2022 10:24:52 -0400
Subject: drm/amdgpu: Unlock bo_list_mutex after error handling
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Git-commit: 64f65135c41a75f933d3bca236417ad8e9eb75de
Patch-mainline: v6.1-rc5
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225 jsc#PED-2849

Get below kernel WARNING backtrace when pressing ctrl-C to kill kfdtest
application.

If amdgpu_cs_parser_bos returns error after taking bo_list_mutex, as
caller amdgpu_cs_ioctl will not unlock bo_list_mutex, this generates the
kernel WARNING.

Add unlock bo_list_mutex after amdgpu_cs_parser_bos error handling to
cleanup bo_list userptr bo.

 WARNING: kfdtest/2930 still has locks held!
 1 lock held by kfdtest/2930:
  (&list->bo_list_mutex){+.+.}-{3:3}, at: amdgpu_cs_ioctl+0xce5/0x1f10 [amdgpu]
  stack backtrace:
   dump_stack_lvl+0x44/0x57
   get_signal+0x79f/0xd00
   arch_do_signal_or_restart+0x36/0x7b0
   exit_to_user_mode_prepare+0xfd/0x1b0
   syscall_exit_to_user_mode+0x19/0x40
   do_syscall_64+0x40/0x80

Signed-off-by: Philip Yang <Philip.Yang@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
index 1bbd39b3b0fc..d371000a5727 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
@@ -992,6 +992,7 @@ static int amdgpu_cs_parser_bos(struct amdgpu_cs_parser *p,
 		kvfree(e->user_pages);
 		e->user_pages = NULL;
 	}
+	mutex_unlock(&p->bo_list->bo_list_mutex);
 	return r;
 }
 
-- 
2.38.1