Re: [PATCH AUTOSEL 6.0 38/44] drm/amdgpu: Unlock bo_list_mutex after error handling
On Mon, Nov 21, 2022 at 12:07:40PM +0100, Christian König wrote:
Am 21.11.22 um 10:57 schrieb Michel Dänzer:
On 11/19/22 03:11, Sasha Levin wrote:
From: Philip Yang
[ Upstream commit 64f65135c41a75f933d3bca236417ad8e9eb75de ]
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:
(>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
Reviewed-by: Christian König
Signed-off-by: Alex Deucher
Signed-off-by: Sasha Levin
---
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 b7bae833c804..9d59f83c8faa 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
@@ -655,6 +655,7 @@ static int amdgpu_cs_parser_bos(struct amdgpu_cs_parser *p,
}
mutex_unlock(>bo_list->bo_list_mutex);
}
+ mutex_unlock(>bo_list->bo_list_mutex);
return r;
}
Looks doubtful that this is a correct backport — there's an identical
mutex_unlock call just above.
Oh, yes good point. This patch doesn't needs to be backported at all
because it just fixes a problem introduced in the same cycle:
Dropping it, thanks!
--
Thanks,
Sasha
Re: [PATCH AUTOSEL 6.0 38/44] drm/amdgpu: Unlock bo_list_mutex after error handling
Am 21.11.22 um 10:57 schrieb Michel Dänzer:
On 11/19/22 03:11, Sasha Levin wrote:
From: Philip Yang
[ Upstream commit 64f65135c41a75f933d3bca236417ad8e9eb75de ]
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:
(>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
Reviewed-by: Christian König
Signed-off-by: Alex Deucher
Signed-off-by: Sasha Levin
---
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 b7bae833c804..9d59f83c8faa 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
@@ -655,6 +655,7 @@ static int amdgpu_cs_parser_bos(struct amdgpu_cs_parser *p,
}
mutex_unlock(>bo_list->bo_list_mutex);
}
+ mutex_unlock(>bo_list->bo_list_mutex);
return r;
}
Looks doubtful that this is a correct backport — there's an identical
mutex_unlock call just above.
Oh, yes good point. This patch doesn't needs to be backported at all
because it just fixes a problem introduced in the same cycle:
commit 4953b6b22ab9d7f64706631a027b1ed1130ce4c8
Author: Christian König
Date: Tue Sep 13 09:52:13 2022 +0200
drm/amdgpu: cleanup error handling in amdgpu_cs_parser_bos
Return early on success and so remove all those "if (r)" in the error
path.
Signed-off-by: Christian König
Reviewed-by: Alex Deucher
Signed-off-by: Alex Deucher
Regards,
Christian.
Re: [PATCH AUTOSEL 6.0 38/44] drm/amdgpu: Unlock bo_list_mutex after error handling
On 11/19/22 03:11, Sasha Levin wrote:
> From: Philip Yang
>
> [ Upstream commit 64f65135c41a75f933d3bca236417ad8e9eb75de ]
>
> 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:
> (>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
> Reviewed-by: Christian König
> Signed-off-by: Alex Deucher
> Signed-off-by: Sasha Levin
> ---
> 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 b7bae833c804..9d59f83c8faa 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
> @@ -655,6 +655,7 @@ static int amdgpu_cs_parser_bos(struct amdgpu_cs_parser
> *p,
> }
> mutex_unlock(>bo_list->bo_list_mutex);
> }
> + mutex_unlock(>bo_list->bo_list_mutex);
> return r;
> }
>
Looks doubtful that this is a correct backport — there's an identical
mutex_unlock call just above.
--
Earthling Michel Dänzer| https://redhat.com
Libre software enthusiast | Mesa and Xwayland developer
