From 7117007edad2299f2f093cdcfa813beb646d913e Mon Sep 17 00:00:00 2001
From: Alan Liu <HaoPing.Liu@amd.com>
Date: Mon, 24 Oct 2022 14:15:30 +0800
Subject: drm/amdgpu: Move the mutex_lock to protect the return status of
securedisplay command buffer
[Why]
Before we call psp_securedisplay_invoke(), we call
psp_prep_securedisplay_cmd_buf() to prepare and initialize the command
buffer.
However, we didn't use the mutex_lock to protect the status of command
buffer. So when multiple threads are using the command buffer, after
thread A return from psp_securedisplay_invoke() and the command buffer
status is set to SUCCESS, another thread B may call
psp_prep_securedisplay_cmd_buf() and initialize the status to FAILURE
again, and cause Thread A to get a failure return status.
[How]
Move the mutex_lock out of psp_securedisplay_invoke() to its caller to
cover psp_prep_securedisplay_cmd_buf() and the code checking the return
status of command buffer.
Signed-off-by: Alan Liu <HaoPing.Liu@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_securedisplay.c | 4 ++++
1 file changed, 4 insertions(+)
(limited to 'drivers/gpu/drm/amd/amdgpu/amdgpu_securedisplay.c')
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_securedisplay.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_securedisplay.c
index cc7597a15fe9..2c1d82fc4c34 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_securedisplay.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_securedisplay.c
@@ -121,6 +121,7 @@ static ssize_t amdgpu_securedisplay_debugfs_write(struct file *f, const char __u
switch (op) {
case 1:
+ mutex_lock(&psp->securedisplay_context.mutex);
psp_prep_securedisplay_cmd_buf(psp, &securedisplay_cmd,
TA_SECUREDISPLAY_COMMAND__QUERY_TA);
ret = psp_securedisplay_invoke(psp, TA_SECUREDISPLAY_COMMAND__QUERY_TA);
@@ -131,8 +132,10 @@ static ssize_t amdgpu_securedisplay_debugfs_write(struct file *f, const char __u
else
psp_securedisplay_parse_resp_status(psp, securedisplay_cmd->status);
}
+ mutex_unlock(&psp->securedisplay_context.mutex);
break;
case 2:
+ mutex_lock(&psp->securedisplay_context.mutex);
psp_prep_securedisplay_cmd_buf(psp, &securedisplay_cmd,
TA_SECUREDISPLAY_COMMAND__SEND_ROI_CRC);
securedisplay_cmd->securedisplay_in_message.send_roi_crc.phy_id = phy_id;
@@ -146,6 +149,7 @@ static ssize_t amdgpu_securedisplay_debugfs_write(struct file *f, const char __u
psp_securedisplay_parse_resp_status(psp, securedisplay_cmd->status);
}
}
+ mutex_unlock(&psp->securedisplay_context.mutex);
break;
default:
dev_err(adev->dev, "Invalid input: %s\n", str);
--
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