Hi Anitha,
On Tue, Jul 27, 2021 at 05:31:24PM -0700, Anitha Chrisanthus wrote:
If kmb_dsi_init() fails the "kmb->kmb_dsi" variable is an error pointer. This can potentially result in kernel panic when kmb_dsi_host_unregister is called.
Fixes: 7f7b96a8a0a1 ("drm/kmb: Add support for KeemBay Display") Fixes: 98521f4d4b4c ("drm/kmb: Mipi DSI part of the display driver") Cc: Dan Carpenter dan.carpenter@oracle.com Signed-off-by: Anitha Chrisanthus anitha.chrisanthus@intel.com
drivers/gpu/drm/kmb/kmb_drv.c | 9 ++++++--- drivers/gpu/drm/kmb/kmb_dsi.c | 9 +++++---- drivers/gpu/drm/kmb/kmb_dsi.h | 3 ++- 3 files changed, 13 insertions(+), 8 deletions(-)
diff --git a/drivers/gpu/drm/kmb/kmb_drv.c b/drivers/gpu/drm/kmb/kmb_drv.c index bb7eca9e13ae..12f35c43d838 100644 --- a/drivers/gpu/drm/kmb/kmb_drv.c +++ b/drivers/gpu/drm/kmb/kmb_drv.c @@ -454,8 +454,9 @@ static int kmb_remove(struct platform_device *pdev) dev_set_drvdata(dev, NULL);
/* Unregister DSI host */
- kmb_dsi_host_unregister(kmb->kmb_dsi);
- kmb_dsi_host_unregister(); drm_atomic_helper_shutdown(drm);
- drm_dev_put(drm); return 0;
}
@@ -519,7 +520,7 @@ static int kmb_probe(struct platform_device *pdev) if (IS_ERR(kmb->kmb_dsi)) { drm_err(&kmb->drm, "failed to initialize DSI\n"); ret = PTR_ERR(kmb->kmb_dsi);
goto err_free1;
goto err_free2;
}
kmb->kmb_dsi->dev = &dsi_pdev->dev;
@@ -555,8 +556,10 @@ static int kmb_probe(struct platform_device *pdev) drm_crtc_cleanup(&kmb->crtc); drm_mode_config_cleanup(&kmb->drm); err_free1:
- kmb_dsi_clk_disable(kmb->kmb_dsi);
- err_free2: dev_set_drvdata(dev, NULL);
- kmb_dsi_host_unregister(kmb->kmb_dsi);
- kmb_dsi_host_unregister();
This really looks like a step backward. There should not be a eed to call unregister if kmb_dsi is not a valid pointer in the first place. Also drn_dev_put() should not be needed with the use of drmm infrastructure.
return ret; } diff --git a/drivers/gpu/drm/kmb/kmb_dsi.c b/drivers/gpu/drm/kmb/kmb_dsi.c index 1cca0fe6f35f..a500172ada87 100644 --- a/drivers/gpu/drm/kmb/kmb_dsi.c +++ b/drivers/gpu/drm/kmb/kmb_dsi.c @@ -172,17 +172,17 @@ mipi_hs_freq_range[MIPI_DPHY_DEFAULT_BIT_RATES] = { {.default_bit_rate_mbps = 2500, .hsfreqrange_code = 0x49} };
-static void kmb_dsi_clk_disable(struct kmb_dsi *kmb_dsi) +void kmb_dsi_clk_disable(struct kmb_dsi *kmb_dsi) { clk_disable_unprepare(kmb_dsi->clk_mipi); clk_disable_unprepare(kmb_dsi->clk_mipi_ecfg); clk_disable_unprepare(kmb_dsi->clk_mipi_cfg); }
-void kmb_dsi_host_unregister(struct kmb_dsi *kmb_dsi) +void kmb_dsi_host_unregister(void) {
- kmb_dsi_clk_disable(kmb_dsi);
- mipi_dsi_host_unregister(kmb_dsi->host);
- if (dsi_host)
mipi_dsi_host_unregister(dsi_host);
}
I thought we had killed the global dsi_host variable?? Seems some cleanup is till needed here.
Sam