On Sun, May 31, 2026 at 05:29:57AM +0000, Gustavo Kenji Mendonça Kaneko wrote: > malidp_runtime_pm_resume() calls clk_prepare_enable() three times > without checking the return value. If any clock fails to enable, the > driver silently proceeds with unclocked hardware, leading to undefined > behavior. > > Use clk_bulk_prepare_enable() which atomically enables all clocks and > automatically rolls back successfully enabled clocks on failure. This > is consistent with how the suspend path already uses > clk_bulk_disable_unprepare() in malidp_runtime_pm_suspend(). > > This issue was found by code review without access to Mali DP hardware. > > Signed-off-by: Gustavo Kenji Mendonça Kaneko <[email protected]>
Reviewed-by: Liviu Dudau <[email protected]> Best regards, Liviu > --- > drivers/gpu/drm/arm/malidp_drv.c | 13 ++++++++++--- > 1 file changed, 10 insertions(+), 3 deletions(-) > > diff --git a/drivers/gpu/drm/arm/malidp_drv.c > b/drivers/gpu/drm/arm/malidp_drv.c > index b765f6c9eea4..1e4336c3a2fa 100644 > --- a/drivers/gpu/drm/arm/malidp_drv.c > +++ b/drivers/gpu/drm/arm/malidp_drv.c > @@ -689,10 +689,17 @@ static int malidp_runtime_pm_resume(struct device *dev) > struct drm_device *drm = dev_get_drvdata(dev); > struct malidp_drm *malidp = drm_to_malidp(drm); > struct malidp_hw_device *hwdev = malidp->dev; > + struct clk_bulk_data clks[] = { > + { .clk = hwdev->pclk }, > + { .clk = hwdev->aclk }, > + { .clk = hwdev->mclk }, > + }; > + int err; > + > + err = clk_bulk_prepare_enable(ARRAY_SIZE(clks), clks); > + if (err) > + return err; > > - clk_prepare_enable(hwdev->pclk); > - clk_prepare_enable(hwdev->aclk); > - clk_prepare_enable(hwdev->mclk); > hwdev->pm_suspended = false; > malidp_de_irq_hw_init(hwdev); > malidp_se_irq_hw_init(hwdev); > -- > 2.54.0 > > -- ==================== | I would like to | | fix the world, | | but they're not | | giving me the | \ source code! / --------------- ¯\_(ツ)_/¯
