The mxsfb->crtc.funcs may already be NULL when unloading the driver, in which case calling mxsfb_irq_disable() via drm_irq_uninstall() from mxsfb_unload() leads to NULL pointer dereference.
Since all we care about is masking the IRQ and mxsfb->base is still valid, just use that to clear and mask the IRQ.
Fixes: ae1ed00932819 ("drm: mxsfb: Stop using DRM simple display pipeline helper") Signed-off-by: Marek Vasut marex@denx.de Cc: Daniel Abrecht public@danielabrecht.ch Cc: Emil Velikov emil.l.velikov@gmail.com Cc: Laurent Pinchart laurent.pinchart@ideasonboard.com Cc: Sam Ravnborg sam@ravnborg.org Cc: Stefan Agner stefan@agner.ch --- drivers/gpu/drm/mxsfb/mxsfb_drv.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/mxsfb/mxsfb_drv.c b/drivers/gpu/drm/mxsfb/mxsfb_drv.c index ec0432fe1bdf8..86d78634a9799 100644 --- a/drivers/gpu/drm/mxsfb/mxsfb_drv.c +++ b/drivers/gpu/drm/mxsfb/mxsfb_drv.c @@ -173,7 +173,11 @@ static void mxsfb_irq_disable(struct drm_device *drm) struct mxsfb_drm_private *mxsfb = drm->dev_private;
mxsfb_enable_axi_clk(mxsfb); - mxsfb->crtc.funcs->disable_vblank(&mxsfb->crtc); + + /* Disable and clear VBLANK IRQ */ + writel(CTRL1_CUR_FRAME_DONE_IRQ_EN, mxsfb->base + LCDC_CTRL1 + REG_CLR); + writel(CTRL1_CUR_FRAME_DONE_IRQ, mxsfb->base + LCDC_CTRL1 + REG_CLR); + mxsfb_disable_axi_clk(mxsfb); }
On Tue, Sep 07, 2021 at 04:49:00AM +0200, Marek Vasut wrote:
The mxsfb->crtc.funcs may already be NULL when unloading the driver, in which case calling mxsfb_irq_disable() via drm_irq_uninstall() from mxsfb_unload() leads to NULL pointer dereference.
Since all we care about is masking the IRQ and mxsfb->base is still valid, just use that to clear and mask the IRQ.
Fixes: ae1ed00932819 ("drm: mxsfb: Stop using DRM simple display pipeline helper") Signed-off-by: Marek Vasut marex@denx.de Cc: Daniel Abrecht public@danielabrecht.ch Cc: Emil Velikov emil.l.velikov@gmail.com Cc: Laurent Pinchart laurent.pinchart@ideasonboard.com Cc: Sam Ravnborg sam@ravnborg.org Cc: Stefan Agner stefan@agner.ch
You probably want a drm_atomic_helper_shutdown instead of trying to do all that manually. We've also added a bunch more devm and drmm_ functions to automate the cleanup a lot more here, e.g. your drm_mode_config_cleanup is in the wrong place.
Also I'm confused because I'm not even seeing this function anywhere in upstream. -Daniel
drivers/gpu/drm/mxsfb/mxsfb_drv.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/mxsfb/mxsfb_drv.c b/drivers/gpu/drm/mxsfb/mxsfb_drv.c index ec0432fe1bdf8..86d78634a9799 100644 --- a/drivers/gpu/drm/mxsfb/mxsfb_drv.c +++ b/drivers/gpu/drm/mxsfb/mxsfb_drv.c @@ -173,7 +173,11 @@ static void mxsfb_irq_disable(struct drm_device *drm) struct mxsfb_drm_private *mxsfb = drm->dev_private;
mxsfb_enable_axi_clk(mxsfb);
- mxsfb->crtc.funcs->disable_vblank(&mxsfb->crtc);
- /* Disable and clear VBLANK IRQ */
- writel(CTRL1_CUR_FRAME_DONE_IRQ_EN, mxsfb->base + LCDC_CTRL1 + REG_CLR);
- writel(CTRL1_CUR_FRAME_DONE_IRQ, mxsfb->base + LCDC_CTRL1 + REG_CLR);
- mxsfb_disable_axi_clk(mxsfb);
}
-- 2.33.0
On 9/8/21 8:24 PM, Daniel Vetter wrote:
On Tue, Sep 07, 2021 at 04:49:00AM +0200, Marek Vasut wrote:
The mxsfb->crtc.funcs may already be NULL when unloading the driver, in which case calling mxsfb_irq_disable() via drm_irq_uninstall() from mxsfb_unload() leads to NULL pointer dereference.
Since all we care about is masking the IRQ and mxsfb->base is still valid, just use that to clear and mask the IRQ.
Fixes: ae1ed00932819 ("drm: mxsfb: Stop using DRM simple display pipeline helper") Signed-off-by: Marek Vasut marex@denx.de Cc: Daniel Abrecht public@danielabrecht.ch Cc: Emil Velikov emil.l.velikov@gmail.com Cc: Laurent Pinchart laurent.pinchart@ideasonboard.com Cc: Sam Ravnborg sam@ravnborg.org Cc: Stefan Agner stefan@agner.ch
You probably want a drm_atomic_helper_shutdown instead of trying to do all that manually. We've also added a bunch more devm and drmm_ functions to automate the cleanup a lot more here, e.g. your drm_mode_config_cleanup is in the wrong place.
Also I'm confused because I'm not even seeing this function anywhere in upstream.
It is still here: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/tree/dri... as of: 999569d59a0aa ("Add linux-next specific files for 20210908")
Is there some other tree I should be looking at ?
Hi Marek,
On Wed, Sep 08, 2021 at 08:24:20PM +0200, Daniel Vetter wrote:
On Tue, Sep 07, 2021 at 04:49:00AM +0200, Marek Vasut wrote:
The mxsfb->crtc.funcs may already be NULL when unloading the driver, in which case calling mxsfb_irq_disable() via drm_irq_uninstall() from mxsfb_unload() leads to NULL pointer dereference.
Since all we care about is masking the IRQ and mxsfb->base is still valid, just use that to clear and mask the IRQ.
Fixes: ae1ed00932819 ("drm: mxsfb: Stop using DRM simple display pipeline helper") Signed-off-by: Marek Vasut marex@denx.de Cc: Daniel Abrecht public@danielabrecht.ch Cc: Emil Velikov emil.l.velikov@gmail.com Cc: Laurent Pinchart laurent.pinchart@ideasonboard.com Cc: Sam Ravnborg sam@ravnborg.org Cc: Stefan Agner stefan@agner.ch
You probably want a drm_atomic_helper_shutdown instead of trying to do all that manually. We've also added a bunch more devm and drmm_ functions to automate the cleanup a lot more here, e.g. your drm_mode_config_cleanup is in the wrong place.
I have applied v2 of this patch today - but failed to see any response in v2 to this comment from Daniel. Was it lost somehow?
Sam
On 10/17/21 7:52 PM, Sam Ravnborg wrote:
Hi Marek,
On Wed, Sep 08, 2021 at 08:24:20PM +0200, Daniel Vetter wrote:
On Tue, Sep 07, 2021 at 04:49:00AM +0200, Marek Vasut wrote:
The mxsfb->crtc.funcs may already be NULL when unloading the driver, in which case calling mxsfb_irq_disable() via drm_irq_uninstall() from mxsfb_unload() leads to NULL pointer dereference.
Since all we care about is masking the IRQ and mxsfb->base is still valid, just use that to clear and mask the IRQ.
Fixes: ae1ed00932819 ("drm: mxsfb: Stop using DRM simple display pipeline helper") Signed-off-by: Marek Vasut marex@denx.de Cc: Daniel Abrecht public@danielabrecht.ch Cc: Emil Velikov emil.l.velikov@gmail.com Cc: Laurent Pinchart laurent.pinchart@ideasonboard.com Cc: Sam Ravnborg sam@ravnborg.org Cc: Stefan Agner stefan@agner.ch
You probably want a drm_atomic_helper_shutdown instead of trying to do all that manually. We've also added a bunch more devm and drmm_ functions to automate the cleanup a lot more here, e.g. your drm_mode_config_cleanup is in the wrong place.
I have applied v2 of this patch today - but failed to see any response in v2 to this comment from Daniel. Was it lost somehow?
Hmmm, I'll investigate that ^ in the next round of mxsfb clean ups.
On Sun, Oct 17, 2021 at 10:05 PM Marek Vasut marex@denx.de wrote:
On 10/17/21 7:52 PM, Sam Ravnborg wrote:
Hi Marek,
On Wed, Sep 08, 2021 at 08:24:20PM +0200, Daniel Vetter wrote:
On Tue, Sep 07, 2021 at 04:49:00AM +0200, Marek Vasut wrote:
The mxsfb->crtc.funcs may already be NULL when unloading the driver, in which case calling mxsfb_irq_disable() via drm_irq_uninstall() from mxsfb_unload() leads to NULL pointer dereference.
Since all we care about is masking the IRQ and mxsfb->base is still valid, just use that to clear and mask the IRQ.
Fixes: ae1ed00932819 ("drm: mxsfb: Stop using DRM simple display pipeline helper") Signed-off-by: Marek Vasut marex@denx.de Cc: Daniel Abrecht public@danielabrecht.ch Cc: Emil Velikov emil.l.velikov@gmail.com Cc: Laurent Pinchart laurent.pinchart@ideasonboard.com Cc: Sam Ravnborg sam@ravnborg.org Cc: Stefan Agner stefan@agner.ch
You probably want a drm_atomic_helper_shutdown instead of trying to do all that manually. We've also added a bunch more devm and drmm_ functions to automate the cleanup a lot more here, e.g. your drm_mode_config_cleanup is in the wrong place.
I have applied v2 of this patch today - but failed to see any response in v2 to this comment from Daniel. Was it lost somehow?
Hmmm, I'll investigate that ^ in the next round of mxsfb clean ups.
Yeah this was just a quick comment about how to do this cleanly, not meant to hold up a bugfix or anything like that. -Daniel
dri-devel@lists.freedesktop.org
-
Daniel Vetter -
Marek Vasut -
Sam Ravnborg