| Message ID | 20191025110450.10474-1-will@kernel.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm/radeon: Handle workqueue allocation failure | expand |
On 2019-10-25 1:04 p.m., Will Deacon wrote: > In the highly unlikely event that we fail to allocate the "radeon-crtc" > workqueue, we should bail cleanly rather than blindly march on with a > NULL pointer installed for the 'flip_queue' field of the 'radeon_crtc' > structure. > > This was reported previously by Nicolas, but I don't think his fix was > correct: Neither is this one I'm afraid. See my feedback on https://patchwork.freedesktop.org/patch/331534/ .
On Fri, Oct 25, 2019 at 06:06:26PM +0200, Michel Dänzer wrote: > On 2019-10-25 1:04 p.m., Will Deacon wrote: > > In the highly unlikely event that we fail to allocate the "radeon-crtc" > > workqueue, we should bail cleanly rather than blindly march on with a > > NULL pointer installed for the 'flip_queue' field of the 'radeon_crtc' > > structure. > > > > This was reported previously by Nicolas, but I don't think his fix was > > correct: > > Neither is this one I'm afraid. See my feedback on > https://patchwork.freedesktop.org/patch/331534/ . Thanks. Although I agree with you wrt the original patch, I don't think the workqueue allocation failure is distinguishable from the CRTC allocation failure with my patch. Are you saying that the error path there is broken too? Will
On 2019-10-25 6:18 p.m., Will Deacon wrote: > On Fri, Oct 25, 2019 at 06:06:26PM +0200, Michel Dänzer wrote: >> On 2019-10-25 1:04 p.m., Will Deacon wrote: >>> In the highly unlikely event that we fail to allocate the "radeon-crtc" >>> workqueue, we should bail cleanly rather than blindly march on with a >>> NULL pointer installed for the 'flip_queue' field of the 'radeon_crtc' >>> structure. >>> >>> This was reported previously by Nicolas, but I don't think his fix was >>> correct: >> >> Neither is this one I'm afraid. See my feedback on >> https://patchwork.freedesktop.org/patch/331534/ . > > Thanks. Although I agree with you wrt the original patch, I don't think > the workqueue allocation failure is distinguishable from the CRTC allocation > failure with my patch. Are you saying that the error path there is broken > too? The driver won't actually work if radeon_crtc_init bails silently, it'll just fall over at some later point.
On Fri, Oct 25, 2019 at 06:20:01PM +0200, Michel Dänzer wrote: > On 2019-10-25 6:18 p.m., Will Deacon wrote: > > On Fri, Oct 25, 2019 at 06:06:26PM +0200, Michel Dänzer wrote: > >> On 2019-10-25 1:04 p.m., Will Deacon wrote: > >>> In the highly unlikely event that we fail to allocate the "radeon-crtc" > >>> workqueue, we should bail cleanly rather than blindly march on with a > >>> NULL pointer installed for the 'flip_queue' field of the 'radeon_crtc' > >>> structure. > >>> > >>> This was reported previously by Nicolas, but I don't think his fix was > >>> correct: > >> > >> Neither is this one I'm afraid. See my feedback on > >> https://patchwork.freedesktop.org/patch/331534/ . > > > > Thanks. Although I agree with you wrt the original patch, I don't think > > the workqueue allocation failure is distinguishable from the CRTC allocation > > failure with my patch. Are you saying that the error path there is broken > > too? > > The driver won't actually work if radeon_crtc_init bails silently, it'll > just fall over at some later point. Ok, so how about fleshing it out as per below? Will --->8 diff --git a/drivers/gpu/drm/radeon/radeon_display.c b/drivers/gpu/drm/radeon/radeon_display.c index e81b01f8db90..177acee06620 100644 --- a/drivers/gpu/drm/radeon/radeon_display.c +++ b/drivers/gpu/drm/radeon/radeon_display.c @@ -668,21 +668,29 @@ static const struct drm_crtc_funcs radeon_crtc_funcs = { .page_flip_target = radeon_crtc_page_flip_target, }; -static void radeon_crtc_init(struct drm_device *dev, int index) +static int radeon_crtc_init(struct drm_device *dev, int index) { struct radeon_device *rdev = dev->dev_private; struct radeon_crtc *radeon_crtc; + struct workqueue_struct *wq; int i; radeon_crtc = kzalloc(sizeof(struct radeon_crtc) + (RADEONFB_CONN_LIMIT * sizeof(struct drm_connector *)), GFP_KERNEL); if (radeon_crtc == NULL) - return; + return -ENOMEM; + + wq = alloc_workqueue("radeon-crtc", WQ_HIGHPRI, 0); + if (unlikely(!wq)) { + kfree(radeon_crtc); + return - ENOMEM; + } drm_crtc_init(dev, &radeon_crtc->base, &radeon_crtc_funcs); drm_mode_crtc_set_gamma_size(&radeon_crtc->base, 256); radeon_crtc->crtc_id = index; - radeon_crtc->flip_queue = alloc_workqueue("radeon-crtc", WQ_HIGHPRI, 0); + radeon_crtc->flip_queue = wq; + rdev->mode_info.crtcs[index] = radeon_crtc; if (rdev->family >= CHIP_BONAIRE) { @@ -711,6 +719,8 @@ static void radeon_crtc_init(struct drm_device *dev, int index) radeon_atombios_init_crtc(dev, radeon_crtc); else radeon_legacy_init_crtc(dev, radeon_crtc); + + return 0; } static const char *encoder_names[38] = { @@ -1602,9 +1612,8 @@ int radeon_modeset_init(struct radeon_device *rdev) rdev->ddev->mode_config.fb_base = rdev->mc.aper_base; ret = radeon_modeset_create_props(rdev); - if (ret) { - return ret; - } + if (ret) + goto err_drm_mode_config_cleanup; /* init i2c buses */ radeon_i2c_init(rdev); @@ -1617,7 +1626,9 @@ int radeon_modeset_init(struct radeon_device *rdev) /* allocate crtcs */ for (i = 0; i < rdev->num_crtc; i++) { - radeon_crtc_init(rdev->ddev, i); + ret = radeon_crtc_init(rdev->ddev, i); + if (ret) + goto err_drm_mode_config_cleanup; } /* okay we should have all the bios connectors */ @@ -1645,6 +1656,10 @@ int radeon_modeset_init(struct radeon_device *rdev) ret = radeon_pm_late_init(rdev); return 0; + +err_drm_mode_config_cleanup: + drm_mode_config_cleanup(rdev->ddev); + return ret; } void radeon_modeset_fini(struct radeon_device *rdev)
diff --git a/drivers/gpu/drm/radeon/radeon_display.c b/drivers/gpu/drm/radeon/radeon_display.c index e81b01f8db90..3e4ef1380fca 100644 --- a/drivers/gpu/drm/radeon/radeon_display.c +++ b/drivers/gpu/drm/radeon/radeon_display.c @@ -672,17 +672,25 @@ static void radeon_crtc_init(struct drm_device *dev, int index) { struct radeon_device *rdev = dev->dev_private; struct radeon_crtc *radeon_crtc; + struct workqueue_struct *wq; int i; radeon_crtc = kzalloc(sizeof(struct radeon_crtc) + (RADEONFB_CONN_LIMIT * sizeof(struct drm_connector *)), GFP_KERNEL); if (radeon_crtc == NULL) return; + wq = alloc_workqueue("radeon-crtc", WQ_HIGHPRI, 0); + if (unlikely(!wq)) { + kfree(radeon_crtc); + return; + } + drm_crtc_init(dev, &radeon_crtc->base, &radeon_crtc_funcs); drm_mode_crtc_set_gamma_size(&radeon_crtc->base, 256); radeon_crtc->crtc_id = index; - radeon_crtc->flip_queue = alloc_workqueue("radeon-crtc", WQ_HIGHPRI, 0); + radeon_crtc->flip_queue = wq; + rdev->mode_info.crtcs[index] = radeon_crtc; if (rdev->family >= CHIP_BONAIRE) {
In the highly unlikely event that we fail to allocate the "radeon-crtc" workqueue, we should bail cleanly rather than blindly march on with a NULL pointer installed for the 'flip_queue' field of the 'radeon_crtc' structure. This was reported previously by Nicolas, but I don't think his fix was correct: Cc: Alex Deucher <alexander.deucher@amd.com> Cc: "Christian König" <christian.koenig@amd.com> Cc: "David (ChunMing) Zhou" <David1.Zhou@amd.com> Cc: David Airlie <airlied@linux.ie> Cc: Daniel Vetter <daniel@ffwll.ch> Reported-by: Nicolas Waisman <nico@semmle.com> Link: https://lore.kernel.org/lkml/CADJ_3a8WFrs5NouXNqS5WYe7rebFP+_A5CheeqAyD_p7DFJJcg@mail.gmail.com/ Signed-off-by: Will Deacon <will@kernel.org> --- Compile-tested only. drivers/gpu/drm/radeon/radeon_display.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-)