6.12-stable review patch. If anyone has any objections, please let me know.
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From: Vladimir Zapolskiy vladimir.zapolskiy@linaro.org
commit 4f45d65b781499d2a79eca12155532739c876aa2 upstream.
There is a chance to meet runtime issues during configuration of CAMSS power domains, because on the error path dev_pm_domain_detach() is unexpectedly called with NULL or error pointer.
One of the simplest ways to reproduce the problem is to probe CAMSS driver before registration of CAMSS power domains, for instance if a platform CAMCC driver is simply not built.
Warning backtrace example:
Unable to handle kernel NULL pointer dereference at virtual address 00000000000001a2
<snip>
pc : dev_pm_domain_detach+0x8/0x48 lr : camss_probe+0x374/0x9c0
<snip>
Call trace: dev_pm_domain_detach+0x8/0x48 platform_probe+0x70/0xf0 really_probe+0xc4/0x2a8 __driver_probe_device+0x80/0x140 driver_probe_device+0x48/0x170 __device_attach_driver+0xc0/0x148 bus_for_each_drv+0x88/0xf0 __device_attach+0xb0/0x1c0 device_initial_probe+0x1c/0x30 bus_probe_device+0xb4/0xc0 deferred_probe_work_func+0x90/0xd0 process_one_work+0x164/0x3e0 worker_thread+0x310/0x420 kthread+0x120/0x130 ret_from_fork+0x10/0x20
Fixes: 23aa4f0cd327 ("media: qcom: camss: Move VFE power-domain specifics into vfe.c") Cc: stable@vger.kernel.org Signed-off-by: Vladimir Zapolskiy vladimir.zapolskiy@linaro.org Reviewed-by: Bryan O'Donoghue bryan.odonoghue@linaro.org Signed-off-by: Hans Verkuil hverkuil-cisco@xs4all.nl Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/media/platform/qcom/camss/camss.c | 19 ++++++++----------- 1 file changed, 8 insertions(+), 11 deletions(-)
--- a/drivers/media/platform/qcom/camss/camss.c +++ b/drivers/media/platform/qcom/camss/camss.c @@ -2130,10 +2130,8 @@ static int camss_configure_pd(struct cam if (camss->res->pd_name) { camss->genpd = dev_pm_domain_attach_by_name(camss->dev, camss->res->pd_name); - if (IS_ERR(camss->genpd)) { - ret = PTR_ERR(camss->genpd); - goto fail_pm; - } + if (IS_ERR(camss->genpd)) + return PTR_ERR(camss->genpd); }
if (!camss->genpd) { @@ -2143,14 +2141,13 @@ static int camss_configure_pd(struct cam */ camss->genpd = dev_pm_domain_attach_by_id(camss->dev, camss->genpd_num - 1); + if (IS_ERR(camss->genpd)) + return PTR_ERR(camss->genpd); } - if (IS_ERR_OR_NULL(camss->genpd)) { - if (!camss->genpd) - ret = -ENODEV; - else - ret = PTR_ERR(camss->genpd); - goto fail_pm; - } + + if (!camss->genpd) + return -ENODEV; + camss->genpd_link = device_link_add(camss->dev, camss->genpd, DL_FLAG_STATELESS | DL_FLAG_PM_RUNTIME | DL_FLAG_RPM_ACTIVE);