On Thu, Nov 17, 2022 at 04:05:24PM -0800, Ira wrote: > From: Ira Weiny <ira.weiny@xxxxxxxxx> Sorry about the extra pre-patches listed below. They are not needed. > > Work item initialization needs to be done with either > INIT_WORK_ONSTACK() or INIT_WORK() depending on how the work item is > allocated. > > The callers of pci_doe_submit_task() allocate struct pci_doe_task on the > stack and pci_doe_submit_task() incorrectly used INIT_WORK(). > > Jonathan suggested creating doe task allocation macros such as > DECLARE_CDAT_DOE_TASK_ONSTACK().[1] The issue with this is the work > function is not known to the callers and must be initialized correctly. > > A follow up suggestion was to have an internal 'pci_doe_work' item > allocated by pci_doe_submit_task().[2] This requires an allocation which > could restrict the context where tasks are used. > > Another idea was to have an intermediate step to initialize the task > struct with a new call.[3] This added a lot of complexity. > > Lukas pointed out that object_is_on_stack() is available to detect this > automatically. > > Use object_is_on_stack() to determine the correct init work function to > call. > > [1] https://lore.kernel.org/linux-cxl/20221014151045.24781-1-Jonathan.Cameron@xxxxxxxxxx/T/#m88a7f50dcce52f30c8bf5c3dcc06fa9843b54a2d > [2] https://lore.kernel.org/linux-cxl/20221014151045.24781-1-Jonathan.Cameron@xxxxxxxxxx/T/#m63c636c5135f304480370924f4d03c00357be667 > [3] https://lore.kernel.org/all/20221115011943.1051039-1-ira.weiny@xxxxxxxxx/ > > Cc: Bjorn Helgaas <helgaas@xxxxxxxxxx> > Cc: Dan Williams <dan.j.williams@xxxxxxxxx> > Reported-by: Gregory Price <gregory.price@xxxxxxxxxxxx> > Reported-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx> > Suggested-by: Lukas Wunner <lukas@xxxxxxxxx> > Signed-off-by: Ira Weiny <ira.weiny@xxxxxxxxx> > > --- > Changes from V1 > Update oneliner > Use object_is_on_stack() to make this a simple fix > --- > drivers/pci/doe.c | 6 +++++- > 1 file changed, 5 insertions(+), 1 deletion(-) > > diff --git a/drivers/pci/doe.c b/drivers/pci/doe.c > index e402f05068a5..42de517022d9 100644 > --- a/drivers/pci/doe.c > +++ b/drivers/pci/doe.c > @@ -19,6 +19,7 @@ > #include <linux/pci.h> > #include <linux/pci-doe.h> > #include <linux/workqueue.h> > +#include <linux/sched/task_stack.h> > > #define PCI_DOE_PROTOCOL_DISCOVERY 0 > > @@ -529,7 +530,10 @@ int pci_doe_submit_task(struct pci_doe_mb *doe_mb, struct pci_doe_task *task) > return -EIO; > > task->doe_mb = doe_mb; > - INIT_WORK(&task->work, doe_statemachine_work); > + if (object_is_on_stack(&task->work)) > + INIT_WORK_ONSTACK(&task->work, doe_statemachine_work); > + else > + INIT_WORK(&task->work, doe_statemachine_work); > queue_work(doe_mb->work_queue, &task->work); > return 0; > } > > base-commit: 30a0b95b1335e12efef89dd78518ed3e4a71a763 This is correct. > prerequisite-patch-id: dfea657e07f37aa9d7c3d477d68b07f64fe78721 > prerequisite-patch-id: e27264e76e637214ee50cdab0e5854b223d44b4e These are not needed... Sorry, should I resend? Ira > -- > 2.37.2 >
