Hi Bjorn, On 1/10/20 10:23 PM, Mathieu Poirier wrote: > On Thu, Dec 26, 2019 at 09:32:13PM -0800, Bjorn Andersson wrote: >> Introduce a "panic" function in the remoteproc ops table, to allow >> remoteproc instances to perform operations needed in order to aid in >> post mortem system debugging, such as flushing caches etc, when the >> kernel panics. >> >> Signed-off-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx> >> --- >> >> Changes since v1: >> - None >> >> drivers/remoteproc/remoteproc_core.c | 17 +++++++++++++++++ >> include/linux/remoteproc.h | 4 ++++ >> 2 files changed, 21 insertions(+) >> >> diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c >> index 307df98347ba..779f19d6d8e7 100644 >> --- a/drivers/remoteproc/remoteproc_core.c >> +++ b/drivers/remoteproc/remoteproc_core.c >> @@ -1832,6 +1832,17 @@ void rproc_shutdown(struct rproc *rproc) >> } >> EXPORT_SYMBOL(rproc_shutdown); >> >> +static int rproc_panic_handler(struct notifier_block *nb, unsigned long event, >> + void *ptr) >> +{ >> + struct rproc *rproc = container_of(nb, struct rproc, panic_nb); >> + >> + if (rproc->state == RPROC_RUNNING) >> + rproc->ops->panic(rproc); >> + >> + return NOTIFY_DONE; >> +} >> + >> /** >> * rproc_get_by_phandle() - find a remote processor by phandle >> * @phandle: phandle to the rproc >> @@ -2057,6 +2068,12 @@ struct rproc *rproc_alloc(struct device *dev, const char *name, >> rproc->ops->get_boot_addr = rproc_elf_get_boot_addr; >> } >> >> + /* Register panic notifier for remoteprocs with "panic" callback */ >> + if (rproc->ops->panic) { >> + rproc->panic_nb.notifier_call = rproc_panic_handler; >> + atomic_notifier_chain_register(&panic_notifier_list, &rproc->panic_nb); > > Line over 80 characters. atomic_notifier_chain_unregister should be added in rproc_del. Regards, Arnaud > >> + } >> + >> mutex_init(&rproc->lock); >> >> idr_init(&rproc->notifyids); >> diff --git a/include/linux/remoteproc.h b/include/linux/remoteproc.h >> index 16ad66683ad0..7836c528d309 100644 >> --- a/include/linux/remoteproc.h >> +++ b/include/linux/remoteproc.h >> @@ -369,6 +369,7 @@ enum rsc_handling_status { >> * expects to find it >> * @sanity_check: sanity check the fw image >> * @get_boot_addr: get boot address to entry point specified in firmware >> + * @panic: optional callback to react to system panic >> */ >> struct rproc_ops { >> int (*start)(struct rproc *rproc); >> @@ -383,6 +384,7 @@ struct rproc_ops { >> int (*load)(struct rproc *rproc, const struct firmware *fw); >> int (*sanity_check)(struct rproc *rproc, const struct firmware *fw); >> u32 (*get_boot_addr)(struct rproc *rproc, const struct firmware *fw); >> + void (*panic)(struct rproc *rproc); >> }; >> >> /** >> @@ -481,6 +483,7 @@ struct rproc_dump_segment { >> * @auto_boot: flag to indicate if remote processor should be auto-started >> * @dump_segments: list of segments in the firmware >> * @nb_vdev: number of vdev currently handled by rproc >> + * @panic_nb: notifier_block for remoteproc's panic handler >> */ >> struct rproc { >> struct list_head node; >> @@ -514,6 +517,7 @@ struct rproc { >> bool auto_boot; >> struct list_head dump_segments; >> int nb_vdev; >> + struct notifier_block panic_nb; >> }; >> >> /** >> -- >> 2.24.0 >>