Kim Phillips <kim.phill...@arm.com> writes: > This patch is in the context of allowing the Coresight h/w > trace driver suite to be loaded as modules. Coresight uses > find_task_by_vpid when running in direct capture mode (via sysfs) > when getting/setting the context ID comparator to trigger on > (/sys/bus/coresight/devices/<x>.etm/ctxid_pid).
Nacked-by: "Eric W. Biederman" <ebied...@xmission.com> There is no way to implement a sysfs file that takes a pid correctly. Don't do it. Pids are tied to pid namespaces and sysfs deliberately does not do anything remotely resembly a pid namespace. Eric > Cc: Mathieu Poirier <mathieu.poir...@linaro.org> > Cc: Andrew Morton <a...@linux-foundation.org> > Cc: Oleg Nesterov <o...@redhat.com> > Cc: Gargi Sharma <gs051...@gmail.com> > Cc: Rik van Riel <r...@redhat.com> > Cc: Pavel Tatashin <pasha.tatas...@oracle.com> > Cc: Kefeng Wang <wangkefeng.w...@huawei.com> > Cc: Kirill Tkhai <ktk...@virtuozzo.com> > Cc: Mike Rapoport <r...@linux.vnet.ibm.com> > Cc: David Howells <dhowe...@redhat.com> > Cc: "Eric W. Biederman" <ebied...@xmission.com> > Signed-off-by: Kim Phillips <kim.phill...@arm.com> > --- > Current CoreSight callsite: > > https://lxr.missinglinkelectronics.com/linux/include/linux/coresight.h#L285 > > A quick look didn't find anything, but if Coresight needs to do > something differently, please comment. > > kernel/pid.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/kernel/pid.c b/kernel/pid.c > index 157fe4b19971..92b1b623f3e0 100644 > --- a/kernel/pid.c > +++ b/kernel/pid.c > @@ -342,6 +342,7 @@ struct task_struct *find_task_by_vpid(pid_t vnr) > { > return find_task_by_pid_ns(vnr, task_active_pid_ns(current)); > } > +EXPORT_SYMBOL_GPL(find_task_by_vpid); > > struct task_struct *find_get_task_by_vpid(pid_t nr) > {
