On Tue 27 Aug 13:25 PDT 2019, Suman Anna wrote: > Hi Bjorn, > > On 8/27/19 12:10 AM, Bjorn Andersson wrote: > > On Fri 09 Aug 13:25 PDT 2019, Suman Anna wrote: > > > >> Hi Bjorn, > >> > > > > Hi Suman > > > >> On 10/23/18 8:19 PM, Suman Anna wrote: > >>> The virtio_rpmsg_bus driver uses the "%p" format-specifier for > >>> printing the vring buffer address. This prints only a hashed > >>> pointer even for previliged users. Use "%pK" instead so that > >>> the address can be printed during debug using kptr_restrict > >>> sysctl. > >> > >> Seems to have been lost among the patches, can you pick up this trivial > >> patch for 5.4? Should apply cleanly on the latest HEAD as well. > >> > > > > I share Andrew's question regarding what benefit you have from knowing > > this value. Should we not just remove the va from the print? Or do you > > actually have a use case for it?. > > I mainly use it during debug when comparing against kernel_page_tables > and vmallocinfo. The pools that we use are not always guaranteed to be > from linear memory, and behavior changes when using with CMA or DMA pools. > Thanks Suman. It seems to me that there's room for improvement to aid this kind of debugging. But your usecase seems reasonable, so I'm merging the patch. > Note that usage of %pK does not leak the addresses automatically, but > atleast enables me to get the values when needed. The changes also bring > the usage in rpmsg core in sync with the remoteproc core. > Sounds like shouldn't have merged them in remoteproc then ;P Thanks, Bjorn > regards > Suman > > > > > Regards, > > Bjorn > > > >> regards > >> Suman > >> > >>> > >>> Signed-off-by: Suman Anna <s-anna@xxxxxx> > >>> --- > >>> drivers/rpmsg/virtio_rpmsg_bus.c | 2 +- > >>> 1 file changed, 1 insertion(+), 1 deletion(-) > >>> > >>> diff --git a/drivers/rpmsg/virtio_rpmsg_bus.c b/drivers/rpmsg/virtio_rpmsg_bus.c > >>> index f29dee731026..1345f373a1a0 100644 > >>> --- a/drivers/rpmsg/virtio_rpmsg_bus.c > >>> +++ b/drivers/rpmsg/virtio_rpmsg_bus.c > >>> @@ -950,7 +950,7 @@ static int rpmsg_probe(struct virtio_device *vdev) > >>> goto vqs_del; > >>> } > >>> > >>> - dev_dbg(&vdev->dev, "buffers: va %p, dma %pad\n", > >>> + dev_dbg(&vdev->dev, "buffers: va %pK, dma %pad\n", > >>> bufs_va, &vrp->bufs_dma); > >>> > >>> /* half of the buffers is dedicated for RX */ > >>> > >> >
