Messages in this thread | | | Date | Thu, 10 Apr 2008 08:01:37 -0700 | From | Randy Dunlap <> | Subject | Re: debug Kconfig option (was Re: linux-next: Tree for April 9) |
| |
On Thu, 10 Apr 2008 09:52:25 +0200 (CEST) Stefan Richter wrote:
> On 10 Apr, Stephen Rothwell wrote: > > On Thu, 10 Apr 2008 08:52:27 +0200 Ingo Molnar <mingo@elte.hu> wrote: > >> > >> what type of conflict do you have there? If it's a new entry then you > >> might be able to fix it by moving the new entry elsewhere in the file. > >> Or if i introduced a new entry close to an existing entry you modify > >> then i could move my new entry elsewhere. > > > > Commit 523a65f1a7a339e528ca6d6d808516fe195fde03 ("firewire: fw-ohci: add > > option for remote debugging") in the ieee1394 tree adds a new entry just > > where the sched tree adds > > > > source kernel/trace/Kconfig > > > > I grab this opportunity to ask the list: Would you prefer the remote > debugging option in the kernel hacking menu (as in the commit), or > rather in the respective driver submenu?
I like it in the kernel hacking menu.
> For reference: > > Date: Thu, 28 Feb 2008 20:54:43 +0100 (CET) > From: Stefan Richter <stefanr@s5r6.in-berlin.de> > Subject: firewire: fw-ohci: add option for remote debugging > > This way firewire-ohci can be used for remote debugging like ohci1394. > > Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> > --- > Documentation/debugging-via-ohci1394.txt | 13 ++++++++----- > drivers/firewire/fw-ohci.c | 9 +++++++++ > lib/Kconfig.debug | 10 ++++++++++ > 3 files changed, 27 insertions(+), 5 deletions(-) > > Index: linux/Documentation/debugging-via-ohci1394.txt > =================================================================== > --- linux.orig/Documentation/debugging-via-ohci1394.txt > +++ linux/Documentation/debugging-via-ohci1394.txt > @@ -41,11 +41,14 @@ to a working state and enables physical > This can be turned off by ohci1394's module parameter phys_dma=0. > > The alternative firewire-ohci driver in drivers/firewire uses filtered physical > -DMA, hence is not yet suitable for remote debugging. > - > -Because ohci1394 depends on the PCI enumeration to be completed, an > -initialization routine which runs pretty early (long before console_init() > -which makes the printk buffer appear on the console can be called) was written. > +DMA by default, which is more secure but not suitable for remote debugging. > +Compile the driver with CONFIG_FIREWIRE_OHCI_REMOTE_DMA to get unfiltered > +physical DMA. > + > +Because ohci1394 and firewire-ohci depend on the PCI enumeration to be > +completed, an initialization routine which runs pretty early has been > +implemented for x86. This routine runs long before console_init() can be > +called, i.e. before the printk buffer appears on the console. > > To activate it, enable CONFIG_PROVIDE_OHCI1394_DMA_INIT (Kernel hacking menu: > Provide code for enabling DMA over FireWire early on boot) and pass the > Index: linux/drivers/firewire/fw-ohci.c > =================================================================== > --- linux.orig/drivers/firewire/fw-ohci.c > +++ linux/drivers/firewire/fw-ohci.c > @@ -1097,6 +1097,11 @@ static void bus_reset_tasklet(unsigned l > reg_write(ohci, OHCI1394_ConfigROMhdr, ohci->next_header); > } > > +#ifdef CONFIG_FIREWIRE_OHCI_REMOTE_DMA > + reg_write(ohci, OHCI1394_PhyReqFilterHiSet, ~0); > + reg_write(ohci, OHCI1394_PhyReqFilterLoSet, ~0); > +#endif > + > spin_unlock_irqrestore(&ohci->lock, flags); > > if (free_rom) > @@ -1435,6 +1440,9 @@ static int ohci_cancel_packet(struct fw_ > static int > ohci_enable_phys_dma(struct fw_card *card, int node_id, int generation) > { > +#ifdef CONFIG_FIREWIRE_OHCI_REMOTE_DMA > + return 0; > +#else > struct fw_ohci *ohci = fw_ohci(card); > unsigned long flags; > int n, retval = 0; > @@ -1466,6 +1474,7 @@ ohci_enable_phys_dma(struct fw_card *car > out: > spin_unlock_irqrestore(&ohci->lock, flags); > return retval; > +#endif /* CONFIG_FIREWIRE_OHCI_REMOTE_DMA */ > } > > static u64 > Index: linux/lib/Kconfig.debug > =================================================================== > --- linux.orig/lib/Kconfig.debug > +++ linux/lib/Kconfig.debug > @@ -592,6 +592,16 @@ config LATENCYTOP > Enable this option if you want to use the LatencyTOP tool > to find out which userspace is blocking on what kernel operations. > > +config FIREWIRE_OHCI_REMOTE_DMA > + bool "Remote debugging via firewire-ohci" > + depends on FIREWIRE_OHCI > + help > + This option lets you use the FireWire bus for remote debugging. > + It enables unfiltered remote DMA in the firewire-ohci driver. > + See Documentation/debugging-via-ohci1394.txt for more information. > + > + If unsure, say N. > + > config PROVIDE_OHCI1394_DMA_INIT > bool "Provide code for enabling DMA over FireWire early on boot" > depends on PCI && X86 > > --
--- ~Randy
| |