[PATCH] staging: tidspbridge: enable watchdog by default

[Greg KH]

On Thu, Feb 09, 2012 at 08:41:55PM +0200, Felipe Contreras wrote:
> On Thu, Feb 9, 2012 at 7:35 PM, Greg KH <gregkh at linuxfoundation.org> wrote:
> > On Wed, Feb 01, 2012 at 09:26:16AM +0200, Felipe Contreras wrote:
> >> On Wed, Feb 1, 2012 at 5:44 AM, Greg KH <greg at kroah.com> wrote:
> >> > On Wed, Feb 01, 2012 at 03:37:55AM +0200, Felipe Contreras wrote:
> >> >> On Wed, Feb 1, 2012 at 3:12 AM, Greg KH <gregkh at suse.de> wrote:
> >> >> > On Wed, Feb 01, 2012 at 03:01:32AM +0200, Felipe Contreras wrote:
> >> >> >> From: Felipe Contreras <felipe.contreras at nokia.com>
> >> >> >>
> >> >> >> The public images have it enabled, it's safer, and we get rid of this
> >> >> >> warning:
> >> >> >>
> >> >> >> WARNING: at arch/arm/mach-omap2/omap_l3_smx.c:162 omap3_l3_app_irq+0x114/0x15c()
> >> >> >> In-band Error seen by IVA_SS  at address 0
> >> >> >> Modules linked in: bridgedriver(C+) mailbox_mach mailbox ipv6 g_ether
> >> >> >> [<c0012848>] (unwind_backtrace+0x0/0xec) from [<c002e760>] (warn_slowpath_common+0x4c/0x64)
> >> >> >> [<c002e760>] (warn_slowpath_common+0x4c/0x64) from [<c002e7f8>] (warn_slowpath_fmt+0x2c/0x3c)
> >> >> >> [<c002e7f8>] (warn_slowpath_fmt+0x2c/0x3c) from [<c00217c8>] (omap3_l3_app_irq+0x114/0x15c)
> >> >> >> [<c00217c8>] (omap3_l3_app_irq+0x114/0x15c) from [<c0059844>] (handle_irq_event_percpu+0x28/0x174)
> >> >> >> [<c0059844>] (handle_irq_event_percpu+0x28/0x174) from [<c00599b8>] (handle_irq_event+0x28/0x38)
> >> >> >> [<c00599b8>] (handle_irq_event+0x28/0x38) from [<c005b8d0>] (handle_level_irq+0xb8/0xe0)
> >> >> >> [<c005b8d0>] (handle_level_irq+0xb8/0xe0) from [<c0059598>] (generic_handle_irq+0x28/0x30)
> >> >> >> [<c0059598>] (generic_handle_irq+0x28/0x30) from [<c000e62c>] (handle_IRQ+0x60/0x84)
> >> >> >> [<c000e62c>] (handle_IRQ+0x60/0x84) from [<c000d334>] (__irq_svc+0x34/0x80)
> >> >> >> [<c000d334>] (__irq_svc+0x34/0x80) from [<c0015804>] (v7_dma_inv_range+0x34/0x48)
> >> >> >> [<c0015804>] (v7_dma_inv_range+0x34/0x48) from [<c00129ec>] (dma_cache_maint_page+0x2c/0x34)
> >> >> >> [<c00129ec>] (dma_cache_maint_page+0x2c/0x34) from [<c0012a34>] (___dma_page_dev_to_cpu+0x24/0x68)
> >> >> >> [<c0012a34>] (___dma_page_dev_to_cpu+0x24/0x68) from [<c0012b50>] (dma_unmap_sg+0x40/0x64)
> >> >> >> [<c0012b50>] (dma_unmap_sg+0x40/0x64) from [<c019fba4>] (omap_hsmmc_post_req+0x3c/0x48)
> >> >> >> [<c019fba4>] (omap_hsmmc_post_req+0x3c/0x48) from [<c01932f4>] (mmc_post_req+0x18/0x1c)
> >> >> >> [<c01932f4>] (mmc_post_req+0x18/0x1c) from [<c019535c>] (mmc_start_req+0xd4/0xec)
> >> >> >> [<c019535c>] (mmc_start_req+0xd4/0xec) from [<c019d330>] (mmc_blk_issue_rw_rq+0x64/0x244)
> >> >> >> [<c019d330>] (mmc_blk_issue_rw_rq+0x64/0x244) from [<c019d7bc>] (mmc_blk_issue_rq+0x2ac/0x2cc)
> >> >> >> [<c019d7bc>] (mmc_blk_issue_rq+0x2ac/0x2cc) from [<c019e1c0>] (mmc_queue_thread+0x8c/0xf8)
> >> >> >> [<c019e1c0>] (mmc_queue_thread+0x8c/0xf8) from [<c0044c10>] (kthread+0x84/0x8c)
> >> >> >> [<c0044c10>] (kthread+0x84/0x8c) from [<c000e694>] (kernel_thread_exit+0x0/0x8)
> >> >> >> ---[ end trace 5dec1c8d7857375d ]---
> >> >> >>
> >> >> >> Signed-off-by: Felipe Contreras <felipe.contreras at nokia.com>
> >> >> >> ---
> >> >> >>  drivers/staging/tidspbridge/Kconfig |    1 +
> >> >> >>  1 files changed, 1 insertions(+), 0 deletions(-)
> >> >> >>
> >> >> >> diff --git a/drivers/staging/tidspbridge/Kconfig b/drivers/staging/tidspbridge/Kconfig
> >> >> >> index 21a559e..614e974 100644
> >> >> >> --- a/drivers/staging/tidspbridge/Kconfig
> >> >> >> +++ b/drivers/staging/tidspbridge/Kconfig
> >> >> >> @@ -61,6 +61,7 @@ config TIDSPBRIDGE_CACHE_LINE_CHECK
> >> >> >>  config TIDSPBRIDGE_WDT3
> >> >> >>       bool "Enable watchdog timer"
> >> >> >>       depends on TIDSPBRIDGE
> >> >> >> +     default y
> >> >> >
> >> >> > Nothing is ever default y, sorry, I can't accept this.
> >> >>
> >> >> % git grep 'default y' -- 'drivers/*/Kconfig' | wc -l
> >> >> 493
> >> >
> >> > That's nice, but proves nothing, no new entries should be y.
> >> >
> >> > If it should be y, then it should just not be an option and always
> >> > enabled, right?  Why not do that?
> >>
> >> What if I compiled a DSP baseimage that doesn't have this watchdog?
> >
> > I don't know, you tell me.
> 
> Then you want this option disabled.
> 
> >> And using that logic, we should start removing all configurations in
> >> the kernel that have 'default y'.
> >
> > If your machine needs it to boot, then no, do not.
> 
> There's many configurations that are not needed for booting, yet they
> are 'default y'.

Again, for historical reasons, yes, but do you see that happening for
"new" code these days?

And if it does get set to 'y' for new code, you have seen the yelling,
right?

Again, I'm totally confused as to _WHY_ this needs to be y.  What is
causing this oops without it?  If an oops is happening, then shouldn't
this be a strict dependancy?  Why allow it to be disabled at all if it
can break your box if you don't enable it?

thanks,

greg k-h