Re: [PATCH] clocksource: timer-ti-dm: Fix regression

[Keerthy]

On 11/01/20 11:58 am, Naresh Kamboju wrote:
> On Tue, 7 Jan 2020 at 02:07, Tony Lindgren <tony@xxxxxxxxxxx> wrote:
> > Clean-up commit 8c82723414d5 ("clocksource/drivers/timer-ti-dm: Switch to
> > platform_get_irq") caused a regression where we now try to access
> > uninitialized data for timer:
> >
> > drivers/clocksource/timer-ti-dm.c: In function 'omap_dm_timer_probe':
> > drivers/clocksource/timer-ti-dm.c:798:13: warning: 'timer' may be used
> > uninitialized in this function [-Wmaybe-uninitialized]
> >
> > On boot we now get:
> >
> > Unable to handle kernel NULL pointer dereference at virtual address
> > 00000004
> > ...
> > (omap_dm_timer_probe) from [<c061ac7c>] (platform_drv_probe+0x48/0x98)
> > (platform_drv_probe) from [<c0618c04>] (really_probe+0x1dc/0x348)
> > (really_probe) from [<c0618ef4>] (driver_probe_device+0x5c/0x160)
> >
> > Let's fix the issue by moving platform_get_irq to happen after timer has
> > been allocated.
> >
> > Fixes: 8c82723414d5 ("clocksource/drivers/timer-ti-dm: Switch to platform_get_irq")
>
> Thanks for fixing this issue.
> I have noticed arm BeagleBoard-X15 boot failed on linux next tree
> (5.5.0-rc5-next-20200110).
>
> [    6.157822] 8<--- cut here ---
> [    6.160911] Unable to handle kernel NULL pointer dereference at
> virtual address 00000004
> [    6.169120] pgd = 25d83e32
> [    6.171903] [00000004] *pgd=80000080204003, *pmd=00000000
> [    6.177358] Internal error: Oops: a06 [#1] SMP ARM
> [    6.182179] Modules linked in:
> [    6.185260] CPU: 0 PID: 1 Comm: swapper/0 Not tainted
> 5.5.0-rc5-next-20200110 #1
> [    6.192694] Hardware name: Generic DRA74X (Flattened Device Tree)
> [    6.198832] PC is at omap_dm_timer_probe+0x48/0x310

Tony/Daniel,

This is still not in linux-next. Any idea when this will be pushed to 
linux-next branch?

- Keerthy
> - Naresh