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

Keerthy
2020-01-16T03:46:09Z

On 11/01/20 11:58 am, Naresh Kamboju wrote:
> On Tue, 7 Jan 2020 at 02:07, Tony Lindgren <tony@atomide.com> 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
>