On 30.07.2017 20:37, James Bottomley wrote:
> On Sun, 2017-07-30 at 14:21 -0400, John David Anglin wrote:
>> On 2017-07-30, at 2:12 PM, Meelis Roos wrote:
>>
>>>
>>>>
>>>> How about this? There's no need to take the write lock when
>>>> creating
>>>> links anyway.
>>>
>>> No effect.
>>
>> Is the backtrace still the same?
>
> There's another write lock over a symlink in
> pdcs_register_pathentries() does moving it up as well finally make this
> go away (cumulative patch below). If that doesn't work, enabling
> DEBUG_PREEMPT might show which lock is the problem.
That patch works.
Helge
> diff --git a/drivers/parisc/pdc_stable.c b/drivers/parisc/pdc_stable.c
> index 7147aa53e9a2..3e0c90420a1b 100644
> --- a/drivers/parisc/pdc_stable.c
> +++ b/drivers/parisc/pdc_stable.c
> @@ -331,13 +331,13 @@ pdcspath_hwpath_write(struct pdcspath_entry *entry, const char *buf, size_t coun
> /* Now, dive in. Write back to the hardware */
> pdcspath_store(entry);
>
> + write_unlock(&entry->rw_lock);
> +
> /* Update the symlink to the real device */
> sysfs_remove_link(&entry->kobj, "device");
> ret = sysfs_create_link(&entry->kobj, &entry->dev->kobj, "device");
> WARN_ON(ret);
>
> - write_unlock(&entry->rw_lock);
> -
> printk(KERN_INFO PDCS_PREFIX ": changed \"%s\" path to \"%s\"\n",
> entry->name, buf);
>
> @@ -998,6 +998,7 @@ pdcs_register_pathentries(void)
> /* kobject is now registered */
> write_lock(&entry->rw_lock);
> entry->ready = 2;
> + write_unlock(&entry->rw_lock);
>
> /* Add a nice symlink to the real device */
> if (entry->dev) {
> @@ -1005,7 +1006,6 @@ pdcs_register_pathentries(void)
> WARN_ON(err);
> }
>
> - write_unlock(&entry->rw_lock);
> kobject_uevent(&entry->kobj, KOBJ_ADD);
> }
>
>
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-parisc" in
> the body of a message to majordomo@xxxxxxxxxxxxxxx
> More majordomo info at http://vger.kernel.org/majordomo-info.html
>
--
To unsubscribe from this list: send the line "unsubscribe linux-parisc" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
