| Message ID | 1394038675-15809-2-git-send-email-alexandre.belloni@free-electrons.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 05/03/14 16:57, Alexandre Belloni wrote: > Trying to use the at91_adc driver while not using device tree is ending up in a > kernel crash: > > Unable to handle kernel NULL pointer dereference at virtual address 00000004 > [...] > [<c01f3510>] (at91_adc_probe) from [<c0183828>] (platform_drv_probe+0x18/0x48) > [<c0183828>] (platform_drv_probe) from [<c01824a4>] (driver_probe_device+0x100/0x218) > [<c01824a4>] (driver_probe_device) from [<c0182648>] (__driver_attach+0x8c/0x90) > [<c0182648>] (__driver_attach) from [<c0180de4>] (bus_for_each_dev+0x58/0x88) > [<c0180de4>] (bus_for_each_dev) from [<c0181c7c>] (bus_add_driver+0xd4/0x1d4) > [<c0181c7c>] (bus_add_driver) from [<c0182c40>] (driver_register+0x78/0xf4) > [<c0182c40>] (driver_register) from [<c0008998>] (do_one_initcall+0xe8/0x14c) > [<c0008998>] (do_one_initcall) from [<c02f0b50>] (kernel_init_freeable+0xec/0x1b4) > [<c02f0b50>] (kernel_init_freeable) from [<c022acdc>] (kernel_init+0x8/0xe4) > [<c022acdc>] (kernel_init) from [<c0009670>] (ret_from_fork+0x14/0x24) > > This is because the at91_adc_caps structure is mandatory but is not filled when > using platform_data. Correct that by using an id_table. It ensues that the > driver will not match "at91_adc" anymore but it was crashing anyway. > > Fixes: c46016665fff (iio: at91: ADC start-up time calculation changed since at91sam9x5) > Cc: stable@vger.kernel.org # v3.13+ > > Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com> Ouch. It's late in the cycle so I'll send this on to Greg KH with a note to say either send it to Linus if he is happy doing so - or send it early in 3.15, then it'll get picked up for stable. I'll give it a day or so to see if I the at91 maintainers are happy with the other two parts as it is probably cleaner if all 3 go together. Applied to the fixes-togreg branch of iio.git Thanks, Jonathan > --- > drivers/iio/adc/at91_adc.c | 26 ++++++++++++++++++++++---- > 1 file changed, 22 insertions(+), 4 deletions(-) > > diff --git a/drivers/iio/adc/at91_adc.c b/drivers/iio/adc/at91_adc.c > index 5b1aa027c034..bbba014c9939 100644 > --- a/drivers/iio/adc/at91_adc.c > +++ b/drivers/iio/adc/at91_adc.c > @@ -765,14 +765,17 @@ static int at91_adc_probe_pdata(struct at91_adc_state *st, > if (!pdata) > return -EINVAL; > > + st->caps = (struct at91_adc_caps *) > + platform_get_device_id(pdev)->driver_data; > + > st->use_external = pdata->use_external_triggers; > st->vref_mv = pdata->vref; > st->channels_mask = pdata->channels_used; > - st->num_channels = pdata->num_channels; > + st->num_channels = st->caps->num_channels; > st->startup_time = pdata->startup_time; > st->trigger_number = pdata->trigger_number; > st->trigger_list = pdata->trigger_list; > - st->registers = pdata->registers; > + st->registers = &st->caps->registers; > > return 0; > } > @@ -1101,7 +1104,6 @@ static int at91_adc_remove(struct platform_device *pdev) > return 0; > } > > -#ifdef CONFIG_OF > static struct at91_adc_caps at91sam9260_caps = { > .calc_startup_ticks = calc_startup_ticks_9260, > .num_channels = 4, > @@ -1154,11 +1156,27 @@ static const struct of_device_id at91_adc_dt_ids[] = { > {}, > }; > MODULE_DEVICE_TABLE(of, at91_adc_dt_ids); > -#endif > + > +static const struct platform_device_id at91_adc_ids[] = { > + { > + .name = "at91sam9260-adc", > + .driver_data = (unsigned long)&at91sam9260_caps, > + }, { > + .name = "at91sam9g45-adc", > + .driver_data = (unsigned long)&at91sam9g45_caps, > + }, { > + .name = "at91sam9x5-adc", > + .driver_data = (unsigned long)&at91sam9x5_caps, > + }, { > + /* terminator */ > + } > +}; > +MODULE_DEVICE_TABLE(platform, at91_adc_ids); > > static struct platform_driver at91_adc_driver = { > .probe = at91_adc_probe, > .remove = at91_adc_remove, > + .id_table = at91_adc_ids, > .driver = { > .name = DRIVER_NAME, > .of_match_table = of_match_ptr(at91_adc_dt_ids), >
Hi Jonathan, On 06/03/2014 at 19:15:28 +0000, Jonathan Cameron wrote : > It's late in the cycle so I'll send this on to Greg KH with a note > to say either send it to Linus if he is happy doing so - or send > it early in 3.15, then it'll get picked up for stable. > > I'll give it a day or so to see if I the at91 maintainers are happy > with the other two parts as it is probably cleaner if all 3 go together. > > Applied to the fixes-togreg branch of iio.git > I don't recall seeing you sending that to Greg. Could you do that, along with the two other patches that got acked by Nicolas ? Anyway, if it is too late, we'll push for stable. Thanks !
On March 12, 2014 10:57:46 AM GMT+00:00, Alexandre Belloni <alexandre.belloni@free-electrons.com> wrote: >Hi Jonathan, > >On 06/03/2014 at 19:15:28 +0000, Jonathan Cameron wrote : >> It's late in the cycle so I'll send this on to Greg KH with a note >> to say either send it to Linus if he is happy doing so - or send >> it early in 3.15, then it'll get picked up for stable. >> >> I'll give it a day or so to see if I the at91 maintainers are happy >> with the other two parts as it is probably cleaner if all 3 go >together. >> >> Applied to the fixes-togreg branch of iio.git >> > >I don't recall seeing you sending that to Greg. Could you do that, >along >with the two other patches that got acked by Nicolas ? Sorry spot of man flu, messy weekend and manic day job have made for an interesting week. Given regression has already snuck out in a release and Greg doesn't have other fixes queued I think we are talking soon after merge window and rc1. I'll check with Greg though... > >Anyway, if it is too late, we'll push for stable. > >Thanks !
diff --git a/drivers/iio/adc/at91_adc.c b/drivers/iio/adc/at91_adc.c index 5b1aa027c034..bbba014c9939 100644 --- a/drivers/iio/adc/at91_adc.c +++ b/drivers/iio/adc/at91_adc.c @@ -765,14 +765,17 @@ static int at91_adc_probe_pdata(struct at91_adc_state *st, if (!pdata) return -EINVAL; + st->caps = (struct at91_adc_caps *) + platform_get_device_id(pdev)->driver_data; + st->use_external = pdata->use_external_triggers; st->vref_mv = pdata->vref; st->channels_mask = pdata->channels_used; - st->num_channels = pdata->num_channels; + st->num_channels = st->caps->num_channels; st->startup_time = pdata->startup_time; st->trigger_number = pdata->trigger_number; st->trigger_list = pdata->trigger_list; - st->registers = pdata->registers; + st->registers = &st->caps->registers; return 0; } @@ -1101,7 +1104,6 @@ static int at91_adc_remove(struct platform_device *pdev) return 0; } -#ifdef CONFIG_OF static struct at91_adc_caps at91sam9260_caps = { .calc_startup_ticks = calc_startup_ticks_9260, .num_channels = 4, @@ -1154,11 +1156,27 @@ static const struct of_device_id at91_adc_dt_ids[] = { {}, }; MODULE_DEVICE_TABLE(of, at91_adc_dt_ids); -#endif + +static const struct platform_device_id at91_adc_ids[] = { + { + .name = "at91sam9260-adc", + .driver_data = (unsigned long)&at91sam9260_caps, + }, { + .name = "at91sam9g45-adc", + .driver_data = (unsigned long)&at91sam9g45_caps, + }, { + .name = "at91sam9x5-adc", + .driver_data = (unsigned long)&at91sam9x5_caps, + }, { + /* terminator */ + } +}; +MODULE_DEVICE_TABLE(platform, at91_adc_ids); static struct platform_driver at91_adc_driver = { .probe = at91_adc_probe, .remove = at91_adc_remove, + .id_table = at91_adc_ids, .driver = { .name = DRIVER_NAME, .of_match_table = of_match_ptr(at91_adc_dt_ids),
Trying to use the at91_adc driver while not using device tree is ending up in a kernel crash: Unable to handle kernel NULL pointer dereference at virtual address 00000004 [...] [<c01f3510>] (at91_adc_probe) from [<c0183828>] (platform_drv_probe+0x18/0x48) [<c0183828>] (platform_drv_probe) from [<c01824a4>] (driver_probe_device+0x100/0x218) [<c01824a4>] (driver_probe_device) from [<c0182648>] (__driver_attach+0x8c/0x90) [<c0182648>] (__driver_attach) from [<c0180de4>] (bus_for_each_dev+0x58/0x88) [<c0180de4>] (bus_for_each_dev) from [<c0181c7c>] (bus_add_driver+0xd4/0x1d4) [<c0181c7c>] (bus_add_driver) from [<c0182c40>] (driver_register+0x78/0xf4) [<c0182c40>] (driver_register) from [<c0008998>] (do_one_initcall+0xe8/0x14c) [<c0008998>] (do_one_initcall) from [<c02f0b50>] (kernel_init_freeable+0xec/0x1b4) [<c02f0b50>] (kernel_init_freeable) from [<c022acdc>] (kernel_init+0x8/0xe4) [<c022acdc>] (kernel_init) from [<c0009670>] (ret_from_fork+0x14/0x24) This is because the at91_adc_caps structure is mandatory but is not filled when using platform_data. Correct that by using an id_table. It ensues that the driver will not match "at91_adc" anymore but it was crashing anyway. Fixes: c46016665fff (iio: at91: ADC start-up time calculation changed since at91sam9x5) Cc: stable@vger.kernel.org # v3.13+ Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com> --- drivers/iio/adc/at91_adc.c | 26 ++++++++++++++++++++++---- 1 file changed, 22 insertions(+), 4 deletions(-)