[PATCH] tmio_mmc: fix misuse of kunmap_atomic() in tmio_mmc.c

[Eric Miao]

On Sun, Aug 15, 2010 at 4:33 AM, Guennadi Liakhovetski
<g.liakhovetski at gmx.de> wrote:
> Hi Eric
>
> On Thu, 12 Aug 2010, Eric Miao wrote:
>
>> According to commit 597781f3e51f48ef8e67be772196d9e9673752c4
>>
>>     kmap_atomic: make kunmap_atomic() harder to misuse
>>
>> kunmap_atomic() takes a pointer to within the page, instead of a pointer
>> to 'struct page'.  So tmio_mmc_kunmap_atomic() should really take the
>> pointer what tmio_mmc_kmap_atomic() returns.
>
> As you have seen, I've also prepared a fix for this problem, just haven't
> sent it fast enough;) And, I think, your fix isn't quite correct: "buf" is
> not the returned value from tmio_mmc_kmap_atomic(), so, you cannot use it
> for unmapping.
>

Nah, just trying to fix my build here, didn't look into that too much.
Your patch is of course welcome ;-)

> Thanks
> Guennadi
>
>>
>> Cc: Ian Molton <spyro at f2s.com>
>> Cc: Magnus Damm <damm at opensource.se>
>> Signed-off-by: Eric Miao <eric.y.miao at gmail.com>
>> ---
>>  drivers/mmc/host/tmio_mmc.c |    2 +-
>>  drivers/mmc/host/tmio_mmc.h |    5 ++---
>>  2 files changed, 3 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/mmc/host/tmio_mmc.c b/drivers/mmc/host/tmio_mmc.c
>> index ee7d0a5..24b9c3e 100644
>> --- a/drivers/mmc/host/tmio_mmc.c
>> +++ b/drivers/mmc/host/tmio_mmc.c
>> @@ -191,7 +191,7 @@ static void tmio_mmc_pio_irq(struct tmio_mmc_host *host)
>>
>>       host->sg_off += count;
>>
>> -     tmio_mmc_kunmap_atomic(host, &flags);
>> +     tmio_mmc_kunmap_atomic(buf, &flags);
>>
>>       if (host->sg_off == host->sg_ptr->length)
>>               tmio_mmc_next_sg(host);
>> diff --git a/drivers/mmc/host/tmio_mmc.h b/drivers/mmc/host/tmio_mmc.h
>> index 64f7d5d..8f308b9 100644
>> --- a/drivers/mmc/host/tmio_mmc.h
>> +++ b/drivers/mmc/host/tmio_mmc.h
>> @@ -186,10 +186,9 @@ static inline char *tmio_mmc_kmap_atomic(struct tmio_mmc_host *host,
>>       return kmap_atomic(sg_page(sg), KM_BIO_SRC_IRQ) + sg->offset;
>>  }
>>
>> -static inline void tmio_mmc_kunmap_atomic(struct tmio_mmc_host *host,
>> -     unsigned long *flags)
>> +static inline void tmio_mmc_kunmap_atomic(void *buf, unsigned long *flags)
>>  {
>> -     kunmap_atomic(sg_page(host->sg_ptr), KM_BIO_SRC_IRQ);
>> +     kunmap_atomic(buf, KM_BIO_SRC_IRQ);
>>       local_irq_restore(*flags);
>>  }
>>
>> --
>> 1.7.0.4
>>
>>
>> _______________________________________________
>> linux-arm-kernel mailing list
>> linux-arm-kernel at lists.infradead.org
>> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
>>
>
> ---
> Guennadi Liakhovetski, Ph.D.
> Freelance Open-Source Software Developer
> http://www.open-technology.de/
>