Re: [GIT PULL] MMC updates

[Pierre Ossman <drzeus-list@drzeus.cx>]

Nick Piggin wrote:
>> @@ -501,9 +501,9 @@ void mmc_detect_change(struct mmc_host *host,
>> unsigned long delay)
>>  {
>>  #ifdef CONFIG_MMC_DEBUG
>>      unsigned long flags;
>> -    spin_lock_irqsave(host->lock, flags);
>> +    spin_lock_irqsave(&host->lock, flags);
>>      BUG_ON(host->removed);
>> -    spin_unlock_irqrestore(host->lock, flags);
>> +    spin_unlock_irqrestore(&host->lock, flags);
>>  #endif
>
> Do you actually need the lock there at all? What is it protecting?
>

It makes sure we don't have any race when it comes to modifying
host->removed. We had some problems where controllers reported card
insertion events even after they'd signaled to be removed, causing all
kind of odd problems. This check was added to easier spot it should it
arise again.

Rgds

-- 
     -- Pierre Ossman

  Linux kernel, MMC maintainer        http://www.kernel.org
  PulseAudio, core developer          http://pulseaudio.org
  rdesktop, core developer          http://www.rdesktop.org