Re: [RFC][PATCH] VFS: create /proc//mountinfo

H. Peter Anvin
2008-01-23T19:17:45Z

Pavel Machek wrote:
> On Sun 2008-01-20 09:23:00, Miklos Szeredi wrote:
>>> Miklos Szeredi wrote:
>>>> - for mount ID's use IDA (from the IDR library) instead of a 32bit
>>>> counter, which could overflow
>>> IDAs tend to get reused quickly, which can cause race conditions. Any
>>> reason not to just use a 64-bit counter?
>> They tend to become hard to parse/compare for humans after a while.
>> And all this is basically only for humans, so race conditions don't
>> really matter. Also a changed mount with a reused ID is easily
>> identified by comparing the other fields.
>
> Hmm, smart humans only compare last few digits if they don't care
> about 100% reliability, and dumb software compares 64bits easily...
> Pavel

Indeed.

And this is most certainly NOT only for humans, and race conditions most
certainly matter.

-hpa