Re: [RFC][PATCH] VFS: create /proc/<pid>/mountinfo

From: H. Peter Anvin
Date: Wed Jan 23 2008 - 14:17:48 EST


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
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