Re: [PATCH v8 07/11] proc: flush task dcache entries from all procfs instances
From: Linus Torvalds <torvalds@linux-foundation.org>
Date: 2020-02-12 21:08:47
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Possibly related (same subject, not in this thread)
- 2020-02-14 · Re: [PATCH v8 07/11] proc: flush task dcache entries from all procfs instances · Eric W. Biederman <hidden>
- 2020-02-14 · Re: [PATCH v8 07/11] proc: flush task dcache entries from all procfs instances · Eric W. Biederman <hidden>
- 2020-02-14 · Re: [PATCH v8 07/11] proc: flush task dcache entries from all procfs instances · Eric W. Biederman <hidden>
- 2020-02-13 · Re: [PATCH v8 07/11] proc: flush task dcache entries from all procfs instances · Linus Torvalds <torvalds@linux-foundation.org>
- 2020-02-13 · Re: [PATCH v8 07/11] proc: flush task dcache entries from all procfs instances · Al Viro <viro@zeniv.linux.org.uk>
On Wed, Feb 12, 2020 at 12:41 PM Al Viro [off-list ref] wrote:
On Wed, Feb 12, 2020 at 08:38:33PM +0000, Al Viro wrote:quoted
Wait, I thought the whole point of that had been to allow multiple procfs instances for the same userns? Confused...s/userns/pidns/, sorry
Right, but we still hold the ref to it here...
[ Looks more ]
Oooh. No we don't. Exactly because we don't hold the lock, only the
rcu lifetime, the ref can go away from under us. I see what your
concern is.
Ouch, this is more painful than I expected - the code flow looked so
simple. I really wanted to avoid a new lock during process shutdown,
because that has always been somewhat painful.
Linus