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From: Luis Henriques <lhenriques@suse.de>
To: David Howells <dhowells@redhat.com>
Cc: Jarkko Sakkinen <jarkko@kernel.org>,  Eric Biggers
 <ebiggers@kernel.org>,  keyrings@vger.kernel.org,
  linux-kernel@vger.kernel.org
Subject: Re: [PATCH v3] keys: update key quotas in key_put()
In-Reply-To: <3007646.1707134664@warthog.procyon.org.uk> (David Howells's
	message of "Mon, 05 Feb 2024 12:04:24 +0000")
References: <20240130101344.28936-1-lhenriques@suse.de>
	<3007646.1707134664@warthog.procyon.org.uk>
Date: Mon, 05 Feb 2024 13:54:11 +0000
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David Howells <dhowells@redhat.com> writes:

> Luis Henriques <lhenriques@suse.de> wrote:
>
>> Delaying key quotas update when key's refcount reaches 0 in key_put() has
>> been causing some issues in fscrypt testing, specifically in fstest
>> generic/581.  This commit fixes this test flakiness by dealing with the
>> quotas immediately, and leaving all the other clean-ups to the key garba=
ge
>> collector.
>
> Okay, I'll accept this.
>

That's awesome, thanks a lot David.  And, as Eric requested, I'll send out
shortly a follow-up fscrypt-specific patch, which will make generic/581
fstest finally pass.

Cheers,
--=20
Lu=C3=ADs


>> This is done by moving the updates to the qnkeys and qnbytes fields in
>> struct key_user from key_gc_unused_keys() into key_put().
>> Unfortunately, this also means that we need to switch to the
>> irq-version of the spinlock that protects these fields and use
>> spin_lock_{irqsave,irqrestore} in all the code that touches these
>> fields.
>
> ... Which shouldn't be that often.  It only happens when a key is created=
 or
> finally let go of.
>
>> Signed-off-by: Luis Henriques <lhenriques@suse.de>
>
> Acked-by: David Howells <dhowells@redhat.com>
>
> Jarkko - could you pick this up?
>