From: David Howells <dhowells@redhat.com>
To: Oleg Nesterov <oleg@redhat.com>
Cc: dhowells@redhat.com, Alexey Gladkov <legion@kernel.org>,
Andrew Morton <akpm@linux-foundation.org>,
Mateusz Guzik <mjguzik@gmail.com>,
"Paul E. McKenney" <paulmck@kernel.org>,
linux-kernel@vger.kernel.org
Subject: Re: [RFC 2/1] kill task_ucounts()->rcu_read_lock(), add __task_ucounts()
Date: Mon, 27 Oct 2025 14:55:56 +0000 [thread overview]
Message-ID: <2258932.1761576956@warthog.procyon.org.uk> (raw)
In-Reply-To: <20251026143501.GA22472@redhat.com>
Oleg Nesterov <oleg@redhat.com> wrote:
> So I think task_ucounts() can just do
>
> /* The caller must ensure that ->real_cred is stable or take rcu_read_lock() */
> #define task_ucounts(task) \
> rcu_dereference_check((task)->real_cred, 1)->ucounts
Can you use rcu_access_pointer() within exit.c? E.g.:
struct cred *pcreds = rcu_access_pointer(task->real_cred);
dec_rlimit_ucounts(pcreds->ucounts, UCOUNT_RLIMIT_NPROC, 1);
David
next prev parent reply other threads:[~2025-10-27 14:56 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-10-26 14:31 [PATCH 1/1] release_task: kill unnecessary rcu_read_lock() around dec_rlimit_ucounts() Oleg Nesterov
2025-10-26 14:35 ` [RFC 2/1] kill task_ucounts()->rcu_read_lock(), add __task_ucounts() Oleg Nesterov
2025-10-26 14:49 ` Mateusz Guzik
2025-10-27 14:55 ` David Howells [this message]
2025-10-27 15:18 ` Paul E. McKenney
2025-10-26 15:44 ` [PATCH 1/1] release_task: kill unnecessary rcu_read_lock() around dec_rlimit_ucounts() Alexey Gladkov
2025-10-27 14:51 ` David Howells
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