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From:   David Howells <dhowells@redhat.com>
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To:     Hawkins Jiawei <yin31149@gmail.com>
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Subject: Re: [PATCH] rxrpc: fix bad unlock balance in rxrpc_do_sendmsg
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Content-ID: <924817.1661158094.1@warthog.procyon.org.uk>
Date:   Mon, 22 Aug 2022 09:48:14 +0100
Message-ID: <924818.1661158094@warthog.procyon.org.uk>
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Hawkins Jiawei <yin31149@gmail.com> wrote:

> -		if (mutex_lock_interruptible(&call->user_mutex) < 0)
> +		if (mutex_lock_interruptible(&call->user_mutex) < 0) {
> +			mutex_lock(&call->user_mutex);

Yeah, as Khalid points out that kind of makes the interruptible lock
pointless.  Either rxrpc_send_data() needs to return a separate indication
that we returned without the lock held or it needs to always drop the lock on
error (at least for ERESTARTSYS/EINTR) which can be checked for higher up.

David