From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 53DDD33CE for ; Mon, 30 Jan 2023 14:20:30 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id AC020C433D2; Mon, 30 Jan 2023 14:20:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1675088430; bh=gHlPMaOgS6FPp3ojpd/qqAIvyC0uF+49MU2zbAkwKYU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=hQcczWi+zJfSbhrRS7jaFpIPO2ekTbwrcj87S2yNp33lbK6+QjRnH7lvSwJzACb9Y l0/M9LWqxx/spyqP/53p6K4g6u72p0TC/cin62zIhlWnu9SqYM5vLtFjZ4jsXeda9I 2UW8PiyUd6NqKjK56zj8e3YAaJEpBjy0B1aDeWkE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Dean Luick , Dennis Dalessandro , Leon Romanovsky , Sasha Levin Subject: [PATCH 5.10 017/143] IB/hfi1: Reserve user expected TIDs Date: Mon, 30 Jan 2023 14:51:14 +0100 Message-Id: <20230130134307.598775923@linuxfoundation.org> X-Mailer: git-send-email 2.39.1 In-Reply-To: <20230130134306.862721518@linuxfoundation.org> References: <20230130134306.862721518@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Dean Luick [ Upstream commit ecf91551cdd2925ed6d9a9d99074fa5f67b90596 ] To avoid a race, reserve the number of user expected TIDs before setup. Fixes: 7e7a436ecb6e ("staging/hfi1: Add TID entry program function body") Signed-off-by: Dean Luick Signed-off-by: Dennis Dalessandro Link: https://lore.kernel.org/r/167328547636.1472310.7419712824785353905.stgit@awfm-02.cornelisnetworks.com Signed-off-by: Leon Romanovsky Signed-off-by: Sasha Levin --- drivers/infiniband/hw/hfi1/user_exp_rcv.c | 14 ++++++-------- 1 file changed, 6 insertions(+), 8 deletions(-) diff --git a/drivers/infiniband/hw/hfi1/user_exp_rcv.c b/drivers/infiniband/hw/hfi1/user_exp_rcv.c index dd8ce2a62d2b..1278cd55a480 100644 --- a/drivers/infiniband/hw/hfi1/user_exp_rcv.c +++ b/drivers/infiniband/hw/hfi1/user_exp_rcv.c @@ -324,16 +324,13 @@ int hfi1_user_exp_rcv_setup(struct hfi1_filedata *fd, /* Find sets of physically contiguous pages */ tidbuf->n_psets = find_phys_blocks(tidbuf, pinned); - /* - * We don't need to access this under a lock since tid_used is per - * process and the same process cannot be in hfi1_user_exp_rcv_clear() - * and hfi1_user_exp_rcv_setup() at the same time. - */ + /* Reserve the number of expected tids to be used. */ spin_lock(&fd->tid_lock); if (fd->tid_used + tidbuf->n_psets > fd->tid_limit) pageset_count = fd->tid_limit - fd->tid_used; else pageset_count = tidbuf->n_psets; + fd->tid_used += pageset_count; spin_unlock(&fd->tid_lock); if (!pageset_count) @@ -442,10 +439,11 @@ int hfi1_user_exp_rcv_setup(struct hfi1_filedata *fd, nomem: hfi1_cdbg(TID, "total mapped: tidpairs:%u pages:%u (%d)", tididx, mapped_pages, ret); + /* adjust reserved tid_used to actual count */ + spin_lock(&fd->tid_lock); + fd->tid_used -= pageset_count - tididx; + spin_unlock(&fd->tid_lock); if (tididx) { - spin_lock(&fd->tid_lock); - fd->tid_used += tididx; - spin_unlock(&fd->tid_lock); tinfo->tidcnt = tididx; tinfo->length = mapped_pages * PAGE_SIZE; -- 2.39.0