linux-kernel - [RFC 14/19] HSI: omap_ssi_port: avoid calling runtime_pm_*

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Sat, 18 Jun 2016 18:27:04 +0200
From:	Sebastian Reichel <sre@...nel.org>
To:	Sebastian Reichel <sre@...nel.org>, linux-omap@...r.kernel.org,
	linux-kernel@...r.kernel.org
Cc:	Tony Lindgren <tony@...mide.com>,
	Aaro Koskinen <aaro.koskinen@....fi>,
	Pavel Machek <pavel@....cz>,
	Ivaylo Dimitrov <ivo.g.dimitrov.75@...il.com>,
	Pali Rohár <pali.rohar@...il.com>
Subject: [RFC 14/19] HSI: omap_ssi_port: avoid calling runtime_pm_*_sync inside spinlock

runtime_pm_*_sync can block when irq_safe flag is removed
from omap-ssi driver, so it may not be called while a
spinlock is held.

Signed-off-by: Sebastian Reichel <sre@...nel.org>
---
 drivers/hsi/controllers/omap_ssi_port.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/hsi/controllers/omap_ssi_port.c b/drivers/hsi/controllers/omap_ssi_port.c
index f7ed59ba3b2c..92064221dbab 100644
--- a/drivers/hsi/controllers/omap_ssi_port.c
+++ b/drivers/hsi/controllers/omap_ssi_port.c
@@ -767,13 +767,12 @@ static int ssi_release(struct hsi_client *cl)
 	struct omap_ssi_port *omap_port = hsi_port_drvdata(port);
 	struct hsi_controller *ssi = to_hsi_controller(port->device.parent);
 
-	spin_lock_bh(&omap_port->lock);
 	pm_runtime_get_sync(omap_port->pdev);
+	spin_lock_bh(&omap_port->lock);
 	/* Stop all the pending DMA requests for that client */
 	ssi_cleanup_gdd(ssi, cl);
 	/* Now cleanup all the queues */
 	ssi_cleanup_queues(cl);
-	pm_runtime_put_sync(omap_port->pdev);
 	/* If it is the last client of the port, do extra checks and cleanup */
 	if (port->claimed <= 1) {
 		/*
@@ -782,15 +781,16 @@ static int ssi_release(struct hsi_client *cl)
 		 */
 		if (test_and_clear_bit(SSI_WAKE_EN, &omap_port->flags))
 			pm_runtime_put_sync(omap_port->pdev);
-		pm_runtime_get_sync(omap_port->pdev);
+		pm_runtime_get(omap_port->pdev);
 		/* Stop any SSI TX/RX without a client */
 		ssi_set_port_mode(omap_port, SSI_MODE_SLEEP);
 		omap_port->sst.mode = SSI_MODE_SLEEP;
 		omap_port->ssr.mode = SSI_MODE_SLEEP;
-		pm_runtime_put_sync(omap_port->pdev);
+		pm_runtime_put(omap_port->pdev);
 		WARN_ON(omap_port->wk_refcount != 0);
 	}
 	spin_unlock_bh(&omap_port->lock);
+	pm_runtime_put_sync(omap_port->pdev);
 
 	return 0;
 }
-- 
2.8.1