linux-kernel - [PATCH v6 3/5] mei: gsc: setup char driver alive in spite of firmware handshake failure

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]

Message-Id: <20220213091458.2364014-4-alexander.usyskin@intel.com>
Date:   Sun, 13 Feb 2022 11:14:56 +0200
From:   Alexander Usyskin <alexander.usyskin@...el.com>
To:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        Jani Nikula <jani.nikula@...ux.intel.com>,
        Joonas Lahtinen <joonas.lahtinen@...ux.intel.com>,
        Rodrigo Vivi <rodrigo.vivi@...el.com>,
        David Airlie <airlied@...ux.ie>,
        Daniel Vetter <daniel@...ll.ch>
Cc:     Tomas Winkler <tomas.winkler@...el.com>,
        Alexander Usyskin <alexander.usyskin@...el.com>,
        Vitaly Lubart <vitaly.lubart@...el.com>,
        intel-gfx@...ts.freedesktop.org, linux-kernel@...r.kernel.org
Subject: [PATCH v6 3/5] mei: gsc: setup char driver alive in spite of firmware handshake failure

Setup char device in spite of firmware handshake failure.
In order to provide host access to the firmware status registers and other
information required for the manufacturing process.

Signed-off-by: Alexander Usyskin <alexander.usyskin@...el.com>
Signed-off-by: Tomas Winkler <tomas.winkler@...el.com>
---
V5: Rebase
V6: Rebase
---
 drivers/misc/mei/gsc-me.c | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/drivers/misc/mei/gsc-me.c b/drivers/misc/mei/gsc-me.c
index 0afae70e0609..cf427f6fdec9 100644
--- a/drivers/misc/mei/gsc-me.c
+++ b/drivers/misc/mei/gsc-me.c
@@ -79,11 +79,12 @@ static int mei_gsc_probe(struct auxiliary_device *aux_dev,
 	pm_runtime_set_active(device);
 	pm_runtime_enable(device);
 
-	if (mei_start(dev)) {
-		dev_err(device, "init hw failure.\n");
-		ret = -ENODEV;
-		goto err;
-	}
+	/* Continue to char device setup in spite of firmware handshake failure.
+	 * In order to provide access to the firmware status registers to the user
+	 * space via sysfs.
+	 */
+	if (mei_start(dev))
+		dev_warn(device, "init hw failure.\n");
 
 	pm_runtime_set_autosuspend_delay(device, MEI_GSC_RPM_TIMEOUT);
 	pm_runtime_use_autosuspend(device);
-- 
2.32.0