[PATCH AUTOSEL 5.3 063/203] firmware: arm_scmi: Check if platform has released shmem before using

[PATCH AUTOSEL 5.3 063/203] firmware: arm_scmi: Check if platform has released shmem before using

[Sasha Levin]

From: Sudeep Holla <sudeep.holla@arm.com>

[ Upstream commit 9dc34d635c67e57051853855c43249408641a5ab ]

Sometimes platfom may take too long to respond to the command and OS
might timeout before platform transfer the ownership of the shared
memory region to the OS with the response.

Since the mailbox channel associated with the channel is freed and new
commands are dispatch on the same channel, OS needs to wait until it
gets back the ownership. If not, either OS may end up overwriting the
platform response for the last command(which is fine as OS timed out
that command) or platform might overwrite the payload for the next
command with the response for the old.

The latter is problematic as platform may end up interpretting the
response as the payload. In order to avoid such race, let's wait until
the OS gets back the ownership before we prepare the shared memory with
the payload for the next command.

Reported-by: Jim Quinlan <james.quinlan@broadcom.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/firmware/arm_scmi/driver.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c
index b5bc4c7a8fab2..b49c9e6f4bf10 100644
--- a/drivers/firmware/arm_scmi/driver.c
+++ b/drivers/firmware/arm_scmi/driver.c
@@ -271,6 +271,14 @@ static void scmi_tx_prepare(struct mbox_client *cl, void *m)
 	struct scmi_chan_info *cinfo = client_to_scmi_chan_info(cl);
 	struct scmi_shared_mem __iomem *mem = cinfo->payload;
 
+	/*
+	 * Ideally channel must be free by now unless OS timeout last
+	 * request and platform continued to process the same, wait
+	 * until it releases the shared memory, otherwise we may endup
+	 * overwriting its response with new message payload or vice-versa
+	 */
+	spin_until_cond(ioread32(&mem->channel_status) &
+			SCMI_SHMEM_CHAN_STAT_CHANNEL_FREE);
 	/* Mark channel busy + clear error */
 	iowrite32(0x0, &mem->channel_status);
 	iowrite32(t->hdr.poll_completion ? 0 : SCMI_SHMEM_FLAG_INTR_ENABLED,
-- 
2.20.1


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

[PATCH AUTOSEL 5.3 079/203] perf ftrace: Use CAP_SYS_ADMIN instead of euid==0

[Sasha Levin]

From: Igor Lubashev <ilubashe@akamai.com>

[ Upstream commit c766f3df635de14295e410c6dd5410bc416c24a0 ]

The kernel requires CAP_SYS_ADMIN instead of euid==0 to mount debugfs
for ftrace.  Make perf do the same.

Signed-off-by: Igor Lubashev <ilubashe@akamai.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: James Morris <jmorris@namei.org>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/bd8763b72ed4d58d0b42d44fbc7eb474d32e53a3.1565188228.git.ilubashe@akamai.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 tools/perf/builtin-ftrace.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/tools/perf/builtin-ftrace.c b/tools/perf/builtin-ftrace.c
index 0193128104056..10971255fd2dc 100644
--- a/tools/perf/builtin-ftrace.c
+++ b/tools/perf/builtin-ftrace.c
@@ -13,6 +13,7 @@
 #include <signal.h>
 #include <fcntl.h>
 #include <poll.h>
+#include <linux/capability.h>
 
 #include "debug.h"
 #include <subcmd/parse-options.h>
@@ -21,6 +22,7 @@
 #include "target.h"
 #include "cpumap.h"
 #include "thread_map.h"
+#include "util/cap.h"
 #include "util/config.h"
 
 
@@ -281,7 +283,7 @@ static int __cmd_ftrace(struct perf_ftrace *ftrace, int argc, const char **argv)
 		.events = POLLIN,
 	};
 
-	if (geteuid() != 0) {
+	if (!perf_cap__capable(CAP_SYS_ADMIN)) {
 		pr_err("ftrace only works for root!\n");
 		return -1;
 	}
-- 
2.20.1


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

[PATCH AUTOSEL 5.3 090/203] ARM: dts: imx7d: cl-som-imx7: make ethernet work again

[Sasha Levin]

From: André Draszik <git@andred.net>

[ Upstream commit 9846a4524ac90b63496580b7ad50674b40d92a8f ]

Recent changes to the atheros at803x driver caused
ethernet to stop working on this board.
In particular commit 6d4cd041f0af
("net: phy: at803x: disable delay only for RGMII mode")
and commit cd28d1d6e52e
("net: phy: at803x: Disable phy delay for RGMII mode")
fix the AR8031 driver to configure the phy's (RX/TX)
delays as per the 'phy-mode' in the device tree.

This now prevents ethernet from working on this board.

It used to work before those commits, because the
AR8031 comes out of reset with RX delay enabled, and
the at803x driver didn't touch the delay configuration
at all when "rgmii" mode was selected, and because
arch/arm/mach-imx/mach-imx7d.c:ar8031_phy_fixup()
unconditionally enables TX delay.

Since above commits ar8031_phy_fixup() also has no
effect anymore, and the end-result is that all delays
are disabled in the phy, no ethernet.

Update the device tree to restore functionality.

Signed-off-by: André Draszik <git@andred.net>
CC: Ilya Ledvich <ilya@compulab.co.il>
CC: Igor Grinberg <grinberg@compulab.co.il>
CC: Rob Herring <robh+dt@kernel.org>
CC: Mark Rutland <mark.rutland@arm.com>
CC: Shawn Guo <shawnguo@kernel.org>
CC: Sascha Hauer <s.hauer@pengutronix.de>
CC: Pengutronix Kernel Team <kernel@pengutronix.de>
CC: Fabio Estevam <festevam@gmail.com>
CC: NXP Linux Team <linux-imx@nxp.com>
CC: devicetree@vger.kernel.org
CC: linux-arm-kernel@lists.infradead.org
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/arm/boot/dts/imx7d-cl-som-imx7.dts | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arm/boot/dts/imx7d-cl-som-imx7.dts b/arch/arm/boot/dts/imx7d-cl-som-imx7.dts
index e61567437d73c..62d5e9a4a7818 100644
--- a/arch/arm/boot/dts/imx7d-cl-som-imx7.dts
+++ b/arch/arm/boot/dts/imx7d-cl-som-imx7.dts
@@ -44,7 +44,7 @@
 			  <&clks IMX7D_ENET1_TIME_ROOT_CLK>;
 	assigned-clock-parents = <&clks IMX7D_PLL_ENET_MAIN_100M_CLK>;
 	assigned-clock-rates = <0>, <100000000>;
-	phy-mode = "rgmii";
+	phy-mode = "rgmii-id";
 	phy-handle = <&ethphy0>;
 	fsl,magic-packet;
 	status = "okay";
@@ -70,7 +70,7 @@
 			  <&clks IMX7D_ENET2_TIME_ROOT_CLK>;
 	assigned-clock-parents = <&clks IMX7D_PLL_ENET_MAIN_100M_CLK>;
 	assigned-clock-rates = <0>, <100000000>;
-	phy-mode = "rgmii";
+	phy-mode = "rgmii-id";
 	phy-handle = <&ethphy1>;
 	fsl,magic-packet;
 	status = "okay";
-- 
2.20.1


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel