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* [PATCH AUTOSEL 4.19 024/101] tty: serial: msm_serial: avoid system lockup condition
       [not found] <20190719040732.17285-1-sashal@kernel.org>
@ 2019-07-19  4:06 ` Sasha Levin
  2019-07-19  4:06 ` [PATCH AUTOSEL 4.19 039/101] drm/msm: Depopulate platform on probe failure Sasha Levin
  1 sibling, 0 replies; 2+ messages in thread
From: Sasha Levin @ 2019-07-19  4:06 UTC (permalink / raw)
  To: linux-kernel, stable
  Cc: Jorge Ramirez-Ortiz, Greg Kroah-Hartman, Sasha Levin,
	linux-arm-msm, linux-serial

From: Jorge Ramirez-Ortiz <jorge.ramirez-ortiz@linaro.org>

[ Upstream commit ba3684f99f1b25d2a30b6956d02d339d7acb9799 ]

The function msm_wait_for_xmitr can be taken with interrupts
disabled. In order to avoid a potential system lockup - demonstrated
under stress testing conditions on SoC QCS404/5 - make sure we wait
for a bounded amount of time.

Tested on SoC QCS404.

Signed-off-by: Jorge Ramirez-Ortiz <jorge.ramirez-ortiz@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/tty/serial/msm_serial.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/tty/serial/msm_serial.c b/drivers/tty/serial/msm_serial.c
index 0f41b936da03..310bbae515b0 100644
--- a/drivers/tty/serial/msm_serial.c
+++ b/drivers/tty/serial/msm_serial.c
@@ -383,10 +383,14 @@ static void msm_request_rx_dma(struct msm_port *msm_port, resource_size_t base)
 
 static inline void msm_wait_for_xmitr(struct uart_port *port)
 {
+	unsigned int timeout = 500000;
+
 	while (!(msm_read(port, UART_SR) & UART_SR_TX_EMPTY)) {
 		if (msm_read(port, UART_ISR) & UART_ISR_TX_READY)
 			break;
 		udelay(1);
+		if (!timeout--)
+			break;
 	}
 	msm_write(port, UART_CR_CMD_RESET_TX_READY, UART_CR);
 }
-- 
2.20.1


^ permalink raw reply	[flat|nested] 2+ messages in thread

* [PATCH AUTOSEL 4.19 039/101] drm/msm: Depopulate platform on probe failure
       [not found] <20190719040732.17285-1-sashal@kernel.org>
  2019-07-19  4:06 ` [PATCH AUTOSEL 4.19 024/101] tty: serial: msm_serial: avoid system lockup condition Sasha Levin
@ 2019-07-19  4:06 ` Sasha Levin
  1 sibling, 0 replies; 2+ messages in thread
From: Sasha Levin @ 2019-07-19  4:06 UTC (permalink / raw)
  To: linux-kernel, stable
  Cc: Sean Paul, Rob Clark, Sasha Levin, linux-arm-msm, dri-devel, freedreno

From: Sean Paul <seanpaul@chromium.org>

[ Upstream commit 4368a1539c6b41ac3cddc06f5a5117952998804c ]

add_display_components() calls of_platform_populate, and we depopluate
on pdev remove, but not when probe fails. So if we get a probe deferral
in one of the components, we won't depopulate the platform. This causes
the core to keep references to devices which should be destroyed, which
causes issues when those same devices try to re-initialize on the next
probe attempt.

I think this is the reason we had issues with the gmu's device-managed
resources on deferral (worked around in commit 94e3a17f33a5).

Reviewed-by: Rob Clark <robdclark@chromium.org>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190617201301.133275-3-sean@poorly.run
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/gpu/drm/msm/msm_drv.c | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/msm/msm_drv.c b/drivers/gpu/drm/msm/msm_drv.c
index c1abad8a8612..ed9a3a1e50ef 100644
--- a/drivers/gpu/drm/msm/msm_drv.c
+++ b/drivers/gpu/drm/msm/msm_drv.c
@@ -1321,16 +1321,24 @@ static int msm_pdev_probe(struct platform_device *pdev)
 
 	ret = add_gpu_components(&pdev->dev, &match);
 	if (ret)
-		return ret;
+		goto fail;
 
 	/* on all devices that I am aware of, iommu's which can map
 	 * any address the cpu can see are used:
 	 */
 	ret = dma_set_mask_and_coherent(&pdev->dev, ~0);
 	if (ret)
-		return ret;
+		goto fail;
+
+	ret = component_master_add_with_match(&pdev->dev, &msm_drm_ops, match);
+	if (ret)
+		goto fail;
 
-	return component_master_add_with_match(&pdev->dev, &msm_drm_ops, match);
+	return 0;
+
+fail:
+	of_platform_depopulate(&pdev->dev);
+	return ret;
 }
 
 static int msm_pdev_remove(struct platform_device *pdev)
-- 
2.20.1


^ permalink raw reply	[flat|nested] 2+ messages in thread

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2019-07-19  4:06 ` [PATCH AUTOSEL 4.19 024/101] tty: serial: msm_serial: avoid system lockup condition Sasha Levin
2019-07-19  4:06 ` [PATCH AUTOSEL 4.19 039/101] drm/msm: Depopulate platform on probe failure Sasha Levin

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