This is a note to let you know that I've just added the patch titled
can: tcan4x5x: tcan4x5x_init(): fix initialization - clear MRAM before entering Normal Mode
to the 5.11-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
can-tcan4x5x-tcan4x5x_init-fix-initialization-clear-mram-before-entering-normal-mode.patch
and it can be found in the queue-5.11 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 2712625200ed69c642b9abc3a403830c4643364c Mon Sep 17 00:00:00 2001
From: Torin Cooper-Bennun <torin@xxxxxxxxxxxxxxxxxx>
Date: Fri, 26 Feb 2021 16:34:41 +0000
Subject: can: tcan4x5x: tcan4x5x_init(): fix initialization - clear MRAM before entering Normal Mode
From: Torin Cooper-Bennun <torin@xxxxxxxxxxxxxxxxxx>
commit 2712625200ed69c642b9abc3a403830c4643364c upstream.
This patch prevents a potentially destructive race condition. The
device is fully operational on the bus after entering Normal Mode, so
zeroing the MRAM after entering this mode may lead to loss of
information, e.g. new received messages.
This patch fixes the problem by first initializing the MRAM, then
bringing the device into Normale Mode.
Fixes: 5443c226ba91 ("can: tcan4x5x: Add tcan4x5x driver to the kernel")
Link: https://lore.kernel.org/r/20210226163440.313628-1-torin@xxxxxxxxxxxxxxxxxx
Suggested-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx>
Signed-off-by: Torin Cooper-Bennun <torin@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/can/m_can/tcan4x5x.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
--- a/drivers/net/can/m_can/tcan4x5x.c
+++ b/drivers/net/can/m_can/tcan4x5x.c
@@ -326,14 +326,14 @@ static int tcan4x5x_init(struct m_can_cl
if (ret)
return ret;
+ /* Zero out the MCAN buffers */
+ m_can_init_ram(cdev);
+
ret = regmap_update_bits(tcan4x5x->regmap, TCAN4X5X_CONFIG,
TCAN4X5X_MODE_SEL_MASK, TCAN4X5X_MODE_NORMAL);
if (ret)
return ret;
- /* Zero out the MCAN buffers */
- m_can_init_ram(cdev);
-
return ret;
}
Patches currently in stable-queue which might be from torin@xxxxxxxxxxxxxxxxxx are
queue-5.11/can-tcan4x5x-tcan4x5x_init-fix-initialization-clear-mram-before-entering-normal-mode.patch
