This is a note to let you know that I've just added the patch titled
i2c: bcm-iproc: Fix bcm_iproc_i2c_isr deadlock issue
to the 5.4-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:
i2c-bcm-iproc-fix-bcm_iproc_i2c_isr-deadlock-issue.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 4caf4cb1eaed469742ef719f2cc024b1ec3fa9e6 Mon Sep 17 00:00:00 2001
From: Chengfeng Ye <dg573847474@xxxxxxxxx>
Date: Fri, 7 Jul 2023 08:49:41 +0000
Subject: i2c: bcm-iproc: Fix bcm_iproc_i2c_isr deadlock issue
From: Chengfeng Ye <dg573847474@xxxxxxxxx>
commit 4caf4cb1eaed469742ef719f2cc024b1ec3fa9e6 upstream.
iproc_i2c_rd_reg() and iproc_i2c_wr_reg() are called from both
interrupt context (e.g. bcm_iproc_i2c_isr) and process context
(e.g. bcm_iproc_i2c_suspend). Therefore, interrupts should be
disabled to avoid potential deadlock. To prevent this scenario,
use spin_lock_irqsave().
Fixes: 9a1038728037 ("i2c: iproc: add NIC I2C support")
Signed-off-by: Chengfeng Ye <dg573847474@xxxxxxxxx>
Acked-by: Ray Jui <ray.jui@xxxxxxxxxxxx>
Reviewed-by: Andi Shyti <andi.shyti@xxxxxxxxxx>
Signed-off-by: Wolfram Sang <wsa@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/i2c/busses/i2c-bcm-iproc.c | 11 +++++++----
1 file changed, 7 insertions(+), 4 deletions(-)
--- a/drivers/i2c/busses/i2c-bcm-iproc.c
+++ b/drivers/i2c/busses/i2c-bcm-iproc.c
@@ -240,13 +240,14 @@ static inline u32 iproc_i2c_rd_reg(struc
u32 offset)
{
u32 val;
+ unsigned long flags;
if (iproc_i2c->idm_base) {
- spin_lock(&iproc_i2c->idm_lock);
+ spin_lock_irqsave(&iproc_i2c->idm_lock, flags);
writel(iproc_i2c->ape_addr_mask,
iproc_i2c->idm_base + IDM_CTRL_DIRECT_OFFSET);
val = readl(iproc_i2c->base + offset);
- spin_unlock(&iproc_i2c->idm_lock);
+ spin_unlock_irqrestore(&iproc_i2c->idm_lock, flags);
} else {
val = readl(iproc_i2c->base + offset);
}
@@ -257,12 +258,14 @@ static inline u32 iproc_i2c_rd_reg(struc
static inline void iproc_i2c_wr_reg(struct bcm_iproc_i2c_dev *iproc_i2c,
u32 offset, u32 val)
{
+ unsigned long flags;
+
if (iproc_i2c->idm_base) {
- spin_lock(&iproc_i2c->idm_lock);
+ spin_lock_irqsave(&iproc_i2c->idm_lock, flags);
writel(iproc_i2c->ape_addr_mask,
iproc_i2c->idm_base + IDM_CTRL_DIRECT_OFFSET);
writel(val, iproc_i2c->base + offset);
- spin_unlock(&iproc_i2c->idm_lock);
+ spin_unlock_irqrestore(&iproc_i2c->idm_lock, flags);
} else {
writel(val, iproc_i2c->base + offset);
}
Patches currently in stable-queue which might be from dg573847474@xxxxxxxxx are
queue-5.4/i2c-bcm-iproc-fix-bcm_iproc_i2c_isr-deadlock-issue.patch
