| Message ID | 20230706211414.10660-1-dg573847474@gmail.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [RESEND] i2c: bcm-iproc: Fix bcm_iproc_i2c_isr deadlock issue | expand |
Hi Ray and Wolfram,
> I can't apply it, what version is this against?
The patch is based on 6.4-rc7. I resend the patch with this
email because I had some problems setting up the previous
one with git send-email. That patch was manually pasted
so that might be the reason for not being able to be applied.
Best Regards,
Chengfeng
Some comments inline On 2023-07-06 14:14, Chengfeng Ye wrote: > 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. > Add Fixes: tag here. > Signed-off-by: Chengfeng Ye <dg573847474@gmail.com> > --- > drivers/i2c/busses/i2c-bcm-iproc.c | 10 ++++++---- > 1 file changed, 6 insertions(+), 4 deletions(-) > > diff --git a/drivers/i2c/busses/i2c-bcm-iproc.c b/drivers/i2c/busses/i2c-bcm-iproc.c > index 85d8a6b04885..d02245e4db8c 100644 > --- a/drivers/i2c/busses/i2c-bcm-iproc.c > +++ b/drivers/i2c/busses/i2c-bcm-iproc.c > @@ -233,13 +233,14 @@ static inline u32 iproc_i2c_rd_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); > 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); > } > @@ -250,12 +251,13 @@ static inline u32 iproc_i2c_rd_reg(struct bcm_iproc_i2c_dev *iproc_i2c, > static inline void iproc_i2c_wr_reg(struct bcm_iproc_i2c_dev *iproc_i2c, > u32 offset, u32 val) > { > + unsigned long flags; Add newline after variable declarations. > 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); > }
On 7/6/2023 2:21 PM, Chengfeng Ye wrote: > Hi Ray and Wolfram, > >> I can't apply it, what version is this against? > > The patch is based on 6.4-rc7. I resend the patch with this > email because I had some problems setting up the previous > one with git send-email. That patch was manually pasted > so that might be the reason for not being able to be applied. > > Best Regards, > Chengfeng I saw your latest patch. You should use prefix of [PATCH V2] instead of [PATCH RESEND]. Also, can you please add the fix tag I identified to your commit message. That will save Wolfram some manual work. Thanks, Ray
> Also, can you please add the fix tag I identified to your commit > message. That will save Wolfram some > manual work. > Add newline after variable declarations. Thanks for the reply. Fixed these problems in v2 patch. Best Regards, Chengfeng
diff --git a/drivers/i2c/busses/i2c-bcm-iproc.c b/drivers/i2c/busses/i2c-bcm-iproc.c index 85d8a6b04885..d02245e4db8c 100644 --- a/drivers/i2c/busses/i2c-bcm-iproc.c +++ b/drivers/i2c/busses/i2c-bcm-iproc.c @@ -233,13 +233,14 @@ static inline u32 iproc_i2c_rd_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); 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); } @@ -250,12 +251,13 @@ static inline u32 iproc_i2c_rd_reg(struct bcm_iproc_i2c_dev *iproc_i2c, 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); }
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. Signed-off-by: Chengfeng Ye <dg573847474@gmail.com> --- drivers/i2c/busses/i2c-bcm-iproc.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-)