2022-12-28 16:25:49

by Manivannan Sadhasivam

Subject: [PATCH 6/6] bus: mhi: ep: Save channel state locally during suspend and resume

During suspend and resume, the channel state needs to be saved locally.
Otherwise, the endpoint may access the channels while they were being
suspended and causing access violations.

Fix it by saving the channel state locally during suspend and resume.

Cc: <[email protected]> # 5.19
Fixes: e4b7b5f0f30a ("bus: mhi: ep: Add support for suspending and resuming channels")
Signed-off-by: Manivannan Sadhasivam <[email protected]>
---
drivers/bus/mhi/ep/main.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/drivers/bus/mhi/ep/main.c b/drivers/bus/mhi/ep/main.c
index 2362fcc8b32c..bcaaba97ef63 100644
--- a/drivers/bus/mhi/ep/main.c
+++ b/drivers/bus/mhi/ep/main.c
@@ -1122,6 +1122,7 @@ void mhi_ep_suspend_channels(struct mhi_ep_cntrl *mhi_cntrl)

dev_dbg(&mhi_chan->mhi_dev->dev, "Suspending channel\n");
/* Set channel state to SUSPENDED */
+ mhi_chan->state = MHI_CH_STATE_SUSPENDED;
tmp &= ~CHAN_CTX_CHSTATE_MASK;
tmp |= FIELD_PREP(CHAN_CTX_CHSTATE_MASK, MHI_CH_STATE_SUSPENDED);
mhi_cntrl->ch_ctx_cache[i].chcfg = cpu_to_le32(tmp);
@@ -1151,6 +1152,7 @@ void mhi_ep_resume_channels(struct mhi_ep_cntrl *mhi_cntrl)

dev_dbg(&mhi_chan->mhi_dev->dev, "Resuming channel\n");
/* Set channel state to RUNNING */
+ mhi_chan->state = MHI_CH_STATE_RUNNING;
tmp &= ~CHAN_CTX_CHSTATE_MASK;
tmp |= FIELD_PREP(CHAN_CTX_CHSTATE_MASK, MHI_CH_STATE_RUNNING);
mhi_cntrl->ch_ctx_cache[i].chcfg = cpu_to_le32(tmp);
--
2.25.1

2023-01-05 16:28:04

by Jeffrey Hugo

Subject: Re: [PATCH 6/6] bus: mhi: ep: Save channel state locally during suspend and resume

On 12/28/2022 9:17 AM, Manivannan Sadhasivam wrote:
> During suspend and resume, the channel state needs to be saved locally.
> Otherwise, the endpoint may access the channels while they were being
> suspended and causing access violations.
>
> Fix it by saving the channel state locally during suspend and resume.
>
> Cc: <[email protected]> # 5.19
> Fixes: e4b7b5f0f30a ("bus: mhi: ep: Add support for suspending and resuming channels")
> Signed-off-by: Manivannan Sadhasivam <[email protected]>

Reviewed-by: Jeffrey Hugo <[email protected])