2022-11-30 13:10:21

by Ricardo Ribalda

[permalink] [raw]
Subject: [PATCH v3] mailbox: mtk-cmdq: Do not request irq until we are ready

If the system comes from kexec() the peripheral might trigger an IRQ
befoe we are ready for it. Triggering a crash due to an access to
invalid memory.

Signed-off-by: Ricardo Ribalda <[email protected]>
---
To: AngeloGioacchino Del Regno <[email protected]>
To: Jassi Brar <[email protected]>
To: Matthias Brugger <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
---
Changes in v3:
- Rebase on top of https://patchwork.kernel.org/project/linux-mediatek/patch/[email protected]/
- Link to v2: https://lore.kernel.org/r/[email protected]

Changes in v2:
- I have managed to repro a different panic. Moving the irq enabling to the very end of probe.
- Link to v1: https://lore.kernel.org/r/[email protected]
---
drivers/mailbox/mtk-cmdq-mailbox.c | 13 +++++++------
1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/drivers/mailbox/mtk-cmdq-mailbox.c b/drivers/mailbox/mtk-cmdq-mailbox.c
index a460ee26eb11..b18d47ea13a0 100644
--- a/drivers/mailbox/mtk-cmdq-mailbox.c
+++ b/drivers/mailbox/mtk-cmdq-mailbox.c
@@ -569,12 +569,6 @@ static int cmdq_probe(struct platform_device *pdev)
}

cmdq->irq_mask = GENMASK(cmdq->pdata->thread_nr - 1, 0);
- err = devm_request_irq(dev, cmdq->irq, cmdq_irq_handler, IRQF_SHARED,
- "mtk_cmdq", cmdq);
- if (err < 0) {
- dev_err(dev, "failed to register ISR (%d)\n", err);
- return err;
- }

dev_dbg(dev, "cmdq device: addr:0x%p, va:0x%p, irq:%d\n",
dev, cmdq->base, cmdq->irq);
@@ -641,6 +635,13 @@ static int cmdq_probe(struct platform_device *pdev)

cmdq_init(cmdq);

+ err = devm_request_irq(dev, cmdq->irq, cmdq_irq_handler, IRQF_SHARED,
+ "mtk_cmdq", cmdq);
+ if (err < 0) {
+ dev_err(dev, "failed to register ISR (%d)\n", err);
+ return err;
+ }
+
return 0;
}


---
base-commit: 1642107db81361b4339643eb90af4839e2cf229f
change-id: 20221125-mtk-mailbox-ba6cbd1d91b6

Best regards,
--
Ricardo Ribalda <[email protected]>


Subject: Re: [PATCH v3] mailbox: mtk-cmdq: Do not request irq until we are ready

Il 30/11/22 13:58, Ricardo Ribalda ha scritto:
> If the system comes from kexec() the peripheral might trigger an IRQ
> befoe we are ready for it. Triggering a crash due to an access to
> invalid memory.
>
> Signed-off-by: Ricardo Ribalda <[email protected]>

Reviewed-by: AngeloGioacchino Del Regno <[email protected]>


2022-12-06 00:01:01

by Chun-Kuang Hu

[permalink] [raw]
Subject: Re: [PATCH v3] mailbox: mtk-cmdq: Do not request irq until we are ready

Ricardo Ribalda <[email protected]> 於 2022年11月30日 週三 晚上8:59寫道：
>
> If the system comes from kexec() the peripheral might trigger an IRQ
> befoe we are ready for it. Triggering a crash due to an access to
> invalid memory.

Reviewed-by: Chun-Kuang Hu <[email protected]>

>
> Signed-off-by: Ricardo Ribalda <[email protected]>
> ---
> To: AngeloGioacchino Del Regno <[email protected]>
> To: Jassi Brar <[email protected]>
> To: Matthias Brugger <[email protected]>
> Cc: [email protected]
> Cc: [email protected]
> Cc: [email protected]
> ---
> Changes in v3:
> - Rebase on top of https://patchwork.kernel.org/project/linux-mediatek/patch/[email protected]/
> - Link to v2: https://lore.kernel.org/r/[email protected]
>
> Changes in v2:
> - I have managed to repro a different panic. Moving the irq enabling to the very end of probe.
> - Link to v1: https://lore.kernel.org/r/[email protected]
> ---
> drivers/mailbox/mtk-cmdq-mailbox.c | 13 +++++++------
> 1 file changed, 7 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/mailbox/mtk-cmdq-mailbox.c b/drivers/mailbox/mtk-cmdq-mailbox.c
> index a460ee26eb11..b18d47ea13a0 100644
> --- a/drivers/mailbox/mtk-cmdq-mailbox.c
> +++ b/drivers/mailbox/mtk-cmdq-mailbox.c
> @@ -569,12 +569,6 @@ static int cmdq_probe(struct platform_device *pdev)
> }
>
> cmdq->irq_mask = GENMASK(cmdq->pdata->thread_nr - 1, 0);
> - err = devm_request_irq(dev, cmdq->irq, cmdq_irq_handler, IRQF_SHARED,
> - "mtk_cmdq", cmdq);
> - if (err < 0) {
> - dev_err(dev, "failed to register ISR (%d)\n", err);
> - return err;
> - }
>
> dev_dbg(dev, "cmdq device: addr:0x%p, va:0x%p, irq:%d\n",
> dev, cmdq->base, cmdq->irq);
> @@ -641,6 +635,13 @@ static int cmdq_probe(struct platform_device *pdev)
>
> cmdq_init(cmdq);
>
> + err = devm_request_irq(dev, cmdq->irq, cmdq_irq_handler, IRQF_SHARED,
> + "mtk_cmdq", cmdq);
> + if (err < 0) {
> + dev_err(dev, "failed to register ISR (%d)\n", err);
> + return err;
> + }
> +
> return 0;
> }
>
>
> ---
> base-commit: 1642107db81361b4339643eb90af4839e2cf229f
> change-id: 20221125-mtk-mailbox-ba6cbd1d91b6
>
> Best regards,
> --
> Ricardo Ribalda <[email protected]>
>