Re: [PATCH 2/3] scsi: arcmsr: Fix suspend/resume of ACB_ADAPTER_TYPE_B part 2

From: Dan Carpenter
Date: Thu Jan 17 2019 - 03:00:51 EST


On Thu, Jan 17, 2019 at 11:45:03AM +0800, Ching Huang wrote:
> >From Ching Huang <ching2048@xxxxxxxxxxxx>
>
> Fix suspend/resume of ACB_ADAPTER_TYPE_B part 2.
>

What does this look like from a user perspective? Does it fail every
time or does it only fail sometimes?

What's the bug exactly?

There is no Fixes tag...

> Signed-off-by: Ching Huang <ching2048@xxxxxxxxxxxx>
> ---
>
> diff --git a/drivers/scsi/arcmsr/arcmsr.h b/drivers/scsi/arcmsr/arcmsr.h
> index a94c513..b98c632 100755
> --- a/drivers/scsi/arcmsr/arcmsr.h
> +++ b/drivers/scsi/arcmsr/arcmsr.h
> @@ -508,9 +508,9 @@ struct MessageUnit_A
> struct MessageUnit_B
> {
> uint32_t post_qbuffer[ARCMSR_MAX_HBB_POSTQUEUE];
> - uint32_t done_qbuffer[ARCMSR_MAX_HBB_POSTQUEUE];
> + volatile uint32_t done_qbuffer[ARCMSR_MAX_HBB_POSTQUEUE];

There is a well known rule of thumb that when someone uses "volatile"
in the kernel it means there is a locking problem... Is this __iomem or
something?

> uint32_t postq_index;
> - uint32_t doneq_index;
> + volatile uint32_t doneq_index;
> uint32_t __iomem *drv2iop_doorbell;
> uint32_t __iomem *drv2iop_doorbell_mask;
> uint32_t __iomem *iop2drv_doorbell;
> diff --git a/drivers/scsi/arcmsr/arcmsr_hba.c b/drivers/scsi/arcmsr/arcmsr_hba.c
> index 5736434..88053b1 100755
> --- a/drivers/scsi/arcmsr/arcmsr_hba.c
> +++ b/drivers/scsi/arcmsr/arcmsr_hba.c
> @@ -1113,7 +1113,11 @@ static int arcmsr_resume(struct pci_dev *pdev)
> switch (acb->adapter_type) {
> case ACB_ADAPTER_TYPE_B: {
> struct MessageUnit_B *reg = acb->pmuB;
> - reg->post_qbuffer[0] = 0;
> + uint32_t i;
> + for (i = 0; i < ARCMSR_MAX_HBB_POSTQUEUE; i++) {
> + reg->post_qbuffer[i] = 0;
> + reg->done_qbuffer[i] = 0;
> + }

Is this cause by patch 1 changing the zalloc to regular alloc?? If so
then it should be folded into that patch instead of sent separately.

regards,
dan carpenter