Re: Re: [PATCH] scsi: lpfc: use unsigned type for num_sge
From: Daniel Wagner
Date: Wed Jan 17 2024 - 05:56:38 EST
Hi Dick,
On Fri, Dec 22, 2023 at 10:04:50AM -0800, Dick Kennedy wrote:
> The change is good, however, I don't think this was really the
> problem.
I tried to write the commit message based on the bug report we got. So
yes, it's possible the it is not correct as I was not really involved
and might missinterpret it.
> We would like to know if this patch really solved an issue they
> observed.
Yes, it fixes the reported problem.
> A good data point to know is what adapter they're using.
A bunch of different HPE cards which show this log entry: SN1700E,
SN1610E and SN1200E.
> If that adapter supports hybrid sgl (i.e. phba->cfg_xpsgl), then we
> would have set the max sg_tablesize = LPFC_MAX_SG_TABLESIZE = 0xffff.
>
> But even then, this patch implies that dma_map_sg() returned a crazy
> huge amount with the MSB set.
Sure, though this seems to be the case.
One noteworthy information is that DIF needs to be enabled to trigger
it:
# cat /sys/module/lpfc/parameters/lpfc_enable_bg
1
# cat /sys/module/lpfc/parameters/lpfc_prot_guard
2
Thanks,
Daniel