All of lore.kernel.org
 help / color / mirror / Atom feed
From: Christoph Hellwig <hch@infradead.org>
To: Suganath Prabu <suganath-prabu.subramani@broadcom.com>
Cc: linux-scsi@vger.kernel.org, stable@vger.kernel.org,
	Sathya.Prakash@broadcom.com, kashyap.desai@broadcom.com,
	sreekanth.reddy@broadcom.com
Subject: Re: [PATCH] mpt3sas: Use 63-bit DMA addressing on SAS35 HBA
Date: Fri, 26 Jul 2019 07:27:06 -0700	[thread overview]
Message-ID: <20190726142706.GA1734@infradead.org> (raw)
In-Reply-To: <1564135257-33188-1-git-send-email-suganath-prabu.subramani@broadcom.com>

On Fri, Jul 26, 2019 at 06:00:57AM -0400, Suganath Prabu wrote:
> Although SAS3 & SAS3.5 IT HBA controllers support
> 64-bit DMA addressing, as per hardware design,
> DMA address with all 64-bits set (0xFFFFFFFF-FFFFFFFF)
> results in a firmware fault.

Linux will never send a dma address with all bits set anyway, as that
is our magic escape for the dma_addr_t error value.  Additionally to
generate that address you'd need a 1-byte sized, 1-byte aligned buffer,
which we never use.

  parent reply	other threads:[~2019-07-26 14:27 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-07-26 10:00 [PATCH] mpt3sas: Use 63-bit DMA addressing on SAS35 HBA Suganath Prabu
2019-07-26 10:20 ` Greg KH
2019-07-26 14:27 ` Christoph Hellwig [this message]
2019-07-29 11:55   ` Sreekanth Reddy
2019-07-30  6:38     ` Christoph Hellwig
2019-07-31  9:58 Suganath Prabu
2019-07-31  9:58 ` Suganath Prabu
2019-08-05 11:59   ` Greg KH
2019-07-31 10:08 ` Greg KH

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20190726142706.GA1734@infradead.org \
    --to=hch@infradead.org \
    --cc=Sathya.Prakash@broadcom.com \
    --cc=kashyap.desai@broadcom.com \
    --cc=linux-scsi@vger.kernel.org \
    --cc=sreekanth.reddy@broadcom.com \
    --cc=stable@vger.kernel.org \
    --cc=suganath-prabu.subramani@broadcom.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.