linux-kernel - Re: [PATCH 03/17] hpsa: enable bus master bit after pci_enable

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20120420200652.GA11802@beardog.cce.hp.com>
Date:	Fri, 20 Apr 2012 15:06:52 -0500
From:	scameron@...rdog.cce.hp.com
To:	Khalid Aziz <khalid.aziz@...com>
Cc:	james.bottomley@...senpartnership.com, linux-scsi@...r.kernel.org,
	linux-kernel@...r.kernel.org, matthew.gates@...com,
	stephenmcameron@...il.com, thenzl@...hat.com,
	akpm@...ux-foundation.org, mikem@...rdog.cce.hp.com,
	scameron@...rdog.cce.hp.com
Subject: Re: [PATCH 03/17] hpsa: enable bus master bit after pci_enable_device

On Fri, Apr 20, 2012 at 12:41:50PM -0600, Khalid Aziz wrote:
> On Fri, 2012-04-20 at 10:06 -0500, Stephen M. Cameron wrote:
> > From: Stephen M. Cameron <scameron@...rdog.cce.hp.com>
> > 
> > pci_disable_device() disables the bus master bit and pci_enable_device does
> > not re-enable it.  It needs to be enabled.
> > 
> > Signed-off-by: Stephen M. Cameron <scameron@...rdog.cce.hp.com>
> > ---
> >  drivers/scsi/hpsa.c |    6 ++++++
> >  1 files changed, 6 insertions(+), 0 deletions(-)
> > 
> > diff --git a/drivers/scsi/hpsa.c b/drivers/scsi/hpsa.c
> > index 5119ce6..363619d 100644
> > --- a/drivers/scsi/hpsa.c
> > +++ b/drivers/scsi/hpsa.c
> > @@ -3917,6 +3917,7 @@ static int __devinit hpsa_enter_simple_mode(struct ctlr_info *h)
> >  static int __devinit hpsa_pci_init(struct ctlr_info *h)
> >  {
> >  	int prod_index, err;
> > +	u16 command_register;
> >  
> >  	prod_index = hpsa_lookup_board_id(h->pdev, &h->board_id);
> >  	if (prod_index < 0)
> > @@ -3933,6 +3934,11 @@ static int __devinit hpsa_pci_init(struct ctlr_info *h)
> >  		return err;
> >  	}
> >  
> > +	/* Enable bus mastering (pci_disable_device may disable this) */
> > +	pci_read_config_word(h->pdev, PCI_COMMAND, &command_register);
> > +	command_register |= PCI_COMMAND_MASTER;
> > +	pci_write_config_word(h->pdev, PCI_COMMAND, command_register);
> > +
> >  	err = pci_request_regions(h->pdev, HPSA);
> >  	if (err) {
> >  		dev_err(&h->pdev->dev,
> 
> Wouldn't it be better to use pci_set_master(h->pdev) to enable bus
> mastering?

Yes.  Thanks.

-- steve

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/