linux-kernel - Re: [PATCH 1/2, pci] pci: Addition of PCI_DEV_FLAGS_QUIET_PCI

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: <20180314180642.GC179719@bhelgaas-glaptop.roam.corp.google.com>
Date:   Wed, 14 Mar 2018 13:06:42 -0500
From:   Bjorn Helgaas <helgaas@...nel.org>
To:     "Desnes A. Nunes do Rosario" <desnesn@...ux.vnet.ibm.com>
Cc:     linux-kernel@...r.kernel.org, linux-pci@...r.kernel.org,
        linuxppc-dev@...ts.ozlabs.org, bhelgaas@...gle.com,
        benh@...nel.crashing.org, paulus@...ba.org, mpe@...erman.id.au,
        ruscur@...sell.cc, aik@...abs.ru, david@...son.dropbear.id.au,
        fbarrat@...ux.vnet.ibm.com, brking@...ux.vnet.ibm.com
Subject: Re: [PATCH 1/2, pci] pci: Addition of
 PCI_DEV_FLAGS_QUIET_PCI_REALIGN attribute to the PCI subsystem

On Wed, Mar 14, 2018 at 01:34:54PM -0300, Desnes A. Nunes do Rosario wrote:
> Add PCI_DEV_FLAGS_QUIET_PCI_REALIGN to pci_dev_flags and use it to
> silent PCI realignment messages if the flag is turned on by a driver.
> 
> Signed-off-by: Desnes A. Nunes do Rosario <desnesn@...ux.vnet.ibm.com>
> ---
>  drivers/pci/pci.c       | 3 ++-
>  drivers/pci/setup-res.c | 3 ++-
>  include/linux/pci.h     | 2 ++
>  3 files changed, 6 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
> index 8c71d1a66cdd..be197c944e5f 100644
> --- a/drivers/pci/pci.c
> +++ b/drivers/pci/pci.c
> @@ -5505,7 +5505,8 @@ void pci_reassigndev_resource_alignment(struct pci_dev *dev)
>  		return;
>  	}
>  
> -	pci_info(dev, "Disabling memory decoding and releasing memory resources\n");
> +	if (!(dev->dev_flags & PCI_DEV_FLAGS_QUIET_PCI_REALIGN))
> +		pci_info(dev, "Disabling memory decoding and releasing memory resources\n");
>  	pci_read_config_word(dev, PCI_COMMAND, &command);
>  	command &= ~PCI_COMMAND_MEMORY;
>  	pci_write_config_word(dev, PCI_COMMAND, command);
> diff --git a/drivers/pci/setup-res.c b/drivers/pci/setup-res.c
> index 369d48d6c6f1..00a538def763 100644
> --- a/drivers/pci/setup-res.c
> +++ b/drivers/pci/setup-res.c
> @@ -172,7 +172,8 @@ EXPORT_SYMBOL(pci_claim_resource);
>  
>  void pci_disable_bridge_window(struct pci_dev *dev)
>  {
> -	pci_info(dev, "disabling bridge mem windows\n");
> +	if (!(dev->dev_flags & PCI_DEV_FLAGS_QUIET_PCI_REALIGN))
> +		pci_info(dev, "disabling bridge mem windows\n");

As far as I'm concerned, we can just remove these messages completely.
I don't think there's any real value there.

>  	/* MMIO Base/Limit */
>  	pci_write_config_dword(dev, PCI_MEMORY_BASE, 0x0000fff0);
> diff --git a/include/linux/pci.h b/include/linux/pci.h
> index e057e8cc63e7..993f9c7dcc00 100644
> --- a/include/linux/pci.h
> +++ b/include/linux/pci.h
> @@ -205,6 +205,8 @@ enum pci_dev_flags {
>  	PCI_DEV_FLAGS_NO_FLR_RESET = (__force pci_dev_flags_t) (1 << 10),
>  	/* Don't use Relaxed Ordering for TLPs directed at this device */
>  	PCI_DEV_FLAGS_NO_RELAXED_ORDERING = (__force pci_dev_flags_t) (1 << 11),
> +	/* Silent PCI resource realignment messages */
> +	PCI_DEV_FLAGS_QUIET_PCI_REALIGN = (__force pci_dev_flags_t) (1 << 12),
>  };
>  
>  enum pci_irq_reroute_variant {
> -- 
> 2.14.3
>