linux-kernel - Re: [RFC PATCH 1/5] pci/p2p: add a function to test peer to peer capability

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]

Date:   Tue, 29 Jan 2019 11:24:09 -0700
From:   Logan Gunthorpe <logang@...tatee.com>
To:     jglisse@...hat.com, linux-mm@...ck.org
Cc:     linux-kernel@...r.kernel.org,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        "Rafael J . Wysocki" <rafael@...nel.org>,
        Bjorn Helgaas <bhelgaas@...gle.com>,
        Christian Koenig <christian.koenig@....com>,
        Felix Kuehling <Felix.Kuehling@....com>,
        Jason Gunthorpe <jgg@...lanox.com>, linux-pci@...r.kernel.org,
        dri-devel@...ts.freedesktop.org, Christoph Hellwig <hch@....de>,
        Marek Szyprowski <m.szyprowski@...sung.com>,
        Robin Murphy <robin.murphy@....com>,
        Joerg Roedel <jroedel@...e.de>,
        iommu@...ts.linux-foundation.org
Subject: Re: [RFC PATCH 1/5] pci/p2p: add a function to test peer to peer
 capability



On 2019-01-29 10:47 a.m., jglisse@...hat.com wrote:
> +bool pci_test_p2p(struct device *devA, struct device *devB)
> +{
> +	struct pci_dev *pciA, *pciB;
> +	bool ret;
> +	int tmp;
> +
> +	/*
> +	 * For now we only support PCIE peer to peer but other inter-connect
> +	 * can be added.
> +	 */
> +	pciA = find_parent_pci_dev(devA);
> +	pciB = find_parent_pci_dev(devB);
> +	if (pciA == NULL || pciB == NULL) {
> +		ret = false;
> +		goto out;
> +	}
> +
> +	tmp = upstream_bridge_distance(pciA, pciB, NULL);
> +	ret = tmp < 0 ? false : true;
> +
> +out:
> +	pci_dev_put(pciB);
> +	pci_dev_put(pciA);
> +	return false;
> +}
> +EXPORT_SYMBOL_GPL(pci_test_p2p);

This function only ever returns false....

Logan