From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([140.186.70.92]:38087) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1QwCwb-0005wB-7T for qemu-devel@nongnu.org; Wed, 24 Aug 2011 08:52:34 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1QwCwZ-0004SJ-OY for qemu-devel@nongnu.org; Wed, 24 Aug 2011 08:52:33 -0400 Received: from mx1.redhat.com ([209.132.183.28]:21184) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1QwCwZ-0004S9-A1 for qemu-devel@nongnu.org; Wed, 24 Aug 2011 08:52:31 -0400 Date: Wed, 24 Aug 2011 15:53:21 +0300 From: "Michael S. Tsirkin" Message-ID: <20110824125321.GA18920@redhat.com> References: <4E53E328.90601@siemens.com> <4E54EEAA.7020707@siemens.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4E54EEAA.7020707@siemens.com> Subject: Re: [Qemu-devel] [PATCH v2] pci: Error on PCI capability collisions List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Jan Kiszka Cc: Alex Williamson , "ddutile@redhat.com" , qemu-devel On Wed, Aug 24, 2011 at 02:29:30PM +0200, Jan Kiszka wrote: > Nothing good can happen when we overlap capabilities. This may happen > when plugging in assigned devices or when devices models contain bugs. > Detect the overlap and report it. > > Based on qemu-kvm commit by Alex Williamson. > > Signed-off-by: Jan Kiszka Applied, thanks everyone. > --- > hw/pci.c | 34 ++++++++++++++++++++++++++++++++++ > 1 files changed, 34 insertions(+), 0 deletions(-) > > Changes in v2: > - properly find the conflicting CAP > - adjust error code > > diff --git a/hw/pci.c b/hw/pci.c > index 6124790..634e789 100644 > --- a/hw/pci.c > +++ b/hw/pci.c > @@ -1811,6 +1811,25 @@ static uint8_t pci_find_capability_list(PCIDevice *pdev, uint8_t cap_id, > return next; > } > > +static uint8_t pci_find_capability_at_offset(PCIDevice *pdev, uint8_t offset) > +{ > + uint8_t next, prev, found = 0; > + > + if (!(pdev->used[offset])) { > + return 0; > + } > + > + assert(pdev->config[PCI_STATUS] & PCI_STATUS_CAP_LIST); > + > + for (prev = PCI_CAPABILITY_LIST; (next = pdev->config[prev]); > + prev = next + PCI_CAP_LIST_NEXT) { > + if (next <= offset && next > found) { > + found = next; > + } > + } > + return found; > +} > + > /* Patch the PCI vendor and device ids in a PCI rom image if necessary. > This is needed for an option rom which is used for more than one device. */ > static void pci_patch_ids(PCIDevice *pdev, uint8_t *ptr, int size) > @@ -1952,11 +1971,26 @@ int pci_add_capability(PCIDevice *pdev, uint8_t cap_id, > uint8_t offset, uint8_t size) > { > uint8_t *config; > + int i, overlapping_cap; > + > if (!offset) { > offset = pci_find_space(pdev, size); > if (!offset) { > return -ENOSPC; > } > + } else { > + for (i = offset; i < offset + size; i++) { > + overlapping_cap = pci_find_capability_at_offset(pdev, i); > + if (overlapping_cap) { > + fprintf(stderr, "ERROR: %04x:%02x:%02x.%x " > + "Attempt to add PCI capability %x at offset " > + "%x overlaps existing capability %x at offset %x\n", > + pci_find_domain(pdev->bus), pci_bus_num(pdev->bus), > + PCI_SLOT(pdev->devfn), PCI_FUNC(pdev->devfn), > + cap_id, offset, overlapping_cap, i); > + return -EINVAL; > + } > + } > } > > config = pdev->config + offset; > -- > 1.7.3.4