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Yi, Shunli

2009-Jul-10 03:57 UTC

[Xen-devel] Drivers cannot write to msix_iomem from DomU, is this right?

Hi:
I''m using the Xen-3.3.1. and I find Xend doesn''t permit the
DomU driver to access the msix_iomem.

"xend/server/pciif.py" : Line :342.
        if dev.msix:
            for (start, size) in dev.msix_iomem:
                start_pfn = start>>PAGE_SHIFT
                nr_pfns = (size+(PAGE_SIZE-1))>>PAGE_SHIFT
                log.debug(''pci-msix: remove permission for 0x%x/0x%x
0x%x/0x%x'' % \
                         (start,size, start_pfn, nr_pfns))
                rc = xc.domain_iomem_permission(domid = fe_domid,
                                                first_pfn = start_pfn,
                                                nr_pfns = nr_pfns,
                                                allow_access = False)

I haven''t wrote any driver code, but I think the driver should can
write messages to the msix_iomem.
Because the driver will write some MSI information to the MSI register.

And I find following code in bnx2-1.8.5b:
File :                       bnx2.c
Version:               1.8.5b
Function:             bnx2_enable_msix()
    bnx2_setup_msix_tbl(bp);
    REG_WR(bp, BNX2_PCI_MSIX_CONTROL, BNX2_MAX_MSIX_HW_VEC - 1);
    REG_WR(bp, BNX2_PCI_MSIX_TBL_OFF_BIR, BNX2_PCI_GRC_WINDOW2_BASE);
REG_WR(bp, BNX2_PCI_MSIX_PBA_OFF_BIT, BNX2_PCI_GRC_WINDOW3_BASE);


So, I think the msix_iomem should be always  writable for the DomU.
Am I Right?


Best Regards!

SHUNLI YI

WEBSENSE NETWORK SECURITY TECHNOLOGY R&D (BEIJING) CO. LTD.
ph: +8610.5884.4142




 Protected by Websense Hosted Email Security -- www.websense.com 


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Jiang, Yunhong

2009-Jul-10 04:56 UTC

head link

RE: [Xen-devel] Drivers cannot write to msix_iomem from DomU, is this right?

The MSI-x will include vector information, which should be resource owned by Xen
HV.
For example, if domU set the vector to be same as another device that owned by
another domain (or dom0), or Xen HV's IPI, then it will cause trouble.

--jyh

________________________________
From: xen-devel-bounces@lists.xensource.com
[mailto:xen-devel-bounces@lists.xensource.com] On Behalf Of Yi, Shunli
Sent: 2009年7月10日 11:57
To: xen-devel@lists.xensource.com
Subject: [Xen-devel] Drivers cannot write to msix_iomem from DomU, is this
right?

Hi:
I’m using the Xen-3.3.1. and I find Xend doesn’t permit the DomU driver to
access the msix_iomem.

"xend/server/pciif.py" : Line :342.
        if dev.msix:
            for (start, size) in dev.msix_iomem:
                start_pfn = start>>PAGE_SHIFT
                nr_pfns = (size+(PAGE_SIZE-1))>>PAGE_SHIFT
                log.debug('pci-msix: remove permission for 0x%x/0x%x
0x%x/0x%x' % \
                         (start,size, start_pfn, nr_pfns))
                rc = xc.domain_iomem_permission(domid = fe_domid,
                                                first_pfn = start_pfn,
                                                nr_pfns = nr_pfns,
                                                allow_access = False)

I haven’t wrote any driver code, but I think the driver should can write
messages to the msix_iomem.
Because the driver will write some MSI information to the MSI register.

And I find following code in bnx2-1.8.5b:
File :                       bnx2.c
Version:               1.8.5b
Function:             bnx2_enable_msix()
    bnx2_setup_msix_tbl(bp);
    REG_WR(bp, BNX2_PCI_MSIX_CONTROL, BNX2_MAX_MSIX_HW_VEC - 1);
    REG_WR(bp, BNX2_PCI_MSIX_TBL_OFF_BIR, BNX2_PCI_GRC_WINDOW2_BASE);
REG_WR(bp, BNX2_PCI_MSIX_PBA_OFF_BIT, BNX2_PCI_GRC_WINDOW3_BASE);


So, I think the msix_iomem should be always  writable for the DomU.
Am I Right?


Best Regards!

SHUNLI YI

WEBSENSE NETWORK SECURITY TECHNOLOGY R&D (BEIJING) CO. LTD.
ph: +8610.5884.4142





Protected by Websense Hosted Email Security — www.websense.com


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Xen-devel@lists.xensource.com
http://lists.xensource.com/xen-devel

Yi, Shunli

2009-Jul-10 05:18 UTC

head link

RE: [Xen-devel] Drivers cannot write to msix_iomem from DomU, is this right?

But how should I to understand the REG_WR() code when load the bnx2 module ?


Best Regards!

SHUNLI YI

WEBSENSE NETWORK SECURITY TECHNOLOGY R&D (BEIJING) CO. LTD.
ph: +8610.5884.4142


From: Jiang, Yunhong [mailto:yunhong.jiang@intel.com]
Sent: 2009年7月10日 12:57
To: Yi, Shunli; xen-devel@lists.xensource.com
Subject: RE: [Xen-devel] Drivers cannot write to msix_iomem from DomU, is this
right?

The MSI-x will include vector information, which should be resource owned by Xen
HV.
For example, if domU set the vector to be same as another device that owned by
another domain (or dom0), or Xen HV's IPI, then it will cause trouble.

--jyh

________________________________
From: xen-devel-bounces@lists.xensource.com
[mailto:xen-devel-bounces@lists.xensource.com] On Behalf Of Yi, Shunli
Sent: 2009年7月10日 11:57
To: xen-devel@lists.xensource.com
Subject: [Xen-devel] Drivers cannot write to msix_iomem from DomU, is this
right?
Hi:
I’m using the Xen-3.3.1. and I find Xend doesn’t permit the DomU driver to
access the msix_iomem.

"xend/server/pciif.py" : Line :342.
        if dev.msix:
            for (start, size) in dev.msix_iomem:
                start_pfn = start>>PAGE_SHIFT
                nr_pfns = (size+(PAGE_SIZE-1))>>PAGE_SHIFT
                log.debug('pci-msix: remove permission for 0x%x/0x%x
0x%x/0x%x' % \
                         (start,size, start_pfn, nr_pfns))
                rc = xc.domain_iomem_permission(domid = fe_domid,
                                                first_pfn = start_pfn,
                                                nr_pfns = nr_pfns,
                                                allow_access = False)

I haven’t wrote any driver code, but I think the driver should can write
messages to the msix_iomem.
Because the driver will write some MSI information to the MSI register.

And I find following code in bnx2-1.8.5b:
File :                       bnx2.c
Version:               1.8.5b
Function:             bnx2_enable_msix()
    bnx2_setup_msix_tbl(bp);
    REG_WR(bp, BNX2_PCI_MSIX_CONTROL, BNX2_MAX_MSIX_HW_VEC - 1);
    REG_WR(bp, BNX2_PCI_MSIX_TBL_OFF_BIR, BNX2_PCI_GRC_WINDOW2_BASE);
REG_WR(bp, BNX2_PCI_MSIX_PBA_OFF_BIT, BNX2_PCI_GRC_WINDOW3_BASE);


So, I think the msix_iomem should be always  writable for the DomU.
Am I Right?


Best Regards!

SHUNLI YI

WEBSENSE NETWORK SECURITY TECHNOLOGY R&D (BEIJING) CO. LTD.
ph: +8610.5884.4142



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Jiang, Yunhong

2009-Jul-10 05:33 UTC

head link

RE: [Xen-devel] Drivers cannot write to msix_iomem from DomU, is this right?

Sorry that I don't know what's bnx and is it a Linux driver?
Basically domU will depends on pci backend to enable MSI/MSI-x.

--jyh

________________________________
From: Yi, Shunli [mailto:syi@websense.com]
Sent: 2009年7月10日 13:19
To: Jiang, Yunhong; xen-devel@lists.xensource.com
Subject: RE: [Xen-devel] Drivers cannot write to msix_iomem from DomU, is this
right?

But how should I to understand the REG_WR() code when load the bnx2 module ?

Best Regards!

SHUNLI YI

WEBSENSE NETWORK SECURITY TECHNOLOGY R&D (BEIJING) CO. LTD.
ph: +8610.5884.4142

From: Jiang, Yunhong [mailto:yunhong.jiang@intel.com]
Sent: 2009年7月10日 12:57
To: Yi, Shunli; xen-devel@lists.xensource.com
Subject: RE: [Xen-devel] Drivers cannot write to msix_iomem from DomU, is this
right?

The MSI-x will include vector information, which should be resource owned by Xen
HV.
For example, if domU set the vector to be same as another device that owned by
another domain (or dom0), or Xen HV's IPI, then it will cause trouble.

--jyh

________________________________
From: xen-devel-bounces@lists.xensource.com
[mailto:xen-devel-bounces@lists.xensource.com] On Behalf Of Yi, Shunli
Sent: 2009年7月10日 11:57
To: xen-devel@lists.xensource.com
Subject: [Xen-devel] Drivers cannot write to msix_iomem from DomU, is this
right?
Hi:
I’m using the Xen-3.3.1. and I find Xend doesn’t permit the DomU driver to
access the msix_iomem.

"xend/server/pciif.py" : Line :342.
        if dev.msix:
            for (start, size) in dev.msix_iomem:
                start_pfn = start>>PAGE_SHIFT
                nr_pfns = (size+(PAGE_SIZE-1))>>PAGE_SHIFT
                log.debug('pci-msix: remove permission for 0x%x/0x%x
0x%x/0x%x' % \
                         (start,size, start_pfn, nr_pfns))
                rc = xc.domain_iomem_permission(domid = fe_domid,
                                                first_pfn = start_pfn,
                                                nr_pfns = nr_pfns,
                                                allow_access = False)

I haven’t wrote any driver code, but I think the driver should can write
messages to the msix_iomem.
Because the driver will write some MSI information to the MSI register.

And I find following code in bnx2-1.8.5b:
File :                       bnx2.c
Version:               1.8.5b
Function:             bnx2_enable_msix()
    bnx2_setup_msix_tbl(bp);
    REG_WR(bp, BNX2_PCI_MSIX_CONTROL, BNX2_MAX_MSIX_HW_VEC - 1);
    REG_WR(bp, BNX2_PCI_MSIX_TBL_OFF_BIR, BNX2_PCI_GRC_WINDOW2_BASE);
REG_WR(bp, BNX2_PCI_MSIX_PBA_OFF_BIT, BNX2_PCI_GRC_WINDOW3_BASE);

So, I think the msix_iomem should be always  writable for the DomU.
Am I Right?

Best Regards!

SHUNLI YI

WEBSENSE NETWORK SECURITY TECHNOLOGY R&D (BEIJING) CO. LTD.
ph: +8610.5884.4142

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Xen devel - Jul 2009 - Drivers cannot write to msix_iomem from DomU, is this right?

[Xen-devel] Drivers cannot write to msix_iomem from DomU, is this right?

RE: [Xen-devel] Drivers cannot write to msix_iomem from DomU, is this right?

RE: [Xen-devel] Drivers cannot write to msix_iomem from DomU, is this right?

RE: [Xen-devel] Drivers cannot write to msix_iomem from DomU, is this right?