[PATCH] libxl_pci: check that host device is assignable before adding to the domain

[PATCH] libxl_pci: check that host device is assignable before adding to the domain

[Doug Magee]

Previously, on ..._pci_add, libxl only checks that a device is not assigned to another domain. This quick patch checks that the device is also owned by pciback, otherwise the call fails.

Signed-off-by: Doug Magee <djmagee@mageenet.net>

diff -r 5b2676ac1321 -r 301cc006677f tools/libxl/libxl_pci.c
--- a/tools/libxl/libxl_pci.c	Mon Jan 09 16:01:44 2012 +0100
+++ b/tools/libxl/libxl_pci.c	Mon Jan 16 17:31:25 2012 -0500
@@ -796,6 +796,9 @@ int libxl__device_pci_add(libxl__gc *gc,
     libxl_device_pci *assigned;
     int num_assigned, i, rc;
     int stubdomid = 0;
+    struct dirent *de;
+    DIR *dir;
+    int assignable = 0;
 
     rc = get_all_assigned_devices(gc, &assigned, &num_assigned);
     if ( rc ) {
@@ -809,6 +812,35 @@ int libxl__device_pci_add(libxl__gc *gc,
         goto out;
     }
 
+    dir = opendir(SYSFS_PCIBACK_DRIVER);
+    if ( NULL == dir ) {
+        if ( errno == ENOENT ) {
+            LIBXL__LOG(ctx, LIBXL__LOG_ERROR, "Looks like pciback driver not loaded");
+        }else{
+            LIBXL__LOG_ERRNO(ctx, LIBXL__LOG_ERROR, "Couldn't open %s", SYSFS_PCIBACK_DRIVER);
+        }
+        rc = ERROR_FAIL;
+        goto out_closedir;
+    }
+
+    while( (de = readdir(dir)) ) {
+        unsigned dom, bus, dev, func;
+        if ( sscanf(de->d_name, PCI_BDF, &dom, &bus, &dev, &func) != 4 )
+            continue;
+        if ( dom == pcidev->domain && bus == pcidev->bus &&
+              dev == pcidev->dev && func == pcidev->func ) {
+            assignable = 1;
+            break;
+        }
+    }
+
+    if ( !assignable ) {
+        rc = ERROR_FAIL;
+        LIBXL__LOG(ctx, LIBXL__LOG_ERROR, "PCI device not owned by pciback");
+        goto out_closedir;
+    }
+
+
     libxl__device_pci_reset(gc, pcidev->domain, pcidev->bus, pcidev->dev, pcidev->func);
 
     stubdomid = libxl_get_stubdom_id(ctx, domid);
@@ -817,7 +849,7 @@ int libxl__device_pci_add(libxl__gc *gc,
         /* stubdomain is always running by now, even at create time */
         rc = do_pci_add(gc, stubdomid, &pcidev_s, 0);
         if ( rc )
-            goto out;
+            goto out_closedir;
     }
 
     orig_vdev = pcidev->vdevfn & ~7U;
@@ -826,11 +858,11 @@ int libxl__device_pci_add(libxl__gc *gc,
         if ( !(pcidev->vdevfn >> 3) ) {
             LIBXL__LOG(ctx, LIBXL__LOG_ERROR, "Must specify a v-slot for multi-function devices");
             rc = ERROR_INVAL;
-            goto out;
+            goto out_closedir;
         }
         if ( pci_multifunction_check(gc, pcidev, &pfunc_mask) ) {
             rc = ERROR_FAIL;
-            goto out;
+            goto out_closedir;
         }
         pcidev->vfunc_mask &= pfunc_mask;
         /* so now vfunc_mask == pfunc_mask */
@@ -855,6 +887,8 @@ int libxl__device_pci_add(libxl__gc *gc,
         }
     }
 
+out_closedir:
+    closedir(dir);
 out:
     return rc;
 }

Re: [PATCH] libxl_pci: check that host device is assignable before adding to the domain

[Ian Campbell]

On Mon, 2012-01-16 at 22:36 +0000, Doug Magee wrote:
> Previously, on ..._pci_add, libxl only checks that a device is not assigned to another domain. This quick patch checks that the device is also owned by pciback, otherwise the call fails.
> 
> Signed-off-by: Doug Magee <djmagee@mageenet.net>

Thanks Doug. Would this be better done by adding a call to
libxl_device_pci_list_assignable and looking for the device in it? In
fact from the looks of things this could replace the existing call to
get_all_assigned_devices from .._pci_add since
libxl_device_pci_list_assignable already omits devices which are
assigned to another domain.

Ian.

> 
> diff -r 5b2676ac1321 -r 301cc006677f tools/libxl/libxl_pci.c
> --- a/tools/libxl/libxl_pci.c	Mon Jan 09 16:01:44 2012 +0100
> +++ b/tools/libxl/libxl_pci.c	Mon Jan 16 17:31:25 2012 -0500
> @@ -796,6 +796,9 @@ int libxl__device_pci_add(libxl__gc *gc,
>      libxl_device_pci *assigned;
>      int num_assigned, i, rc;
>      int stubdomid = 0;
> +    struct dirent *de;
> +    DIR *dir;
> +    int assignable = 0;
>  
>      rc = get_all_assigned_devices(gc, &assigned, &num_assigned);
>      if ( rc ) {
> @@ -809,6 +812,35 @@ int libxl__device_pci_add(libxl__gc *gc,
>          goto out;
>      }
>  
> +    dir = opendir(SYSFS_PCIBACK_DRIVER);
> +    if ( NULL == dir ) {
> +        if ( errno == ENOENT ) {
> +            LIBXL__LOG(ctx, LIBXL__LOG_ERROR, "Looks like pciback driver not loaded");
> +        }else{
> +            LIBXL__LOG_ERRNO(ctx, LIBXL__LOG_ERROR, "Couldn't open %s", SYSFS_PCIBACK_DRIVER);
> +        }
> +        rc = ERROR_FAIL;
> +        goto out_closedir;
> +    }
> +
> +    while( (de = readdir(dir)) ) {
> +        unsigned dom, bus, dev, func;
> +        if ( sscanf(de->d_name, PCI_BDF, &dom, &bus, &dev, &func) != 4 )
> +            continue;
> +        if ( dom == pcidev->domain && bus == pcidev->bus &&
> +              dev == pcidev->dev && func == pcidev->func ) {
> +            assignable = 1;
> +            break;
> +        }
> +    }
> +
> +    if ( !assignable ) {
> +        rc = ERROR_FAIL;
> +        LIBXL__LOG(ctx, LIBXL__LOG_ERROR, "PCI device not owned by pciback");
> +        goto out_closedir;
> +    }
> +
> +
>      libxl__device_pci_reset(gc, pcidev->domain, pcidev->bus, pcidev->dev, pcidev->func);
>  
>      stubdomid = libxl_get_stubdom_id(ctx, domid);
> @@ -817,7 +849,7 @@ int libxl__device_pci_add(libxl__gc *gc,
>          /* stubdomain is always running by now, even at create time */
>          rc = do_pci_add(gc, stubdomid, &pcidev_s, 0);
>          if ( rc )
> -            goto out;
> +            goto out_closedir;
>      }
>  
>      orig_vdev = pcidev->vdevfn & ~7U;
> @@ -826,11 +858,11 @@ int libxl__device_pci_add(libxl__gc *gc,
>          if ( !(pcidev->vdevfn >> 3) ) {
>              LIBXL__LOG(ctx, LIBXL__LOG_ERROR, "Must specify a v-slot for multi-function devices");
>              rc = ERROR_INVAL;
> -            goto out;
> +            goto out_closedir;
>          }
>          if ( pci_multifunction_check(gc, pcidev, &pfunc_mask) ) {
>              rc = ERROR_FAIL;
> -            goto out;
> +            goto out_closedir;
>          }
>          pcidev->vfunc_mask &= pfunc_mask;
>          /* so now vfunc_mask == pfunc_mask */
> @@ -855,6 +887,8 @@ int libxl__device_pci_add(libxl__gc *gc,
>          }
>      }
>  
> +out_closedir:
> +    closedir(dir);
>  out:
>      return rc;
>  }
> 
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@lists.xensource.com
> http://lists.xensource.com/xen-devel

Re: [PATCH] libxl_pci: check that host device is assignable before adding to the domain

[djmagee]

That was my first thought, but this was also the first thing in libxl I touched and wasn't sure what would happen if I ended up nesting GC_INITs.  If it's safe to do then I can call libxl_device_pci_list_assignable, otherwise I'd have to pull the meat out and put it in another function.  What's the best way to do it?

Doug

-----Original Message-----
From: Ian Campbell [mailto:Ian.Campbell@citrix.com] 
Sent: Tuesday, January 17, 2012 4:47 AM
To: djmagee@mageenet.net
Cc: xen-devel@lists.xensource.com; Ian Jackson; Stefano Stabellini
Subject: Re: [Xen-devel] [PATCH] libxl_pci: check that host device is assignable before adding to the domain

On Mon, 2012-01-16 at 22:36 +0000, Doug Magee wrote:
> Previously, on ..._pci_add, libxl only checks that a device is not assigned to another domain. This quick patch checks that the device is also owned by pciback, otherwise the call fails.
> 
> Signed-off-by: Doug Magee <djmagee@mageenet.net>

Thanks Doug. Would this be better done by adding a call to
libxl_device_pci_list_assignable and looking for the device in it? In
fact from the looks of things this could replace the existing call to
get_all_assigned_devices from .._pci_add since
libxl_device_pci_list_assignable already omits devices which are
assigned to another domain.

Ian.

> 
> diff -r 5b2676ac1321 -r 301cc006677f tools/libxl/libxl_pci.c
> --- a/tools/libxl/libxl_pci.c	Mon Jan 09 16:01:44 2012 +0100
> +++ b/tools/libxl/libxl_pci.c	Mon Jan 16 17:31:25 2012 -0500
> @@ -796,6 +796,9 @@ int libxl__device_pci_add(libxl__gc *gc,
>      libxl_device_pci *assigned;
>      int num_assigned, i, rc;
>      int stubdomid = 0;
> +    struct dirent *de;
> +    DIR *dir;
> +    int assignable = 0;
>  
>      rc = get_all_assigned_devices(gc, &assigned, &num_assigned);
>      if ( rc ) {
> @@ -809,6 +812,35 @@ int libxl__device_pci_add(libxl__gc *gc,
>          goto out;
>      }
>  
> +    dir = opendir(SYSFS_PCIBACK_DRIVER);
> +    if ( NULL == dir ) {
> +        if ( errno == ENOENT ) {
> +            LIBXL__LOG(ctx, LIBXL__LOG_ERROR, "Looks like pciback driver not loaded");
> +        }else{
> +            LIBXL__LOG_ERRNO(ctx, LIBXL__LOG_ERROR, "Couldn't open %s", SYSFS_PCIBACK_DRIVER);
> +        }
> +        rc = ERROR_FAIL;
> +        goto out_closedir;
> +    }
> +
> +    while( (de = readdir(dir)) ) {
> +        unsigned dom, bus, dev, func;
> +        if ( sscanf(de->d_name, PCI_BDF, &dom, &bus, &dev, &func) != 4 )
> +            continue;
> +        if ( dom == pcidev->domain && bus == pcidev->bus &&
> +              dev == pcidev->dev && func == pcidev->func ) {
> +            assignable = 1;
> +            break;
> +        }
> +    }
> +
> +    if ( !assignable ) {
> +        rc = ERROR_FAIL;
> +        LIBXL__LOG(ctx, LIBXL__LOG_ERROR, "PCI device not owned by pciback");
> +        goto out_closedir;
> +    }
> +
> +
>      libxl__device_pci_reset(gc, pcidev->domain, pcidev->bus, pcidev->dev, pcidev->func);
>  
>      stubdomid = libxl_get_stubdom_id(ctx, domid);
> @@ -817,7 +849,7 @@ int libxl__device_pci_add(libxl__gc *gc,
>          /* stubdomain is always running by now, even at create time */
>          rc = do_pci_add(gc, stubdomid, &pcidev_s, 0);
>          if ( rc )
> -            goto out;
> +            goto out_closedir;
>      }
>  
>      orig_vdev = pcidev->vdevfn & ~7U;
> @@ -826,11 +858,11 @@ int libxl__device_pci_add(libxl__gc *gc,
>          if ( !(pcidev->vdevfn >> 3) ) {
>              LIBXL__LOG(ctx, LIBXL__LOG_ERROR, "Must specify a v-slot for multi-function devices");
>              rc = ERROR_INVAL;
> -            goto out;
> +            goto out_closedir;
>          }
>          if ( pci_multifunction_check(gc, pcidev, &pfunc_mask) ) {
>              rc = ERROR_FAIL;
> -            goto out;
> +            goto out_closedir;
>          }
>          pcidev->vfunc_mask &= pfunc_mask;
>          /* so now vfunc_mask == pfunc_mask */
> @@ -855,6 +887,8 @@ int libxl__device_pci_add(libxl__gc *gc,
>          }
>      }
>  
> +out_closedir:
> +    closedir(dir);
>  out:
>      return rc;
>  }
> 
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@lists.xensource.com
> http://lists.xensource.com/xen-devel

Re: [PATCH] libxl_pci: check that host device is assignable before adding to the domain

[Ian Campbell]

Please don't top post.

On Tue, 2012-01-17 at 14:05 +0000, djmagee@mageenet.net wrote:
> That was my first thought, but this was also the first thing in libxl
> I touched and wasn't sure what would happen if I ended up nesting
> GC_INITs.  If it's safe to do then I can call
> libxl_device_pci_list_assignable, otherwise I'd have to pull the meat
> out and put it in another function.  What's the best way to do it?

You can use libxl__gc_owner(gc) (or the helpful CTX macro) to get a ctx
from a gc which you use to call an externally visible function from
within libxl -- it'll do the right thing (TM).

Ian.

> 
> Doug
> 
> -----Original Message-----
> From: Ian Campbell [mailto:Ian.Campbell@citrix.com] 
> Sent: Tuesday, January 17, 2012 4:47 AM
> To: djmagee@mageenet.net
> Cc: xen-devel@lists.xensource.com; Ian Jackson; Stefano Stabellini
> Subject: Re: [Xen-devel] [PATCH] libxl_pci: check that host device is assignable before adding to the domain
> 
> On Mon, 2012-01-16 at 22:36 +0000, Doug Magee wrote:
> > Previously, on ..._pci_add, libxl only checks that a device is not assigned to another domain. This quick patch checks that the device is also owned by pciback, otherwise the call fails.
> > 
> > Signed-off-by: Doug Magee <djmagee@mageenet.net>
> 
> Thanks Doug. Would this be better done by adding a call to
> libxl_device_pci_list_assignable and looking for the device in it? In
> fact from the looks of things this could replace the existing call to
> get_all_assigned_devices from .._pci_add since
> libxl_device_pci_list_assignable already omits devices which are
> assigned to another domain.
> 
> Ian.
> 
> > 
> > diff -r 5b2676ac1321 -r 301cc006677f tools/libxl/libxl_pci.c
> > --- a/tools/libxl/libxl_pci.c	Mon Jan 09 16:01:44 2012 +0100
> > +++ b/tools/libxl/libxl_pci.c	Mon Jan 16 17:31:25 2012 -0500
> > @@ -796,6 +796,9 @@ int libxl__device_pci_add(libxl__gc *gc,
> >      libxl_device_pci *assigned;
> >      int num_assigned, i, rc;
> >      int stubdomid = 0;
> > +    struct dirent *de;
> > +    DIR *dir;
> > +    int assignable = 0;
> >  
> >      rc = get_all_assigned_devices(gc, &assigned, &num_assigned);
> >      if ( rc ) {
> > @@ -809,6 +812,35 @@ int libxl__device_pci_add(libxl__gc *gc,
> >          goto out;
> >      }
> >  
> > +    dir = opendir(SYSFS_PCIBACK_DRIVER);
> > +    if ( NULL == dir ) {
> > +        if ( errno == ENOENT ) {
> > +            LIBXL__LOG(ctx, LIBXL__LOG_ERROR, "Looks like pciback driver not loaded");
> > +        }else{
> > +            LIBXL__LOG_ERRNO(ctx, LIBXL__LOG_ERROR, "Couldn't open %s", SYSFS_PCIBACK_DRIVER);
> > +        }
> > +        rc = ERROR_FAIL;
> > +        goto out_closedir;
> > +    }
> > +
> > +    while( (de = readdir(dir)) ) {
> > +        unsigned dom, bus, dev, func;
> > +        if ( sscanf(de->d_name, PCI_BDF, &dom, &bus, &dev, &func) != 4 )
> > +            continue;
> > +        if ( dom == pcidev->domain && bus == pcidev->bus &&
> > +              dev == pcidev->dev && func == pcidev->func ) {
> > +            assignable = 1;
> > +            break;
> > +        }
> > +    }
> > +
> > +    if ( !assignable ) {
> > +        rc = ERROR_FAIL;
> > +        LIBXL__LOG(ctx, LIBXL__LOG_ERROR, "PCI device not owned by pciback");
> > +        goto out_closedir;
> > +    }
> > +
> > +
> >      libxl__device_pci_reset(gc, pcidev->domain, pcidev->bus, pcidev->dev, pcidev->func);
> >  
> >      stubdomid = libxl_get_stubdom_id(ctx, domid);
> > @@ -817,7 +849,7 @@ int libxl__device_pci_add(libxl__gc *gc,
> >          /* stubdomain is always running by now, even at create time */
> >          rc = do_pci_add(gc, stubdomid, &pcidev_s, 0);
> >          if ( rc )
> > -            goto out;
> > +            goto out_closedir;
> >      }
> >  
> >      orig_vdev = pcidev->vdevfn & ~7U;
> > @@ -826,11 +858,11 @@ int libxl__device_pci_add(libxl__gc *gc,
> >          if ( !(pcidev->vdevfn >> 3) ) {
> >              LIBXL__LOG(ctx, LIBXL__LOG_ERROR, "Must specify a v-slot for multi-function devices");
> >              rc = ERROR_INVAL;
> > -            goto out;
> > +            goto out_closedir;
> >          }
> >          if ( pci_multifunction_check(gc, pcidev, &pfunc_mask) ) {
> >              rc = ERROR_FAIL;
> > -            goto out;
> > +            goto out_closedir;
> >          }
> >          pcidev->vfunc_mask &= pfunc_mask;
> >          /* so now vfunc_mask == pfunc_mask */
> > @@ -855,6 +887,8 @@ int libxl__device_pci_add(libxl__gc *gc,
> >          }
> >      }
> >  
> > +out_closedir:
> > +    closedir(dir);
> >  out:
> >      return rc;
> >  }
> > 
> > _______________________________________________
> > Xen-devel mailing list
> > Xen-devel@lists.xensource.com
> > http://lists.xensource.com/xen-devel
> 
> 

Re: [PATCH] libxl_pci: check that host device is assignable before adding to the domain

[djmagee]

> -----Original Message-----
> From: Ian Campbell [mailto:Ian.Campbell@citrix.com]
> Sent: Tuesday, January 17, 2012 9:16 AM
> To: djmagee@mageenet.net
> Cc: xen-devel@lists.xensource.com; Ian Jackson; Stefano Stabellini
> Subject: RE: [Xen-devel] [PATCH] libxl_pci: check that host device is
> assignable before adding to the domain
> 
> Please don't top post.
> 
> On Tue, 2012-01-17 at 14:05 +0000, djmagee@mageenet.net wrote:
> > That was my first thought, but this was also the first thing in libxl
> > I touched and wasn't sure what would happen if I ended up nesting
> > GC_INITs.  If it's safe to do then I can call
> > libxl_device_pci_list_assignable, otherwise I'd have to pull the meat
> > out and put it in another function.  What's the best way to do it?
> 
> You can use libxl__gc_owner(gc) (or the helpful CTX macro) to get a ctx
> from a gc which you use to call an externally visible function from
> within libxl -- it'll do the right thing (TM).

Cool, I'll send an updated patch along today.

Doug

> 
> Ian.
> 

Re: [PATCH] libxl_pci: check that host device is assignable before adding to the domain

[Konrad Rzeszutek Wilk]

On Tue, Jan 17, 2012 at 09:24:39AM -0500, djmagee@mageenet.net wrote:
> > -----Original Message-----
> > From: Ian Campbell [mailto:Ian.Campbell@citrix.com]
> > Sent: Tuesday, January 17, 2012 9:16 AM
> > To: djmagee@mageenet.net
> > Cc: xen-devel@lists.xensource.com; Ian Jackson; Stefano Stabellini
> > Subject: RE: [Xen-devel] [PATCH] libxl_pci: check that host device is
> > assignable before adding to the domain
> > 
> > Please don't top post.
> > 
> > On Tue, 2012-01-17 at 14:05 +0000, djmagee@mageenet.net wrote:
> > > That was my first thought, but this was also the first thing in libxl
> > > I touched and wasn't sure what would happen if I ended up nesting
> > > GC_INITs.  If it's safe to do then I can call
> > > libxl_device_pci_list_assignable, otherwise I'd have to pull the meat
> > > out and put it in another function.  What's the best way to do it?
> > 
> > You can use libxl__gc_owner(gc) (or the helpful CTX macro) to get a ctx
> > from a gc which you use to call an externally visible function from
> > within libxl -- it'll do the right thing (TM).
> 
> Cool, I'll send an updated patch along today.

You might want to check for 'xen-pciback', 'pciback' and 'pci-stub'
as they are valid.
> 
> Doug
> 
> > 
> > Ian.
> > 
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@lists.xensource.com
> http://lists.xensource.com/xen-devel

Re: [PATCH] libxl_pci: check that host device is assignable before adding to the domain

[djmagee]

> -----Original Message-----
> From: Konrad Rzeszutek Wilk [mailto:konrad@darnok.org]
> Sent: Tuesday, January 17, 2012 3:13 PM
> To: djmagee@mageenet.net
> Cc: Ian Campbell; xen-devel@lists.xensource.com; Ian Jackson; Stefano
> Stabellini
> Subject: Re: [Xen-devel] [PATCH] libxl_pci: check that host device is
> assignable before adding to the domain
> 
> On Tue, Jan 17, 2012 at 09:24:39AM -0500, djmagee@mageenet.net wrote:
> > > -----Original Message-----
> > > From: Ian Campbell [mailto:Ian.Campbell@citrix.com]
> > > Sent: Tuesday, January 17, 2012 9:16 AM
> > > To: djmagee@mageenet.net
> > > Cc: xen-devel@lists.xensource.com; Ian Jackson; Stefano Stabellini
> > > Subject: RE: [Xen-devel] [PATCH] libxl_pci: check that host device
> is
> > > assignable before adding to the domain
> > >
> > > Please don't top post.
> > >
> > > On Tue, 2012-01-17 at 14:05 +0000, djmagee@mageenet.net wrote:
> > > > That was my first thought, but this was also the first thing in
> libxl
> > > > I touched and wasn't sure what would happen if I ended up
nesting
> > > > GC_INITs.  If it's safe to do then I can call
> > > > libxl_device_pci_list_assignable, otherwise I'd have to pull the
> meat
> > > > out and put it in another function.  What's the best way to do
> it?
> > >
> > > You can use libxl__gc_owner(gc) (or the helpful CTX macro) to get
a
> ctx
> > > from a gc which you use to call an externally visible function
from
> > > within libxl -- it'll do the right thing (TM).
> >
> > Cool, I'll send an updated patch along today.
> 
> You might want to check for 'xen-pciback', 'pciback' and 'pci-stub'
> as they are valid.

Agreed. I posted an updated patch that calls ..._list_assignable instead
of looping through the directory itself.  I'll work on a separate patch
to update that function to check all applicable places.

In the 3.2.1 kernel I'm using, the module name is xen-pcipack, but the
sysfs directory is just pciback.  Is there an instance where the
directory is called xen-pcipack?

> >
> > Doug
> >
> > >
> > > Ian.
> > >
> > _______________________________________________
> > Xen-devel mailing list
> > Xen-devel@lists.xensource.com
> > http://lists.xensource.com/xen-devel

Re: [PATCH] libxl_pci: check that host device is assignable before adding to the domain

[Konrad Rzeszutek Wilk]

On Tue, Jan 17, 2012 at 05:02:08PM -0500, djmagee@mageenet.net wrote:
> > -----Original Message-----
> > From: Konrad Rzeszutek Wilk [mailto:konrad@darnok.org]
> > Sent: Tuesday, January 17, 2012 3:13 PM
> > To: djmagee@mageenet.net
> > Cc: Ian Campbell; xen-devel@lists.xensource.com; Ian Jackson; Stefano
> > Stabellini
> > Subject: Re: [Xen-devel] [PATCH] libxl_pci: check that host device is
> > assignable before adding to the domain
> > 
> > On Tue, Jan 17, 2012 at 09:24:39AM -0500, djmagee@mageenet.net wrote:
> > > > -----Original Message-----
> > > > From: Ian Campbell [mailto:Ian.Campbell@citrix.com]
> > > > Sent: Tuesday, January 17, 2012 9:16 AM
> > > > To: djmagee@mageenet.net
> > > > Cc: xen-devel@lists.xensource.com; Ian Jackson; Stefano Stabellini
> > > > Subject: RE: [Xen-devel] [PATCH] libxl_pci: check that host device
> > is
> > > > assignable before adding to the domain
> > > >
> > > > Please don't top post.
> > > >
> > > > On Tue, 2012-01-17 at 14:05 +0000, djmagee@mageenet.net wrote:
> > > > > That was my first thought, but this was also the first thing in
> > libxl
> > > > > I touched and wasn't sure what would happen if I ended up
> nesting
> > > > > GC_INITs.  If it's safe to do then I can call
> > > > > libxl_device_pci_list_assignable, otherwise I'd have to pull the
> > meat
> > > > > out and put it in another function.  What's the best way to do
> > it?
> > > >
> > > > You can use libxl__gc_owner(gc) (or the helpful CTX macro) to get
> a
> > ctx
> > > > from a gc which you use to call an externally visible function
> from
> > > > within libxl -- it'll do the right thing (TM).
> > >
> > > Cool, I'll send an updated patch along today.
> > 
> > You might want to check for 'xen-pciback', 'pciback' and 'pci-stub'
> > as they are valid.
> 
> Agreed. I posted an updated patch that calls ..._list_assignable instead
> of looping through the directory itself.  I'll work on a separate patch
> to update that function to check all applicable places.
> 
> In the 3.2.1 kernel I'm using, the module name is xen-pcipack, but the
> sysfs directory is just pciback.  Is there an instance where the
> directory is called xen-pcipack?

Not yet. I was hoping that somebody would create a patch in the
toolstack for it so that I can rename it to 'xen-pciback'.

So more of the 'this will happen in Q2 2012'