To determine whether a device node is a drm device node or not, the code currently compares the node's major number to the static drm major device number.
This breaks the standalone vmwgfx driver on XWayland dri clients, https://cgit.freedesktop.org/mesa/vmwgfx and any future attempt to introduce dynamic device numbers for drm.
So instead of checking for the device major, instead check for the presence of the /sys/dev/char/<major>:<minor>/device/drm directory.
Signed-off-by: Thomas Hellstrom thellstrom@vmware.com --- xf86drm.c | 31 +++++++++++++++++++++++-------- 1 file changed, 23 insertions(+), 8 deletions(-)
diff --git a/xf86drm.c b/xf86drm.c index 7807dce9..4cfc5d3e 100644 --- a/xf86drm.c +++ b/xf86drm.c @@ -2761,6 +2761,21 @@ char *drmGetDeviceNameFromFd(int fd) return strdup(name); }
+static bool +drmNodeIsDRM(int maj, int min) +{ +#ifdef __linux__ + char path[64]; + struct stat sbuf; + + snprintf(path, sizeof(path), "/sys/dev/char/%d:%d/device/drm", + maj, min); + return stat(path, &sbuf) == 0; +#else + return maj == DRM_MAJOR; +#endif +} + int drmGetNodeTypeFromFd(int fd) { struct stat sbuf; @@ -2772,7 +2787,7 @@ int drmGetNodeTypeFromFd(int fd) maj = major(sbuf.st_rdev); min = minor(sbuf.st_rdev);
- if (maj != DRM_MAJOR || !S_ISCHR(sbuf.st_mode)) { + if (!drmNodeIsDRM(maj, min) || !S_ISCHR(sbuf.st_mode)) { errno = EINVAL; return -1; } @@ -2837,7 +2852,7 @@ static char *drmGetMinorNameForFD(int fd, int type) maj = major(sbuf.st_rdev); min = minor(sbuf.st_rdev);
- if (maj != DRM_MAJOR || !S_ISCHR(sbuf.st_mode)) + if (!drmNodeIsDRM(maj, min) || !S_ISCHR(sbuf.st_mode)) return NULL;
snprintf(buf, sizeof(buf), "/sys/dev/char/%d:%d/device/drm", maj, min); @@ -2871,7 +2886,7 @@ static char *drmGetMinorNameForFD(int fd, int type) maj = major(sbuf.st_rdev); min = minor(sbuf.st_rdev);
- if (maj != DRM_MAJOR || !S_ISCHR(sbuf.st_mode)) + if (!drmNodeIsDRM(maj, min) || !S_ISCHR(sbuf.st_mode)) return NULL;
switch (type) { @@ -3731,7 +3746,7 @@ process_device(drmDevicePtr *device, const char *d_name, maj = major(sbuf.st_rdev); min = minor(sbuf.st_rdev);
- if (maj != DRM_MAJOR || !S_ISCHR(sbuf.st_mode)) + if (!drmNodeIsDRM(maj, min) || !S_ISCHR(sbuf.st_mode)) return -1;
subsystem_type = drmParseSubsystemType(maj, min); @@ -3845,7 +3860,7 @@ int drmGetDevice2(int fd, uint32_t flags, drmDevicePtr *device) maj = major(sbuf.st_rdev); min = minor(sbuf.st_rdev);
- if (maj != DRM_MAJOR || !S_ISCHR(sbuf.st_mode)) + if (!drmNodeIsDRM(maj, min) || !S_ISCHR(sbuf.st_mode)) return -EINVAL;
node_type = drmGetMinorType(min); @@ -3911,7 +3926,7 @@ int drmGetDevice2(int fd, uint32_t flags, drmDevicePtr *device) maj = major(sbuf.st_rdev); min = minor(sbuf.st_rdev);
- if (maj != DRM_MAJOR || !S_ISCHR(sbuf.st_mode)) + if (!drmNodeIsDRM(maj, min) || !S_ISCHR(sbuf.st_mode)) return -EINVAL;
subsystem_type = drmParseSubsystemType(maj, min); @@ -4071,7 +4086,7 @@ char *drmGetDeviceNameFromFd2(int fd) maj = major(sbuf.st_rdev); min = minor(sbuf.st_rdev);
- if (maj != DRM_MAJOR || !S_ISCHR(sbuf.st_mode)) + if (!drmNodeIsDRM(maj, min) || !S_ISCHR(sbuf.st_mode)) return NULL;
snprintf(path, sizeof(path), "/sys/dev/char/%d:%d", maj, min); @@ -4097,7 +4112,7 @@ char *drmGetDeviceNameFromFd2(int fd) maj = major(sbuf.st_rdev); min = minor(sbuf.st_rdev);
- if (maj != DRM_MAJOR || !S_ISCHR(sbuf.st_mode)) + if (!drmNodeIsDRM(maj, min) || !S_ISCHR(sbuf.st_mode)) return NULL;
node_type = drmGetMinorType(min);
On Friday, 2018-08-31 13:54:19 +0200, Thomas Hellstrom wrote:
To determine whether a device node is a drm device node or not, the code currently compares the node's major number to the static drm major device number.
This breaks the standalone vmwgfx driver on XWayland dri clients, https://cgit.freedesktop.org/mesa/vmwgfx and any future attempt to introduce dynamic device numbers for drm.
So instead of checking for the device major, instead check for the presence of the /sys/dev/char/<major>:<minor>/device/drm directory.
Just FYI, this means it now matches /dev/fb0 too.
I don't think this will be an issue, but just pointing it out so people notice.
Signed-off-by: Thomas Hellstrom thellstrom@vmware.com
xf86drm.c | 31 +++++++++++++++++++++++-------- 1 file changed, 23 insertions(+), 8 deletions(-)
diff --git a/xf86drm.c b/xf86drm.c index 7807dce9..4cfc5d3e 100644 --- a/xf86drm.c +++ b/xf86drm.c @@ -2761,6 +2761,21 @@ char *drmGetDeviceNameFromFd(int fd) return strdup(name); }
+static bool +drmNodeIsDRM(int maj, int min) +{ +#ifdef __linux__
- char path[64];
- struct stat sbuf;
- snprintf(path, sizeof(path), "/sys/dev/char/%d:%d/device/drm",
maj, min);
Nit: mixing tabs and space on this line.
With that fixed: Reviewed-by: Eric Engestrom eric.engestrom@intel.com
- return stat(path, &sbuf) == 0;
+#else
- return maj == DRM_MAJOR;
+#endif +}
int drmGetNodeTypeFromFd(int fd) { struct stat sbuf; @@ -2772,7 +2787,7 @@ int drmGetNodeTypeFromFd(int fd) maj = major(sbuf.st_rdev); min = minor(sbuf.st_rdev);
- if (maj != DRM_MAJOR || !S_ISCHR(sbuf.st_mode)) {
- if (!drmNodeIsDRM(maj, min) || !S_ISCHR(sbuf.st_mode)) { errno = EINVAL; return -1; }
@@ -2837,7 +2852,7 @@ static char *drmGetMinorNameForFD(int fd, int type) maj = major(sbuf.st_rdev); min = minor(sbuf.st_rdev);
- if (maj != DRM_MAJOR || !S_ISCHR(sbuf.st_mode))
if (!drmNodeIsDRM(maj, min) || !S_ISCHR(sbuf.st_mode)) return NULL;
snprintf(buf, sizeof(buf), "/sys/dev/char/%d:%d/device/drm", maj, min);
@@ -2871,7 +2886,7 @@ static char *drmGetMinorNameForFD(int fd, int type) maj = major(sbuf.st_rdev); min = minor(sbuf.st_rdev);
- if (maj != DRM_MAJOR || !S_ISCHR(sbuf.st_mode))
if (!drmNodeIsDRM(maj, min) || !S_ISCHR(sbuf.st_mode)) return NULL;
switch (type) {
@@ -3731,7 +3746,7 @@ process_device(drmDevicePtr *device, const char *d_name, maj = major(sbuf.st_rdev); min = minor(sbuf.st_rdev);
- if (maj != DRM_MAJOR || !S_ISCHR(sbuf.st_mode))
if (!drmNodeIsDRM(maj, min) || !S_ISCHR(sbuf.st_mode)) return -1;
subsystem_type = drmParseSubsystemType(maj, min);
@@ -3845,7 +3860,7 @@ int drmGetDevice2(int fd, uint32_t flags, drmDevicePtr *device) maj = major(sbuf.st_rdev); min = minor(sbuf.st_rdev);
- if (maj != DRM_MAJOR || !S_ISCHR(sbuf.st_mode))
if (!drmNodeIsDRM(maj, min) || !S_ISCHR(sbuf.st_mode)) return -EINVAL;
node_type = drmGetMinorType(min);
@@ -3911,7 +3926,7 @@ int drmGetDevice2(int fd, uint32_t flags, drmDevicePtr *device) maj = major(sbuf.st_rdev); min = minor(sbuf.st_rdev);
- if (maj != DRM_MAJOR || !S_ISCHR(sbuf.st_mode))
if (!drmNodeIsDRM(maj, min) || !S_ISCHR(sbuf.st_mode)) return -EINVAL;
subsystem_type = drmParseSubsystemType(maj, min);
@@ -4071,7 +4086,7 @@ char *drmGetDeviceNameFromFd2(int fd) maj = major(sbuf.st_rdev); min = minor(sbuf.st_rdev);
- if (maj != DRM_MAJOR || !S_ISCHR(sbuf.st_mode))
if (!drmNodeIsDRM(maj, min) || !S_ISCHR(sbuf.st_mode)) return NULL;
snprintf(path, sizeof(path), "/sys/dev/char/%d:%d", maj, min);
@@ -4097,7 +4112,7 @@ char *drmGetDeviceNameFromFd2(int fd) maj = major(sbuf.st_rdev); min = minor(sbuf.st_rdev);
- if (maj != DRM_MAJOR || !S_ISCHR(sbuf.st_mode))
if (!drmNodeIsDRM(maj, min) || !S_ISCHR(sbuf.st_mode)) return NULL;
node_type = drmGetMinorType(min);
-- 2.18.0.rc1
dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel
Hi Thomas,
On 31 August 2018 at 12:54, Thomas Hellstrom thellstrom@vmware.com wrote:
To determine whether a device node is a drm device node or not, the code currently compares the node's major number to the static drm major device number.
This breaks the standalone vmwgfx driver on XWayland dri clients, https://cgit.freedesktop.org/mesa/vmwgfx
Any particular reason why the code doesn't use a fixed node there? It will make the diff vs the in-kernel driver a bit smaller.
and any future attempt to introduce dynamic device numbers for drm.
I'm not sure how well any such attempt will pan out, regardless of the libdrm checks.
Namely: the static 226 has been used by a number of tools that interpose the libc' ioctl function. There could be others that also depend on it.
Personally, I'd go with the kernel developers decision.
Dave, Daniel, others Should we keep or drop the major == 226 checks.
Thanks Emil
Hi, Emil On 08/31/2018 02:30 PM, Emil Velikov wrote:
Hi Thomas,
On 31 August 2018 at 12:54, Thomas Hellstrom thellstrom@vmware.com wrote:
To determine whether a device node is a drm device node or not, the code currently compares the node's major number to the static drm major device number.
This breaks the standalone vmwgfx driver on XWayland dri clients,
Any particular reason why the code doesn't use a fixed node there? It will make the diff vs the in-kernel driver a bit smaller.
Because then it won't be able to interoperate with other in-tree drivers, like virtual drm drivers or passthrough usb drm drivers. There is no clean way to share the minor number allocation with in-tree drm, so standalone vmwgfx is using dynamic major allocation.
and any future attempt to introduce dynamic device numbers for drm.
I'm not sure how well any such attempt will pan out, regardless of the libdrm checks.
Namely: the static 226 has been used by a number of tools that interpose the libc' ioctl function. There could be others that also depend on it.
True, in any case for existing drivers changing static 226 to something else is at least 10+ years away according to Linus' policy, so the main issue here is really to get rid of a big annoyance in the standalone vmwgfx case.
/Thomas
Personally, I'd go with the kernel developers decision.
Dave, Daniel, others Should we keep or drop the major == 226 checks.
Thanks Emil
[ Adding the amd-gfx list ]
On 2018-08-31 3:05 p.m., Thomas Hellstrom wrote:
On 08/31/2018 02:30 PM, Emil Velikov wrote:
On 31 August 2018 at 12:54, Thomas Hellstrom thellstrom@vmware.com wrote:
To determine whether a device node is a drm device node or not, the code currently compares the node's major number to the static drm major device number.
This breaks the standalone vmwgfx driver on XWayland dri clients,
Any particular reason why the code doesn't use a fixed node there? It will make the diff vs the in-kernel driver a bit smaller.
Because then it won't be able to interoperate with other in-tree drivers, like virtual drm drivers or passthrough usb drm drivers. There is no clean way to share the minor number allocation with in-tree drm, so standalone vmwgfx is using dynamic major allocation.
I wonder why I haven't heard of any of these issues with the standalone version of amdgpu shipped in packaged AMD releases. Does that also use a different major number? If yes, maybe it's just that nobody has tried Xwayland clients with that driver. If no, how does it avoid the other issues described above?
On 08/31/2018 04:38 PM, Michel Dänzer wrote:
[ Adding the amd-gfx list ]
On 2018-08-31 3:05 p.m., Thomas Hellstrom wrote:
On 08/31/2018 02:30 PM, Emil Velikov wrote:
On 31 August 2018 at 12:54, Thomas Hellstrom thellstrom@vmware.com wrote:
To determine whether a device node is a drm device node or not, the code currently compares the node's major number to the static drm major device number.
This breaks the standalone vmwgfx driver on XWayland dri clients,
Any particular reason why the code doesn't use a fixed node there? It will make the diff vs the in-kernel driver a bit smaller.
Because then it won't be able to interoperate with other in-tree drivers, like virtual drm drivers or passthrough usb drm drivers. There is no clean way to share the minor number allocation with in-tree drm, so standalone vmwgfx is using dynamic major allocation.
I wonder why I haven't heard of any of these issues with the standalone version of amdgpu shipped in packaged AMD releases. Does that also use a different major number? If yes, maybe it's just that nobody has tried Xwayland clients with that driver. If no, how does it avoid the other issues described above?
Is standalone AMD supposed to be able to coexist with in-tree drm drivers?
/Thomas
On 2018-08-31 4:46 p.m., Thomas Hellstrom wrote:
On 08/31/2018 04:38 PM, Michel Dänzer wrote:
[ Adding the amd-gfx list ]
On 2018-08-31 3:05 p.m., Thomas Hellstrom wrote:
On 08/31/2018 02:30 PM, Emil Velikov wrote:
On 31 August 2018 at 12:54, Thomas Hellstrom thellstrom@vmware.com wrote:
To determine whether a device node is a drm device node or not, the code currently compares the node's major number to the static drm major device number.
This breaks the standalone vmwgfx driver on XWayland dri clients,
Any particular reason why the code doesn't use a fixed node there? It will make the diff vs the in-kernel driver a bit smaller.
Because then it won't be able to interoperate with other in-tree drivers, like virtual drm drivers or passthrough usb drm drivers. There is no clean way to share the minor number allocation with in-tree drm, so standalone vmwgfx is using dynamic major allocation.
I wonder why I haven't heard of any of these issues with the standalone version of amdgpu shipped in packaged AMD releases. Does that also use a different major number? If yes, maybe it's just that nobody has tried Xwayland clients with that driver. If no, how does it avoid the other issues described above?
Is standalone AMD supposed to be able to coexist with in-tree drm drivers?
Yes, it does, it's working e.g. on laptops with an Intel integrated and an AMD discrete GPU.
On 08/31/2018 04:49 PM, Michel Dänzer wrote:
On 2018-08-31 4:46 p.m., Thomas Hellstrom wrote:
On 08/31/2018 04:38 PM, Michel Dänzer wrote:
[ Adding the amd-gfx list ]
On 2018-08-31 3:05 p.m., Thomas Hellstrom wrote:
On 08/31/2018 02:30 PM, Emil Velikov wrote:
On 31 August 2018 at 12:54, Thomas Hellstrom thellstrom@vmware.com wrote:
To determine whether a device node is a drm device node or not, the code currently compares the node's major number to the static drm major device number.
This breaks the standalone vmwgfx driver on XWayland dri clients,
Any particular reason why the code doesn't use a fixed node there? It will make the diff vs the in-kernel driver a bit smaller.
Because then it won't be able to interoperate with other in-tree drivers, like virtual drm drivers or passthrough usb drm drivers. There is no clean way to share the minor number allocation with in-tree drm, so standalone vmwgfx is using dynamic major allocation.
I wonder why I haven't heard of any of these issues with the standalone version of amdgpu shipped in packaged AMD releases. Does that also use a different major number? If yes, maybe it's just that nobody has tried Xwayland clients with that driver. If no, how does it avoid the other issues described above?
Is standalone AMD supposed to be able to coexist with in-tree drm drivers?
Yes, it does, it's working e.g. on laptops with an Intel integrated and an AMD discrete GPU.
Hmm. The symptoms with xf86-video-vmware are that when mesa initializes, we get: MESA-LOADER: failed to retrieve device information MESA-LOADER: failed to retrieve device information MESA-LOADER: failed to retrieve device information
but then vmwgfx_dri.so loads anyway.
With XWayland, mesa just silently tries swrast instead of vmwgfx.
Not sure this has always been the case though. It might be due to a recent XWayland change. In any case, the change to libdrm silence the warnings on Xorg and makes mesa try vmwgfx on XWayland.
/Thomas
On 31 August 2018 at 15:38, Michel Dänzer michel@daenzer.net wrote:
[ Adding the amd-gfx list ]
On 2018-08-31 3:05 p.m., Thomas Hellstrom wrote:
On 08/31/2018 02:30 PM, Emil Velikov wrote:
On 31 August 2018 at 12:54, Thomas Hellstrom thellstrom@vmware.com wrote:
To determine whether a device node is a drm device node or not, the code currently compares the node's major number to the static drm major device number.
This breaks the standalone vmwgfx driver on XWayland dri clients,
Any particular reason why the code doesn't use a fixed node there? It will make the diff vs the in-kernel driver a bit smaller.
Because then it won't be able to interoperate with other in-tree drivers, like virtual drm drivers or passthrough usb drm drivers. There is no clean way to share the minor number allocation with in-tree drm, so standalone vmwgfx is using dynamic major allocation.
I wonder why I haven't heard of any of these issues with the standalone version of amdgpu shipped in packaged AMD releases. Does that also use a different major number? If yes, maybe it's just that nobody has tried Xwayland clients with that driver. If no, how does it avoid the other issues described above?
AFAICT, the difference is that the standalone vmwgfx uses an internal copy of drm core. It doesn't reuse the in-kernel drm, hence it cannot know which minor it can use.
-Emil
On 08/31/2018 05:27 PM, Emil Velikov wrote:
On 31 August 2018 at 15:38, Michel Dänzer michel@daenzer.net wrote:
[ Adding the amd-gfx list ]
On 2018-08-31 3:05 p.m., Thomas Hellstrom wrote:
On 08/31/2018 02:30 PM, Emil Velikov wrote:
On 31 August 2018 at 12:54, Thomas Hellstrom thellstrom@vmware.com wrote:
To determine whether a device node is a drm device node or not, the code currently compares the node's major number to the static drm major device number.
This breaks the standalone vmwgfx driver on XWayland dri clients,
Any particular reason why the code doesn't use a fixed node there? It will make the diff vs the in-kernel driver a bit smaller.
Because then it won't be able to interoperate with other in-tree drivers, like virtual drm drivers or passthrough usb drm drivers. There is no clean way to share the minor number allocation with in-tree drm, so standalone vmwgfx is using dynamic major allocation.
I wonder why I haven't heard of any of these issues with the standalone version of amdgpu shipped in packaged AMD releases. Does that also use a different major number? If yes, maybe it's just that nobody has tried Xwayland clients with that driver. If no, how does it avoid the other issues described above?
AFAICT, the difference is that the standalone vmwgfx uses an internal copy of drm core. It doesn't reuse the in-kernel drm, hence it cannot know which minor it can use.
-Emil
Actually, standalone vmwgfx could perhaps also try to allocate minors from 63 and downwards. That might work, but needs some verification.
/Thomas
On 08/31/2018 05:30 PM, Thomas Hellstrom wrote:
On 08/31/2018 05:27 PM, Emil Velikov wrote:
On 31 August 2018 at 15:38, Michel Dänzer michel@daenzer.net wrote:
[ Adding the amd-gfx list ]
On 2018-08-31 3:05 p.m., Thomas Hellstrom wrote:
On 08/31/2018 02:30 PM, Emil Velikov wrote:
On 31 August 2018 at 12:54, Thomas Hellstrom thellstrom@vmware.com wrote:
To determine whether a device node is a drm device node or not, the code currently compares the node's major number to the static drm major device number.
This breaks the standalone vmwgfx driver on XWayland dri clients,
Any particular reason why the code doesn't use a fixed node there? It will make the diff vs the in-kernel driver a bit smaller.
Because then it won't be able to interoperate with other in-tree drivers, like virtual drm drivers or passthrough usb drm drivers. There is no clean way to share the minor number allocation with in-tree drm, so standalone vmwgfx is using dynamic major allocation.
I wonder why I haven't heard of any of these issues with the standalone version of amdgpu shipped in packaged AMD releases. Does that also use a different major number? If yes, maybe it's just that nobody has tried Xwayland clients with that driver. If no, how does it avoid the other issues described above?
AFAICT, the difference is that the standalone vmwgfx uses an internal copy of drm core. It doesn't reuse the in-kernel drm, hence it cannot know which minor it can use.
-Emil
Actually, standalone vmwgfx could perhaps also try to allocate minors from 63 and downwards. That might work, but needs some verification.
So unfortuntately this doesn't work since the in-tree drm's file operations are registered with the DRM_MAJOR. So I still think the patch is the way to go. If people are concerned that also fbdev file descriptors are allowed, perhaps there are other sysfs traits we can look at?
/Thomas
/Thomas
On Mon, Sep 03, 2018 at 11:16:29AM +0200, Thomas Hellstrom wrote:
On 08/31/2018 05:30 PM, Thomas Hellstrom wrote:
On 08/31/2018 05:27 PM, Emil Velikov wrote:
On 31 August 2018 at 15:38, Michel Dänzer michel@daenzer.net wrote:
[ Adding the amd-gfx list ]
On 2018-08-31 3:05 p.m., Thomas Hellstrom wrote:
On 08/31/2018 02:30 PM, Emil Velikov wrote:
On 31 August 2018 at 12:54, Thomas Hellstrom thellstrom@vmware.com wrote: > To determine whether a device node is a drm device > node or not, the code > currently compares the node's major number to the static drm major > device > number. > > This breaks the standalone vmwgfx driver on XWayland dri clients, > Any particular reason why the code doesn't use a fixed node there? It will make the diff vs the in-kernel driver a bit smaller.
Because then it won't be able to interoperate with other in-tree drivers, like virtual drm drivers or passthrough usb drm drivers. There is no clean way to share the minor number allocation with in-tree drm, so standalone vmwgfx is using dynamic major allocation.
I wonder why I haven't heard of any of these issues with the standalone version of amdgpu shipped in packaged AMD releases. Does that also use a different major number? If yes, maybe it's just that nobody has tried Xwayland clients with that driver. If no, how does it avoid the other issues described above?
AFAICT, the difference is that the standalone vmwgfx uses an internal copy of drm core. It doesn't reuse the in-kernel drm, hence it cannot know which minor it can use.
-Emil
Actually, standalone vmwgfx could perhaps also try to allocate minors from 63 and downwards. That might work, but needs some verification.
So unfortuntately this doesn't work since the in-tree drm's file operations are registered with the DRM_MAJOR. So I still think the patch is the way to go. If people are concerned that also fbdev file descriptors are allowed, perhaps there are other sysfs traits we can look at?
Somewhat out of curiosity, but why do you have to overwrite all of drm? amdgpu seems to be able to pull their stunt off without ... -Daniel
On 09/03/2018 06:33 PM, Daniel Vetter wrote:
On Mon, Sep 03, 2018 at 11:16:29AM +0200, Thomas Hellstrom wrote:
On 08/31/2018 05:30 PM, Thomas Hellstrom wrote:
On 08/31/2018 05:27 PM, Emil Velikov wrote:
On 31 August 2018 at 15:38, Michel Dänzer michel@daenzer.net wrote:
[ Adding the amd-gfx list ]
On 2018-08-31 3:05 p.m., Thomas Hellstrom wrote:
On 08/31/2018 02:30 PM, Emil Velikov wrote: > On 31 August 2018 at 12:54, Thomas Hellstrom thellstrom@vmware.com > wrote: >> To determine whether a device node is a drm device >> node or not, the code >> currently compares the node's major number to the static drm major >> device >> number. >> >> This breaks the standalone vmwgfx driver on XWayland dri clients, >> > Any particular reason why the code doesn't use a fixed node there? > It will make the diff vs the in-kernel driver a bit smaller. Because then it won't be able to interoperate with other in-tree drivers, like virtual drm drivers or passthrough usb drm drivers. There is no clean way to share the minor number allocation with in-tree drm, so standalone vmwgfx is using dynamic major allocation.
I wonder why I haven't heard of any of these issues with the standalone version of amdgpu shipped in packaged AMD releases. Does that also use a different major number? If yes, maybe it's just that nobody has tried Xwayland clients with that driver. If no, how does it avoid the other issues described above?
AFAICT, the difference is that the standalone vmwgfx uses an internal copy of drm core. It doesn't reuse the in-kernel drm, hence it cannot know which minor it can use.
-Emil
Actually, standalone vmwgfx could perhaps also try to allocate minors from 63 and downwards. That might work, but needs some verification.
So unfortuntately this doesn't work since the in-tree drm's file operations are registered with the DRM_MAJOR. So I still think the patch is the way to go. If people are concerned that also fbdev file descriptors are allowed, perhaps there are other sysfs traits we can look at?
Somewhat out of curiosity, but why do you have to overwrite all of drm? amdgpu seems to be able to pull their stunt off without ... -Daniel
At the time we launched the standalone vmwgfx, the DRM <-> driver interface was moving considerably more rapidly than the DRM <-> kernel interface. I think that's still the case. Hence less work for us. Also meant we can install the full driver stack with latest features on fairly old VMs without backported DRM functionality.
/Thomas
On Tue, 4 Sep 2018 at 03:00, Thomas Hellstrom thellstrom@vmware.com wrote:
On 09/03/2018 06:33 PM, Daniel Vetter wrote:
On Mon, Sep 03, 2018 at 11:16:29AM +0200, Thomas Hellstrom wrote:
On 08/31/2018 05:30 PM, Thomas Hellstrom wrote:
On 08/31/2018 05:27 PM, Emil Velikov wrote:
On 31 August 2018 at 15:38, Michel Dänzer michel@daenzer.net wrote:
[ Adding the amd-gfx list ]
On 2018-08-31 3:05 p.m., Thomas Hellstrom wrote: > On 08/31/2018 02:30 PM, Emil Velikov wrote: >> On 31 August 2018 at 12:54, Thomas Hellstrom thellstrom@vmware.com >> wrote: >>> To determine whether a device node is a drm device >>> node or not, the code >>> currently compares the node's major number to the static drm major >>> device >>> number. >>> >>> This breaks the standalone vmwgfx driver on XWayland dri clients, >>> >> Any particular reason why the code doesn't use a fixed node there? >> It will make the diff vs the in-kernel driver a bit smaller. > Because then it won't be able to interoperate with other in-tree > drivers, like virtual drm drivers or passthrough usb drm drivers. > There is no clean way to share the minor number allocation > with in-tree > drm, so standalone vmwgfx is using dynamic major allocation. I wonder why I haven't heard of any of these issues with the standalone version of amdgpu shipped in packaged AMD releases. Does that also use a different major number? If yes, maybe it's just that nobody has tried Xwayland clients with that driver. If no, how does it avoid the other issues described above?
AFAICT, the difference is that the standalone vmwgfx uses an internal copy of drm core. It doesn't reuse the in-kernel drm, hence it cannot know which minor it can use.
-Emil
Actually, standalone vmwgfx could perhaps also try to allocate minors from 63 and downwards. That might work, but needs some verification.
So unfortuntately this doesn't work since the in-tree drm's file operations are registered with the DRM_MAJOR. So I still think the patch is the way to go. If people are concerned that also fbdev file descriptors are allowed, perhaps there are other sysfs traits we can look at?
Somewhat out of curiosity, but why do you have to overwrite all of drm? amdgpu seems to be able to pull their stunt off without ... -Daniel
At the time we launched the standalone vmwgfx, the DRM <-> driver interface was moving considerably more rapidly than the DRM <-> kernel interface. I think that's still the case. Hence less work for us. Also meant we can install the full driver stack with latest features on fairly old VMs without backported DRM functionality.
I think this should be fine for 99% of drm usage, there may be corner cases in wierd places, but I can't point to any that really matter (maybe strace?)
Acked-by: Dave Airlie airlied@redhat.com
Dave.
On 4 September 2018 at 23:33, Dave Airlie airlied@gmail.com wrote:
On Tue, 4 Sep 2018 at 03:00, Thomas Hellstrom thellstrom@vmware.com wrote:
On 09/03/2018 06:33 PM, Daniel Vetter wrote:
On Mon, Sep 03, 2018 at 11:16:29AM +0200, Thomas Hellstrom wrote:
On 08/31/2018 05:30 PM, Thomas Hellstrom wrote:
On 08/31/2018 05:27 PM, Emil Velikov wrote:
On 31 August 2018 at 15:38, Michel Dänzer michel@daenzer.net wrote: > [ Adding the amd-gfx list ] > > On 2018-08-31 3:05 p.m., Thomas Hellstrom wrote: >> On 08/31/2018 02:30 PM, Emil Velikov wrote: >>> On 31 August 2018 at 12:54, Thomas Hellstrom thellstrom@vmware.com >>> wrote: >>>> To determine whether a device node is a drm device >>>> node or not, the code >>>> currently compares the node's major number to the static drm major >>>> device >>>> number. >>>> >>>> This breaks the standalone vmwgfx driver on XWayland dri clients, >>>> >>> Any particular reason why the code doesn't use a fixed node there? >>> It will make the diff vs the in-kernel driver a bit smaller. >> Because then it won't be able to interoperate with other in-tree >> drivers, like virtual drm drivers or passthrough usb drm drivers. >> There is no clean way to share the minor number allocation >> with in-tree >> drm, so standalone vmwgfx is using dynamic major allocation. > I wonder why I haven't heard of any of these issues with the standalone > version of amdgpu shipped in packaged AMD releases. Does that > also use a > different major number? If yes, maybe it's just that nobody has tried > Xwayland clients with that driver. If no, how does it avoid the other > issues described above? > AFAICT, the difference is that the standalone vmwgfx uses an internal copy of drm core. It doesn't reuse the in-kernel drm, hence it cannot know which minor it can use.
-Emil
Actually, standalone vmwgfx could perhaps also try to allocate minors from 63 and downwards. That might work, but needs some verification.
So unfortuntately this doesn't work since the in-tree drm's file operations are registered with the DRM_MAJOR. So I still think the patch is the way to go. If people are concerned that also fbdev file descriptors are allowed, perhaps there are other sysfs traits we can look at?
Somewhat out of curiosity, but why do you have to overwrite all of drm? amdgpu seems to be able to pull their stunt off without ... -Daniel
At the time we launched the standalone vmwgfx, the DRM <-> driver interface was moving considerably more rapidly than the DRM <-> kernel interface. I think that's still the case. Hence less work for us. Also meant we can install the full driver stack with latest features on fairly old VMs without backported DRM functionality.
I think this should be fine for 99% of drm usage, there may be corner cases in wierd places, but I can't point to any that really matter (maybe strace?)
Having a closer look, I think this will break the Firefox/Chrome sandboxing :-\ I cannot see the path /sys/dev/char/%d:%d/device/drm in the allowed list [1] [2].
Thomas, can you please send a patch to the respective teams or give them a heads up?
Thanks Emil
[1] https://hg.mozilla.org/releases/mozilla-beta/file/264fcd3206a6/security/sand... [2] https://chromium.googlesource.com/chromium/src/+/8655d49f657d3878c937f1387b3...
Hi, Emil,
On 09/05/2018 11:33 AM, Emil Velikov wrote:
On 4 September 2018 at 23:33, Dave Airlie airlied@gmail.com wrote:
On Tue, 4 Sep 2018 at 03:00, Thomas Hellstrom thellstrom@vmware.com wrote:
On 09/03/2018 06:33 PM, Daniel Vetter wrote:
On Mon, Sep 03, 2018 at 11:16:29AM +0200, Thomas Hellstrom wrote:
On 08/31/2018 05:30 PM, Thomas Hellstrom wrote:
On 08/31/2018 05:27 PM, Emil Velikov wrote: > On 31 August 2018 at 15:38, Michel Dänzer michel@daenzer.net wrote: >> [ Adding the amd-gfx list ] >> >> On 2018-08-31 3:05 p.m., Thomas Hellstrom wrote: >>> On 08/31/2018 02:30 PM, Emil Velikov wrote: >>>> On 31 August 2018 at 12:54, Thomas Hellstrom thellstrom@vmware.com >>>> wrote: >>>>> To determine whether a device node is a drm device >>>>> node or not, the code >>>>> currently compares the node's major number to the static drm major >>>>> device >>>>> number. >>>>> >>>>> This breaks the standalone vmwgfx driver on XWayland dri clients, >>>>> >>>> Any particular reason why the code doesn't use a fixed node there? >>>> It will make the diff vs the in-kernel driver a bit smaller. >>> Because then it won't be able to interoperate with other in-tree >>> drivers, like virtual drm drivers or passthrough usb drm drivers. >>> There is no clean way to share the minor number allocation >>> with in-tree >>> drm, so standalone vmwgfx is using dynamic major allocation. >> I wonder why I haven't heard of any of these issues with the standalone >> version of amdgpu shipped in packaged AMD releases. Does that >> also use a >> different major number? If yes, maybe it's just that nobody has tried >> Xwayland clients with that driver. If no, how does it avoid the other >> issues described above? >> > AFAICT, the difference is that the standalone vmwgfx uses an internal > copy of drm core. > It doesn't reuse the in-kernel drm, hence it cannot know which minor > it can use. > > -Emil Actually, standalone vmwgfx could perhaps also try to allocate minors from 63 and downwards. That might work, but needs some verification.
So unfortuntately this doesn't work since the in-tree drm's file operations are registered with the DRM_MAJOR. So I still think the patch is the way to go. If people are concerned that also fbdev file descriptors are allowed, perhaps there are other sysfs traits we can look at?
Somewhat out of curiosity, but why do you have to overwrite all of drm? amdgpu seems to be able to pull their stunt off without ... -Daniel
At the time we launched the standalone vmwgfx, the DRM <-> driver interface was moving considerably more rapidly than the DRM <-> kernel interface. I think that's still the case. Hence less work for us. Also meant we can install the full driver stack with latest features on fairly old VMs without backported DRM functionality.
I think this should be fine for 99% of drm usage, there may be corner cases in wierd places, but I can't point to any that really matter (maybe strace?)
Having a closer look, I think this will break the Firefox/Chrome sandboxing :-\ I cannot see the path /sys/dev/char/%d:%d/device/drm in the allowed list [1] [2].
Thanks for pointing this out.
The function drmGetMinorNameForFD() already opens this path, so any user-space using that function would not work before either.
Also mozilla/firefox adds /sys/dev/char/226:* Which means that while it still won't work on standalone vmwgfx, there should at least be no regression.
For Chromium it seems they allow /sys/dev/char/ for AmdGpu, but only under ChromOS, so I'll ping those to be safe.
I also won't be doing an immediate release after pushing.
Thanks, Thomas
Thomas, can you please send a patch to the respective teams or give them a heads up?
Thanks Emil
On 5 September 2018 at 11:10, Thomas Hellstrom thellstrom@vmware.com wrote:
Hi, Emil,
On 09/05/2018 11:33 AM, Emil Velikov wrote:
On 4 September 2018 at 23:33, Dave Airlie airlied@gmail.com wrote:
On Tue, 4 Sep 2018 at 03:00, Thomas Hellstrom thellstrom@vmware.com wrote:
On 09/03/2018 06:33 PM, Daniel Vetter wrote:
On Mon, Sep 03, 2018 at 11:16:29AM +0200, Thomas Hellstrom wrote:
On 08/31/2018 05:30 PM, Thomas Hellstrom wrote: > > On 08/31/2018 05:27 PM, Emil Velikov wrote: >> >> On 31 August 2018 at 15:38, Michel Dänzer michel@daenzer.net >> wrote: >>> >>> [ Adding the amd-gfx list ] >>> >>> On 2018-08-31 3:05 p.m., Thomas Hellstrom wrote: >>>> >>>> On 08/31/2018 02:30 PM, Emil Velikov wrote: >>>>> >>>>> On 31 August 2018 at 12:54, Thomas Hellstrom >>>>> thellstrom@vmware.com >>>>> wrote: >>>>>> >>>>>> To determine whether a device node is a drm device >>>>>> node or not, the code >>>>>> currently compares the node's major number to the static drm >>>>>> major >>>>>> device >>>>>> number. >>>>>> >>>>>> This breaks the standalone vmwgfx driver on XWayland dri >>>>>> clients, >>>>>> >>>>> Any particular reason why the code doesn't use a fixed node >>>>> there? >>>>> It will make the diff vs the in-kernel driver a bit smaller. >>>> >>>> Because then it won't be able to interoperate with other in-tree >>>> drivers, like virtual drm drivers or passthrough usb drm drivers. >>>> There is no clean way to share the minor number allocation >>>> with in-tree >>>> drm, so standalone vmwgfx is using dynamic major allocation. >>> >>> I wonder why I haven't heard of any of these issues with the >>> standalone >>> version of amdgpu shipped in packaged AMD releases. Does that >>> also use a >>> different major number? If yes, maybe it's just that nobody has >>> tried >>> Xwayland clients with that driver. If no, how does it avoid the >>> other >>> issues described above? >>> >> AFAICT, the difference is that the standalone vmwgfx uses an >> internal >> copy of drm core. >> It doesn't reuse the in-kernel drm, hence it cannot know which minor >> it can use. >> >> -Emil > > Actually, standalone vmwgfx could perhaps also try to allocate minors > from 63 and downwards. That might work, but needs some verification. > So unfortuntately this doesn't work since the in-tree drm's file operations are registered with the DRM_MAJOR. So I still think the patch is the way to go. If people are concerned that also fbdev file descriptors are allowed, perhaps there are other sysfs traits we can look at?
Somewhat out of curiosity, but why do you have to overwrite all of drm? amdgpu seems to be able to pull their stunt off without ... -Daniel
At the time we launched the standalone vmwgfx, the DRM <-> driver interface was moving considerably more rapidly than the DRM <-> kernel interface. I think that's still the case. Hence less work for us. Also meant we can install the full driver stack with latest features on fairly old VMs without backported DRM functionality.
I think this should be fine for 99% of drm usage, there may be corner cases in wierd places, but I can't point to any that really matter (maybe strace?)
Having a closer look, I think this will break the Firefox/Chrome sandboxing :-\ I cannot see the path /sys/dev/char/%d:%d/device/drm in the allowed list [1] [2].
Thanks for pointing this out.
The function drmGetMinorNameForFD() already opens this path, so any user-space using that function would not work before either.
Also mozilla/firefox adds /sys/dev/char/226:* Which means that while it still won't work on standalone vmwgfx, there should at least be no regression.
For Chromium it seems they allow /sys/dev/char/ for AmdGpu, but only under ChromOS, so I'll ping those to be safe.
I also won't be doing an immediate release after pushing.
In that case, please give me 24h to do a libdrm release before pushing. I had to push some workarounds for the sandboxing mentioned earlier :-\
Thanks Emil
On 09/05/2018 03:07 PM, Emil Velikov wrote:
On 5 September 2018 at 11:10, Thomas Hellstrom thellstrom@vmware.com wrote:
Hi, Emil,
On 09/05/2018 11:33 AM, Emil Velikov wrote:
On 4 September 2018 at 23:33, Dave Airlie airlied@gmail.com wrote:
On Tue, 4 Sep 2018 at 03:00, Thomas Hellstrom thellstrom@vmware.com wrote:
On 09/03/2018 06:33 PM, Daniel Vetter wrote:
On Mon, Sep 03, 2018 at 11:16:29AM +0200, Thomas Hellstrom wrote: > On 08/31/2018 05:30 PM, Thomas Hellstrom wrote: >> On 08/31/2018 05:27 PM, Emil Velikov wrote: >>> On 31 August 2018 at 15:38, Michel Dänzer michel@daenzer.net >>> wrote: >>>> [ Adding the amd-gfx list ] >>>> >>>> On 2018-08-31 3:05 p.m., Thomas Hellstrom wrote: >>>>> On 08/31/2018 02:30 PM, Emil Velikov wrote: >>>>>> On 31 August 2018 at 12:54, Thomas Hellstrom >>>>>> thellstrom@vmware.com >>>>>> wrote: >>>>>>> To determine whether a device node is a drm device >>>>>>> node or not, the code >>>>>>> currently compares the node's major number to the static drm >>>>>>> major >>>>>>> device >>>>>>> number. >>>>>>> >>>>>>> This breaks the standalone vmwgfx driver on XWayland dri >>>>>>> clients, >>>>>>> >>>>>> Any particular reason why the code doesn't use a fixed node >>>>>> there? >>>>>> It will make the diff vs the in-kernel driver a bit smaller. >>>>> Because then it won't be able to interoperate with other in-tree >>>>> drivers, like virtual drm drivers or passthrough usb drm drivers. >>>>> There is no clean way to share the minor number allocation >>>>> with in-tree >>>>> drm, so standalone vmwgfx is using dynamic major allocation. >>>> I wonder why I haven't heard of any of these issues with the >>>> standalone >>>> version of amdgpu shipped in packaged AMD releases. Does that >>>> also use a >>>> different major number? If yes, maybe it's just that nobody has >>>> tried >>>> Xwayland clients with that driver. If no, how does it avoid the >>>> other >>>> issues described above? >>>> >>> AFAICT, the difference is that the standalone vmwgfx uses an >>> internal >>> copy of drm core. >>> It doesn't reuse the in-kernel drm, hence it cannot know which minor >>> it can use. >>> >>> -Emil >> Actually, standalone vmwgfx could perhaps also try to allocate minors >> from 63 and downwards. That might work, but needs some verification. >> > So unfortuntately this doesn't work since the in-tree drm's file > operations > are registered with the DRM_MAJOR. > So I still think the patch is the way to go. If people are concerned > that > also fbdev file descriptors are allowed, perhaps there are other sysfs > traits we can look at? Somewhat out of curiosity, but why do you have to overwrite all of drm? amdgpu seems to be able to pull their stunt off without ... -Daniel
At the time we launched the standalone vmwgfx, the DRM <-> driver interface was moving considerably more rapidly than the DRM <-> kernel interface. I think that's still the case. Hence less work for us. Also meant we can install the full driver stack with latest features on fairly old VMs without backported DRM functionality.
I think this should be fine for 99% of drm usage, there may be corner cases in wierd places, but I can't point to any that really matter (maybe strace?)
Having a closer look, I think this will break the Firefox/Chrome sandboxing :-\ I cannot see the path /sys/dev/char/%d:%d/device/drm in the allowed list [1] [2].
Thanks for pointing this out.
The function drmGetMinorNameForFD() already opens this path, so any user-space using that function would not work before either.
Also mozilla/firefox adds /sys/dev/char/226:* Which means that while it still won't work on standalone vmwgfx, there should at least be no regression.
For Chromium it seems they allow /sys/dev/char/ for AmdGpu, but only under ChromOS, so I'll ping those to be safe.
I also won't be doing an immediate release after pushing.
In that case, please give me 24h to do a libdrm release before pushing. I had to push some workarounds for the sandboxing mentioned earlier :-\
Thanks Emil
Ouch, I just pushed the patch, but feel free to cut the release just before that commit.
/Thomas
On 5 September 2018 at 14:20, Thomas Hellstrom thellstrom@vmware.com wrote:
In that case, please give me 24h to do a libdrm release before pushing. I had to push some workarounds for the sandboxing mentioned earlier :-\
Thanks Emil
Ouch, I just pushed the patch, but feel free to cut the release just before that commit.
That doesn't quite work. Barring any objections I'll: revert, release, reapply.
-Emil
Hi, Emil,
On 09/05/2018 03:53 PM, Emil Velikov wrote:
On 5 September 2018 at 14:20, Thomas Hellstrom thellstrom@vmware.com wrote:
In that case, please give me 24h to do a libdrm release before pushing. I had to push some workarounds for the sandboxing mentioned earlier :-\
Thanks Emil
Ouch, I just pushed the patch, but feel free to cut the release just before that commit.
That doesn't quite work. Barring any objections I'll: revert, release, reapply.
-Emil _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel
What happened here? I can't really see my commit nor a revert nor a release in libdrm.
/Thomas
Ping?
On 09/30/2018 07:31 PM, Thomas Hellstrom wrote:
Hi, Emil,
On 09/05/2018 03:53 PM, Emil Velikov wrote:
On 5 September 2018 at 14:20, Thomas Hellstrom thellstrom@vmware.com wrote:
In that case, please give me 24h to do a libdrm release before pushing. I had to push some workarounds for the sandboxing mentioned earlier :-\
Thanks Emil
Ouch, I just pushed the patch, but feel free to cut the release just before that commit.
That doesn't quite work. Barring any objections I'll: revert, release, reapply.
-Emil _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel
What happened here? I can't really see my commit nor a revert nor a release in libdrm.
/Thomas
On Sun, 30 Sep 2018 at 18:31, Thomas Hellstrom thomas@shipmail.org wrote:
Hi, Emil,
On 09/05/2018 03:53 PM, Emil Velikov wrote:
On 5 September 2018 at 14:20, Thomas Hellstrom thellstrom@vmware.com wrote:
In that case, please give me 24h to do a libdrm release before pushing. I had to push some workarounds for the sandboxing mentioned earlier :-\
Thanks Emil
Ouch, I just pushed the patch, but feel free to cut the release just before that commit.
That doesn't quite work. Barring any objections I'll: revert, release, reapply.
-Emil _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel
What happened here? I can't really see my commit nor a revert nor a release in libdrm.
Coming back from holidays+XDC. I' m doing a release in a moment and will pick your patch just after that.
Hmm you said you pushed the patch, yet it's not in master ... Not sure what happened there. Either way - it'll be there shortly.
Thanks Emil
Hi, Emil,
On 10/04/2018 04:12 PM, Emil Velikov wrote:
On Sun, 30 Sep 2018 at 18:31, Thomas Hellstrom thomas@shipmail.org wrote:
Hi, Emil,
On 09/05/2018 03:53 PM, Emil Velikov wrote:
On 5 September 2018 at 14:20, Thomas Hellstrom thellstrom@vmware.com wrote:
In that case, please give me 24h to do a libdrm release before pushing. I had to push some workarounds for the sandboxing mentioned earlier :-\
Thanks Emil
Ouch, I just pushed the patch, but feel free to cut the release just before that commit.
That doesn't quite work. Barring any objections I'll: revert, release, reapply.
-Emil _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Flists.freed...
What happened here? I can't really see my commit nor a revert nor a release in libdrm.
Coming back from holidays+XDC. I' m doing a release in a moment and will pick your patch just after that.
Hmm you said you pushed the patch, yet it's not in master ... Not sure what happened there. Either way - it'll be there shortly.
Yes, that's strange. I'm offsite too so I can't check the system from which I pushed it. But anyway, I'll push it later today if you haven't already.
Thanks, Thomas
Thanks Emil
Am 31.08.2018 um 17:27 schrieb Emil Velikov:
On 31 August 2018 at 15:38, Michel Dänzer michel@daenzer.net wrote:
[ Adding the amd-gfx list ]
On 2018-08-31 3:05 p.m., Thomas Hellstrom wrote:
On 08/31/2018 02:30 PM, Emil Velikov wrote:
On 31 August 2018 at 12:54, Thomas Hellstrom thellstrom@vmware.com wrote:
To determine whether a device node is a drm device node or not, the code currently compares the node's major number to the static drm major device number.
This breaks the standalone vmwgfx driver on XWayland dri clients,
Any particular reason why the code doesn't use a fixed node there? It will make the diff vs the in-kernel driver a bit smaller.
Because then it won't be able to interoperate with other in-tree drivers, like virtual drm drivers or passthrough usb drm drivers. There is no clean way to share the minor number allocation with in-tree drm, so standalone vmwgfx is using dynamic major allocation.
I wonder why I haven't heard of any of these issues with the standalone version of amdgpu shipped in packaged AMD releases. Does that also use a different major number? If yes, maybe it's just that nobody has tried Xwayland clients with that driver. If no, how does it avoid the other issues described above?
AFAICT, the difference is that the standalone vmwgfx uses an internal copy of drm core. It doesn't reuse the in-kernel drm, hence it cannot know which minor it can use.
The amdgpu pro package has it's own drm core copy as well and there it still works.
Not sure how our back-porting guys handle that.
Christian.
-Emil _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel
On Fri, Aug 31, 2018 at 11:32 AM Christian König ckoenig.leichtzumerken@gmail.com wrote:
Am 31.08.2018 um 17:27 schrieb Emil Velikov:
On 31 August 2018 at 15:38, Michel Dänzer michel@daenzer.net wrote:
[ Adding the amd-gfx list ]
On 2018-08-31 3:05 p.m., Thomas Hellstrom wrote:
On 08/31/2018 02:30 PM, Emil Velikov wrote:
On 31 August 2018 at 12:54, Thomas Hellstrom thellstrom@vmware.com wrote:
To determine whether a device node is a drm device node or not, the code currently compares the node's major number to the static drm major device number.
This breaks the standalone vmwgfx driver on XWayland dri clients,
Any particular reason why the code doesn't use a fixed node there? It will make the diff vs the in-kernel driver a bit smaller.
Because then it won't be able to interoperate with other in-tree drivers, like virtual drm drivers or passthrough usb drm drivers. There is no clean way to share the minor number allocation with in-tree drm, so standalone vmwgfx is using dynamic major allocation.
I wonder why I haven't heard of any of these issues with the standalone version of amdgpu shipped in packaged AMD releases. Does that also use a different major number? If yes, maybe it's just that nobody has tried Xwayland clients with that driver. If no, how does it avoid the other issues described above?
AFAICT, the difference is that the standalone vmwgfx uses an internal copy of drm core. It doesn't reuse the in-kernel drm, hence it cannot know which minor it can use.
The amdgpu pro package has it's own drm core copy as well and there it still works.
We don't use our own copy of drm core in the kernel, we rely on the in kernel one. Just ttm and amdgpu are updated in the dkms packages.
Alex
Not sure how our back-porting guys handle that.
Christian.
-Emil _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel
amd-gfx mailing list amd-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/amd-gfx
dri-devel@lists.freedesktop.org
-
Alex Deucher -
Christian König -
Daniel Vetter -
Dave Airlie -
Emil Velikov -
Eric Engestrom -
Michel Dänzer -
Thomas Hellstrom -
Thomas Hellstrom