| Summary: | No /dev/dri with generation or 6 or later Intel GPU | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Product: | [Fedora] Fedora | Reporter: | Sylvia Else <sylviabz1> | ||||||
| Component: | kernel | Assignee: | Kernel Maintainer List <kernel-maint> | ||||||
| Status: | CLOSED NOTABUG | QA Contact: | Fedora Extras Quality Assurance <extras-qa> | ||||||
| Severity: | unspecified | Docs Contact: | |||||||
| Priority: | unspecified | ||||||||
| Version: | 19 | CC: | gansalmon, itamar, jonathan, kernel-maint, madhu.chinakonda, marcelo.barbosa, skottler | ||||||
| Target Milestone: | --- | ||||||||
| Target Release: | --- | ||||||||
| Hardware: | Unspecified | ||||||||
| OS: | Unspecified | ||||||||
| Whiteboard: | |||||||||
| Fixed In Version: | Doc Type: | Bug Fix | |||||||
| Doc Text: | Story Points: | --- | |||||||
| Clone Of: | Environment: | ||||||||
| Last Closed: | 2013-09-19 13:43:39 UTC | Type: | Bug | ||||||
| Regression: | --- | Mount Type: | --- | ||||||
| Documentation: | --- | CRM: | |||||||
| Verified Versions: | Category: | --- | |||||||
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |||||||
| Cloudforms Team: | --- | Target Upstream Version: | |||||||
| Attachments: |
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Description
Sylvia Else
2013-09-18 09:35:22 UTC
It seems that contrary to an earlier impression I had, putting options i915 modeset=1 into a file in the /etc/modprobe.d directory is also effective, with the added advantage that it doesn't mess up the screen during booting. Can you attach the output of dmesg with and without the modeset=1 parameter specified? *********** MASS BUG UPDATE ************** We apologize for the inconvenience. There is a large number of bugs to go through and several of them have gone stale. Due to this, we are doing a mass bug update across all of the Fedora 19 kernel bugs. Fedora 19 has now been rebased to 3.11.1-200.fc19. Please test this kernel update and let us know if you issue has been resolved or if it is still present with the newer kernel. If you experience different issues, please open a new bug report for those. I have tested against 3.11.1-200.fc19, and the behaviour is the same. In fact, the situation has become clear enough. In i915_dma.c, at line 1480, there is a test for the generation being >= 6 in the absence of modesetting, and the function bails with an error if so. Presumably modesetting is required for the thing to work. An error message would have been nice. Anyway, moving to i915_drv.c, line 1190, we see code (CONFIG_DRM_I915_KM is in fact set) that sets modesetting by default if the i915_modeset variable has been left at its initial value of -1. However the kernel line includes "nomodeset" which has the effect of clearing the i915_modeset variable to zero, thus preventing the default use of modesetting. I haven't been able to determine what it is that causes nomodeset to be included in the kernel line, but as long as its there, and in the absence of a modprobe to overcome it, the i915 module, and with it the direct rendering interface, is not going to be available with the recent GPUs. Created attachment 799756 [details]
dmesg with no modeset
demsg output with kernel line as installed.
Created attachment 799757 [details]
demsg with the "nomodeset" removed from the kernel command line
I have to retract my earlier observation that adding an option to the modprobe.d directory resolves the problem, at least without some other operation involving (I think) the installation of kernels (I'm unclear what the interaction is). It occurs to me now that the nomodeset on the kernel command line is probably there because I used the video-trouble shooting installation option. If so, then it was not clear that that would have ramifications well beyond the installation phase. (In reply to Sylvia Else from comment #8) > It occurs to me now that the nomodeset on the kernel command line is > probably there because I used the video-trouble shooting installation > option. If so, then it was not clear that that would have ramifications well > beyond the installation phase. Yes, that would do it. Please remove it from your grub configuration file. The kernel is doing exactly what it is told if nomodeset is specified on the command line. |