On Fri, May 27, 2016 at 11:30:30AM +0300, ville.syrjala@xxxxxxxxxxxxxxx wrote: > From: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> > > Several nasty i915 regressions affecting CHV slipped through > to 4.5 and 4.6. > > The first fix we want in 4.5 and 4.6 is > commit caed361d83b2 ("drm/i915: Fix watermarks for VLV/CHV") > It won't cherry-pick cleanly to either one, so I've included conflict > free versions for both. This one fixes display FIFO underruns that can > lead to the screen totally blanking out. Now applied, thanks. > The other one I'd like to have in 4.6 is > commit 9f6151c90390 ("drm/i915: Pass the correct crtc state to .update_plane()") > which avoids a totally corrupted display in some cases. Now applied. > And the third on is a bit more annoying. The regression is caused by > commit 9dbaab56ac09 ("drm/i915: Exit cherryview_irq_handler() after one pass") > which I though we had prevented from getting out on its own, but turns > out I was wrong. It basically makes the GPU unusable, so we do need to > fix it somehow. The simple solution would be to revert it in 4.6 only. > The more complicated solution is to backport the proper fix, which more > or less requires the following set of commits [1], which is maybe a bit > too much for stable. I could try to trim it a bit perhaps, but then we > start to enter the territory of untested code which I don't particularly > like. Let me know what you think. > > [1] > 1e1cace942ef ("drm/i915: Eliminate loop from VLV irq handler") > a5e485a95c9c ("drm/i915: Clear VLV_IER around irq processing") > 4a0a0202b023 ("drm/i915: Clear VLV_MASTER_IER around irq processing") > 7ce4d1f2730f ("drm/i915: Clear VLV_IIR after PIPESTAT") > 34c7b8a7b8b5 ("drm/i915: Set up VLV_MASTER_IER consistently") > e5328c43d46e ("drm/i915: Use GEN8_MASTER_IRQ_CONTROL consistently") > 71b8b41d5b35 ("drm/i915: Move DPINVGTT setup to vlv_display_irq_reset()") > 6b7eafc1b43d ("drm/i915: Warn if irq_mask isn't ~0 during vlv/cvh display irq postinstall") > 9ab981f22bef ("drm/i915: Use GEN5_IRQ_INIT() in vlv_display_irq_postinstall()") > d6c698035892 ("drm/i915: Clear display interrupt before enabling when turning on the power well") > 8bb613068a63 ("drm/i915: Move vlv/chv display irq code to a more logical place") > 9918271efc7a ("drm/i915: Skip display irq setup if display irqs aren't flagged as enabled") > ad22d10654ea ("drm/i915: Fix up vlv/chv display irq setup") > 93de68f94081 ("drm/i915: Remove "VLV magic" from irq setup") I think reverting that one patch for 4.6 makes more sense than adding all of these patches. I'll do that if you want me to. thanks, greg k-h -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html