Chris Wilson 430ffaf46c drm/i915: Suppress switch_mm emission between the same aliasing_ppgtt ... When switching between contexts using the aliasing_ppgtt, the VM is shared. We don't need to reload the PD registers unless they are dirty. Martin Peres reported an issue that looks like corruption between Haswell context switches, bisecting to commit f9326be5f1 ("drm/i915: Rearrange switch_context to load the aliasing ppgtt on first use"). Switching between the same mm (the aliasing_ppgtt is used for all contexts in this case) should be a nop, but appears to trigger some side-effects in the context switch. However, as we know the switch is redundant in this case, we can skip it and continue to ignore the issue until somebody feels strong enough to investigate full-ppgtt on gen7 again! Except.. Martin was using full-ppgtt which is not supported as it doesn't work correctly yet. So whilst the bisect did yield valuable information about the failures, the fix should not have any user impact under default settings, with the exception of a slightly lower throughput on xcs as the VM would always be reloaded. v2: Also remember to set the legacy_active_context following the switch on xcs (commit e8a9c58fcd ("drm/i915: Unify active context tracking between legacy/execlists/guc")) Fixes: f9326be5f1 ("drm/i915: Rearrange switch_context to load the aliasing ppgtt on first use") Fixes: e8a9c58fcd ("drm/i915: Unify active context tracking between legacy/execlists/guc") Reported-by: Martin Peres <martin.peres@linux.intel.com> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Martin Peres <martin.peres@linux.intel.com> Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20170812152724.6883-1-chris@chris-wilson.co.uk (cherry picked from commit 12124bea5b) Signed-off-by: Jani Nikula <jani.nikula@intel.com>		2017-08-14 19:28:37 +03:00
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drm	drm/i915: Suppress switch_mm emission between the same aliasing_ppgtt	2017-08-14 19:28:37 +03:00
host1x	gpu: host1x: Free the IOMMU domain when there is no device to attach	2017-07-27 16:57:34 +02:00
ipu-v3	Linux 4.12-rc5	2017-06-16 13:58:27 +10:00
vga	sched/wait: Rename wait_queue_t => wait_queue_entry_t	2017-06-20 12:18:27 +02:00
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