The old style of memory interleaving swizzled upto the end of the first even bank of memory, and then used the remainder as unswizzled on the unpaired bank - i.e. swizzling is not constant for all memory. This causes problems when we try to migrate memory and so the kernel prevents migration at all when we detect L-shaped inconsistent swizzling. However, this issue also extends to userspace who try to manually detile into memory as the swizzling for an individual page is unknown (it depends on its physical address only known to the kernel), userspace cannot correctly swizzle. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=91105 Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> Cc: Daniel Vetter <daniel.vetter@xxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx --- drivers/gpu/drm/i915/i915_gem_tiling.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/i915_gem_tiling.c b/drivers/gpu/drm/i915/i915_gem_tiling.c index d16585f788ea..ff96ae9b77bc 100644 --- a/drivers/gpu/drm/i915/i915_gem_tiling.c +++ b/drivers/gpu/drm/i915/i915_gem_tiling.c @@ -447,7 +447,10 @@ i915_gem_get_tiling(struct drm_device *dev, void *data, } /* Hide bit 17 from the user -- see comment in i915_gem_set_tiling */ - args->phys_swizzle_mode = args->swizzle_mode; + if (dev_priv->quirks & QUIRK_PIN_SWIZZLED_PAGES) + args->phys_swizzle_mode = I915_BIT_6_SWIZZLE_UNKNOWN; + else + args->phys_swizzle_mode = args->swizzle_mode; if (args->swizzle_mode == I915_BIT_6_SWIZZLE_9_17) args->swizzle_mode = I915_BIT_6_SWIZZLE_9; if (args->swizzle_mode == I915_BIT_6_SWIZZLE_9_10_17) -- 2.1.4 -- 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