Merge lp:~alan-griffiths/mir/fix-1706718 into lp:mir

[Alan Griffiths]

[mesa-kms] Respect display orientation when painting cursor. (LP: #1610078)

[mesa-kms] Respect display orientation when painting cursor

The test changes are for three reasons:

1. they can no longer assume that the image data is not referenced and the pointer passed "straight through".

2. Throwing for "oversized image" isn't useful behaviour.

3. the hotspot should also rotate, so the expectations were wrong by the image size (64) in assorted directions.

[Mir CI Bot (mir-ci-bot)]

FAILED: Continuous integration, rev:4219
https://mir-jenkins.ubuntu.com/job/mir-ci/3513/
Executed test runs:
    FAILURE: https://mir-jenkins.ubuntu.com/job/build-mir/4808/console
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-0-fetch/4996
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-1-sourcepkg/release=artful/4985
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-1-sourcepkg/release=xenial/4985
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-1-sourcepkg/release=zesty/4985
    FAILURE: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=amd64,compiler=clang,platform=mesa,release=artful/4845/console
    FAILURE: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=amd64,compiler=clang,platform=mesa,release=zesty/4845/console
    FAILURE: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=amd64,compiler=gcc,platform=mesa,release=artful/4845/console
    FAILURE: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=amd64,compiler=gcc,platform=mesa,release=xenial/4845/console
    FAILURE: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=amd64,compiler=gcc,platform=mesa,release=zesty/4845/console
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=cross-armhf,compiler=gcc,platform=mesa,release=artful/4845
        deb: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=cross-armhf,compiler=gcc,platform=mesa,release=artful/4845/artifact/output/*zip*/output.zip
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        deb: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=cross-armhf,compiler=gcc,platform=mesa,release=zesty/4845/artifact/output/*zip*/output.zip
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review: Needs Fixing (continuous-integration)

[Alan Griffiths (alan-griffiths)]

Guess who forgot to run the tests. :(

[Mir CI Bot (mir-ci-bot)]

FAILED: Continuous integration, rev:4221
https://mir-jenkins.ubuntu.com/job/mir-ci/3514/
Executed test runs:
    FAILURE: https://mir-jenkins.ubuntu.com/job/build-mir/4809/console
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-0-fetch/4997
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-1-sourcepkg/release=artful/4986
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-1-sourcepkg/release=xenial/4986
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-1-sourcepkg/release=zesty/4986
    FAILURE: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=amd64,compiler=clang,platform=mesa,release=artful/4846/console
    FAILURE: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=amd64,compiler=clang,platform=mesa,release=zesty/4846/console
    FAILURE: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=amd64,compiler=gcc,platform=mesa,release=artful/4846/console
    FAILURE: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=amd64,compiler=gcc,platform=mesa,release=xenial/4846/console
    FAILURE: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=amd64,compiler=gcc,platform=mesa,release=zesty/4846/console
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=cross-armhf,compiler=gcc,platform=mesa,release=artful/4846
        deb: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=cross-armhf,compiler=gcc,platform=mesa,release=artful/4846/artifact/output/*zip*/output.zip
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=cross-armhf,compiler=gcc,platform=mesa,release=zesty/4846
        deb: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=cross-armhf,compiler=gcc,platform=mesa,release=zesty/4846/artifact/output/*zip*/output.zip
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review: Needs Fixing (continuous-integration)

[Mir CI Bot (mir-ci-bot)]

FAILED: Continuous integration, rev:4223
https://mir-jenkins.ubuntu.com/job/mir-ci/3515/
Executed test runs:
    FAILURE: https://mir-jenkins.ubuntu.com/job/build-mir/4810/console
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-0-fetch/4998
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-1-sourcepkg/release=artful/4987
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-1-sourcepkg/release=xenial/4987
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-1-sourcepkg/release=zesty/4987
    FAILURE: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=amd64,compiler=clang,platform=mesa,release=artful/4847/console
    FAILURE: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=amd64,compiler=clang,platform=mesa,release=zesty/4847/console
    FAILURE: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=amd64,compiler=gcc,platform=mesa,release=artful/4847/console
    FAILURE: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=amd64,compiler=gcc,platform=mesa,release=xenial/4847/console
    FAILURE: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=amd64,compiler=gcc,platform=mesa,release=zesty/4847/console
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=cross-armhf,compiler=gcc,platform=mesa,release=artful/4847
        deb: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=cross-armhf,compiler=gcc,platform=mesa,release=artful/4847/artifact/output/*zip*/output.zip
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=cross-armhf,compiler=gcc,platform=mesa,release=zesty/4847
        deb: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=cross-armhf,compiler=gcc,platform=mesa,release=zesty/4847/artifact/output/*zip*/output.zip
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review: Needs Fixing (continuous-integration)

[Mir CI Bot (mir-ci-bot)]

PASSED: Continuous integration, rev:4224
https://mir-jenkins.ubuntu.com/job/mir-ci/3516/
Executed test runs:
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-mir/4811
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-0-fetch/5000
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-1-sourcepkg/release=artful/4989
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-1-sourcepkg/release=xenial/4989
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-1-sourcepkg/release=zesty/4989
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=amd64,compiler=clang,platform=mesa,release=artful/4848
        deb: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=amd64,compiler=clang,platform=mesa,release=artful/4848/artifact/output/*zip*/output.zip
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=amd64,compiler=clang,platform=mesa,release=zesty/4848
        deb: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=amd64,compiler=clang,platform=mesa,release=zesty/4848/artifact/output/*zip*/output.zip
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=amd64,compiler=gcc,platform=mesa,release=artful/4848
        deb: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=amd64,compiler=gcc,platform=mesa,release=artful/4848/artifact/output/*zip*/output.zip
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=amd64,compiler=gcc,platform=mesa,release=xenial/4848
        deb: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=amd64,compiler=gcc,platform=mesa,release=xenial/4848/artifact/output/*zip*/output.zip
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=amd64,compiler=gcc,platform=mesa,release=zesty/4848
        deb: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=amd64,compiler=gcc,platform=mesa,release=zesty/4848/artifact/output/*zip*/output.zip
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=cross-armhf,compiler=gcc,platform=mesa,release=artful/4848
        deb: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=cross-armhf,compiler=gcc,platform=mesa,release=artful/4848/artifact/output/*zip*/output.zip
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=cross-armhf,compiler=gcc,platform=mesa,release=zesty/4848
        deb: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=cross-armhf,compiler=gcc,platform=mesa,release=zesty/4848/artifact/output/*zip*/output.zip
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=i386,compiler=gcc,platform=mesa,release=xenial/4848
        deb: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=i386,compiler=gcc,platform=mesa,release=xenial/4848/artifact/output/*zip*/output.zip

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review: Approve (continuous-integration)

[Gerry Boland (gerboland)]

Bug: changing display orientation doesn't cause cursor redraw (but does redraw scene). Only moving the mouse triggers the cursor redraw.

Testing directly on hardware, mir_demo_server and mir_demo_client_displayconfiguration

review: Needs Fixing

[Alan Griffiths (alan-griffiths)]

> Bug: changing display orientation doesn't cause cursor redraw (but does redraw
> scene). Only moving the mouse triggers the cursor redraw.
>
> Testing directly on hardware, mir_demo_server and
> mir_demo_client_displayconfiguration

Fixed

[Gerry Boland (gerboland)]

LGTM

Though the --x-cursor-theme arg doesn't seem to be doing anything when I try it..

review: Approve

[Mir CI Bot (mir-ci-bot)]

PASSED: Continuous integration, rev:4225
https://mir-jenkins.ubuntu.com/job/mir-ci/3517/
Executed test runs:
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-mir/4812
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-0-fetch/5010
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-1-sourcepkg/release=artful/4999
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-1-sourcepkg/release=xenial/4999
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-1-sourcepkg/release=zesty/4999
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=amd64,compiler=clang,platform=mesa,release=artful/4849
        deb: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=amd64,compiler=clang,platform=mesa,release=artful/4849/artifact/output/*zip*/output.zip
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=amd64,compiler=clang,platform=mesa,release=zesty/4849
        deb: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=amd64,compiler=clang,platform=mesa,release=zesty/4849/artifact/output/*zip*/output.zip
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=amd64,compiler=gcc,platform=mesa,release=artful/4849
        deb: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=amd64,compiler=gcc,platform=mesa,release=artful/4849/artifact/output/*zip*/output.zip
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=amd64,compiler=gcc,platform=mesa,release=xenial/4849
        deb: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=amd64,compiler=gcc,platform=mesa,release=xenial/4849/artifact/output/*zip*/output.zip
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        deb: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=amd64,compiler=gcc,platform=mesa,release=zesty/4849/artifact/output/*zip*/output.zip
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        deb: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=cross-armhf,compiler=gcc,platform=mesa,release=artful/4849/artifact/output/*zip*/output.zip
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review: Approve (continuous-integration)

=== modified file 'src/platforms/mesa/server/kms/cursor.cpp'
--- src/platforms/mesa/server/kms/cursor.cpp	2017-07-20 14:11:27 +0000
+++ src/platforms/mesa/server/kms/cursor.cpp	2017-07-28 15:12:01 +0000
@@ -100,7 +100,7 @@
 }
 }
 
-mgm::Cursor::GBMBOWrapper::GBMBOWrapper(int fd) :
+mgm::Cursor::GBMBOWrapper::GBMBOWrapper(int fd, MirOrientation orientation) :
     device{gbm_create_device_checked(fd)},
     buffer{
         gbm_bo_create(
@@ -108,7 +108,8 @@
             get_drm_cursor_width(fd),
             get_drm_cursor_height(fd),
             GBM_FORMAT_ARGB8888,
-            GBM_BO_USE_CURSOR | GBM_BO_USE_WRITE)}
+            GBM_BO_USE_CURSOR | GBM_BO_USE_WRITE)},
+    current_orientation{orientation}
 {
     if (!buffer) BOOST_THROW_EXCEPTION(std::runtime_error("failed to create gbm buffer"));
 }
@@ -128,12 +129,22 @@
 
 mgm::Cursor::GBMBOWrapper::GBMBOWrapper(GBMBOWrapper&& from)
     : device{from.device},
-      buffer{from.buffer}
+      buffer{from.buffer},
+      current_orientation{from.current_orientation}
 {
     from.buffer = nullptr;
     from.device = nullptr;
 }
 
+auto mir::graphics::mesa::Cursor::GBMBOWrapper::change_orientation(MirOrientation new_orientation) -> bool
+{
+    if (current_orientation == new_orientation)
+        return false;
+
+    current_orientation = new_orientation;
+    return true;
+}
+
 mgm::Cursor::Cursor(
     KMSOutputContainer& output_container,
     std::shared_ptr<CurrentConfiguration> const& current_configuration) :
@@ -182,37 +193,86 @@
 
 void mgm::Cursor::pad_and_write_image_data_locked(
     std::lock_guard<std::mutex> const& lg,
-    gbm_bo* buffer,
-    CursorImage const& image)
+    GBMBOWrapper& buffer)
 {
-    auto image_argb = static_cast<uint8_t const*>(image.as_argb_8888());
-    auto image_width = image.size().width.as_uint32_t();
-    auto image_height = image.size().height.as_uint32_t();
-    auto image_stride = image_width * 4;
-
-    if (image_width > min_buffer_width || image_height > min_buffer_height)
-    {
-        BOOST_THROW_EXCEPTION(std::logic_error("Image is too big for GBM cursor buffer"));
-    }
-
-    size_t buffer_stride = gbm_bo_get_stride(buffer);  // in bytes
-    size_t padded_size = buffer_stride * gbm_bo_get_height(buffer);
+    auto const orientation = buffer.orientation();
+    bool const sideways = orientation == mir_orientation_left || orientation == mir_orientation_right;
+
+    auto const min_width  = sideways ? min_buffer_width : min_buffer_height;
+    auto const min_height = sideways ? min_buffer_height : min_buffer_width;
+
+    auto const image_width = std::min(min_width, size.width.as_uint32_t());
+    auto const image_height = std::min(min_height, size.height.as_uint32_t());
+    auto const image_stride = size.width.as_uint32_t() * 4;
+
+    auto const buffer_stride = std::max(min_width*4, gbm_bo_get_stride(buffer));  // in bytes
+    auto const buffer_height = std::max(min_height, gbm_bo_get_height(buffer));
+    size_t const padded_size = buffer_stride * buffer_height;
+
     auto padded = std::unique_ptr<uint8_t[]>(new uint8_t[padded_size]);
-    size_t rhs_padding = buffer_stride - image_stride;
+    size_t rhs_padding = buffer_stride - 4*image_width;
 
+    auto const filler = 0; // 0x3f; is useful to make buffer visible for debugging
+    uint8_t const* src = argb8888.data();
     uint8_t* dest = &padded[0];
-    uint8_t const* src = image_argb;
 
-    for (unsigned int y = 0; y < image_height; y++)
+    switch (orientation)
     {
-        memcpy(dest, src, image_stride);
-        memset(dest + image_stride, 0, rhs_padding);
-        dest += buffer_stride;
-        src += image_stride;
+    case mir_orientation_normal:
+        for (unsigned int y = 0; y < image_height; y++)
+        {
+            memcpy(dest, src, 4*image_width);
+            memset(dest + 4*image_width, filler, rhs_padding);
+            dest += buffer_stride;
+            src += image_stride;
+        }
+
+        memset(dest, 0, buffer_stride * (buffer_height - image_height));
+        break;
+
+    case mir_orientation_inverted:
+        for (unsigned int row = 0; row != image_height; ++row)
+        {
+            memset(dest+row*buffer_stride+4*image_width, filler, rhs_padding);
+
+            for (unsigned int col = 0; col != image_width; ++col)
+            {
+                memcpy(dest+row*buffer_stride+4*col, src + ((image_height-1)-row)*image_stride + 4*((image_width-1)-col), 4);
+            }
+        }
+
+        memset(dest+image_height*buffer_stride, filler, buffer_stride * (buffer_height - image_height));
+        break;
+
+    case mir_orientation_left:
+        for (unsigned int row = 0; row != image_width; ++row)
+        {
+            memset(dest+row*buffer_stride+4*image_height, filler, rhs_padding);
+
+            for (unsigned int col = 0; col != image_height; ++col)
+            {
+                memcpy(dest+row*buffer_stride+4*col, src + ((image_width-1)-row)*4 + image_stride*col, 4);
+            }
+        }
+
+        memset(dest+image_width*buffer_stride, filler, buffer_stride * (buffer_height - image_width));
+        break;
+
+    case mir_orientation_right:
+        for (unsigned int row = 0; row != image_width; ++row)
+        {
+            memset(dest+row*buffer_stride+4*image_height, filler, rhs_padding);
+
+            for (unsigned int col = 0; col != image_height; ++col)
+            {
+                memcpy(dest+row*buffer_stride+4*col, src + row*4 + image_stride*((image_height-1)-col), 4);
+            }
+        }
+
+        memset(dest+image_width*buffer_stride, filler, buffer_stride * (buffer_height - image_width));
+        break;
     }
 
-    memset(dest, 0, buffer_stride * (gbm_bo_get_height(buffer) - image_height));
-
     write_buffer_data_locked(lg, buffer, &padded[0], padded_size);
 }
 
@@ -231,23 +291,17 @@
 {
     std::lock_guard<std::mutex> lg(guard);
 
-    auto const& size = cursor_image.size();
+    size = cursor_image.size();
+
+    argb8888.resize(size.width.as_uint32_t() * size.height.as_uint32_t() * 4);
+    memcpy(argb8888.data(), cursor_image.as_argb_8888(), argb8888.size());
 
     hotspot = cursor_image.hotspot();
     {
         auto locked_buffers = buffers.lock();
         for (auto& pair : *locked_buffers)
         {
-            auto& buffer = pair.second;
-            if (size != geometry::Size{gbm_bo_get_width(buffer), gbm_bo_get_height(buffer)})
-            {
-                pad_and_write_image_data_locked(lg, buffer, cursor_image);
-            }
-            else
-            {
-                auto const count = size.width.as_uint32_t() * size.height.as_uint32_t() * sizeof(uint32_t);
-                write_buffer_data_locked(lg, buffer, cursor_image.as_argb_8888(), count);
-            }
+            pad_and_write_image_data_locked(lg, pair.second);
         }
     }
 
@@ -317,7 +371,7 @@
 }
 
 void mgm::Cursor::place_cursor_at_locked(
-    std::lock_guard<std::mutex> const&,
+    std::lock_guard<std::mutex> const& lg,
     geometry::Point position,
     ForceCursorState force_state)
 {
@@ -334,15 +388,23 @@
         if (output_rect.contains(position))
         {
             auto dp = transform(output_rect, position - output_rect.top_left, orientation);
+            auto hs = transform(geom::Rectangle{{0,0}, size}, hotspot, orientation);
 
             // It's a little strange that we implement hotspot this way as there is
             // drmModeSetCursor2 with hotspot support. However it appears to not actually
             // work on radeon and intel. There also seems to be precedent in weston for
             // implementing hotspot in this fashion.
-            output.move_cursor(geom::Point{} + dp - hotspot);
-            if (force_state || !output.has_cursor()) // TODO - or if orientation had changed - then set buffer..
+            output.move_cursor(geom::Point{} + dp - hs);
+            auto& buffer = buffer_for_output(output);
+
+            auto const changed_orientation = buffer.change_orientation(orientation);
+
+            if (changed_orientation)
+                pad_and_write_image_data_locked(lg, buffer);
+
+            if (force_state || !output.has_cursor() || changed_orientation)
             {
-                if (!output.set_cursor(buffer_for_output(output)) || !output.has_cursor())
+                if (!output.set_cursor(buffer) || !output.has_cursor())
                     set_on_all_outputs = false;
             }
         }
@@ -358,7 +420,7 @@
     last_set_failed = !set_on_all_outputs;
 }
 
-gbm_bo* mgm::Cursor::buffer_for_output(KMSOutput const& output)
+mgm::Cursor::GBMBOWrapper& mgm::Cursor::buffer_for_output(KMSOutput const& output)
 {
     auto locked_buffers = buffers.lock();
 
@@ -366,18 +428,18 @@
         locked_buffers->begin(),
         locked_buffers->end(),
         [&output](auto const& candidate)
-        {
-            return candidate.first == output.drm_fd();
-        });
+            {
+                return candidate.first == output.drm_fd();
+            });
 
     if (buffer_it != locked_buffers->end())
     {
         return buffer_it->second;
     }
 
-    locked_buffers->push_back(std::make_pair(output.drm_fd(), GBMBOWrapper(output.drm_fd())));
+    locked_buffers->push_back(std::make_pair(output.drm_fd(), GBMBOWrapper(output.drm_fd(), mir_orientation_normal)));
 
-    gbm_bo* bo = locked_buffers->back().second;
+    GBMBOWrapper& bo = locked_buffers->back().second;
     if (gbm_bo_get_width(bo) < min_buffer_width)
     {
         min_buffer_width = gbm_bo_get_width(bo);

=== modified file 'src/platforms/mesa/server/kms/cursor.h'
--- src/platforms/mesa/server/kms/cursor.h	2017-06-08 08:34:56 +0000
+++ src/platforms/mesa/server/kms/cursor.h	2017-07-28 15:12:01 +0000
@@ -85,6 +85,7 @@
 
 private:
     enum ForceCursorState { UpdateState, ForceState };
+    struct GBMBOWrapper;
     void for_each_used_output(std::function<void(KMSOutput&, geometry::Rectangle const&, MirOrientation orientation)> const& f);
     void place_cursor_at(geometry::Point position, ForceCursorState force_state);
     void place_cursor_at_locked(std::lock_guard<std::mutex> const&, geometry::Point position, ForceCursorState force_state);
@@ -95,31 +96,37 @@
         size_t count);
     void pad_and_write_image_data_locked(
         std::lock_guard<std::mutex> const&,
-        gbm_bo* buffer,
-        CursorImage const& image);
+        GBMBOWrapper& buffer);
     void clear(std::lock_guard<std::mutex> const&);
 
-    gbm_bo* buffer_for_output(KMSOutput const& output);
+    GBMBOWrapper& buffer_for_output(KMSOutput const& output);
     
     std::mutex guard;
 
     KMSOutputContainer& output_container;
     geometry::Point current_position;
     geometry::Displacement hotspot;
+    geometry::Size size;
+    std::vector<uint8_t> argb8888;
 
     bool visible;
     bool last_set_failed;
 
     struct GBMBOWrapper
     {
-        GBMBOWrapper(int fd);
+        GBMBOWrapper(int fd, MirOrientation orientation);
         operator gbm_bo*();
+
+        auto orientation() const -> MirOrientation { return current_orientation; }
+        auto change_orientation(MirOrientation new_orientation) -> bool;
+
         ~GBMBOWrapper();
 
         GBMBOWrapper(GBMBOWrapper&& from);
     private:
         gbm_device* device;
         gbm_bo* buffer;
+        MirOrientation current_orientation;
         GBMBOWrapper(GBMBOWrapper const&) = delete;
         GBMBOWrapper& operator=(GBMBOWrapper const&) = delete;
     };

=== modified file 'src/platforms/mesa/server/kms/display.cpp'
--- src/platforms/mesa/server/kms/display.cpp	2017-06-07 08:29:04 +0000
+++ src/platforms/mesa/server/kms/display.cpp	2017-07-28 15:12:01 +0000
@@ -420,14 +420,20 @@
 bool mgm::Display::apply_if_configuration_preserves_display_buffers(
     mg::DisplayConfiguration const& conf)
 {
+    bool result = false;
     auto const& new_kms_conf = dynamic_cast<RealKMSDisplayConfiguration const&>(conf);
-    std::lock_guard<decltype(configuration_mutex)> lock{configuration_mutex};
-    if (compatible(current_display_configuration, new_kms_conf))
+
     {
-        configure_locked(new_kms_conf, lock);
-        return true;
+        std::lock_guard<decltype(configuration_mutex)> lock{configuration_mutex};
+        if (compatible(current_display_configuration, new_kms_conf))
+        {
+            configure_locked(new_kms_conf, lock);
+            result = true;
+        }
     }
-    return false;
+
+    if (auto c = cursor.lock()) c->resume();
+    return result;
 }
 
 mg::Frame mgm::Display::last_frame_on(unsigned output_id) const

=== modified file 'tests/unit-tests/platforms/mesa/kms/test_cursor.cpp'
--- tests/unit-tests/platforms/mesa/kms/test_cursor.cpp	2017-06-07 08:29:04 +0000
+++ tests/unit-tests/platforms/mesa/kms/test_cursor.cpp	2017-07-28 15:12:01 +0000
@@ -272,7 +272,9 @@
 
     static void const* image_data;
 };
-void const* StubCursorImage::image_data = reinterpret_cast<void*>(&StubCursorImage::image_data);
+
+char const stub_data[128*128*4] = { 0 };
+void const* StubCursorImage::image_data = stub_data;
 
 // Those new cap flags are currently only available in drm/drm.h but not in
 // libdrm/drm.h nor in xf86drm.h. Additionally drm/drm.h is current c++ unfriendly
@@ -407,7 +409,7 @@
     geom::Size const cursor_size{cursor_side, cursor_side};
     size_t const cursor_size_bytes{cursor_side * cursor_side * sizeof(uint32_t)};
 
-    EXPECT_CALL(mock_gbm, gbm_bo_write(mock_gbm.fake_gbm.bo, StubCursorImage::image_data, cursor_size_bytes));
+    EXPECT_CALL(mock_gbm, gbm_bo_write(mock_gbm.fake_gbm.bo, NotNull(), cursor_size_bytes));
 
     cursor.show(image);
 }
@@ -464,7 +466,7 @@
     cursor_tmp.show(SinglePixelCursorImage());
 }
 
-TEST_F(MesaCursorTest, throws_when_images_are_too_large)
+TEST_F(MesaCursorTest, does_not_throw_when_images_are_too_large)
 {
     using namespace testing;
 
@@ -478,9 +480,7 @@
         geom::Size const large_cursor_size{cursor_side, cursor_side};
     };
 
-    EXPECT_THROW({
-        cursor.show(LargeCursorImage());
-    }, std::logic_error);
+    cursor.show(LargeCursorImage());
 }
 
 TEST_F(MesaCursorTest, clears_cursor_state_on_construction)
@@ -607,8 +607,9 @@
 
     current_configuration.conf.set_orentation_of_output(mg::DisplayConfigurationOutputId{2}, mir_orientation_left);
 
-    EXPECT_CALL(*output_container.outputs[2], move_cursor(geom::Point{112,100}));
-    EXPECT_CALL(*output_container.outputs[2], move_cursor(geom::Point{150,96}));
+    InSequence seq;
+    EXPECT_CALL(*output_container.outputs[2], move_cursor(geom::Point{112, 36}));
+    EXPECT_CALL(*output_container.outputs[2], move_cursor(geom::Point{150, 32}));
 
     cursor.move_to({766, 112});
     cursor.move_to({770, 150});
@@ -625,9 +626,9 @@
 
     current_configuration.conf.set_orentation_of_output(mg::DisplayConfigurationOutputId{2}, mir_orientation_right);
 
-
-    EXPECT_CALL(*output_container.outputs[2], move_cursor(geom::Point{688,100}));
-    EXPECT_CALL(*output_container.outputs[2], move_cursor(geom::Point{650,104}));
+    InSequence seq;
+    EXPECT_CALL(*output_container.outputs[2], move_cursor(geom::Point{624, 100}));
+    EXPECT_CALL(*output_container.outputs[2], move_cursor(geom::Point{586, 104}));
 
     cursor.move_to({766, 112});
     cursor.move_to({770, 150});
@@ -643,8 +644,9 @@
 
     current_configuration.conf.set_orentation_of_output(mg::DisplayConfigurationOutputId{2}, mir_orientation_inverted);
 
-    EXPECT_CALL(*output_container.outputs[2], move_cursor(geom::Point{700,88}));
-    EXPECT_CALL(*output_container.outputs[2], move_cursor(geom::Point{696,50}));
+    InSequence seq;
+    EXPECT_CALL(*output_container.outputs[2], move_cursor(geom::Point{636, 24}));
+    EXPECT_CALL(*output_container.outputs[2], move_cursor(geom::Point{632,-14}));
 
     cursor.move_to({766, 112});
     cursor.move_to({770, 150});