From: Søren Sandmann Pedersen <s...@redhat.com> The fb layer of X can't deal with strides that are not a multiple of 4, so when Xephyr allocates its own framebuffer it should make sure to align it.
This fixes crashes and rendering corruption when Xephyr runs in a depth that is different from the host X server and its screen size is not a multiple of 4 / depth. (This is particularly easy to trigger if you use the -resizeable option). --- hw/kdrive/ephyr/hostx.c | 15 ++++++++------- 1 files changed, 8 insertions(+), 7 deletions(-) diff --git a/hw/kdrive/ephyr/hostx.c b/hw/kdrive/ephyr/hostx.c index 86f3679..b547525 100644 --- a/hw/kdrive/ephyr/hostx.c +++ b/hw/kdrive/ephyr/hostx.c @@ -719,12 +719,14 @@ hostx_screen_init(KdScreenInfo *screen, return scrpriv->ximg->data; } else { - *bytes_per_line = width * (scrpriv->server_depth >> 3); + int Bpp = scrpriv->server_depth >> 3; + int stride = (width * Bpp + 0x3) & ~0x3; + + *bytes_per_line = stride; *bits_per_pixel = scrpriv->server_depth; - EPHYR_DBG("server bpp %i", scrpriv->server_depth >> 3); - scrpriv->fb_data = - malloc(width * buffer_height * (scrpriv->server_depth >> 3)); + EPHYR_DBG("server bpp %i", Bpp); + scrpriv->fb_data = malloc (stride * buffer_height); return scrpriv->fb_data; } } @@ -763,15 +765,14 @@ hostx_paint_rect(KdScreenInfo *screen, if (!host_depth_matches_server(scrpriv)) { int x, y, idx, bytes_per_pixel = (scrpriv->server_depth >> 3); + int stride = (scrpriv->win_width * bytes_per_pixel + 0x3) & ~0x3; unsigned char r, g, b; unsigned long host_pixel; EPHYR_DBG("Unmatched host depth scrpriv=%p\n", scrpriv); for (y = sy; y < sy + height; y++) for (x = sx; x < sx + width; x++) { - idx = - (scrpriv->win_width * y * bytes_per_pixel) + - (x * bytes_per_pixel); + idx = y * stride + x * bytes_per_pixel; switch (scrpriv->server_depth) { case 16: -- 1.7.1 _______________________________________________ xorg-devel@lists.x.org: X.Org development Archives: http://lists.x.org/archives/xorg-devel Info: http://lists.x.org/mailman/listinfo/xorg-devel