diff --git a/src/gallium/drivers/llvmpipe/lp_screen.c b/src/gallium/drivers/llvmpipe/lp_screen.c

index 5ec1df6..a0406fc 100644

--- a/src/gallium/drivers/llvmpipe/lp_screen.c

+++ b/src/gallium/drivers/llvmpipe/lp_screen.c

@@ -306,6 +306,13 @@ llvmpipe_is_format_supported( struct pipe_screen *_screen,

    if (!format_desc)

       return FALSE;

+   if ((bind & PIPE_BIND_RENDER_TARGET) &&

+       format != PIPE_FORMAT_R9G9B9E5_FLOAT &&

+       format != PIPE_FORMAT_R11G11B10_FLOAT &&

+       util_format_is_float(format)) {

+      return FALSE;

+   }

+

    assert(target == PIPE_BUFFER ||

           target == PIPE_TEXTURE_1D ||

           target == PIPE_TEXTURE_1D_ARRAY ||

diff --git a/src/gallium/drivers/softpipe/sp_screen.c b/src/gallium/drivers/softpipe/sp_screen.c

index 937035e..2f5e571 100644

--- a/src/gallium/drivers/softpipe/sp_screen.c

+++ b/src/gallium/drivers/softpipe/sp_screen.c

@@ -291,6 +291,13 @@ softpipe_is_format_supported( struct pipe_screen *screen,

    if (!format_desc)

       return FALSE;

+   if ((bind & PIPE_BIND_RENDER_TARGET) &&

+       format != PIPE_FORMAT_R9G9B9E5_FLOAT &&

+       format != PIPE_FORMAT_R11G11B10_FLOAT &&

+       util_format_is_float(format)) {

+      return FALSE;

+   }

+

    if (sample_count > 1)

       return FALSE;