From 897c54d522ab960a879b763a15e489f630c491ee Mon Sep 17 00:00:00 2001 From: Thomas Hellstrom Date: Thu, 11 Jan 2018 10:19:23 +0100 Subject: [PATCH] loader/dri3: Avoid freeing renderbuffers in use MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Upon reception of an event that lowered the number of active back buffers, the code would immediately try to free all back buffers with an id equal to or higher than the new number of active back buffers. However, that could lead to an active or to-be-active back buffer being freed, since the old number of back buffers was used when obtaining an idle back buffer for use. This lead to crashes when lowering the number of active back buffers by transitioning from page-flipping to non-page-flipping presents. Fix this by computing the number of active back buffers only when trying to obtain a new back buffer. Fixes: 15e208c4cc ("loader/dri3: Don't accidently free buffer holding new back content") Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=104214 Cc: "17.3" Tested-by: Andriy.Khulap Tested-by: Vadym Shovkoplias Reviewed-by: Michel Dänzer Signed-off-by: Thomas Hellstrom --- src/loader/loader_dri3_helper.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/src/loader/loader_dri3_helper.c b/src/loader/loader_dri3_helper.c index cc890bc923..8f8efcb646 100644 --- a/src/loader/loader_dri3_helper.c +++ b/src/loader/loader_dri3_helper.c @@ -205,7 +205,6 @@ void loader_dri3_set_swap_interval(struct loader_dri3_drawable *draw, int interval) { draw->swap_interval = interval; - dri3_update_num_back(draw); } /** dri3_free_render_buffer @@ -377,7 +376,6 @@ dri3_handle_present_event(struct loader_dri3_drawable *draw, draw->flipping = false; break; } - dri3_update_num_back(draw); if (draw->vtable->show_fps) draw->vtable->show_fps(draw, ce->ust); @@ -402,7 +400,8 @@ dri3_handle_present_event(struct loader_dri3_drawable *draw, buf->busy = 0; if (buf && draw->num_back <= b && b < LOADER_DRI3_MAX_BACK && - draw->cur_blit_source != b) { + draw->cur_blit_source != b && + !buf->busy) { dri3_free_render_buffer(draw, buf); draw->buffers[b] = NULL; } @@ -537,6 +536,7 @@ dri3_find_back(struct loader_dri3_drawable *draw) /* Check whether we need to reuse the current back buffer as new back. * In that case, wait until it's not busy anymore. */ + dri3_update_num_back(draw); num_to_consider = draw->num_back; if (!loader_dri3_have_image_blit(draw) && draw->cur_blit_source != -1) { num_to_consider = 1; -- 2.15.1