Re: [Intel-gfx] [PATCH] drm: Fix a infinite loop condition when order becomes 0

[Matthew Auld]

On 14/03/2022 19:40, Arunpravin wrote:
handle a situation in the condition order-- == min_order,
when order = 0, leading to order = -1, it now won't exit
the loop. To avoid this problem, added a order check in
the same condition, (i.e) when order is 0, we return
-ENOSPC
Signed-off-by: Arunpravin <arunpravin.paneersel...@amd.com>

Hmm, it sounded like we were instead going to go with the round_up(size, 
min_page_size), or check and bail if the size is misaligned, in which 
case we don't need this, AFAICT.

---
  drivers/gpu/drm/drm_buddy.c | 2 +-
  1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/drm_buddy.c b/drivers/gpu/drm/drm_buddy.c
index 72f52f293249..5ab66aaf2bbd 100644
--- a/drivers/gpu/drm/drm_buddy.c
+++ b/drivers/gpu/drm/drm_buddy.c
@@ -685,7 +685,7 @@ int drm_buddy_alloc_blocks(struct drm_buddy *mm,
                        if (!IS_ERR(block))
                                break;
  
-			if (order-- == min_order) {
+                       if (!order || order-- == min_order) {
                                err = -ENOSPC;
                                goto err_free;
                        }