On 15/03/22 2:35 pm, Paul Menzel wrote:
Dear Arunpravin,
Am 15.03.22 um 10:01 schrieb Arunpravin:
On 15/03/22 1:49 pm, Paul Menzel wrote:
Am 14.03.22 um 20:40 schrieb Arunpravin:
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.PaneerSelvam@amd.com
Please use your full name.
okay
You might also configure that in your email program.
yes
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
In what tree is that file?
drm-tip - https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fcgit.freed... drm-misc-next - https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fcgit.freed...
@@ -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; }Thank you for the hint. So the whole function is:
do { order = min(order, (unsigned int)fls(pages) - 1); BUG_ON(order > mm->max_order); BUG_ON(order < min_order);
do { if (flags & DRM_BUDDY_RANGE_ALLOCATION) /* Allocate traversing within the range */ block = alloc_range_bias(mm, start, end, order); else /* Allocate from freelist */ block = alloc_from_freelist(mm, order, flags); if (!IS_ERR(block)) break; if (order-- == min_order) { err = -ENOSPC; goto err_free; } } while (1); mark_allocated(block); mm->avail -= drm_buddy_block_size(mm, block); kmemleak_update_trace(block); list_add_tail(&block->link, &allocated); pages -= BIT(order); if (!pages) break;} while (1);
Was the BUG_ON triggered for your case?
BUG_ON(order < min_order);
no, this BUG_ON is not triggered for this bug
Please give more details.
there is a chance when there is no space to allocate, order value decrements and reaches to 0 at one point, here we should exit the loop, otherwise, further order value decrements to -1 and do..while loop doesn't exit. Hence added a check to exit the loop if order value becomes 0.
Thanks, Arun
Kind regards,
Paul