| Message ID | 20230901065203.125150-1-yinjun.zhang@corigine.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 7fd525f67cf5176340421f598bfaef65ecd0b8c8 |
| Delegated to: | Michal Kubecek |
| Headers | show |
| Series | [v2,ethtool] rxclass: fix a bug in rmgr when searching for empty slot | expand |
| Context | Check | Description |
|---|---|---|
| netdev/tree_selection | success | Not a local patch |
Hello: This patch was applied to ethtool/ethtool.git (master) by Michal Kubecek <mkubecek@suse.cz>: On Fri, 1 Sep 2023 14:52:03 +0800 you wrote: > When reverse searching the list in rmgr for a free location the last > slot (first slot searched) in the list needs special care as it might > not span the full word length. This is done by building a bit-mask > covering the not-active parts of the last word and using that to judge > if there is a free location in the last word or not. Once that is known > searching in the last slot, or to skip it, can be done by the same > algorithm as for the other slots in the list. > > [...] Here is the summary with links: - [v2,ethtool] rxclass: fix a bug in rmgr when searching for empty slot https://git.kernel.org/pub/scm/network/ethtool/ethtool.git/commit/?id=7fd525f67cf5 You are awesome, thank you!
diff --git a/rxclass.c b/rxclass.c index 66cf00ba7728..f17e3a5124c0 100644 --- a/rxclass.c +++ b/rxclass.c @@ -446,7 +446,7 @@ static int rmgr_find_empty_slot(struct rmgr_ctrl *rmgr, * If loc rolls over it should be greater than or equal to rmgr->size * and as such we know we have reached the end of the list. */ - if (!~(rmgr->slot[slot_num] | (~1UL << rmgr->size % BITS_PER_LONG))) { + if (!~(rmgr->slot[slot_num] | (~1UL << loc % BITS_PER_LONG))) { loc -= 1 + (loc % BITS_PER_LONG); slot_num--; }
When reverse searching the list in rmgr for a free location the last slot (first slot searched) in the list needs special care as it might not span the full word length. This is done by building a bit-mask covering the not-active parts of the last word and using that to judge if there is a free location in the last word or not. Once that is known searching in the last slot, or to skip it, can be done by the same algorithm as for the other slots in the list. There is a bug in creating the bit-mask for the non-active parts of the last slot where the 0-indexed nature of bit addressing is not taken into account when shifting. This leads to a one-off bug, fix it. Fixes: 8d63f72ccdcb ("Add RX packet classification interface") Signed-off-by: Yinjun Zhang <yinjun.zhang@corigine.com> Cc: Alexander Duyck <alexanderduyck@meta.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@corigine.com> --- Change since v1: Use `loc` instead of `rmgr->size - 1` as suggested by Alexander. --- rxclass.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)