| Message ID | 20240112042639.3948236-1-suhui@nfschina.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | ocfs2: remove useless code in ocfs2_try_to_merge_extent | expand |
On Fri, 12 Jan 2024 12:26:40 +0800 Su Hui <suhui@nfschina.com> wrote: > Clang static checker warning: Value stored to 'rec' is never read. > Remove this useless code to silent this warning. > > --- a/fs/ocfs2/alloc.c > +++ b/fs/ocfs2/alloc.c > @@ -3743,8 +3743,6 @@ static int ocfs2_try_to_merge_extent(handle_t *handle, > goto out; > } > > - rec = &el->l_recs[split_index]; > - > /* > * Note that we don't pass split_rec here on purpose - > * we've merged it into the rec already. Then: ret = ocfs2_merge_rec_left(path, handle, et, rec, dealloc, split_index); and ocfs2_merge_rec_left() almost immediately dereferences `rec'. So this looks quite wrong to me.
On 2024/1/17 04:09, Andrew Morton wrote: > On Fri, 12 Jan 2024 12:26:40 +0800 Su Hui <suhui@nfschina.com> wrote: > >> Clang static checker warning: Value stored to 'rec' is never read. >> Remove this useless code to silent this warning. >> >> --- a/fs/ocfs2/alloc.c >> +++ b/fs/ocfs2/alloc.c >> @@ -3743,8 +3743,6 @@ static int ocfs2_try_to_merge_extent(handle_t *handle, >> goto out; >> } >> >> - rec = &el->l_recs[split_index]; >> - >> /* >> * Note that we don't pass split_rec here on purpose - >> * we've merged it into the rec already. > Then: > > ret = ocfs2_merge_rec_left(path, handle, et, rec, > dealloc, split_index); > > and ocfs2_merge_rec_left() almost immediately dereferences `rec'. > > So this looks quite wrong to me. > Oh, really sorry for the noise. This patch is wrong. Su Hui
diff --git a/fs/ocfs2/alloc.c b/fs/ocfs2/alloc.c index ea9127ba3208..71729e4326d3 100644 --- a/fs/ocfs2/alloc.c +++ b/fs/ocfs2/alloc.c @@ -3743,8 +3743,6 @@ static int ocfs2_try_to_merge_extent(handle_t *handle, goto out; } - rec = &el->l_recs[split_index]; - /* * Note that we don't pass split_rec here on purpose - * we've merged it into the rec already.
Clang static checker warning: Value stored to 'rec' is never read. Remove this useless code to silent this warning. Signed-off-by: Su Hui <suhui@nfschina.com> --- fs/ocfs2/alloc.c | 2 -- 1 file changed, 2 deletions(-)