On Thu, 08 Jul 2021, Daire Byrne wrote: > On Wed, 7 Jul 2021 at 22:25, NeilBrown <neilb@xxxxxxx> wrote: > > > > That's pretty solid evidence! > > > > I just realized that the stack trace you reported mentions > > "kfree_const()". > > My latest patch doesn't include that, and nfs doesn't use it at all. > > Might you still be using the older patch? > > > > NeilBrown > > Oh... the last stack trace, the readdir one? I don't see kfree_const > myself but I may have a case of word blindness. The first one I > reported definitely has kfree_const but after your latest patch, this > last one around readdir doesn't seem to? > > I'm pretty sure I have your latest patch (with kfree instead of > kfree_const) correctly applied. Though, I will double check that the > correct kernel and modules were then installed properly on my test VM. sorry - my bad.. I think I've found it. Rather than sending the whole patch, here is the incremental fix. But not clearing this pointer, I risk the value in it being freed twice. That might lead to what you saw. Thanks, NeilBrown diff --git a/fs/nfs/fs_context.c b/fs/nfs/fs_context.c index 7c644a31d304..9e34af223ce6 100644 --- a/fs/nfs/fs_context.c +++ b/fs/nfs/fs_context.c @@ -1451,6 +1451,7 @@ static int nfs_fs_context_dup(struct fs_context *fc, struct fs_context *src_fc) ctx->nfs_server.export_path = NULL; ctx->nfs_server.hostname = NULL; ctx->fscache_uniq = NULL; + ctx->namespace = NULL; ctx->clone_data.fattr = NULL; fc->fs_private = ctx; return 0;
