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Message-ID: <alpine.LFD.2.20.1605242135500.4622@casper.infradead.org> Date: Tue, 24 May 2016 21:38:19 +0100 (BST) From: James Simmons <jsimmons@...radead.org> To: Andreas Grünbacher <andreas.gruenbacher@...il.com> cc: Greg Kroah-Hartman <gregkh@...uxfoundation.org>, devel@...verdev.osuosl.org, Andreas Dilger <andreas.dilger@...el.com>, Oleg Drokin <oleg.drokin@...el.com>, Andreas Gruenbacher <agruenba@...hat.com>, Linux Kernel Mailing List <linux-kernel@...r.kernel.org>, Lustre Development List <lustre-devel@...ts.lustre.org> Subject: Re: [PATCH] staging: lustre: llite: drop acl from cache > 2016-05-24 2:35 GMT+02:00 James Simmons <jsimmons@...radead.org>: > > Commit b8a7a3a6 change get_acl() for posix xattr to always cache > > the ACL which increases the reference count. That reference count > > can be reduced by have ll_get_acl() call forget_cached_acl() which > > it wasn't. When an inode gets deleted by Lustre the POSIX ACL > > reference count is tested to ensure its 1 and if not produces an error. > > Lustre shouldn't assume that the VFS immediately drops the reference > it is passed. Please remove that check as well. The piece of code in question from ll_delete_inode() is #ifdef CONFIG_FS_POSIX_ACL else if (lli->lli_posix_acl) { LASSERT(atomic_read(&lli->lli_posix_acl->a_refcount) == 1); LASSERT(!lli->lli_remote_perms); posix_acl_release(lli->lli_posix_acl); lli->lli_posix_acl = NULL; } #endif So we want to prevent a leak should I do a while (atomic_read(&lli->lli_posix_acl->a_refcount)) posix_acl_release(lli->lli_posix_acl); lli->lli_posix_acl = NULL; Or does the VFS do this cleanup for us? > > Since forget_cached_acl() was not called Lustre started to complain. > > This patch changes ll_get_acl() to call forget_cached_acl(). > > > > Signed-off-by: James Simmons <jsimmons@...radead.org> > > Reviewed-by: Andreas Gruenbacher <agruenba@...hat.com> > > > --- > > drivers/staging/lustre/lustre/llite/file.c | 1 + > > 1 files changed, 1 insertions(+), 0 deletions(-) > > > > diff --git a/drivers/staging/lustre/lustre/llite/file.c b/drivers/staging/lustre/lustre/llite/file.c > > index f47f2ac..0191945 100644 > > --- a/drivers/staging/lustre/lustre/llite/file.c > > +++ b/drivers/staging/lustre/lustre/llite/file.c > > @@ -3124,6 +3124,7 @@ struct posix_acl *ll_get_acl(struct inode *inode, int type) > > spin_lock(&lli->lli_lock); > > /* VFS' acl_permission_check->check_acl will release the refcount */ > > acl = posix_acl_dup(lli->lli_posix_acl); > > + forget_cached_acl(inode, type); > > spin_unlock(&lli->lli_lock); > > > > return acl; > > -- > > 1.7.1 > > >
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