From a0873490660246db587849a9e172f2b7b21fa88a Mon Sep 17 00:00:00 2001 From: Filipe Manana Date: Thu, 13 Dec 2018 21:16:56 +0000 Subject: Btrfs: setup a nofs context for memory allocation at __btrfs_set_acl We are holding a transaction handle when setting an acl, therefore we can not allocate the xattr value buffer using GFP_KERNEL, as we could deadlock if reclaim is triggered by the allocation, therefore setup a nofs context. Fixes: 39a27ec1004e8 ("btrfs: use GFP_KERNEL for xattr and acl allocations") CC: stable@vger.kernel.org # 4.9+ Reviewed-by: Nikolay Borisov Signed-off-by: Filipe Manana Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/acl.c | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'fs/btrfs/acl.c') diff --git a/fs/btrfs/acl.c b/fs/btrfs/acl.c index 3b66c957ea6f..5810463dc6d2 100644 --- a/fs/btrfs/acl.c +++ b/fs/btrfs/acl.c @@ -9,6 +9,7 @@ #include #include #include +#include #include #include "ctree.h" @@ -72,8 +73,16 @@ static int __btrfs_set_acl(struct btrfs_trans_handle *trans, } if (acl) { + unsigned int nofs_flag; + size = posix_acl_xattr_size(acl->a_count); + /* + * We're holding a transaction handle, so use a NOFS memory + * allocation context to avoid deadlock if reclaim happens. + */ + nofs_flag = memalloc_nofs_save(); value = kmalloc(size, GFP_KERNEL); + memalloc_nofs_restore(nofs_flag); if (!value) { ret = -ENOMEM; goto out; -- cgit v1.2.3