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Subject[RFC PATCH V2 28/38] riscv: s64ilp32: Temporary workaround solution to gcc problem
Date
From: Guo Ren <guoren@linux.alibaba.com>

There is an existing problem in 64ilp32 gcc that combines two pointers
in one register. Liao is solving that problem. Before he finishes the
job, we could prevent it with a simple noinline attribute, fortunately.

struct path {
struct vfsmount *mnt;
struct dentry *dentry;
} __randomize_layout;

struct nameidata {
struct path path;
struct qstr last;
struct path root;
...
} __randomize_layout;

struct nameidata *nd
...
nd->path = nd->root;
6c88 ld a0,24(s1)
^^ // Wrong arg of mntget
e088 sd a0,0(s1)
// Need inserting "lw a0,0(s1)" here
mntget(path->mnt);
2a6150ef jal c01ce946 <mntget>

Any gcc helps are welcome :)

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Signed-off-by: Guo Ren <guoren@kernel.org>
Cc: LiaoShihua <shihua@iscas.ac.cn>
---
fs/namei.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/namei.c b/fs/namei.c
index e56ff39a79bc..1285736dadc4 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -543,7 +543,7 @@ EXPORT_SYMBOL(inode_permission);
*
* Given a path increment the reference count to the dentry and the vfsmount.
*/
-void path_get(const struct path *path)
+void noinline path_get(const struct path *path)
{
mntget(path->mnt);
dget(path->dentry);
--
2.36.1
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