diff mbox series

[RFC,22/22] riscv: s64ilp32: Temporary workaround solution to gcc problem

Message ID 20230518131013.3366406-23-guoren@kernel.org (mailing list archive)
State Not Applicable
Headers show
Series riscv: s64ilp32: Running 32-bit Linux kernel on 64-bit supervisor mode | expand

Checks

Context Check Description
conchuod/tree_selection fail Failed to apply to next/pending-fixes, riscv/for-next or riscv/master

Commit Message

Guo Ren May 18, 2023, 1:10 p.m. UTC 
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 mbox series

Patch

diff --git a/fs/namei.c b/fs/namei.c
index edfedfbccaef..22a2ef77e074 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -541,7 +541,7 @@  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);