From 87243deb88671f70def4c52dfa7ca7830707bd31 Mon Sep 17 00:00:00 2001
From: Seth Forshee <seth.forshee@canonical.com>
Date: Wed, 9 Mar 2016 09:18:07 -0600
Subject: [PATCH 1/3] debugfs: Make automount point inodes permanently empty
Starting with 4.1 the tracing subsystem has its own filesystem
which is automounted in the tracing subdirectory of debugfs.
Prior to this debugfs could be bind mounted in a cloned mount
namespace, but if tracefs has been mounted under debugfs this
now fails because there is a locked child mount. This creates
a regression for container software which bind mounts debugfs
to satisfy the assumption of some userspace software.
In other pseudo filesystems such as proc and sysfs we're already
creating mountpoints like this in such a way that no dirents can
be created in the directories, allowing them to be exceptions to
some MNT_LOCKED tests. In fact we're already do this for the
tracefs mountpoint in sysfs.
Do the same in debugfs_create_automount(), since the intention
here is clearly to create a mountpoint. This fixes the regression,
as locked child mounts on permanently empty directories do not
cause a bind mount to fail.
Cc: stable@vger.kernel.org # v4.1+
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
fs/debugfs/inode.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/fs/debugfs/inode.c b/fs/debugfs/inode.c
index bece948b363d..8580831ed237 100644
--- a/fs/debugfs/inode.c
+++ b/fs/debugfs/inode.c
@@ -457,7 +457,7 @@ struct dentry *debugfs_create_automount(const char *name,
if (unlikely(!inode))
return failed_creating(dentry);
- inode->i_mode = S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO;
+ make_empty_dir_inode(inode);
inode->i_flags |= S_AUTOMOUNT;
inode->i_private = data;
dentry->d_fsdata = (void *)f;
From 3e26a691fe3fe1e02a76e5bab0c143ace4b137b4 Mon Sep 17 00:00:00 2001
From: Rui Salvaterra <rsalvaterra@gmail.com>
Date: Sat, 9 Apr 2016 22:05:34 +0100
Subject: [PATCH 2/3] lib: lz4: fixed zram with lz4 on big endian machines
Based on Sergey's test patch [1], this fixes zram with lz4 compression
on big endian cpus.
Note that the 64-bit preprocessor test is not a cleanup, it's part of
the fix, since those identifiers are bogus (for example, __ppc64__
isn't defined anywhere else in the kernel, which means we'd fall into
the 32-bit definitions on ppc64).
Tested on ppc64 with no regression on x86_64.
[1] http://marc.info/?l=linux-kernel&m=145994470805853&w=4
Cc: stable@vger.kernel.org
Suggested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Rui Salvaterra <rsalvaterra@gmail.com>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
lib/lz4/lz4defs.h | 21 ++++++++++++---------
1 file changed, 12 insertions(+), 9 deletions(-)
diff --git a/lib/lz4/lz4defs.h b/lib/lz4/lz4defs.h
index abcecdc2d0f2..0710a62ad2f6 100644
--- a/lib/lz4/lz4defs.h
+++ b/lib/lz4/lz4defs.h
@@ -11,8 +11,7 @@
/*
* Detects 64 bits mode
*/
-#if (defined(__x86_64__) || defined(__x86_64) || defined(__amd64__) \
- || defined(__ppc64__) || defined(__LP64__))
+#if defined(CONFIG_64BIT)
#define LZ4_ARCH64 1
#else
#define LZ4_ARCH64 0
@@ -35,6 +34,10 @@ typedef struct _U64_S { u64 v; } U64_S;
#define PUT4(s, d) (A32(d) = A32(s))
#define PUT8(s, d) (A64(d) = A64(s))
+
+#define LZ4_READ_LITTLEENDIAN_16(d, s, p) \
+ (d = s - A16(p))
+
#define LZ4_WRITE_LITTLEENDIAN_16(p, v) \
do { \
A16(p) = v; \
@@ -51,10 +54,13 @@ typedef struct _U64_S { u64 v; } U64_S;
#define PUT8(s, d) \
put_unaligned(get_unaligned((const u64 *) s), (u64 *) d)
-#define LZ4_WRITE_LITTLEENDIAN_16(p, v) \
- do { \
- put_unaligned(v, (u16 *)(p)); \
- p += 2; \
+#define LZ4_READ_LITTLEENDIAN_16(d, s, p) \
+ (d = s - get_unaligned_le16(p))
+
+#define LZ4_WRITE_LITTLEENDIAN_16(p, v) \
+ do { \
+ put_unaligned_le16(v, (u16 *)(p)); \
+ p += 2; \
} while (0)
#endif
@@ -140,9 +146,6 @@ typedef struct _U64_S { u64 v; } U64_S;
#endif
-#define LZ4_READ_LITTLEENDIAN_16(d, s, p) \
- (d = s - get_unaligned_le16(p))
-
#define LZ4_WILDCOPY(s, d, e) \
do { \
LZ4_COPYPACKET(s, d); \
From dea5c24a14047b7d6b6b269434a85ffd05f1d2cb Mon Sep 17 00:00:00 2001
From: Rui Salvaterra <rsalvaterra@gmail.com>
Date: Sat, 9 Apr 2016 22:05:35 +0100
Subject: [PATCH 3/3] lib: lz4: cleanup unaligned access efficiency detection
These identifiers are bogus. The interested architectures should define
HAVE_EFFICIENT_UNALIGNED_ACCESS whenever relevant to do so. If this
isn't true for some arch, it should be fixed in the arch definition.
Signed-off-by: Rui Salvaterra <rsalvaterra@gmail.com>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
lib/lz4/lz4defs.h | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)
diff --git a/lib/lz4/lz4defs.h b/lib/lz4/lz4defs.h
index 0710a62ad2f6..c79d7ea8a38e 100644
--- a/lib/lz4/lz4defs.h
+++ b/lib/lz4/lz4defs.h
@@ -24,9 +24,7 @@
typedef struct _U16_S { u16 v; } U16_S;
typedef struct _U32_S { u32 v; } U32_S;
typedef struct _U64_S { u64 v; } U64_S;
-#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) \
- || defined(CONFIG_ARM) && __LINUX_ARM_ARCH__ >= 6 \
- && defined(ARM_EFFICIENT_UNALIGNED_ACCESS)
+#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
#define A16(x) (((U16_S *)(x))->v)
#define A32(x) (((U32_S *)(x))->v)