[PATCH] kexec/fs2dt: fix endianess conversion

Laurent Dufour
2013-10-15T17:07:14Z

While reviewing fs2dt.c in the common kexec directory, in order to use it to
support little endian ppc64 architecture, I found some endianess
conversion's issues.

In dt_reserve, dt_base is a pointer and thus should not be converted.

In checkprop, values read from the device tree are big endian encoded and
should be converted if CPU is running in little endian mode.

In add_dyn_reconf_usable_mem_property__, fix extraneous endianess conversion
of rlen which should be natively used to increase the dt pointer.

Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com>
---
kexec/fs2dt.c | 19 +++++++++++--------
1 file changed, 11 insertions(+), 8 deletions(-)

diff --git a/kexec/fs2dt.c b/kexec/fs2dt.c
index 242a15e..5d774ae 100644
--- a/kexec/fs2dt.c
+++ b/kexec/fs2dt.c
@@ -84,7 +84,7 @@ static void dt_reserve(unsigned **dt_ptr, unsigned words)
offset = *dt_ptr - dt_base;
dt_base = new_dt;
dt_cur_size = new_size;
- *dt_ptr = cpu_to_be32((unsigned)dt_base + offset);
+ *dt_ptr = dt_base + offset;
memset(*dt_ptr, 0, (new_size - offset)*4);
}
}
@@ -112,19 +112,22 @@ static void checkprop(char *name, unsigned *data, int len)
if ((data == NULL) && (base || size || end))
die("unrecoverable error: no property data");
else if (!strcmp(name, "linux,rtas-base"))
- base = *data;
+ base = be32_to_cpu(*data);
else if (!strcmp(name, "linux,tce-base"))
- base = *(unsigned long long *) data;
+ base = be64_to_cpu(*(unsigned long long *) data);
else if (!strcmp(name, "rtas-size") ||
!strcmp(name, "linux,tce-size"))
- size = *data;
+ size = be32_to_cpu(*data);
else if (reuse_initrd && !strcmp(name, "linux,initrd-start"))
if (len == 8)
- base = *(unsigned long long *) data;
+ base = be64_to_cpu(*(unsigned long long *) data);
else
- base = *data;
+ base = be32_to_cpu(*data);
else if (reuse_initrd && !strcmp(name, "linux,initrd-end"))
- end = *(unsigned long long *) data;
+ if (len == 8)
+ end = be64_to_cpu(*(unsigned long long *) data);
+ else
+ end = be32_to_cpu(*data);

if (size && end)
die("unrecoverable error: size and end set at same time\n");
@@ -267,7 +270,7 @@ static void add_dyn_reconf_usable_mem_property__(int fd)
pad_structure_block(rlen);
memcpy(dt, ranges, rlen);
free(ranges);
- dt += cpu_to_be32((rlen + 3)/4);
+ dt += (rlen + 3)/4;
}

static void add_dyn_reconf_usable_mem_property(struct dirent *dp, int fd)