[PATCH] Get core dump code to work...

The file based core dump code was broken by pipe changes - a relative
llseek returns the absolute file position on success, not the relative
one, so dump_seek() always failed when invoked with non-zero current
position.

Only success/failure can be tested with relative lseek, we have to trust
kernel that on success we've got right file offset.  With this fix in
place I have finally real core files instead of 1KB fragments...

Signed-off-by: Petr Vandrovec <petr@vandrovec.name>
[ Cleaned it up a bit while here - use SEEK_CUR instead of hardcoding 1 ]
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c
index 06435f3..5610061 100644 (file)
--- a/fs/binfmt_elf.c
+++ b/fs/binfmt_elf.c
@@ -1152,7 +1152,7 @@ static int dump_write(struct file *file, const void *addr, int nr)
 static int dump_seek(struct file *file, loff_t off)
 {
        if (file->f_op->llseek && file->f_op->llseek != no_llseek) {
-               if (file->f_op->llseek(file, off, 1) != off)
+               if (file->f_op->llseek(file, off, SEEK_CUR) < 0)
                        return 0;
        } else {
                char *buf = (char *)get_zeroed_page(GFP_KERNEL);