diff options
authorHATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>2013-10-16 13:47:05 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2013-10-16 21:35:53 -0700
commitfad1a86e25e0a1f85635ed06ef62ddadd5b8fa4c (patch)
parent2cbe3b0af82279f14cfb3195f2406651f28ee9b8 (diff)
procfs: call default get_unmapped_area on MMU-present architectures
Commit c4fe24485729 ("sparc: fix PCI device proc file mmap(2)") added proc_reg_get_unmapped_area in proc_reg_file_ops and proc_reg_file_ops_no_compat, by which now mmap always returns EIO if get_unmapped_area method is not defined for the target procfs file, which causes regression of mmap on /proc/vmcore. To address this issue, like get_unmapped_area(), call default current->mm->get_unmapped_area on MMU-present architectures if pde->proc_fops->get_unmapped_area, i.e. the one in actual file operation in the procfs file, is not defined. Reported-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: David S. Miller <davem@davemloft.net> Tested-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 files changed, 6 insertions, 2 deletions
diff --git a/fs/proc/inode.c b/fs/proc/inode.c
index 6c501c4d996..8eaa1ba793f 100644
--- a/fs/proc/inode.c
+++ b/fs/proc/inode.c
@@ -289,9 +289,13 @@ static unsigned long proc_reg_get_unmapped_area(struct file *file, unsigned long
struct proc_dir_entry *pde = PDE(file_inode(file));
unsigned long rv = -EIO;
- unsigned long (*get_unmapped_area)(struct file *, unsigned long, unsigned long, unsigned long, unsigned long);
+ unsigned long (*get_unmapped_area)(struct file *, unsigned long, unsigned long, unsigned long, unsigned long) = NULL;
if (use_pde(pde)) {
- get_unmapped_area = pde->proc_fops->get_unmapped_area;
+#ifdef CONFIG_MMU
+ get_unmapped_area = current->mm->get_unmapped_area;
+ if (pde->proc_fops->get_unmapped_area)
+ get_unmapped_area = pde->proc_fops->get_unmapped_area;
if (get_unmapped_area)
rv = get_unmapped_area(file, orig_addr, len, pgoff, flags);