From fad1a86e25e0a1f85635ed06ef62ddadd5b8fa4c Mon Sep 17 00:00:00 2001 From: HATAYAMA Daisuke Date: Wed, 16 Oct 2013 13:47:05 -0700 Subject: [PATCH] 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 Signed-off-by: HATAYAMA Daisuke Cc: Alexey Dobriyan Cc: David S. Miller Tested-by: Michael Holzheu Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/proc/inode.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/fs/proc/inode.c b/fs/proc/inode.c index 6c501c4d996d..8eaa1ba793fc 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; +#endif + 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); unuse_pde(pde); -- 2.20.1