On Tue, Jan 28, 2014 at 11:14:19AM +0000, Mark Rutland wrote: > Commit 63d0f0a3c7e1 (mm/readahead.c:do_readhead(): don't check for > ->readpage) unintentionally made do_readahead return 0 for all valid > files regardless of whether readahead was supported, rather than the > expected -EINVAL. This gets forwarded on to userspace, and results in > sys_readahead appearing to succeed in cases that don't make sense (e.g. > when called on pipes or sockets). This issue is detected by the LTP > readahead01 testcase. > > As the exact return value of force_page_cache_readahead is currently > never used, we can simplify it to return only 0 or -EINVAL (when > readpage or readpages is missing). With that in place we can simply > forward on the return value of force_page_cache_readahead in > do_readahead. > > This patch performs said change, restoring the expected semantics. > > Signed-off-by: Mark Rutland <[email protected]> > Cc: Andrew Morton <[email protected]>
Acked-by: Kirill A. Shutemov <[email protected]> -- Kirill A. Shutemov -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/

