[PATCH] Fix regression added by ppoll/pselect code.
authorDavid S. Miller <davem@davemloft.net>
Fri, 20 Jan 2006 00:40:42 +0000 (16:40 -0800)
committerLinus Torvalds <torvalds@g5.osdl.org>
Fri, 20 Jan 2006 06:11:31 +0000 (22:11 -0800)
The compat layer timeout handling changes in:

9f72949f679df06021c9e43886c9191494fdb007

are busted.  This is most easily seen with an X application
that uses sub-second select/poll timeout such as emacs.  You
hit a key and it takes a second or so before the app responds.

The two ROUND_UP() calls upon entry are using {tv,ts}_sec where it
should instead be using {tv_usec,ts_nsec}, which perfectly explains
the observed incorrect behavior.

Another bug shot down with git bisect.

Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
fs/compat.c

index 18b21b4c9e3a55ca70f0b2f939137483c24ed22c..ff0bafcff7204ac1dc24204ef0c3a47f919eed6c 100644 (file)
@@ -1743,7 +1743,7 @@ asmlinkage long compat_sys_select(int n, compat_ulong_t __user *inp,
                if ((u64)tv.tv_sec >= (u64)MAX_INT64_SECONDS)
                        timeout = -1;   /* infinite */
                else {
-                       timeout = ROUND_UP(tv.tv_sec, 1000000/HZ);
+                       timeout = ROUND_UP(tv.tv_usec, 1000000/HZ);
                        timeout += tv.tv_sec * HZ;
                }
        }
@@ -1884,7 +1884,7 @@ asmlinkage long compat_sys_ppoll(struct pollfd __user *ufds,
                /* We assume that ts.tv_sec is always lower than
                   the number of seconds that can be expressed in
                   an s64. Otherwise the compiler bitches at us */
-               timeout = ROUND_UP(ts.tv_sec, 1000000000/HZ);
+               timeout = ROUND_UP(ts.tv_nsec, 1000000000/HZ);
                timeout += ts.tv_sec * HZ;
        }