Am Mittwoch 06 Juli 2011, 00:17:03 schrieben Sie: > On Tue, Jul 5, 2011 at 1:51 PM, Rolf Eike Beer <eike@xxxxxxxxxx> wrote: > > Am Dienstag 05 Juli 2011, 19:28:35 schrieben Sie: > >> On Mon, Jul 4, 2011 at 2:59 PM, Carlos O'Donell > >> <carlos@xxxxxxxxxxxxxxxx> > > > > wrote: > >> > On Mon, Jul 4, 2011 at 2:50 PM, John David Anglin > >> > <dave.anglin@xxxxxxxx> > > > > wrote: > >> >> The Linux man page says the mprotect addr must be a valid pointer or > >> >> a multiple of PAGESIZE. > >> >> It's not clear what the mprotect call is trying to protect but it is > >> >> definitely not page aligned. > >> > > >> > It's trying to protect the new stack for the thread, which is > >> > obviously in the wrong spot. > >> > >> Good news. > >> > >> I have fixed tst-cputimer1. > > > > You also wrote "OK, fixed the kernel." So where an when will these fixes > > show up? > > Unfortunately I hosed my setup and I didn't have git installed to make > a proper diff so here's a diff versus a somewhat recent tree. > > WIP patch: http://www.parisc-linux.org/~carlos/futex.diff Half of your diff (e.g. the int->u32 conversion) is already in upstream. I've rediffed it against Linus tree and fixed some of the whitespace damage. Eike
From 26950303065f2d1d5e36bbb818d3ee8621a6fc2c Mon Sep 17 00:00:00 2001
From: Carlos O'Donell <carlos@xxxxxxxxxxxxxxxx>
Date: Fri, 8 Jul 2011 09:42:31 +0200
Subject: [PATCH] fix futexes
Signed-off-by: Carlos O'Donell <carlos@xxxxxxxxxxxxxxxx>
Signed-off-by: Rolf Eike Beer <eike-kernel@xxxxxxxxx>
---
arch/parisc/include/asm/futex.h | 65 ++++++++++++++++++++++++++++++++++++---
1 files changed, 60 insertions(+), 5 deletions(-)
diff --git a/arch/parisc/include/asm/futex.h b/arch/parisc/include/asm/futex.h
index 67a33cc..3008d06 100644
--- a/arch/parisc/include/asm/futex.h
+++ b/arch/parisc/include/asm/futex.h
@@ -5,11 +5,14 @@
#include <linux/futex.h>
#include <linux/uaccess.h>
+#include <asm/atomic.h>
#include <asm/errno.h>
static inline int
futex_atomic_op_inuser (int encoded_op, u32 __user *uaddr)
{
+ unsigned long int flags;
+ u32 val;
int op = (encoded_op >> 28) & 7;
int cmp = (encoded_op >> 24) & 15;
int oparg = (encoded_op << 8) >> 20;
@@ -23,16 +26,53 @@ futex_atomic_op_inuser (int encoded_op, u32 __user *uaddr)
pagefault_disable();
+ _atomic_spin_lock_irqsave(uaddr, flags);
+
switch (op) {
case FUTEX_OP_SET:
+ /* *(int *)UADDR2 = OPARG; */
+ ret = get_user(oldval, uaddr);
+ if (!ret)
+ ret = put_user(oparg, uaddr);
+ break;
case FUTEX_OP_ADD:
+ /* *(int *)UADDR2 += OPARG; */
+ ret = get_user(oldval, uaddr);
+ if (!ret) {
+ val = oldval + oparg;
+ ret = put_user(val, uaddr);
+ }
+ break;
case FUTEX_OP_OR:
+ /* *(int *)UADDR2 |= OPARG; */
+ ret = get_user(oldval, uaddr);
+ if (!ret) {
+ val = oldval | oparg;
+ ret = put_user(val, uaddr);
+ }
+ break;
case FUTEX_OP_ANDN:
+ /* *(int *)UADDR2 &= ~OPARG; */
+ ret = get_user(oldval, uaddr);
+ if (!ret) {
+ val = oldval & ~oparg;
+ ret = put_user(val, uaddr);
+ }
+ break;
case FUTEX_OP_XOR:
+ /* *(int *)UADDR2 ^= OPARG; */
+ ret = get_user(oldval, uaddr);
+ if (!ret) {
+ val = oldval ^ oparg;
+ ret = put_user(val, uaddr);
+ }
+ break;
default:
ret = -ENOSYS;
}
+ _atomic_spin_unlock_irqrestore(uaddr, flags);
+
pagefault_enable();
if (!ret) {
@@ -54,7 +94,9 @@ static inline int
futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
u32 oldval, u32 newval)
{
+ int ret;
u32 val;
+ unsigned long flags;
/* futex.c wants to do a cmpxchg_inatomic on kernel NULL, which is
* our gateway page, and causes no end of trouble...
@@ -65,12 +107,25 @@ futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32)))
return -EFAULT;
- if (get_user(val, uaddr))
- return -EFAULT;
- if (val == oldval && put_user(newval, uaddr))
- return -EFAULT;
+ /* HPPA has no cmpxchg in hardware and therefore the
+ * best we can do here is use an array of locks. The
+ * lock selected is based on a hash of the userspace
+ * address. This should scale to a couple of CPUs.
+ */
+
+ _atomic_spin_lock_irqsave(uaddr, flags);
+
+ ret = get_user(val, uaddr);
+
+ if (!ret)
+ if (val == oldval)
+ ret = put_user(newval, uaddr);
+
*uval = val;
- return 0;
+
+ _atomic_spin_unlock_irqrestore(uaddr, flags);
+
+ return ret;
}
#endif /*__KERNEL__*/
--
1.7.6
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