On Saturday 09 July 2005 13:07, Russell King wrote: > On Sat, Jul 09, 2005 at 01:01:33PM +0200, [EMAIL PROTECTED] wrote: > > diff -puN arch/um/sys-x86_64/signal.c~uml-fix-for-gcc4-lvalue > > arch/um/sys-x86_64/signal.c --- > > linux-2.6.git/arch/um/sys-x86_64/signal.c~uml-fix-for-gcc4-lvalue 2005-07 > >-09 13:01:03.000000000 +0200 +++ > > linux-2.6.git-paolo/arch/um/sys-x86_64/signal.c 2005-07-09 > > 13:01:03.000000000 +0200 @@ -168,7 +168,7 @@ int > > setup_signal_stack_si(unsigned long > > > > frame = (struct rt_sigframe __user *) > > round_down(stack_top - sizeof(struct rt_sigframe), 16) - 8; > > - ((unsigned char *) frame) -= 128; > > + frame -= 128 / sizeof(frame); > > Are you sure these two are identical? SOOOOOOOOORRY, I've become crazy, I meant sizeof(*frame)... thanks for noticing.
> The above code fragment looks suspicious anyway, particularly: > > frame = (struct rt_sigframe __user *) > round_down(stack_top - sizeof(struct rt_sigframe), 16) - 8; > > which will put the frame at 8 * sizeof(struct rt_sigframe) below > the point which round_down() would return (which would be 1 struct > rt_sigframe below stack_top, rounded down). You're completely right. The code is copied from arch/x86_64/kernel/signal.c:setup_rt_frame(), so it should make some sense; but in the source, the cast is to (void*). Surely Jeff, seeing that the result is assigned to a struct rt_sigframe __user, "fixed" it. The line I'm patching is new from Jeff, and I don't know what's about (I just remember that Also, the below access_ok() called on fp (which is still NULL) is surely completely wrong, though it won't fail (after all, NULL is under TASK_SIZE. right?). On x86_64 the code is always used from arch/um/kernel/signal_kern.c, since CONFIG_whatever is not enabled. -- Inform me of my mistakes, so I can keep imitating Homer Simpson's "Doh!". Paolo Giarrusso, aka Blaisorblade (Skype ID "PaoloGiarrusso", ICQ 215621894) http://www.user-mode-linux.org/~blaisorblade ___________________________________ Yahoo! Mail: gratis 1GB per i messaggi e allegati da 10MB http://mail.yahoo.it - 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/
