x86_64: fix 2.6.18 regression - PTRACE_OLDSETOPTIONS should be accepted

x86_64: fix 2.6.18 regression - PTRACE_OLDSETOPTIONS should be accepted

[Paolo 'Blaisorblade' Giarrusso]

Also PTRACE_OLDSETOPTIONS should be accepted, as done by kernel/ptrace.c and
forced by binary compatibility. UML/32bit breaks because of this - since it is wise
enough to use PTRACE_OLDSETOPTIONS to be binary compatible with 2.4 host
kernels.

Until 2.6.17 (commit f0f2d6536e3515b5b1b7ae97dc8f176860c8c2ce) we had:

       default:
                return sys_ptrace(request, pid, addr, data);

Instead here we have:
        case PTRACE_GET_THREAD_AREA:
	case ...:
                return sys_ptrace(request, pid, addr, data);

        default:
                return -EINVAL;

This change was a style change - when a case is added, it must be explicitly
tested this way. In this case, not enough testing was done.

Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Index: linux-2.6.git/arch/x86_64/ia32/ptrace32.c
===================================================================
--- linux-2.6.git.orig/arch/x86_64/ia32/ptrace32.c
+++ linux-2.6.git/arch/x86_64/ia32/ptrace32.c
@@ -246,6 +246,7 @@ asmlinkage long sys32_ptrace(long reques
 	case PTRACE_SINGLESTEP:
 	case PTRACE_DETACH:
 	case PTRACE_SYSCALL:
+	case PTRACE_OLDSETOPTIONS:
 	case PTRACE_SETOPTIONS:
 	case PTRACE_SET_THREAD_AREA:
 	case PTRACE_GET_THREAD_AREA:

Re: x86_64: fix 2.6.18 regression - PTRACE_OLDSETOPTIONS should be accepted

[Jeff Dike]

On Thu, Feb 15, 2007 at 03:34:23AM +0100, Paolo 'Blaisorblade' Giarrusso wrote:
> Index: linux-2.6.git/arch/x86_64/ia32/ptrace32.c
> ===================================================================
> --- linux-2.6.git.orig/arch/x86_64/ia32/ptrace32.c
> +++ linux-2.6.git/arch/x86_64/ia32/ptrace32.c
> @@ -246,6 +246,7 @@ asmlinkage long sys32_ptrace(long reques
>  	case PTRACE_SINGLESTEP:
>  	case PTRACE_DETACH:
>  	case PTRACE_SYSCALL:
> +	case PTRACE_OLDSETOPTIONS:
>  	case PTRACE_SETOPTIONS:
>  	case PTRACE_SET_THREAD_AREA:
>  	case PTRACE_GET_THREAD_AREA:
> 

I sent an equivalent patch in earlier today:

Index: linux-2.6/arch/x86_64/ia32/ptrace32.c
===================================================================
--- linux-2.6.orig/arch/x86_64/ia32/ptrace32.c
+++ linux-2.6/arch/x86_64/ia32/ptrace32.c
@@ -239,6 +239,8 @@ asmlinkage long sys32_ptrace(long reques
 	__u32 val;
 
 	switch (request) { 
+	case PTRACE_OLDSETOPTIONS:
+		request = PTRACE_SETOPTIONS;
 	case PTRACE_TRACEME:
 	case PTRACE_ATTACH:
 	case PTRACE_KILL:

I change the request so that PTRACE_OLDSETOPTIONS doesn't need to
propogate any further.  However, it is present in include/asm-x86_64,
so I guess that counts as being part of the x86_64 ABI.  That being
the case, I guess my patch can be dropped in favor of this one.

				Jeff

-- 
Work email - jdike at linux dot intel dot com

Re: [uml-devel] x86_64: fix 2.6.18 regression - PTRACE_OLDSETOPTIONS should be accepted

[Blaisorblade]

On Thursday 15 February 2007 03:54, Jeff Dike wrote:
> On Thu, Feb 15, 2007 at 03:34:23AM +0100, Paolo 'Blaisorblade' Giarrusso 
wrote:
> > Index: linux-2.6.git/arch/x86_64/ia32/ptrace32.c
> > ===================================================================
> > --- linux-2.6.git.orig/arch/x86_64/ia32/ptrace32.c
> > +++ linux-2.6.git/arch/x86_64/ia32/ptrace32.c
> > @@ -246,6 +246,7 @@ asmlinkage long sys32_ptrace(long reques
> >  	case PTRACE_SINGLESTEP:
> >  	case PTRACE_DETACH:
> >  	case PTRACE_SYSCALL:
> > +	case PTRACE_OLDSETOPTIONS:
> >  	case PTRACE_SETOPTIONS:
> >  	case PTRACE_SET_THREAD_AREA:
> >  	case PTRACE_GET_THREAD_AREA:
>
> I sent an equivalent patch in earlier today:
Doh! Interesting this timing...

> Index: linux-2.6/arch/x86_64/ia32/ptrace32.c
> ===================================================================
> --- linux-2.6.orig/arch/x86_64/ia32/ptrace32.c
> +++ linux-2.6/arch/x86_64/ia32/ptrace32.c
> @@ -239,6 +239,8 @@ asmlinkage long sys32_ptrace(long reques
>  	__u32 val;
>
>  	switch (request) {
> +	case PTRACE_OLDSETOPTIONS:
> +		request = PTRACE_SETOPTIONS;
>  	case PTRACE_TRACEME:
>  	case PTRACE_ATTACH:
>  	case PTRACE_KILL:
>
> I change the request so that PTRACE_OLDSETOPTIONS doesn't need to
> propogate any further.  However, it is present in include/asm-x86_64,
> so I guess that counts as being part of the x86_64 ABI.  That being
> the case, I guess my patch can be dropped in favor of this one.

It is handled in ptrace_request, unless there are include problems. I'm going 
to reboot and test mine for any remaining problem.
-- 
Inform me of my mistakes, so I can add them to my list!
Paolo Giarrusso, aka Blaisorblade
http://www.user-mode-linux.org/~blaisorblade
Chiacchiera con i tuoi amici in tempo reale! 
 http://it.yahoo.com/mail_it/foot/*http://it.messenger.yahoo.com 

Re: [uml-devel] x86_64: fix 2.6.18 regression - PTRACE_OLDSETOPTIONS should be accepted

[Andrew Morton]

On Thu, 15 Feb 2007 04:43:41 +0100 Blaisorblade <blaisorblade@yahoo.it> wrote:

> > I sent an equivalent patch in earlier today:
> Doh! Interesting this timing...
> 
> > Index: linux-2.6/arch/x86_64/ia32/ptrace32.c
> > ===================================================================
> > --- linux-2.6.orig/arch/x86_64/ia32/ptrace32.c
> > +++ linux-2.6/arch/x86_64/ia32/ptrace32.c
> > @@ -239,6 +239,8 @@ asmlinkage long sys32_ptrace(long reques
> >  	__u32 val;
> >
> >  	switch (request) {
> > +	case PTRACE_OLDSETOPTIONS:
> > +		request = PTRACE_SETOPTIONS;
> >  	case PTRACE_TRACEME:
> >  	case PTRACE_ATTACH:
> >  	case PTRACE_KILL:
> >
> > I change the request so that PTRACE_OLDSETOPTIONS doesn't need to
> > propogate any further.  However, it is present in include/asm-x86_64,
> > so I guess that counts as being part of the x86_64 ABI.  That being
> > the case, I guess my patch can be dropped in favor of this one.
> 
> It is handled in ptrace_request, unless there are include problems. I'm going 
> to reboot and test mine for any remaining problem.

Whatever happens, please ensure that the final fix makes it into -stable
as well.  Jeff's version of this patch wasn't cc'ed to stable@kernel.org.

Re: [uml-devel] x86_64: fix 2.6.18 regression - PTRACE_OLDSETOPTIONS should be accepted

[Jeff Dike]

On Wed, Feb 14, 2007 at 09:51:23PM -0800, Andrew Morton wrote:
> Whatever happens, please ensure that the final fix makes it into -stable
> as well.  Jeff's version of this patch wasn't cc'ed to stable@kernel.org.

Paolo's patch was sent to -stable.  His should be used everywhere, and mine
should be dropped.

				Jeff

-- 
Work email - jdike at linux dot intel dot com

Re: [uml-devel] x86_64: fix 2.6.18 regression - PTRACE_OLDSETOPTIONS should be accepted

[Blaisorblade]

On Thursday 15 February 2007 18:01, Jeff Dike wrote:
> On Wed, Feb 14, 2007 at 09:51:23PM -0800, Andrew Morton wrote:
> > Whatever happens, please ensure that the final fix makes it into -stable
> > as well.  Jeff's version of this patch wasn't cc'ed to stable@kernel.org.
>
> Paolo's patch was sent to -stable.  His should be used everywhere, and mine
> should be dropped.

Jeff, I verified my patch is _almost_ enough for 2.6.18 for fully booting a 
32bit UML; on 2.6.18 I had to also add PTRACE_GET/SET_THREAD_AREA (this fix 
was merged in 2.6.19) to avoid tons of TLS errors.

On 2.6.19, the crash at boot is removed (btw, that crash output no message - I 
hope that with your fatal/nonfatal/etc. introduction I would get a message) 
but another one happens when starting init. I'll test 2.6.20 ASAP.

Bye
-- 
Inform me of my mistakes, so I can add them to my list!
Paolo Giarrusso, aka Blaisorblade
http://www.user-mode-linux.org/~blaisorblade

Chiacchiera con i tuoi amici in tempo reale! 
 http://it.yahoo.com/mail_it/foot/*http://it.messenger.yahoo.com 

Re: [uml-devel] x86_64: fix 2.6.18 regression - PTRACE_OLDSETOPTIONS should be accepted

[Jeff Dike]

On Thu, Feb 15, 2007 at 08:05:56PM +0100, Blaisorblade wrote:
> Jeff, I verified my patch is _almost_ enough for 2.6.18 for fully booting a 
> 32bit UML; on 2.6.18 I had to also add PTRACE_GET/SET_THREAD_AREA (this fix 
> was merged in 2.6.19) to avoid tons of TLS errors.

I'm not seeing that.  With the current set of patches, I have 32-bit UMLs
happily booting on x86_64.

				Jeff

-- 
Work email - jdike at linux dot intel dot com

Re: [uml-devel] x86_64: fix 2.6.18 regression - PTRACE_OLDSETOPTIONS should be accepted

[Blaisorblade]

On Friday 16 February 2007 20:02, Jeff Dike wrote:
> On Thu, Feb 15, 2007 at 08:05:56PM +0100, Blaisorblade wrote:
> > Jeff, I verified my patch is _almost_ enough for 2.6.18 for fully booting
> > a 32bit UML; on 2.6.18 I had to also add PTRACE_GET/SET_THREAD_AREA (this
> > fix was merged in 2.6.19) to avoid tons of TLS errors.
>
> I'm not seeing that.  With the current set of patches, I have 32-bit UMLs
> happily booting on x86_64.
Which kernel? I've not yet tested 2.6.20. I'll try debugging this 
subsequently.
-- 
Inform me of my mistakes, so I can add them to my list!
Paolo Giarrusso, aka Blaisorblade
http://www.user-mode-linux.org/~blaisorblade
Chiacchiera con i tuoi amici in tempo reale! 
 http://it.yahoo.com/mail_it/foot/*http://it.messenger.yahoo.com 

Re: [uml-devel] x86_64: fix 2.6.18 regression - PTRACE_OLDSETOPTIONS should be accepted

[Jeff Dike]

On Sat, Feb 17, 2007 at 01:04:35AM +0100, Blaisorblade wrote:
> Which kernel? I've not yet tested 2.6.20. I'll try debugging this 
> subsequently.

2.6.20-rc6-mm3 on 2.6.20 + patches works for me.

					Jeff

-- 
Work email - jdike at linux dot intel dot com