Re: [PATCH 1/2] Extend sys_clone and sys_unshare system calls API

2008-01-24 Thread Pavel Machek
On Thu 2008-01-24 09:46:57, Dave Hansen wrote: > On Thu, 2008-01-24 at 18:37 +0100, Pavel Machek wrote: > > > Did we decide not to do something with a variable number of > > arguments? > > > > > > sys_clonefoo(unsigned long *flags, int len); > > > > That is evil, because that means strace c

Re: [PATCH 1/2] Extend sys_clone and sys_unshare system calls API

2008-01-24 Thread Dave Hansen
On Thu, 2008-01-24 at 18:37 +0100, Pavel Machek wrote: > > Did we decide not to do something with a variable number of > arguments? > > > > sys_clonefoo(unsigned long *flags, int len); > > That is evil, because that means strace can no longer reliably print > flags being used (for example).

Re: [PATCH 1/2] Extend sys_clone and sys_unshare system calls API

2008-01-24 Thread Pavel Machek
On Thu 2008-01-24 09:24:34, Dave Hansen wrote: > On Thu, 2008-01-24 at 18:09 +0100, Cedric Le Goater wrote: > > yes but we would need more something like : > > > > long sys_clone64(unsigned long flags_high, unsigned long flag_low) > > > > if we want the syscall to be supported on 32bit arch. c

Re: [PATCH 1/2] Extend sys_clone and sys_unshare system calls API

2008-01-24 Thread Dave Hansen
On Thu, 2008-01-24 at 18:09 +0100, Cedric Le Goater wrote: > yes but we would need more something like : > > long sys_clone64(unsigned long flags_high, unsigned long flag_low) > > if we want the syscall to be supported on 32bit arch. clone2 is also > being used on ia64 already. Did we decide

Re: [PATCH 1/2] Extend sys_clone and sys_unshare system calls API

2008-01-24 Thread Cedric Le Goater
Pavel Machek wrote: > On Wed 2008-01-16 15:58:55, Pavel Emelyanov wrote: >> There's only one bit in the clone_flags left, so we won't be able >> to create more namespaces after we make it busy. Besides, for >> checkpoint/restart jobs we might want to create tasks with given >> pids (virtual of co

Re: [PATCH 1/2] Extend sys_clone and sys_unshare system calls API

2008-01-24 Thread Pavel Machek
On Wed 2008-01-16 15:58:55, Pavel Emelyanov wrote: > There's only one bit in the clone_flags left, so we won't be able > to create more namespaces after we make it busy. Besides, for > checkpoint/restart jobs we might want to create tasks with given > pids (virtual of course). And nobody knows fo

Extending syscalls (was: [PATCH 1/2] Extend sys_clone and sys_unshare system calls API)

2008-01-17 Thread Jonathan Corbet
Al Viro sez: > Nah, just put an XML parser into the kernel to have the form match the > contents... > > Al "perhaps we should newgroup alt.tasteless.api for all that stuff" Viro Heh, indeed. But we do seem to have a recurring problem of people wanting to extend sys_foo() beyond the confines of

Re: [PATCH 1/2] Extend sys_clone and sys_unshare system calls API

2008-01-17 Thread Cedric Le Goater
Al Viro wrote: > On Wed, Jan 16, 2008 at 07:23:40AM -0700, Jonathan Corbet wrote: >> Hi, Pavel, >> >> [Adding Ulrich] >> >>> I use the last bit in the clone_flags for CLONE_LONGARG. When set it >>> will denote that the child_tidptr is not a pointer to a tid storage, >>> but the pointer to the struc

Re: [PATCH 1/2] Extend sys_clone and sys_unshare system calls API

2008-01-16 Thread Al Viro
On Wed, Jan 16, 2008 at 07:23:40AM -0700, Jonathan Corbet wrote: > Hi, Pavel, > > [Adding Ulrich] > > > I use the last bit in the clone_flags for CLONE_LONGARG. When set it > > will denote that the child_tidptr is not a pointer to a tid storage, > > but the pointer to the struct long_clone_struct

Re: [PATCH 1/2] Extend sys_clone and sys_unshare system calls API

2008-01-16 Thread Pavel Emelyanov
Jonathan Corbet wrote: > Hi, Pavel, > > [Adding Ulrich] > >> I use the last bit in the clone_flags for CLONE_LONGARG. When set it >> will denote that the child_tidptr is not a pointer to a tid storage, >> but the pointer to the struct long_clone_struct which currently >> looks like this: > > I'

Re: [PATCH 1/2] Extend sys_clone and sys_unshare system calls API

2008-01-16 Thread Jonathan Corbet
Hi, Pavel, [Adding Ulrich] > I use the last bit in the clone_flags for CLONE_LONGARG. When set it > will denote that the child_tidptr is not a pointer to a tid storage, > but the pointer to the struct long_clone_struct which currently > looks like this: I'm probably just totally off the deep en

[PATCH 1/2] Extend sys_clone and sys_unshare system calls API

2008-01-16 Thread Pavel Emelyanov
There's only one bit in the clone_flags left, so we won't be able to create more namespaces after we make it busy. Besides, for checkpoint/restart jobs we might want to create tasks with given pids (virtual of course). And nobody knows for sure what else might be required from clone() in the fut