Re: [3/3] use vmalloc() to arrange guard pages for stacks

2007-05-01 Thread Bill Irwin
Bill Irwin wrote: >> It's a shame that the resource scalability implications of vmallocspace >> allocations prevent this from being useful in production. One could, in >> principle, establish guard pages within ZONE_NORMAL, but for 4KB stacks >> it's somewhat awkward to dredge up 3 contigous

Re: [3/3] use vmalloc() to arrange guard pages for stacks

2007-05-01 Thread Chuck Ebbert
Bill Irwin wrote: > > It's a shame that the resource scalability implications of vmallocspace > allocations prevent this from being useful in production. One could, in > principle, establish guard pages within ZONE_NORMAL, but for 4KB stacks > it's somewhat awkward to dredge up 3 contigous pages,

Re: [3/3] use vmalloc() to arrange guard pages for stacks

2007-05-01 Thread Bill Irwin
Bill Irwin wrote: >> This patch introduces CONFIG_DEBUG_STACK, which vmalloc()'s task and IRQ >> stacks in order to establish guard pages. In such a manner any stack >> overflow that references pages immediately adjacent to the stack is >> immediately trapped with a fault, which precludes silent

Re: [3/3] use vmalloc() to arrange guard pages for stacks

2007-05-01 Thread Chuck Ebbert
Bill Irwin wrote: > This patch introduces CONFIG_DEBUG_STACK, which vmalloc()'s task and IRQ > stacks in order to establish guard pages. In such a manner any stack > overflow that references pages immediately adjacent to the stack is > immediately trapped with a fault, which precludes silent

Re: [3/3] use vmalloc() to arrange guard pages for stacks

2007-05-01 Thread Chuck Ebbert
Bill Irwin wrote: This patch introduces CONFIG_DEBUG_STACK, which vmalloc()'s task and IRQ stacks in order to establish guard pages. In such a manner any stack overflow that references pages immediately adjacent to the stack is immediately trapped with a fault, which precludes silent memory

Re: [3/3] use vmalloc() to arrange guard pages for stacks

2007-05-01 Thread Bill Irwin
Bill Irwin wrote: This patch introduces CONFIG_DEBUG_STACK, which vmalloc()'s task and IRQ stacks in order to establish guard pages. In such a manner any stack overflow that references pages immediately adjacent to the stack is immediately trapped with a fault, which precludes silent memory

Re: [3/3] use vmalloc() to arrange guard pages for stacks

2007-05-01 Thread Chuck Ebbert
Bill Irwin wrote: It's a shame that the resource scalability implications of vmallocspace allocations prevent this from being useful in production. One could, in principle, establish guard pages within ZONE_NORMAL, but for 4KB stacks it's somewhat awkward to dredge up 3 contigous pages, and

Re: [3/3] use vmalloc() to arrange guard pages for stacks

2007-05-01 Thread Bill Irwin
Bill Irwin wrote: It's a shame that the resource scalability implications of vmallocspace allocations prevent this from being useful in production. One could, in principle, establish guard pages within ZONE_NORMAL, but for 4KB stacks it's somewhat awkward to dredge up 3 contigous pages, and 4

[3/3] use vmalloc() to arrange guard pages for stacks

2007-04-30 Thread Bill Irwin
This patch introduces CONFIG_DEBUG_STACK, which vmalloc()'s task and IRQ stacks in order to establish guard pages. In such a manner any stack overflow that references pages immediately adjacent to the stack is immediately trapped with a fault, which precludes silent memory corruption or

[3/3] use vmalloc() to arrange guard pages for stacks

2007-04-30 Thread Bill Irwin
This patch introduces CONFIG_DEBUG_STACK, which vmalloc()'s task and IRQ stacks in order to establish guard pages. In such a manner any stack overflow that references pages immediately adjacent to the stack is immediately trapped with a fault, which precludes silent memory corruption or