On 2019-10-13 01:18, Joerg Sonnenberger wrote:
On Sun, Oct 13, 2019 at 12:46:24AM +0200, Johnny Billquist wrote:
But if you use alloca(), you will have to check what size you'd like to
allocate, and not allocate more than some maximum amount, I would assume. Or
do you really think that it is ok
On Sun, Oct 13, 2019 at 12:46:24AM +0200, Johnny Billquist wrote:
> On 2019-10-12 20:47, Joerg Sonnenberger wrote:
> > On Sat, Oct 12, 2019 at 08:13:25PM +0200, Johnny Billquist wrote:
> > > On 2019-10-12 19:01, Emmanuel Dreyfus wrote:
> > > > Mouse wrote:
> > > >
> > > > > I'm presumably
jo...@bec.de (Joerg Sonnenberger) writes:
>> Even if it comes from the bootloader, why would you want to use alloca()?
>Because as Emmanuel wrote initially, dynamic allocations might not be
>possible yet.
More so than dynamic stack expansion.
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Michael van
On 2019-10-12 20:47, Joerg Sonnenberger wrote:
On Sat, Oct 12, 2019 at 08:13:25PM +0200, Johnny Billquist wrote:
On 2019-10-12 19:01, Emmanuel Dreyfus wrote:
Mouse wrote:
I'm presumably missing something here, but what?
I suspect Maxime's concern is about uncontrolled stack-based variable
On Sat, Oct 12, 2019 at 02:01:16AM +0200, Emmanuel Dreyfus wrote:
> I recently encountered a situation where I had to deal with variable
> length structure at a time where kernel dynamic allocator was not
> initialized.
You can borrow pages directly if the data is potentially larger.
Joerg
On Sat, Oct 12, 2019 at 08:13:25PM +0200, Johnny Billquist wrote:
> On 2019-10-12 19:01, Emmanuel Dreyfus wrote:
> > Mouse wrote:
> >
> > > I'm presumably missing something here, but what?
> >
> > I suspect Maxime's concern is about uncontrolled stack-based variable
> > buffer, which could be
On 2019-10-12 19:01, Emmanuel Dreyfus wrote:
Mouse wrote:
I'm presumably missing something here, but what?
I suspect Maxime's concern is about uncontrolled stack-based variable
buffer, which could be used to crash the kernel.
But in my case, the data is coming from the bootloader. I cannot
Mouse wrote:
> I'm presumably missing something here, but what?
I suspect Maxime's concern is about uncontrolled stack-based variable
buffer, which could be used to crash the kernel.
But in my case, the data is coming from the bootloader. I cannot think
about a scenario where it makes sense to
>> [...alloca() in kernel code...]
> The kernel stack is rather small, we should not start allocating
> variable-sized stuff on it.
You say that as though the part after the comma follows from the part
before it. If so, I don't understand why. The alternative seems to me
to be to allocate a
