From: Wei Liu <wei.liu@xxxxxxxxxx> Sent: Monday, July 12, 2021 11:24 AM
>
> On Sun, Jul 11, 2021 at 08:25:14PM -0700, Michael Kelley wrote:
> [...]
> > +int hv_common_cpu_init(unsigned int cpu)
> > +{
> > + void **inputarg, **outputarg;
> > + u64 msr_vp_index;
> > + gfp_t flags;
> > + int pgcount = hv_root_partition ? 2 : 1;
> > +
> > + /* hv_cpu_init() can be called with IRQs disabled from hv_resume() */
> > + flags = irqs_disabled() ? GFP_ATOMIC : GFP_KERNEL;
> > +
> > + inputarg = (void **)this_cpu_ptr(hyperv_pcpu_input_arg);
> > + *inputarg = kmalloc(pgcount * HV_HYP_PAGE_SIZE, flags);
>
> This is changed from alloc_pages to kmalloc. Does it ensure the
> alignment is still correct?
>
> Wei.
It does. The alignment guarantee made by kmalloc() was changed a
couple of years ago. See commit 59bb47985c1d. Here's the current text
from the comments preceding kmalloc():
* The allocated object address is aligned to at least ARCH_KMALLOC_MINALIGN
* bytes. For @size of power of two bytes, the alignment is also guaranteed
* to be at least to the size.
Michael
