5 Feb
2018
5 Feb
'18
8:48 a.m.
On 02/02/2018 08:20 PM, Matthew Wilcox wrote:
On Thu, Feb 01, 2018 at 11:22:55PM +0300, Andrey Ryabinin wrote:
vm = find_vm_area((void *)shadow_start);if (vm)vfree((void *)shadow_start);- }
This looks like a complicated way to spell 'is_vmalloc_addr' ...
It's not. shadow_start is never vmalloc address.
I'm confused. How can you call vfree() on something that isn't a vmalloc address?
​vfree() is able to free any address returned by __vmalloc_node_range(). And __vmalloc_node_range() gives you any address you ask. It doesn't have to be an address in [VMALLOC_START, VMALLOC_END] range.
That's also how the module_alloc()/module_memfree() works on architectures that have designated area for modules.