[v6,bpf-next,3/5] vmalloc: WARN for set_vm_flush_reset_perms() on huge pages

Commit Message

Song Liu July 7, 2022, 10:35 p.m. UTC

VM_FLUSH_RESET_PERMS is not yet ready for huge pages, add a WARN to
catch misuse soon.

Suggested-by: Rick Edgecombe <[e-mail]>
Signed-off-by: Song Liu <[e-mail]>
---
 include/linux/vmalloc.h | 1 +
 1 file changed, 1 insertion(+)

Patch

diff --git a/include/linux/vmalloc.h b/include/linux/vmalloc.h
index 096d48aa3437..59d3e1f3e108 100644
--- a/include/linux/vmalloc.h
+++ b/include/linux/vmalloc.h
@@ -239,6 +239,7 @@  static inline void set_vm_flush_reset_perms(void *addr)
 {
 	struct vm_struct *vm = find_vm_area(addr);
 
+	WARN_ON_ONCE(is_vm_area_hugepages(addr));
 	if (vm)
 		vm->flags |= VM_FLUSH_RESET_PERMS;
 }