| Message ID | 20200622162141.279716-7-imbrenda@linux.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Minor fixes, improvements, and cleanup | expand |
diff --git a/lib/vmalloc.c b/lib/vmalloc.c index 74b785c..83e34aa 100644 --- a/lib/vmalloc.c +++ b/lib/vmalloc.c @@ -20,10 +20,16 @@ static void *page_root; void *alloc_vpages(ulong nr) { + uintptr_t ptr; + spin_lock(&lock); - vfree_top -= PAGE_SIZE * nr; + ptr = (uintptr_t)vfree_top; + ptr -= PAGE_SIZE * nr; + vfree_top = (void *)ptr; spin_unlock(&lock); - return vfree_top; + + /* Cannot return vfree_top here, we are outside the lock! */ + return (void *)ptr; } void *alloc_vpage(void)
The pointer vfree_top should only be accessed with the lock held, so make sure we return a local copy of the pointer taken safely inside the lock. Also avoid doing pointer arithmetic on void pointers. Gcc allows it but it is an ugly hack. Use uintptr_t for doing maths on the pointer. This will also come useful in upcoming patches. Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> --- lib/vmalloc.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-)