在 2023/4/11 11:42, Matthew Wilcox 写道:
On Mon, Apr 10, 2023 at 08:29:35PM -0700, Andrew Morton wrote:
On Tue, 11 Apr 2023 10:35:13 +0800 Peng Zhang zhangpeng.00@bytedance.com wrote:
The type of variable pointed to by pivs is unsigned long, but the type used in sizeof is a pointer type. Change it to unsigned long.
Thanks, but there's nothing in this changelog which explains why a -stable backport is being proposed. When fixing a bug, please always describe the user-visible effects of that bug.
There is no user-visible effect of this bug as the assembly code generated will be identical.
Therefore, if this has always been the case, cc stable is also unnecessary.
--- a/lib/maple_tree.c +++ b/lib/maple_tree.c @@ -3255,7 +3255,7 @@ static inline void mas_destroy_rebalance(struct ma_state *mas, unsigned char end if (tmp < max_p) memset(pivs + tmp, 0,
sizeof(unsigned long *) * (max_p - tmp));
sizeof(unsigned long) * (max_p - tmp));if (tmp < mt_slots[mt]) memset(slots + tmp, 0, sizeof(void *) * (max_s - tmp));
Is there any situation in which sizeof(unsigned long *) != sizeof(unsigned long)?
Windows 64-bit (pointer 64-bit, unsigned long is 32 bit) is the only one I know. Linux is all ILP32 or LP64. There may be some embedded environments which are different, but I have no idea what they might be.