On Wed, Mar 28, 2018 at 05:49:23PM +0800, Jia He wrote:Frankly speaking, to me the root cause of that bug_on is not completedly
I took some time to look into the discussion, while the root cause seems not
On 3/28/2018 5:18 PM, Wei Yang Wrote:
Oops, I should reply this thread. Forget about the reply on another thread.Hi Wei
On Sun, Mar 25, 2018 at 08:02:15PM -0700, Jia He wrote:
Commit b92df1de5d28 ("mm: page_alloc: skip over regions of invalid pfnsWhy this has a bug? Do you have some link about it?
where possible") optimized the loop in memmap_init_zone(). But it causes
possible panic bug. So Daniel Vacek reverted it later.
If the audience could know the potential risk, it would be helpful to review
the code and decide whether to take it back.
Paul firstly submit a commit b92df1de5 to improve the loop in
memmap_init_zone.
And Daniel tried to fix a bug_on panic issue on X86 in commit 864b75f9d6b
because
there is evidence that this bug_on was caused by b92df1de5 [1].
But things didn't get better, 864b75f9d6b caused booting hang issue on
arm{64} [2]
So maintainer decided to reverted both b92df1de5 and 864b75f9d6b
[1] https://patchwork.kernel.org/patch/10251145/
[2] https://lkml.org/lkml/2018/3/14/469
clear now?