HI Andrew
在 2024/4/25 17:52, 杨欢 写道:
The problem is caused by set_page_owner alloc memory to save stack with
GFP_KERNEL in local_riq disabled.
So, we just can't assume that alloc flags should be same with new page,
let's split it. But in most situation, same is ok, in alloc_pages_bulk,
input GFP_ATOMIC when prep_new_pages
Please more fully describe the bug which is being fixed. A link to the
sysbot report would be helpful. I assume there was a stack backtrace
available? Seeing the will help others to understand the bug.
Sorry, here is the backtrace:
__dump_stack lib/dump_stack.c:79 [inline]
dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:96
___might_sleep.cold+0x1f1/0x237 kernel/sched/core.c:9153
prepare_alloc_pages+0x3da/0x580 mm/page_alloc.c:5179
__alloc_pages+0x12f/0x500 mm/page_alloc.c:5375
alloc_pages+0x18c/0x2a0 mm/mempolicy.c:2272
stack_depot_save+0x39d/0x4e0 lib/stackdepot.c:303
save_stack+0x15e/0x1e0 mm/page_owner.c:120
__set_page_owner+0x50/0x290 mm/page_owner.c:181
prep_new_page mm/page_alloc.c:2445 [inline]
__alloc_pages_bulk+0x8b9/0x1870 mm/page_alloc.c:5313
Thanks for your reply, but this patch was submitted in 2021, at that
time it was believed that bypassing
alloc bulk would suffice when page_owner is enabled, so this patch was
not considered.
Have you recently encountered any issues related to this?
Thanks.
And if you are able to identify the patch which introduced the bug, a
Fixes: tag would be helpful as well.
Thanks.
